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2. Comment on the paper “Lago Mare and the Messinian salinity crisis: Evidence from the Alboran Sea (S. Spain)” by Do Couto et al. (2014).
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Serrano, Francisco and Guerra-Merchán, Antonio
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SALINITY , *GEOLOGICAL basins , *PLIOCENE Epoch , *SEDIMENTARY basins - Abstract
The stratigraphic and temporal framework of the sedimentary filling of the Messinian–Zanclean transition in Malaga basin is discussed. From this framework, the main features of an alternative model for the Lago-Mare event in the Mediterranean are outlined. [ABSTRACT FROM AUTHOR]
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- 2015
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3. Introduction to the special collection of papers on the San Luis Basin Sustainability Metrics Project: A methodology for evaluating regional sustainability
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Heberling, Matthew T. and Hopton, Matthew E.
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GEOLOGICAL basins , *SUSTAINABILITY , *WATERSHEDS , *ECOLOGICAL impact , *WELFARE economics , *DECISION making in environmental policy , *RESEARCH methodology evaluation - Abstract
This paper introduces a collection of four articles describing the San Luis Basin Sustainability Metrics Project. The Project developed a methodology for evaluating regional sustainability. This introduction provides the necessary background information for the project, description of the region, overview of the methods, and summary of the results. Although there are a multitude of scientifically based sustainability metrics, many are data intensive, difficult to calculate, and fail to capture all aspects of a system. We wanted to see if we could develop an approach that decision-makers could use to understand if their system was moving toward or away from sustainability. The goal was to produce a scientifically defensible, but straightforward and inexpensive methodology to measure and monitor environmental quality within a regional system. We initiated an interdisciplinary pilot project in the San Luis Basin, south-central Colorado, to test the methodology. The objectives were: 1) determine the applicability of using existing datasets to estimate metrics of sustainability at a regional scale; 2) calculate metrics through time from 1980 to 2005; and 3) compare and contrast the results to determine if the system was moving toward or away from sustainability. The sustainability metrics, chosen to represent major components of the system, were: 1) Ecological Footprint to capture the impact and human burden on the system; 2) Green Net Regional Product to represent economic welfare; 3) Emergy to capture the quality-normalized flow of energy through the system; and 4) Fisher information to capture the overall dynamic order and to look for possible regime changes. The methodology, data, and results of each metric are presented in the remaining four papers of the special collection. Based on the results of each metric and our criteria for understanding the sustainability trends, we find that the San Luis Basin is moving away from sustainability. Although we understand there are strengths and limitations of the methodology, we argue that each metric identifies changes to major components of the system. [Copyright &y& Elsevier]
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- 2012
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4. Geohazard features of the Eastern Sardinia.
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Gamberi, Fabiano, Marani, Michael, Valle, Giacomo Dalla, Rovere, Marzia, Leidi, Elisa, Mercorella, Alessandra, and Ferrante, Valentina
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OCEANOGRAPHIC maps , *GEOLOGICAL basins , *SUBMARINE valleys , *BEACH erosion , *COASTAL zone management - Abstract
The MaGIC project (Marine Geohazard along the Italian Coasts) had the aim of mapping the geohazard in the Italian seas and resulted in numerous maps. In this paper, we present the maps: 'Maps of Geohazard features of the eastern Sardinian Margin'. The Eastern Sardinia margin has mainly a narrow shelf, which reaches a width of 20 km only to the north. At the base-of-slope, a series of intra-slope basins sits in the structural depressions formed during the opening of the Tyrrhenian back-arc system. Submerged, coastal depositional bodies are present in the Olbia area where the continental shelf is large. They most likely represent the remnants of coastal environments formed during the last rise in sea level. They can represent important geo-resources for application in the issue of coastal erosion management. They are also the site of ecosystems hosting a specific biodiversity, which need to be preserved. In the central and southern part of the mapped area, the shelf is very narrow with an average width of about 4 km. Here, many canyon heads are very close to the coastline. They develop through retrogadational processes. Particularly in those canyons, where the canyon heads reach the coast, sediment instability represents an important source of geohazards to the coastal regions. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Al and pH anomalies in the Manus Basin reappraised: Comments on the paper by T. Gamo et al.,...
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Resing, Joseph A. and Sansone, Francis J.
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PLUMES (Fluid dynamics) , *HYDROGRAPHIC surveying , *GEOLOGICAL basins - Abstract
Comments on a hydrographic survey of hydrothermal plumes of the Manus Basin in the Pacific Ocean. Anomalies in hydrogen-ion concentrations; Causes of hydrogen-ion concentration anomalies; Level of temperature of the area studied.
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- 1996
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6. Comment on the paper “Palynological records of the Permian Ecca Group (South Africa): Utilizing climatic icehouse-greenhouse signals for cross basin correlations” by K. Ruckwied, A. Götz and P. Jones (PPP, 413, 167-172, 2014).
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Cole, Doug
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PALYNOLOGY , *CLIMATE in greenhouses , *ICEHOUSES , *GEOLOGICAL basins ,ECCA Group - Published
- 2017
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7. Reply to the Comment by Côme Lefebvre on the paper: ‘Late Cretaceous extension and Palaeogene rotation-related contraction in Central Anatolia recorded in the Ayhan-Büyükkışla basin’ by Advokaat et al. 2014.
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Advokaat, Eldert L., van Hinsbergen, Douwe J.J., Kaymakcı, Nuretdin, Vissers, Reinoud L.M., and Hendriks, Bart W.H.
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GEOLOGICAL basins , *PALEOGENE - Abstract
A reply from the author of the article "Late Cretaceous extension and Palaeogene rotation-related contraction in Central Anatolia recorded in the Ayhan-Büyükkışla basin" in a 2014 issue is presented.
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- 2015
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8. Issue Information.
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GEOLOGICAL basins , *GEOLOGICAL time scales , *CARBONATE reservoirs , *WATERSHEDS , *ANTICLINES - Abstract
Shoaib I et al i . utilize advanced processing of recently-acquired wide-azimuth 3D seismic data, together with seismic attribute analysis and fracture modelling, to image fracture networks in the Paleogene carbonates at Ratana. These source rocks charge Paleogene and Miocene fluvio-deltaic sandstone reservoirs at about 40 oilfields including Urdaneta West, the focus of the paper on pp. 283-302 by B Escobar I et al., i b which has estimated reserves of about 1500 MM brl oil. The paper on pp. 253-282 by B Shoaib I et al i . b is a predictive study of the distribution of fractures in the low porosity Paleogene carbonates which serve as reservoir rocks at the Ratana field in the Upper Indus Basin, northern Pakistan. [Extracted from the article]
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- 2022
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9. Discussion of Papers.
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Aley, Tom
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DENSE nonaqueous phase liquids , *AQUIFERS , *GEOLOGICAL basins - Abstract
Comments on the paper `A Conceptual Model for DNAPL Transport in Karst Ground Water Basins.' Description of an epikarstic zone; Conceptual problems of the proposed epikarstic zone for storing dense nonaqueous phase liquids; View on working in a karst aquifer where contaminants are present.
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- 2001
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10. Successive formation of secondary pores via feldspar dissolution in deeply buried feldspar-rich clastic reservoirs in typical petroliferous basins and its petroleum geological significance.
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Cao, Yingchang, Yuan, Guanghui, Wang, Yanzhong, Zan, Nianmin, Jin, Zihao, Liu, Keyu, Xi, Kelai, Wei, Yihan, and Sun, Peipei
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GEOLOGICAL basins , *FELDSPAR , *SURFACE of the earth , *CLASTIC rocks , *HYDROCARBON reservoirs - Abstract
Clastic rock reservoirs in petroliferous basins are generally rich in feldspars. Feldspar dissolution has developed widely in clastic reservoirs, and the resulting secondary pores are crucial in deeply buried reservoirs. Based on a study of the diagenesis of clastic reservoirs in the Bohai Bay Basin, Tarim Basin, and Pearl River Mouth Basin and physical and numerical simulation experiments of fluid-rock interactions, this paper proposed a successive formation model of secondary pores via feldspar dissolution in deeply buried clastic reservoirs, considering the global research progresses in feldspar dissolution in clastic rocks. Feldspar dissolution can occur from shallow open systems to deep-ultra deep closed systems in petroliferous basins, resulting in the successive formation of secondary pores at different diagenetic stages. The successive mechanism includes three aspects. The first aspect is the succession of corrosive fluids that dissolve minerals. Meteoric freshwater dominates at the Earth's surface and the early diagenetic A stage. Subsequently, organic acids and CO2 formed via kerogen maturation dominate at the early diagenetic B stage to the middle diagenetic stage. CO2 and organic acids formed via hydrocarbon oxidation in hydrocarbon reservoirs dominate at the middle diagenetic B stage to the late diagenetic stage. The second aspect is the successive formation processes of secondary pores via feldspar dissolution. Large-scale feldspar secondary pores identified in deep reservoirs include secondary pores formed at shallow-medium depths that are subsequently preserved into deep layers, as well as secondary pores formed at deep depths. Existing secondary pores in deeply buried reservoirs are the superposition of successively feldspar dissolution caused by different acids at different stages. The third aspect is a successive change in the feldspar alteration pathways and porosity enhancement/preservation effect. Open to semi-open diagenetic systems are developed from the Earth's surface to the early diagenetic stage, and feldspar dissolution forms enhanced secondary pores. Nearly closed to closed diagenetic systems develop in the middle to late diagenetic stages, and feldspar dissolution forms redistributional secondary pores. The associated cementation causes compression resistance of the rock, which is favorable for the preservation of secondary pores in deep layers. These new insights extend the formation window of secondary pores in petroliferous basins from the traditional acid-oil generation window to a high-temperature gas generation window after hydrocarbon charging. The proposed model explains the genesis of deep-ultra deep high-quality reservoirs with low-permeability, medium-porosity and dominating feldspar secondary pores, which is significant for hydrocarbon exploration in deep to ultra-deep layers. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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11. GEOCHEMISTRY AND CARBON ISOTOPE CHARACTERISTICS OF ASSOCIATED GASES FROM OILFIELDS IN THE NW GREATER CAUCASUS, RUSSIA.
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Oblasov, N. V., Goncharov, I. V., Derduga, A. V., and Kunitsyna, I. V.
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CARBON isotopes , *GAS reservoirs , *OIL fields , *ISOTOPE geology , *ORGANIC geochemistry , *GEOLOGICAL basins - Abstract
The NW Greater Caucasus and surrounding areas have a long history of petroleum production dating back to the mid‐19th century. However the origin of the oil and gas is still a matter of debate. This paper focusses on a study area to the north of the western Greater Caucasus covering the West and East Kuban Basins and neighbouring structural highs where oil and natural gas occur in reservoir units of Neogene, Paleogene, Cretaceous and Jurassic ages. The study is based on the results of organic geochemical and stable carbon isotope analyses of 21 samples of associated gases from 16 oil fields. The gas samples' compositions were investigated together with the δ13C values of C1 to C5 alkanes. Twenty of the gas samples were of thermogenic origin and one was mixed (thermogenic and secondary microbial). δ13C values for CH4 for all the gas samples varied over a wide range from ‐62.3 to ‐30.0 ‰, indicating major variations in the thermal maturity of the respective source rocks. In a previous study, three genetic types of oil were identified in the study area and are referred to here as Types 1, 2 and 3. Gaseous hydrocarbons associated with Type 1 oils were generated by source rocks in the Middle Eocene Kuma Formation and the Oligocene (lower) part of the Maikop Group which are inferred to have been deposited in anoxic, deep‐marine conditions. C2–C5 alkanes in gases associated with Type 1 oils have the lowest (most negative) δ13C values of the samples studied, and the lowest iso‐butane: n‐butane and iso‐pentane: n‐pentane ratios. These gas samples were recovered from wells in oilfields located in the south and SE of the West Kuban Basin, in the Akhtyrskaya fault zone which extends along the northern flank of the Greater Caucasus foldbelt. Higher δ13C values of C2–C5 alkanes were found in gas samples associated with Type 2 oils which were recovered from wells in the central West Kuban Basin. The associated source rocks are interpreted to have been deposited in weakly oxidizing subaqueous conditions and to contain mainly marine organic matter but with an input of higher land plant material. The precise age and stratigraphic identity of the source rocks is unresolved but they may comprise the Upper Oligocene – Lower Miocene (middle and upper) part of the Maikop Group. In gases associated with Type 3 oils, δ13C values of ethane to pentane are similar to those of gases associated with Type 2 oils. These gases were recovered from wells in oilfields located on the Adygeya Swell which divides the southern East and West Kuban Basins and from the Armavir‐Nevinnomyssk Swell to the north. The precise source of these gases and oils is not known but the oils are probably older than Late Cretaceous on account of the absence of oleanane. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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12. ABSTRACTS OF PAPERS PRESENTED AT THE 50TH ANNIVERSARY MEETING OF THE ASSOCIATION OF AMERICAN GEOGRAPHERS, HELD AT PHILADELPHIA, PENNSYLVANIA, APRIL 11,12,13,14,15,1954.
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GEOGRAPHY , *GEOLOGICAL basins , *PLANTATIONS , *HISTORY of cartography - Abstract
Presents abstracts of articles presented at the 50th anniversary meeting of the Association of American Geographers in Philadelphia, Pennsylvania. "The Paris Basin in the Ninth Century: A Study of the Geography of Abbot Irminon's Polyptyque," by N. J. G. Pounds; "The Renaissance of the Southern Plantation," by Merle Prunty, Jr.; "The Changing Concept of Maps Through History," by Erwin Raisz.
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- 1954
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13. Research on geological and surfacial processes and major disaster effects in the Yellow River Basin.
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Lan, Hengxing, Peng, Jianbing, Zhu, Yanbo, Li, Langping, Pan, Baotian, Huang, Qiangbing, Li, Junhua, and Zhang, Qiang
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WATERSHEDS , *EARTH system science , *GEOLOGICAL research , *GEOLOGICAL basins , *GEOLOGY , *DISASTERS - Abstract
The Yellow River Basin (YRB) is characterized by active geological and tectonic processes, rapid geomorphological evolution, and distinct climatic diversity. Correspondingly, major disasters in the YRB are characterized by varied types, extensive distributions, and sudden occurrences. In addition, major disasters in the YRB usually evolve into disaster chains that cause severe consequences. Therefore, major disasters in the YRB destroy ecologies and environments and influence geological and ecological safety in the basin. This paper systematically reviews research on geological and surface processes, major disaster effects, and risk mitigation in the YRB, discusses the trends and challenges of relevant research, analyzes the key scientific problems that need to be solved, and suggests prospects for future research based on the earth system science concept. Themes of research that should be focused on include geological, surface and climatic processes in the YRB and their interlinking disaster gestation mechanisms; formation mechanisms and disaster chain evolutions of giant landslides in the upper reach of the YRB; mechanisms and disaster chain effects of loess water-soil disasters in the middle reach of the YRB; occurrence patterns and amplifying effects of giant flood chains in the lower reach of the YRB; and risk mitigations of major disasters in the YRB. Key scientific problems that need to be solved are as follows: how to reveal the geological, surface and climatic processes that are coupled and interlinked with gestation mechanisms of major disasters; how to clarify the mutual feedback effects between major disasters and ecology; and how to develop a human-environmental harmony-based integrated risk mitigation system for major disasters. Prospects for future studies that follow the earth system science concept include the following: highlighting interdisciplinary research to reveal the interlinked disaster gestation mechanisms of the geology, surface and climate in the YRB in the past, present, and future; forming theories to clarify the regional patterns, dynamic mechanisms, and mutual-feedback effects between disaster chains and ecology in the YRB on land and in rivers in the region; solving technological bottlenecks to develop assessment models and mitigation theories for integrated risks in the YRB by following the human-environment harmony concept; and finally, establishing a demonstratable application pattern characterized by "whole-basin coverage" and "zonal controls", thereby guaranteeing ecological and geological safety in the basin and providing scientific support for ecological conservation and high-quality development of the YRB. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Local separation of potential field anomalies using equivalent sources: application for the 3-D structure of mantle uplift beneath Von Kármán crater, the Moon.
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Zhang, Yi, Xu, Yixian, Mooney, Walter D, and Chen, Chao
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SPHERICAL coordinates , *LUNAR exploration , *MOON , *GEOLOGICAL basins , *LUNAR craters , *SPACE flight to the moon - Abstract
The separation of regional-residual anomalies plays an important role in the processing of potential field anomalies for obtaining better understandings of the nature of the underground sources. Many methods have been developed to achieve the separation of anomalies that are of distinct wavelengths. On the other hand, fewer studies have addressed the separation of local anomalies from the observed potential field anomalies. In this paper, we introduce a new process for separating localized anomalies from the observations under the Cartesian and spherical coordinates. The separation is achieved using the equivalent source technique and an iterative inversion process which is to refine and finalize the separated local anomalies. Additionally, we introduce an inversion method for determining the equivalent sources that are of varying dimensions, as well as a quantitative measurement to assess the accuracy of the separation process. Verified with synthetic examples, the proposed method could extract arbitrary shaped local anomalies from the rest with low error levels. Subsequently, we apply the method to the construction of a 3-D model of the mantle uplift beneath the Von Kármán crater (VKC) on the Moon. The VKC is the landing site of the Chinese lunar exploration mission Chang'e 4, which lies in the northwestern portion of the South-Pole Aitken (SPA) basin on the far side of the Moon. Multiple generations of mare basalts are identified within the VKC, which indicates a complex geological history of the basin. Insights into the evolutionary history of this region can be obtained by investigating the deep crustal structure of the VKC using topographic and gravity data. Processed with the proposed method, the 3-D structure we obtain provides evidence for separated mantle uplifting events triggered by the two impact events that created the VKC and the Von Kármán M crater, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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15. The action of long multi-year ridges on upward sloping conical structures.
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Croasdale, Ken, Brown, Tom, Li, George, Spring, Walt, Fuglem, Mark, and Thijssen, Jan
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MID-ocean ridges , *GROUND penetrating radar , *ALGORITHMS , *GEOLOGICAL basins , *PROBABILISTIC databases - Abstract
In ISO 19906 (2010) , there are no algorithms provided for calculating loads on sloping structures due to interaction with multi-year (MY) ridges; only references are provided for a range of methods. A study was undertaken to review and improve the theories for MY ridge breaking and ride-up on a slope. This article reports on the new methods developed for long ridges which are defined as being long enough to develop both centre and hinge cracks. Short ridges, which are defined as being too short to develop hinge cracks, have also been investigated and new theories for short ridges are reported in an accompanying paper. The new method for long ridges includes a simplified approach for secondary failures of the hinge pieces which are successively broken as a ridge is pushed higher prior to rotation of the broken pieces around the structure. As well, for wide ridges, a new theory for failure across their width has been developed which leads to lower loads than if this failure mode is not included. Results using the new methods have been compared to tests conducted at the Imperial Oil outdoor ice basin in Calgary. These are the largest scale tests ever conducted in studying multi-year ridge loads on conical structures. A recommended methodology which includes closed-form equations for the various load components is presented. The method is considered suitable for inclusion in probabilistic methods and in future code developments. In this paper, examples of deterministic loads on typical Arctic structures are given. Continuing uncertainties are discussed and recommendations are made to address them. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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16. Forthcoming papers.
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RESEARCH , *SEDIMENTOLOGY , *SEDIMENTATION & deposition , *GEOLOGICAL basins , *MORPHOLOGY , *SAND waves - Abstract
Presents research papers related to sedimentology. "Wind Sedimentation in the Jafurah Sand Sea, Saudi Arabia," by Steven G. Fryberger; "Deltaic Sedimentation in the Lake Hazar Pull-apart Basin, South-eastern Turkey," by L. A. Dunne and M. R. Hempton; "Morphology and Internal Structure of Sandwaves in the Bay of Fundy," by Robert W. Dalrymple.
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- 1984
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17. Serious gaming for participatory planning of multi-hazard mitigation.
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Carson, Andrea, Windsor, Mary, Hill, Harvey, Haigh, Tonya, Wall, Nicole, Smith, Jason, Olsen, Rolf, Bathke, Deborah, Demir, Ibrahim, and Muste, Marian
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GEOLOGICAL basins , *WATER management , *GAME theory , *DECISION support systems , *STAKEHOLDERS - Abstract
Collaborative, holistic, and proactive planning for basin-wide water management solutions addressing multiple water-related hazards is challenging. Shared vision planning (SVP) and decision support systems (DSSs) are two approaches that have been used to address the challenges described. SVP is a participatory planning process. DSSs can efficiently support the integration of multiple and vast amounts of information and interactively illustrate the trade-offs between alternative mitigation plans. While SVP and DSS have been previously used to help stakeholders to better understand watershed processes and how to arrive at collaborative basin-wide decisions, coupling these tools with serious gaming is an emerging effort. The multi-hazard tournament (MHT) framework is an example of the integration of serious gaming, DSS and SVP. The MHT is based on the premise that almost all cultures and individuals understand and enjoy sports, teams and structured games. This paper first introduces a new approach called the MHT which couples serious gaming via the use of DSS with the traditional SVP concepts of (1) collaborative computer modelling, (2) traditional water resources planning, and (3) structured public participation through a case study of the Cedar Rapids, Iowa MHT. Second, it examines and discusses the effectiveness of this combined approach in achieving objectives often established in collaborative, watershed scale: decision-making, social learning, and relationship building. An analysis of the Cedar Rapids MHT survey results show that the integration of the Iowa watershed decision support system, SVP, and serious gaming framework served as a valuable tool for examining trade-offs between mitigation options and their impacts. The Cedar Rapids MHT survey results indicated this was also an adequate means of capacity building, social learning, and meaningfully engaging the community in mitigating hazards posed in their watersheds. The paper also explores how the integration of SVP, DSS, and serious gaming with some refinements could be used to practically support watershed scale planning and decision-making processes. [ABSTRACT FROM AUTHOR]
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- 2018
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18. Lessons learned from the 2016 Yangtze River flood in Anhui province, China.
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Cheng, Xiaotao, Wan, Hongtao, Huang, Shifeng, Li, Changzhi, and Zhang, Hongbin
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RAINSTORMS , *PSYCHOLOGICAL adaptation , *FLOODS , *GEOLOGICAL basins - Abstract
During the flood season of 2016, the middle and lower reaches of the Yangtze River suffered the worst flooding since 1999, involving Hunan, Hubei, Anhui, Jiangxi and Jiangsu provinces and the Taihu Basin. Based on the field survey at eight counties on both sides along the Yangtze River in Anhui Province, this paper analyses the features of rainstorm, flood and the resulting disaster in 2016 over there, and identifies problems and difficulties existing in flood prevention and disaster reduction under the new situation of social and economic development. Furthermore, this paper discusses the coping strategies and measures on advancing the comprehensive flood management mode of human-water harmony, managing middle and small rivers and strengthening the key basic research on flood control and disaster reduction under the new situation. [ABSTRACT FROM AUTHOR]
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- 2018
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19. Interpreting the results of in situ pull tests on Friction Rock Stabilizers (FRS).
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Nicholson, Luke and Hadjigeorgiou, John
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HARD rock mining , *QUALITY control , *QUALITY assurance , *GEOLOGICAL basins - Abstract
Friction Rock Stabilizers (FRS) are widely used in underground hard rock mines. An important element of Quality Control and Assurance practice is the use of in situ pull tests. Individual mines undertake in situ pull tests to demonstrate that suitable installation conditions exist for different reinforcement elements, and whether the selected bolts comply with the required standards. This paper reports on a review of 533 pull tests on FRS bolts in six underground hard rock mines in the Sudbury basin. It provides a critical review of factors that influence the performance of FRS bolts. The results are analyzed to provide design values for FRS that can be used as input to deterministic and probabilistic design. The paper concludes with a discussion on the practical implications of the results. [ABSTRACT FROM AUTHOR]
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- 2018
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20. Frequency based imputation of precipitation.
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Dikbas, Fatih
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PHYSIOLOGICAL effects of climate change , *METEOROLOGICAL precipitation , *GEOLOGICAL basins , *REGRESSION analysis , *GENETIC algorithms - Abstract
Changing climate and precipitation patterns make the estimation of precipitation, which exhibits two-dimensional and sometimes chaotic behavior, more challenging. In recent decades, numerous data-driven methods have been developed and applied to estimate precipitation; however, these methods suffer from the use of one-dimensional approaches, lack generality, require the use of neighboring stations and have low sensitivity. This paper aims to implement the first generally applicable, highly sensitive two-dimensional data-driven model of precipitation. This model, named frequency based imputation (FBI), relies on non-continuous monthly precipitation time series data. It requires no determination of input parameters and no data preprocessing, and it provides multiple estimations (from the most to the least probable) of each missing data unit utilizing the series itself. A total of 34,330 monthly total precipitation observations from 70 stations in 21 basins within Turkey were used to assess the success of the method by removing and estimating observation series in annual increments. Comparisons with the expectation maximization and multiple linear regression models illustrate that the FBI method is superior in its estimation of monthly precipitation. This paper also provides a link to the software code for the FBI method. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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21. Mesozoic multistage structural deformation along the Ke‐Bai fault zone in the north‐west Junggar Basin, NW China.
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Yan, Dezhi, Xu, Huaimin, Xu, Zhaohui, Tian, Miao, Lei, Zhicheng, and Liu, Y.
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FAULT zones , *GEOLOGICAL basins , *PETROLEUM prospecting , *RIFTS (Geology) , *STRIKE-slip faults (Geology) , *THRUST , *GEOLOGIC faults - Abstract
The Junggar Basin is one of the main oil basins in Northwest China, and the north‐west part of the basin is a significant petroleum exploration target. Mesozoic structural activity had an important influence on the present structural characteristics of the north‐west Junggar Basin. In this paper, we discuss the tectonic evolution of the Junggar Basin by studying the structural characteristics of the Ke‐Bai Fault. Our results suggest that the Ke‐Bai Fault has obvious strike‐slip characteristics and that it is an important basin‐controlling fault that has controlled the tectonic evolution of the north‐west Junggar Basin. The Junggar Basin was a rift basin in the Early Permian, but it experienced a tectonic reversal during the Middle Permian to the Triassic. The Ke‐Bai Fault changed from a normal fault into a thrust fault from the Early Permian to the Triassic. During the Jurassic, dextral strike‐slip structures developed along the Ke‐Bai Fault, horsetail splay faults developed in its north segment, and there is evidence that it was under WNW–ESE compression. The dextral strike‐slip faulting of the Ke‐Bai Fault is consistent with tectonic movement along the Kelameili, Sangequan, Wu‐Xia, Hong‐Che, and North Tianshan fault systems in the Junggar Basin. We therefore infer that counterclockwise rotation occurred in the Junggar Basin in the Jurassic. [ABSTRACT FROM AUTHOR]
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- 2020
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22. Why groundwater matters: an introduction for policy-makers and managers.
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Kath, Jarrod and Dyer, Fiona J.
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GROUNDWATER , *WATER management , *ENVIRONMENTAL policy , *DROUGHTS , *WATER supply , *GEOLOGICAL basins , *GOVERNMENT policy , *PREVENTION - Abstract
In many parts of the world the combined pressures of population growth and a drying climate have resulted in the proliferation of water focused policies which aim to increase the resilience of socio-ecological systems. Until recently, these policies often reflected surface water centric views of water resources, with groundwater receiving scant attention. In this paper we provide an introduction to the importance of groundwater for water-dependent socio-ecological systems and why it needs to be better incorporated into environmental water management policies. Specifically we highlight the key role of groundwater in buffering the environment and socio-economic activities against drought. We also outline some of the key challenges that face policy-makers and managers implementing groundwater management policies. These include dealing with groundwater resources that are spatially and temporally mismatched with surface water resources; transboundary governance issues; challenges between focusing on either preventative or restorative actions and most importantly limited knowledge about groundwater resources and groundwater–ecology relationships. We hope that the information in this paper will assist in the development of sustainable surface-groundwater water management policies, as well as highlight important challenges that should be considered before implementing groundwater related policies. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
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23. Analogue modelling and mechanism of tectonic inversion of the Xihu Sag, East China Sea Shelf Basin.
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Wang, Qian, Li, Sanzhong, Guo, Lingli, Suo, Yanhui, and Dai, Liming
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GEOLOGICAL basins , *PLATE tectonics , *GEOLOGIC faults , *STRUCTURAL geology , *GEOMETRY - Abstract
The East China Sea Shelf Basin lies between the Pacific Subduction and Indian-Eurasian Collision tectonic domains and records Cenozoic tectonic inversion, especially in the Xihu Sag. To improve the understanding of the evolution and mechanism of tectonic inversion, this paper employs analogue modelling to reproduce the evolutionary process. Combined with the structural analysis of seismic profile, this paper determines the pattern of basement-involved faults. Simulation results show that under the transtension, two subsidence centers developed and a number of normal faults assembled in two flower structures. When the stress field turned into transpression, the geometry and deformation of inversion basin inherited the previous transtensional basin and pre-existing faults, respectively. The geometry and fault patterns in models are well consistent with those observed in the Xihu Sag, which indicates the plausibility of similar deformation controls. The formation of the tectonic inversion is related to the variation in stress field caused by the changes in the rates and directions of the subduction of the Pacific Plate and the collision of the Indian Plate with Eurasian Plate. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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24. Flood risk zoning using a rule mining based on ant colony algorithm.
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Lai, Chengguang, Shao, Quanxi, Chen, Xiaohong, Wang, Zhaoli, Zhou, Xiaowen, Yang, Bing, and Zhang, Lilan
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FLOOD risk , *FLOODS , *ENVIRONMENTAL risk assessment , *ANT algorithms , *NATURAL disasters , *GEOLOGICAL basins , *MANAGEMENT - Abstract
Risk assessment is a preliminary step in flood management and mitigation, and risk zoning provides a quantitative measure of flood risk. The difficulty in flood risk zoning is to deal with the complicated non-linear relationship among indices and risk levels. To solve this problem, the ant colony algorithm based on rule mining (Ant-Miner) is promoted in this paper to map the regional flood risk at grid scale. For the case study in the Dongjiang River Basin in Southern China, 11 and 14 indices (without and with the socio-economic indices considered) are respectively chosen to construct the zoning model based on Ant-Miner. The results show that Ant-Miner exhibits higher accuracy and more simple rules that can be used to generate flood risk zoning map quickly and easily than decision tree method (DT); compared to random forest (RF) and fuzzy comprehensive evaluation (FCE), Ant-Miner has significant advantages both in implementation step-reducing and computing time-saving. Although the comprehensive measure and natural hazard measure of flood risk distributed similarly over the entire region, the former one which considered the socio-economic indices is more reasonable in term of real impact to natural and socio-economy. The areas with high-risk level obtained in this paper matched well with the integrated risk zoning map and the inundation areas of historical floods, suggesting that the proposed Ant-Miner method is capable of zoning the flood risk at grid scale. This study shows the potential to provide a novel and successful approach to flood risk zoning. Evaluation results provide a reference for flood risk management, prevention, and reduction of natural disasters in the study basin. [ABSTRACT FROM AUTHOR]
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- 2016
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25. The Australian Murray–Darling Basin Plan: challenges in its implementation (part 1).
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Hart, Barry T.
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GEOLOGICAL basins , *URBANIZATION , *WATER resources development , *WATER utilities , *TASK analysis - Abstract
The latest in a set of major water reforms in the Australian Murray–Darling Basin occurred in November 2012 with completion of a new integrated water resources plan for the region (the Basin Plan). This occurred over a four-year period (2009–12) and was not without controversy. However, perhaps the most challenging part of this reform is occurring now with the implementation of the Basin Plan between 2012 and 2024. This paper discusses the key tasks to be undertaken by June 2016 and the main challenges in their implementation. A companion paper discusses the challenges in implementing the other tasks that need to be settled by 2024. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
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26. The Australian Murray–Darling Basin Plan: challenges in its implementation (Part 2).
- Author
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Hart, Barry T.
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GEOLOGICAL basins , *WATER resources development , *WATER utilities , *PROJECT management , *BUILD operate transfer - Abstract
The most recent major water reform in the Australian Murray–Darling Basin occurred in November 2012 with the development of a new integrated water resources plan for the region (the Basin Plan). This occurred over a four-year period (2009–12). An equally challenging part of this reform is occurring now with the implementation of the Basin Plan between 2012 and 2024. This paper discusses the challenges in implementing the key tasks that must be completed in the longer term by 2024. A companion paper discusses the challenges in implementing the more immediate tasks that must be completed by June 2016. [ABSTRACT FROM PUBLISHER]
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- 2016
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27. Integrated geo-microbial and trace metal anomalies for detection of hydrocarbon microseepage in Ahmedabad block of Cambay basin, India.
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Rasheed, M., Srinivasa Rao, P., Boruah, Annapurna, Hasan, Syed, Mohamed Seddik, Bougi, Pandey, Disha, and Harinarayana, T.
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GEOLOGICAL basins , *TRACE metals , *HYDROCARBONS , *ANALYTICAL geochemistry , *OXIDATION-reduction reaction - Abstract
The aim of the present work is to define the geo-microbial signatures along with trace metals, and to investigate whether the geo-microbial anomalies have correlation with trace metal anomalies in Ahmedabad block of Cambay basin. The surface geochemical techniques are based on seepage of light hydrocarbon gases from the oil and gas pools to the shallow surface and can bring up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations and hydrocarbon oxidizing bacteria and its interrelationship. For the purpose a total of 90 soil samples are collected in grid pattern of 2 x 2 km interval. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. The concentrations of V (0 to149 ppm), Cr (2 to 192 ppm), Cu (4 to 171 ppm), Se (98 to 440 ppm), Zn (56 to 1215 ppm) are obtained. It is observed that the concentrations of trace elements are tremendously increased when they are compared with their normal concentrations in soils. In this study the hydrocarbon oxidizing bacterial counts ranged between 1.0 x 10 and 1.59 x 10 cfu/g of soil sample respectively. The attempt has made for the first time, which revealed good correlation as both these anomalies are found as apical in relation. Integrated studies between trace elements and hydrocarbon oxidizing bacterial anomalies showed positive correlation with existing oil and gas wells in the study area. [ABSTRACT FROM AUTHOR]
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- 2016
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28. A novel hybrid PV-distillation system.
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Al-Nimr, Moh’d A. and Al-Ammari, Wahib A.
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PASSIVE solar energy systems , *GEOLOGICAL basins , *DISTILLATION , *CAPACITORS , *SIMULATION methods & models , *SOLAR radiation - Abstract
A novel PV/T-distillation system has been introduced in this paper. The main parts of the proposed system are a single slope basin solar still with PV/T cell immersed at the bottom of its basin and coupled with outside finned condenser. A steady-state mathematical model has been developed to study the performance of the system. The simulation results show a good agreement with those obtained by some theoretical and experimental published studies for systems similar, in general, for our proposed system. Also, in this paper, the effects of solar radiation, wind speed, ambient temperature and condensing chamber on the performance of the system have been discussed. [ABSTRACT FROM AUTHOR]
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- 2016
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29. Architecture and development of the Magdalena Submarine Fan (southwestern Caribbean).
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Idárraga-García, Javier, Masson, Douglas G., García, Jacqueline, León, Hermann, and Vargas, Carlos A.
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SUBMARINE fans , *GEOLOGICAL basins , *TURBIDITY currents , *CONTINENTAL shelf , *MULTIBEAM mapping , *ARCHITECTURE - Abstract
Submarine fans are the largest sediment accumulations on Earth and are key to study the sediment-transfer zone between terrestrial source area and deep-sea depositional sink. They provide information of past climate, tectonics, carbon global inventory, and can be prolific hosts for oil/gas resources. In this paper, we present, for the first time, an analysis of the entire Magdalena Submarine Fan (MSF), from the shelf break to the distal domain, based on ~224,000 km2 of multibeam bathymetry, as well as backscatter, subbottom profiler and regional/local seismic reflection data recently acquired in southwestern Caribbean Sea. The aim is to describe in detail the MSF morphology and depositional architecture, propose a fan segmentation landform assemblage, and determine its extent within the deep basin. Three fan segments are identified: upper, middle and lower fans. The upper fan extends from the coastline to a depth of ~3000 m. Its eastern sector is characterized by a canyon system off the present-day mouth of the Magdalena River, through which most of the sediments are transported downslope to be deposited in intra-slope basins bounded by structural highs of the South Caribbean Deformed Belt. The western upper fan is characterized by distinct channel-levee complexes that are partially removed by mass transport complexes that originated near the continental shelf edge. The upper to middle fan transition is marked by a decrease in regional gradient from 1° to about 0.3° and local relief, a change from large, irregular sediment waves to more regular waves that slowly decrease in amplitude downslope, and the appearance of erosional megascours. The middle fan bedform assemblage evidences the presence of a channel-lobe transition zone in this sector of the MSF, separating well-defined, upper fan channels from lower fan depositional lobes. The middle to lower fan transition occurs between ~3800 and ~3950 m and is defined by a further decrease in gradient and by a change from sediment waves to planar parallel-bedded reflectors on subbottom profiles. The lower fan extends to a maximum depth of ~4250 m and is characterized by an almost flat seabed (slope of 0.05°), interrupted by a few isolated bathymetric highs and low-relief channels (<5 m deep). The entire area of the lower fan is interpreted as an area of turbidity current deposition, with relatively sandy sediments in the south and west giving way to muddier sediments in the northeast, which could correspond to distal fan lobes. The identification of four regional seismic facies related to MSF sedimentation allowed us to constrain the fan extent in the southwestern sector of the Caribbean. Distally, within the Colombia Basin the fan terminates against areas of elevated seafloor (Kogi-Coyaima and Quimbaya seamounts, Aruzi and Ticuna hills, and Beata Ridge), which have acted as barriers to sedimentation. Nevertheless, it was determined that the MSF extends beyond the Colombia Basin and locally reaches the Lower Nicaraguan Rise. In this new scenario, we established that the MSF is much more extensive than previously recognized, with an area of ~237,000 km2, which puts it among the World's largest submarine fans. • The morpho-structure of the entire Magdalena Submarine Fan (MSF) is presented • Upper, middle and lower fan segments are proposed from diverse landform assemblages • Channel-levee complexes partially removed by extensive MTCs defines the upper fan • Middle fan, with sediment waves and megascours, is defined as sediment bypass area • Evidence of turbidity current sedimentation, with probable lobes, in the lower fan [ABSTRACT FROM AUTHOR]
- Published
- 2019
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30. Geological and geomorphic evidence for activity of the Mengzi fault along the southeastern margin of the Tibetan Plateau.
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Zhang, Yang, He, Zhongtai, Ma, Baoqi, Wang, Jinyan, Zhang, Hao, and Wang, Jinpeng
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GEOMORPHOLOGY , *GEOLOGICAL basins , *EARTHQUAKES , *HAZARD mitigation - Abstract
Graphical abstract Highlights • The geometric distribution and activity of the Mengzi fault has been studied. • The horizontal slip rate of the fault has been obtained via the offset gullies and terraces. • Three paleo-events since 30–40 ka BP have been observed, with a 10-ka major earthquake recurrence period. • The Mengzi fault plays an important role in the adjustment of the large slip rate loss for the southern Xiaojiang fault. Abstract Few studies have been conducted on the activity of the Mengzi fault system, which is located to the southeast of the Sichuan-Yunnan block. The Mengzi fault is distributed along the eastern margin of the Mengzi basin. However, little is known about the location, length, and activity of the fault or the occurrence of paleo-earthquakes during the late Quaternary. This paper studies the geometric distribution and activity of the fault via remote sensing imagery interpretation, fault outcrops in the area, faulted landforms and chronological analyses. The results show that the Mengzi fault extends from Nandong (Kaiyuan basin) in the north through the eastern margin of the Mengzi basin to Pingbian in the southeast, eventually intersecting with the Honghe fault. The Mengzi fault is approximately 250 km long and is characterized as a reverse strike-slip fault. We survey and calculate the offset gullies and terraces dislocated by the fault; combined with sample dating, we calculate the horizontal slip rate of the fault since 30 ka BP to be 0.91–1.56 mm/a. Three paleo-events since 30–40 ka BP are observed with a 10-ka major earthquake recurrence period. We analyze the relationships among the Mengzi fault, southern Xiaojiang fault, and Qujiang-Jianshui fault and note a slip rate loss of ≥8 mm/a from the southern Xiaojiang fault that was absorbed by reverse dextral strike-slip faulting and lateral shortening of the Qujiang-Jianshui fault and the Mengzi fault. The Mengzi fault plays an important role in the adjustment of the large slip rate reduction along the southern Xiaojiang fault. Moreover, the Mengzi fault has a similar tectonic position to the seismogenic faults of the 2008 Wenchuan earthquake, 2013 Lushan earthquake and 2014 Ludian earthquake, and the Mengzi fault and southern Xiaojiang fault both accumulate the energy generated by the southeastward movement of the Sichuan-Yunnan block. Studies on the Mengzi fault are helpful for renewing our understanding of the tectonic patterns of the southeastern Sichuan-Yunnan block and delimiting the boundary of the southeastern block margin. Furthermore, because the cities of Mengzi and Kaiyuan are located along the Mengzi fault, this study has practical significance for earthquake disaster mitigation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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31. Regional paleoclimates and local consequences: Integrating GIS analysis of diachronic settlement patterns and process-based agroecosystem modeling of potential agricultural productivity in Provence (France).
- Author
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Contreras, Daniel A., Hiriart, Eneko, Bondeau, Alberte, Kirman, Alan, Guiot, Joël, Bernard, Loup, Suarez, Romain, and Van Der Leeuw, Sander
- Subjects
- *
AGRICULTURAL ecology , *AGRICULTURAL productivity , *GEOLOGICAL basins , *PALEOCLIMATOLOGY , *GEOGRAPHIC information systems - Abstract
Holocene climate variability in the Mediterranean Basin is often cited as a potential driver of societal change, but the mechanisms of this putative influence are generally little explored. In this paper we integrate two tools–agro-ecosystem modeling of potential agricultural yields and spatial analysis of archaeological settlement pattern data–in order to examine the human consequences of past climatic changes. Focusing on a case study in Provence (France), we adapt an agro-ecosystem model to the modeling of potential agricultural productivity during the Holocene. Calibrating this model for past crops and agricultural practices and using a downscaling approach to produce high spatiotemporal resolution paleoclimate data from a Mediterranean Holocene climate reconstruction, we estimate realistic potential agricultural yields under past climatic conditions. These serve as the basis for spatial analysis of archaeological settlement patterns, in which we examine the changing relationship over time between agricultural productivity and settlement location. Using potential agricultural productivity (PAgP) as a measure of the human consequences of climate changes, we focus on the relative magnitudes of 1) climate-driven shifts in PAgP and 2) the potential increases in productivity realizable through agricultural intensification. Together these offer a means of assessing the scale and mechanisms of the vulnerability and resilience of Holocene inhabitants of Provence to climate change. Our results suggest that settlement patterns were closely tied to PAgP throughout most of the Holocene, with the notable exception of the period from the Middle Bronze Age through the Early Iron Age. This pattern does not appear to be linked to any climatically-driven changes in PAgP, and conversely the most salient changes in PAgP during the Holocene cannot be clearly linked to any changes in settlement pattern. We argue that this constitutes evidence that vulnerability and resilience to climate change are strongly dependent on societal variables. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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32. Simulations on recoverability performances for a coalbed methane field in SE edge of Ordos basin, China.
- Author
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Zou, Mingjun, Wei, Simin, Huang, Zhiquan, Lv, Xiaochun, and Guo, Biao
- Subjects
- *
COALBED methane , *GEOLOGICAL modeling , *GEOLOGICAL basins , *COMPUTER simulation , *DRAINAGE - Abstract
This paper mainly studies the recoverability performances for a coalbed methane (CBM) field located in the southeastern edge of the Ordos basin of China. Geological models are established, and drainage performances for four typical wells are described in detail. Single well simulations for the four wells are conducted to check accuracies of parameters and predict well drainage performances, and optimizations of well spaces are simulated to determine the most suitable well space. Results indicate that the reservoir parameters used in this study are quite accurate, and the well space of 350 × 300 m is most suitable in this area. Furthermore, the fifteen years’ field simulation under the well space of 350 × 300 m is conducted, which shows that the well number, average production and cumulative production are 1944, 7.01 × 10 8 m 3 /d and 105.22 × 10 8 m 3 , respectively. To validate the well space used in this study, analyses of recoverability and economic profit are conducted, both of which demonstrate that the well space of 350 × 300 m is most suitable in this area and can bring a stable drainage performance for a long time and get a high gas production. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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33. Quantifying the edge-induced seismic aggravation in shallow basins relative to the 1D SH modelling.
- Author
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Zhu, Chuanbin, Chávez-García, Francisco J., Thambiratnam, David, and Gallage, Chaminda
- Subjects
- *
GEOLOGICAL basins , *SEDIMENTARY basins , *EARTHQUAKE resistant design , *SOIL profiles , *SEISMOGRAMS - Abstract
Abstract Basin effects have long been proven to be of significance to seismic ground motions. However, 1D site response analysis, especially based on the equivalent nonlinear method, dominates engineering practice. In this paper, we aim to quantify the edge-induced aggravation in shallow sedimentary basins in addition to the 1D site effects. We chose a fixed shape for all shallow basins. Vertical heterogeneities are configured based on 31 KiK-net site profiles, complemented by another 19 hypothetic soil profiles. We then simulate both the 1D and 2D ground motions of each basin subjected to nine earthquake records modelled as vertically propagating SH waves. We use the aggravation factor, the ratio of 2D to 1D response spectra, to characterize the additional amplification induced by the lateral heterogeneity. Our results indicate that, for shallow basins, it is the region close to the basin edge that experiences the most significant aggravation, increasing 1D amplification by a factor between 1.2 and 1.5 mainly within the period band from 0.1 s to T h , where T h is the 1D fundamental resonance period at the basin centre. Highlights • For shallow basins, ground motions in a close-to-edge region are significantly aggravated. • Ground motion aggravation in shallow basins is period-dependent. • Ground motions in shallow basins are aggravated by a factor mainly between 1.2 and 1.5. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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34. Magnetochronology of Late Miocene Mammal Fauna in Xining Basin, NE Tibetan Plateau, China.
- Author
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HAN, Jian'en, SHAO, Zhaogang, CHEN, Qiguang, ZHANG, Qianqian, YU, Jia, WANG, Jin, ZHU, Dagang, XU, Biao, MENG, Qingwei, and ZHANG, Xuefeng
- Subjects
- *
FOSSIL mammals , *GEOLOGICAL time scales , *MIOCENE stratigraphic geology , *TIBETAN chronology , *GEOLOGICAL basins - Abstract
The Xining basin is located in the northeastern margin of the Qinghai‐Tibet Plateau. It is a rift basin formed in Mesozoic and Cenozoic and structurally belongs to the intersection of Kunlun and Qilian Mountains. Cenozoic fluvial and lacustrine sedimentary strata are continuous in the Xining basin, with a thickness of more than 800 m, completely recording the deformation uplifting, weathering and denudation history and climate change process of the northeastern plateau. Currently, early Miocene Xijia fauna, early Middle Miocene Danshuilu fauna and late Middle Miocene Diaogou fauna are discovered in the Xining basin, which provide an important basis for the stratigraphic correlation of the Cenozoic strata in the Xining basin. However, in the next few decades, there are no reports about the large mammal fossils in the Xining basin, especially about late Miocene fauna. The author discovered a large amount of mammal fossils in the Neogene sedimentary strata in Huzhu area, Xining basin. According to the identification results of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, these fossils mainly included Hipparion dongxiangense, Chilotherium sp., Parelasmotherium sp., Stephanocemas sp. and Kubanochoerus sp. and their age was early Late Miocene. Since the discovery of this set of fossils directly filled the blank that there were no large mammal fossils in the Xining basin in Late Miocene, it was very important for studying the magnetic stratigraphic chronology of fossil‐forming strata and establishing the paleomagnetic chronology scale plate of mammal fossils. In this paper, the paleomagnetic data of the fossil‐forming stratigraphic profile, Banyan profile, were measured and the paleomagnetic records were collected through high density sampling, and finally the paleomagnetic polarity column of the profile was established. The results showed that five positive and five negative polarity segments were recorded in Banyan profile, which corresponded well to the polarity between C3Br.1n‐C4n.2n in the standard polarity column. The age of profile top was about 7.25 Ma and profile bottom was about 8.4 Ma, with an age range of 1.15 Ma. The mammal fossils discovered this time were exposed between positive and negative polarities N5 and R5 at the bottom of the profile, corresponding to C4r.1r at negative polarity and C4n.2n at positive polarity in the standard polarity column. The age of mammal fossils was about 8.3 Ma. The paleomagnetic chronology of the strata and paleontological fossils determined the absolute age of late Miocene mammal fossils and expanded the upper age of late Miocene Xianshuihe Formation (N1xn) in the Xining basin, which had provided new basic data for further studying the stratigraphic deposition and correlation of late Cenozoic strata and regional environmental evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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35. Drillhole uncertainty propagation for three-dimensional geological modeling using Monte Carlo.
- Author
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Pakyuz-Charrier, Evren, Giraud, Jérémie, Ogarko, Vitaliy, Lindsay, Mark, and Jessell, Mark
- Subjects
- *
GEOLOGICAL basins , *PROBABILITY theory , *MARKOV processes , *MONTE Carlo method ,MATHEMATICAL models of uncertainty - Abstract
Abstract Monte Carlo Uncertainty Estimation (MCUE) is an emerging heuristic uncertainty propagation method designed to provide reliable and time/cost efficient estimates of geometrical uncertainties in 3D geological modeling. MCUE is a subtype of Bayesian Monte Carlo method similar to geostatistical simulation. The methods described here rely on disturbance probability distributions that are parameterized to best represent individual input uncertainty. Essentially, disturbance distributions quantify the error about the location (x, y, z) and orientation (dip and azimuth) of observed geological structures. The disturbance distributions are sampled either independently or via a Markov-Chain to produce many plausible alternative datasets. These plausible datasets are then input to a 3D geological modeling engine to build a series of plausible alternative model realizations. Further processing may be applied to the series of plausible models to provide valuable decision aids such as probabilistic models, reliability models, or uncertainty reduction hotspot maps. In this paper, a complete and comprehensive MCUE procedure for common drillhole path and log uncertainty propagation is proposed. Basic concepts of drillhole uncertainty are introduced and are applied to a Markov Chain scheme. Appropriate disturbance distributions for the different parts of the problem and their respective parameterization are discussed. The method proposed is demonstrated on three separate proof of concept case studies of increasing complexity. Results demonstrate that the method is able to propagate path and log uncertainty appropriately. First order interpretation indicates that both path and log uncertainty increase with depth and angle of attack to the geological interfaces. Ignoring drillhole uncertainty was found to be detrimental to the understanding of a modeled area which is most likely due to the over-constraining effect brought by "perfect" drillholes. The third case study (Mansfield) hints that uncertainty is better reduced when drillholes intersect the "triple line" that partitions three distinct lithologies. In cross-sections, triples lines appear as triple points. Highlights • Propagation of uncertainty via MCUE for drillholes is a Markov Chain. • Drillhole induced model uncertainty increases with depth and distance to the drillhole path. • Uncertain drillholes may reduce overall model uncertainty. • Drillholes that intersect triple points/lines better reduce model uncertainty. • Low input uncertainty for drillhole retains significant impact on model uncertainty. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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36. Evaluating performances of green roofs for stormwater runoff mitigation in a high flood risk urban catchment.
- Author
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Ercolani, Giulia, Chiaradia, Enrico Antonio, Gandolfi, Claudio, Castelli, Fabio, and Masseroni, Daniele
- Subjects
- *
GREEN roofs , *RUNOFF , *GEOLOGICAL basins , *WATERSHEDS , *FLOOD risk , *PERFORMANCE evaluation - Abstract
Highlights • Evaluation of green roofs for stormwater management at urban basin scale. • Green roofs cause peak flow and volume reduction in the urban drainage network. • Green roofs are more effective during frequent storms of smaller magnitude. • Non-linear reduction of outlet peak flow if network mainly at maximum convey capacity. • Effectiveness may increase with spatially heterogeneous implementation. Abstract Urbanization modifies the hydrologic cycle, resulting in increased runoff rates, volumes, and peak flows in the drainage network. In this paper, the implementation of green roofs as source control solutions for mitigating the impacts of urbanization is analysed at the urban catchment scale. The hydrologic-hydraulic response of a 2 km2 urban basin is investigated under various implementation scenarios and rainfall characteristics. In particular, a distributed hydrologic model is employed to assess the impact of 4 spatially homogeneous installations of green roofs (25%, 50%, 75%, 100% of roofs area converted) when forced by 6 storms differing in both duration and return period. In addition, a spatially heterogeneous configuration is tested, with green roofs concentrated where the drainage network is more prone to high degrees of filling. Results show that implementing green roofs at the urban watershed scale can be considered a valuable strategy to reduce both flow peak and volume in urban drainage networks, although the approach is more effective for frequent storms of smaller magnitude. In addition, it is found that the urban system may respond non-linearly to the extent of green roofs implementation in terms of peak flow reduction at the network outlet, and that non-linearity is mainly related to the network being close to its flow convey capability. Finally, planning redevelopment efforts on the basis of local insufficiencies in network convey capacity has the potential of increasing the effectiveness of Low Impact Development solutions. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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37. The petrological control on the lithosphere-asthenosphere boundary (LAB) beneath ocean basins.
- Author
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Niu, Yaoling and Green, David H.
- Subjects
- *
LITHOSPHERE , *STRUCTURAL geology , *GEOLOGICAL basins , *PETROLOGY , *PERIDOTITE - Abstract
Abstract The plate tectonics theory established ~ 50 years ago has formed a solid framework for understanding how the earth works on all scales. In this theory, movement of the tectonic plates relative to the subjacent asthenosphere is one of the fundamental tenets. However, the nature of the boundary between the lithosphere and asthenosphere (LAB) beneath ocean basins remains under debate. The current consensus is that the oceanic lithosphere thickens with age by accreting asthenosphere material from below, and reaches its full thickness (L) of ~ 90 km at the age (t) of ~ 70 Ma. This lithospheric thickening fits the relation L ∝ t 1/2, consistent with conductive cooling to the seafloor. A puzzling observation is that although conductive cooling continues, the oceanic lithosphere ceases to grow any thicker than ~ 90 km when t > 70 Ma. Small scale convection close beneath the LAB has been generally invoked to explain this puzzle, but why such convection does not occur until L ~ 90 km at t > 70 Ma has been a matter of conjecture. In this paper, we summarize the results of many years of experimental petrology and petrological studies of oceanic basalts, which indicate consistently that the LAB is a petrological phase boundary marking the intersection of the geotherm with the solidus of amphibole (pargasite)-bearing peridotite. That is, petrologically, the LAB is an isotherm of ~ 1100 °C with L ∝ t 1/2 for t < 70 Ma and an isobar of ~ 3 GPa (~ 90 km) for t > 70 Ma. This unifying concept explains why the LAB depth increases with age for t < 70 Ma and maintains constant (~ 90 km) for t > 70 Ma. The LAB, that is intrinsically determined by petrological phase equilibria, does not require small-scale convection. However, because the mantle above the LAB is the conductive lithosphere (pargasite-bearing peridotite) and below the LAB is the viscosity-reduced convective asthenosphere (peridotite + incipient melt), the small-scale convection in the asthenosphere close beneath the LAB (~90 km) under older (t > 70 Ma) seafloors becomes possible, whose convective heat supply balances the conductive heat loss, maintaining the constant heat flow, seafloor depth and lithosphere thickness. Highlights • The lithosphere-asthenosphere boundary (LAB) beneath ocean basins is the dehydration solidus of pargasite (amphibole), whose stability defines the lithosphere with T ≤ ~ 1100°C, P ≤ ~ 3 GPa (~ 90 km) and H 2 O < 0.02 wt%; • The LAB is an isotherm with T ≈ 1100°C, whose depth L increases with age t , i.e., L α t 0.5 for t < ~ 70 Ma because of conductive cooling to the seafloor; • The LAB is an isobar at P ≈ 3 GPa (~ 90 km) for t > ~ 70 Ma, above which is the conductive lithosphere and below which is the convective asthenosphere, explaining why the lithosphere cannot grow any thicker when t > ~ 70 Ma and making sub-LAB convection possible. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
38. Crustal deformation and strain fields of the Weihe Basin and surrounding area of central China based on GPS observations and kinematic models.
- Author
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Qu, Wei, Lu, Zhong, Zhang, Qin, Wang, Qingliang, Hao, Ming, Zhu, Wu, and Qu, Feifei
- Subjects
- *
STRUCTURAL geology , *DEFORMATIONS (Mechanics) , *GEOLOGICAL basins , *GLOBAL Positioning System , *WENCHUAN Earthquake, China, 2008 , *STRAINS & stresses (Mechanics) - Abstract
Highlights • Explore characteristics of strain fields of Weihe basin region and surrounding areas. • Detect variations of differential motions within the region. • Illustrate variations of crustal strain fields through establishing sound kinematic models. • Discuss correlation between the maximum shear strain fields and the seismicity. • Reveal recent geodynamics processes of the region. Abstract The Weihe Basin in central China is characterized by its complex geological background and intense tectonic activity. This study examined the characteristics of the crustal deformation and strain field of the Weihe Basin and its surroundings based on campaign Global Positioning System (GPS) data acquired during 2001–2011. We first analyzed the variations of crustal movement and we calculated the crustal strain rates by establishing sound strain models. Both the characteristics of the strain field and the correlation between the maximum shear strain field and the distribution of seismicity were investigated. Our results indicated that the overall crustal movement of the Weihe Basin region was temporally continuous during 2001–2011, despite short-term fluctuation during 2007–2008. We found that western and eastern parts of the Weihe Basin region presented considerably different tectonic characteristics with predominantly compressional strain in the west and extensional strain in the east. However, the magnitude and direction of the overall crustal movement, and the relative differential motions of the Weihe Basin region, changed obviously during 2007–2008 with substantially increased compressional strain in western areas. We conclude that regions with higher shear strain are also those with frequent earthquakes, the distribution of which might have been affected by the M8.0 Wenchuan earthquake in May 2008. According to variations of the crustal deformation and the strain field, we further infer that western parts of the Weihe Basin region during 2007–2008 might have been affected by a northeastward extrusion caused by the Wenchuan earthquake. However, this dynamic effect might have gradually permeated to eastern parts of the Weihe Basin region during 2008–2011. The results obtained in this paper not only portray the current tectonic activity deformations but also the recent geodynamic processes of the Weihe Basin and its surrounding area. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
39. Regional flood frequency analysis using spatial proximity and basin characteristics: Quantile regression vs. parameter regression technique.
- Author
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Ahn, Kuk-Hyun and Palmer, Richard
- Subjects
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GEOLOGICAL basins , *FLOODS , *METEOROLOGICAL precipitation , *PREDICTION models , *GAGES - Abstract
Despite wide use of regression-based regional flood frequency analysis (RFFA) methods, the majority are based on either ordinary least squares (OLS) or generalized least squares (GLS). This paper proposes ‘spatial proximity’ based RFFA methods using the spatial lagged model (SLM) and spatial error model (SEM). The proposed methods are represented by two frameworks: the quantile regression technique (QRT) and parameter regression technique (PRT). The QRT develops prediction equations for flooding quantiles in average recurrence intervals (ARIs) of 2, 5, 10, 20, and 100 years whereas the PRT provides prediction of three parameters for the selected distribution. The proposed methods are tested using data incorporating 30 basin characteristics from 237 basins in Northeastern United States. Results show that generalized extreme value (GEV) distribution properly represents flood frequencies in the study gages. Also, basin area, stream network, and precipitation seasonality are found to be the most effective explanatory variables in prediction modeling by the QRT and PRT. ‘Spatial proximity’ based RFFA methods provide reliable flood quantile estimates compared to simpler methods. Compared to the QRT, the PRT may be recommended due to its accuracy and computational simplicity. The results presented in this paper may serve as one possible guidepost for hydrologists interested in flood analysis at ungaged sites. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
40. Tectonic units and proto-basin of the East China Sea Shelf Basin: correlation to Mesozoic subduction of the Palaeo-Pacific Plate.
- Author
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Yang, C. S., Li, S. Z., Li, G., Yang, C. Q., Yang, Y. Q., Dai, L. M., Suo, Y. H., Li, Q., and Jiang, Y. B.
- Subjects
- *
PLATE tectonics , *GEOLOGICAL basins , *MESOZOIC Era , *CENOZOIC Era , *SUBDUCTION , *PACIFIC Plate - Abstract
The East China Sea Shelf Basin (ECSSB) is a typical Meso-Cenozoic superimposed basin characterized by different tectonic frameworks, suffering multi-stage tectonism (e.g. the Indosinian, the Yanshanian and the Himalayan) since the Mesozoic. The Mesozoic ECSSB is a key place to our understanding of the tectonic evolution and dynamic mechanism in eastern South China and the subduction of the Izanagi Plate. Based on geological and geophysical results acquired over the last 10 years, this paper provides a summary of the distribution of Mesozoic strata, ascertains boundaries of the Mesozoic basin and proposes the division of the Mesozoic tectonic units in the ECSSB. The Mesozoic ECSSB was subdivided into the Western Fault Depression (WFD) characterized by dispersed Cretaceous half-grabens and the East Depression (ED) characterized by depressions at the early stage and grabens at the later stage. The WFD is composed of half-grabens formed under transtension, and the ED is composed of depression zones on the pre-Mesozoic basement under regional compression, indicating different dynamic mechanisms from the Cenozoic basins. Formation of the Mesozoic tectonic framework was controlled by the collision, compression and subduction of the Izanagi Plate and the Pacific Plate and also affected by the Indian Plate at a later stage. By comparison, this paper preliminarily proposes that the northern South China Sea and the ED of the ECSSB were originally a unified basin and jointly constituted a huge Mesozoic proto-basin in the East Asian continental margin. The Mesozoic tectonic unit division is helpful not only to discuss and resolve problems of ocean-continent differences and boundaries in southeastern South China but also to understand the tectonic nature of the East Asian continental margin, the dynamic mechanism of the Mesozoic basins and the transition of continental margin types. It also provides scientific support for petroleum exploration of the Mesozoic strata in the East China Sea. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
41. Cenozoic tectonic migration in the Bohai Bay Basin, East China.
- Author
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Zhao, Feiyu, Jiang, Suhua, Li, Sanzhong, Zhang, Huixuan, Wang, Gang, Lei, Jianping, and Gao, Song
- Subjects
- *
CENOZOIC Era , *PLATE tectonics , *SEDIMENTATION & deposition , *MAGMATISM , *GEOLOGICAL basins - Abstract
Tectonic migration is a common geological process during basin formation and development. However, there are many disputes about the tectonic migration and its dynamic mechanism in the Bohai Bay Basin. By analysis of Cenozoic tectonic, sedimentation and magmatism migration processes in the Bohai Bay Basin, combined with previous studies, the Cenozoic tectonic migration law in the Bohai Bay Basin is summarized in this paper. Affected by the subduction of the Indian Plate to the Eurasian Plate, its far-field effect of the related eastward asthenospheric extrusion and the subduction of the Pacific Plate to the Eurasian Plate, the Cenozoic Bohai Bay Basin is characterized by the gradual northeastward and eastward/seaward migration of tectonic units. The tectonic migration is accompanied by eastward migrations and younging of faulting, depressions in the Bohai Bay Basin, depocentres and subsidence centres and magmatism. Finally, based on intraplate and plate marginal processes and mechanisms, the tectonic migration mechanism in the Cenozoic Bohai Bay Basin is discussed in this paper. The gradual migration of tectonic-sedimentary-basin-forming movements is younger and younger towards the east, resulting from the combined effect of the collision and subduction among the Indian Plate and the Pacific Plate to the Eurasian Plate. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
42. The Eddy-Mean Flow Interaction and the Intrusion of Western Boundary Current into the South China Sea-Type Basin in an Idealized Model.
- Author
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Zhong, Linhao, Hua, Lijuan, and Luo, Dehai
- Subjects
- *
EDDIES , *OCEAN circulation , *OCEAN currents , *GEOLOGICAL basins , *VORTEX motion - Abstract
In this paper, an ideal model of the role of mesoscale eddies in the Kuroshio intruding into the South China Sea (SCS) is developed, which represents the northwestern Pacific and the SCS as two rectangular basins connected by a gap. In the case of considering only intrinsic ocean variability, a time-dependent western boundary current (WBC) driven by steady wind is modeled under both eddy-resolving and noneddy-resolving resolutions. Almost all simulated WBCs intrude into the adjacent sea in the form of the Loop Current with multiple-state transitions and eddy-shedding processes, which have aperiodic variations on intraseasonal or interannual scales, determined by the eddy-induced WBC variation. For the parameters considered in this paper, the WBC intrusion exhibits a 30-90-day cycle in the presence of the subgrid-scale eddy forcing (SSEF) but a 300-500-day cycle in the absence of SSEF. Moreover, the roles of the grid-scale and subgrid-scale eddies in the WBC intrusion are studied by using the dynamically consistent decomposition developed by Berloff. Based on the large-sample composite analysis of the intrusion events, it is found that the Loop Current intensity is mainly determined by baroclinic processes through grid-scale, eddy-eddy interaction and subgrid-scale, eddy-flow interaction. The intrusion position and period are mainly regulated by the SSEF to the west of gap, where the balance between relative vorticity and isopycnal thickness SSEFs determines eddy detachment. Generally, the relative vorticity SSEF therein tends to induce WBC intrusion. However, the isopycnal thickness SSEF tends to induce eddy shedding, and WBC retreat thus determines the intrusion cycle through counteracting relative vorticity SSEF. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
43. New Epipalaeolithic assemblages from the middle Euphrates and the implications for technological and settlement trends in the northeastern Levant.
- Author
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Kadowaki, Seiji and Nishiaki, Yoshihiro
- Subjects
- *
HUMAN settlements , *ARCHAEOLOGICAL assemblages , *RADIOCARBON dating , *GEOLOGICAL basins , *COMPARATIVE studies - Abstract
This paper concerns diachronic trends in human technological behaviors and settlements during the Early and Middle Epipalaeolithic periods in the northeastern Levant. The paper reconsiders a conventional view that links an increase in Epipalaeolithic settlements in the northeastern Levant to the archaeological entity called “Geometric Kebaran”. We re-examine the variability of the “Geometric Kebaran” assemblages in the northeastern Levant by adding two new microlithic assemblages (Wadi Kharar 16K and 16AT′) from the middle Euphrates region. On the basis of several techno-typological attributes of microliths, we suggest that the two assemblages represent two major techno-typological variants. The first group, including Wadi Kharar 16K, is characterized by large scalene triangles and truncations in association with the microburin technique, while the second group, represented by Wadi Kharar 16AT′, is dominated by trapeze-rectangles. We then discuss technological trends in the northeastern Levant in comparison with those in the southern Levant, where more comparative assemblages and radiocarbon dates are available. We argue that the group dominated by trapeze-rectangles in the northeastern Levant corresponds techno-typologically and chronologically to the Geometric Kebaran in the southern Levant. It is more difficult to specify which industry in the southern Levant is most similar to the group with scalene triangles and truncations in the northeastern Levant, but the latter group shows several techno-typological features that occur in the Early Epipalaeolithic in the southern Levant. Based on these chrono-cultural correlations between the northeastern and southern Levant, we suggest that Epipalaeolithic settlements started to increase in the northeastern Levant earlier than traditionally thought, i.e., before the appearance of the Geometric Kebaran. The proposed revision of the timing for the settlement intensification in the northeastern Levant significantly leads to a certain degree of parallel with a recent model of settlement dynamics in the southeastern Levant near the Azraq Basin. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
44. The Pan-African West Congo belt in the Republic of Congo (Congo Brazzaville): Stratigraphy of the Mayombe and West Congo Supergroups studied by detrital zircon geochronology.
- Author
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Affaton, Pascal, Kalsbeek, Feiko, Boudzoumou, Florent, Trompette, Roland, Thrane, Kristine, and Frei, Robert
- Subjects
- *
ZIRCON , *STRATIGRAPHIC geology , *YOMBE (Congolese & Angolan people) , *GEOLOGICAL time scales , *SEDIMENTARY basins , *GEOLOGICAL basins - Abstract
The African part of the Neoproterozoic Araçuai-West Congo orogen forms a more than 1400 km long belt, running from Gabon in the north to Angola in the south, parallel to the South Atlantic coast. It consists of the West Congo fold belt in the west and a largely undeformed sedimentary foreland basin in the east. In the Republic of Congo (Congo Brazzaville) these are known as, respectively, the ‘Mayombe fold belt’ and the ‘Niari basin’. The Mayombe fold belt is largely made up of strongly deformed metasedimentary rocks of the Mayombe Supergroup and its reworked granitoid basement complex. The Niari basin comprises the sedimentary strata of the West Congo Supergroup, which contain a unit of diamictite and associated cap-carbonate, related to the Marinoan (ca. 635 Ma) glaciation. In this paper detrital zircon U–Pb data are employed to investigate the relationships between the Mayombe and West Congo Supergroups in Congo Brazzaville, as well as the relationships with similar stratigraphic units in the Democratic Republic of Congo (DR Congo). Unfortunately, major differences in stratigraphical nomenclature exist between Congo Brazzaville and DR Congo which, together with geological differences, complicate comparisons. The terminology used in this paper follows the Congo Brazzaville tradition. U–Pb data have been obtained by LA-ICP-MS on 1674 zircon grains from samples of the Mayombe and West Congo Supergroups (seven and eight samples, respectively). Two of the samples have Palaeoproterozoic ages. The other samples are of Neoproterozoic age. Zircons from the latter fall into four main age groups: Group 1, 500–800 Ma, forming 8% of the total population; Group 2, 900–1200 Ma (29%); Group 3, 1800–2300 Ma (19%); and Group 4, 2500–3100 Ma (31%). Only ca. 13% of the zircons fall outside of these groups. Most zircons of Group 1 (600–800 Ma) are interpreted to have been derived from late Neoproterozoic magmatic arc rocks and syn- to post-collisional granites of the Araçuai orogen in Brazil, since rocks of these ages are rare in the Congo craton to the east. Most of Group 2 zircons have probably been derived from early Neoproterozoic (1000–900 Ma) rhyolitic and granitic rocks exposed in DR Congo. The Palaeoproterozoic and Archaean zircons of Groups 3 and 4 may have been derived both from eastern and western source regions. None of the stratigraphical units beneath the Marinoan diamictite contain the 500–800 Ma zircons of Group 1. This is interpreted to indicate deposition of these units during the earlier Neoproterozoic rift and drift phases in the history of the Araçuai-West Congo orogen, while the strata that do contain Group 1 zircons were deposited during the collisional phases and post-collisional uplift. A significant hiatus is likely to be present beneath the Marinoan diamictite. Based on these results, a revision of the stratigraphy of the Mayombe and West Congo Supergroups is recommended. Three granitoid rocks and two metasedimentary samples from the reworked basement complex have also been investigated, yielding Palaeoproterozoic ages, 2050–2100 Ma for the granites, and Palaeoproterozoic and Archaean detrital zircon ages for the metasedimentary rocks. Sm–Nd isotope data have been obtained on a number of (meta-)argilitic and siltstone samples. All samples yielded Palaeoproterozoic model ages, indicating mixing of sediments of different ages, as also observed in the zircon age distributions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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45. STATISTICAL ANALYSIS OF TEMPERATURE REGIME CHANGE ON THE EXAMPLE OF SOKOBANJA BASIN IN EASTERN SERBIA.
- Author
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RADIVOJEVIĆ, Aleksandar R., MARTIĆ BURSAĆ, Nataša M., GOCIĆ, Milena J., FILIPOVIĆ, Ivan M., PAVLOVIĆ, Mila A., RADOVANOVIĆ, Milan M., STRIČEVIĆ, Ljiljana S., and PUNIŠIĆ, Milan R.
- Subjects
- *
GLOBAL temperature changes , *ATMOSPHERIC temperature , *GEOLOGICAL basins , *METEOROLOGICAL stations , *STATISTICS - Abstract
The changes and oscillations in air temperature during the second half of the 20th and in the early 21st century, have become one of the major concerns of almost all scientific disciplines. Such changes are noticeable both at the local and global level. The objective of this paper is to point out that the changes of this climate element can also be detected at the local level. The research underlying this paper is, in terms of territory, limited to the Sokobanja basin in Eastern Serbia. The analysis relies on the data on air temperature for the period 1946-2012 taken from the Meteorological weather station located in Sokobanja. The obtained data were processed in line with the recommendations of the World Meteorological Organization. The evidenced statistically significant changes in air temperature were examined using the following statistical tests: Pettit test, Standard Normal Homogeneity test, Buishand range test, and von Neumann test. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
46. The Tatuí Formation (Early Permian, Paraná Basin), Brazil: Paleontology and Paleoenvironmental Considerations.
- Author
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Chahud, Artur and Petri, Setembrino
- Subjects
- *
PERMIAN Period , *GEOLOGICAL basins , *PALEONTOLOGY , *OUTCROPS (Geology) , *CONGLOMERATE - Abstract
The Tatuí Formation, one of the Brazilian Paraná Basin geological units, is developed solely in the State of São Paulo, southeast Brazil. It is studied herein, through outcrops at the eastern border of the basin, which are siltstones and fine sandstones, interbedded with some coarse and conglomeratic sandstones. Published papers on its fossils are sparse, dealing with some groups but not involving the entire association. This paper deals with ichnofossils, arthropods (conchostracans, isopods, and indeterminate crustaceans), plants (pteridophytes and spermatophytes) and fish remains (scales and teeth of Actinopterygii and Sarcopterygii). Foraminifers and sponge spicules were reported in short communications without illustrations and from uncertain stratigraphic positions. The Tatuí Formation paleoenvironmental deposition evolved through three phases. The first contains only the euryhaline fossils in siltstone beds. The second phase is regressive, with continental fossils (conchostracans and plants) in massive or laminated siltstone beds and conglomerates. The third stage is transgressive with hummocky cross - stratification in sandstone and increasing salinity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
47. Comparison of future runoff projections using Budyko framework and global hydrologic model: conceptual simplicity vs process complexity.
- Author
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Fernandez, Rodrigo and Takahiro Sayama
- Subjects
- *
HYDROLOGIC models , *RUNOFF models , *CLIMATE change , *SIMULATION methods & models , *GENERAL circulation model , *GEOLOGICAL basins - Abstract
This paper compared future runoff projections using a Budyko type equation with respect to projections by a global hydrological model (GHM). The comparison was made for the annual mean runoff projections for a future period (2060-2100) after the Budyko parameter was set based on hydrologic model outputs at a present period (1960-2000). The objective of this study was to investigate the performance of the Budyko equation with respect to the hydrologic model at different climate regions. To address the question this study used the spatial average of runoff for the 35 largest basins in the world. According to the comparison, the projections by the two approaches agreed well (R2 = 0.983), in particular in humid tropic region (R2 = 0.986), but with consistent underestimation of future runoff (Median Error, ME = -0.042) by the Budyko equation. In subarctic region the performance of the Budyko equation was low (R2 = 0.599) due to the overestimation of future runoff (ME = 0.110). The results in the dry and temperate regions also showed some discrepancy (R2 = 0.931 and 0.724) without apparent patterns in the errors. The paper discussed possible reasons for the errors with respect to water and energy seasonality and changes in storage component contributions. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
48. SPATIAL COMPLEXITY OF TRANSPORT INFRASTRUCTURE IN THE CZECH REPUBLIC.
- Author
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Tuček, Pavel, Rypka, Miroslav, Tučková, Michaela, Marek, Lukáš, Zajíčková, Lenka, and Burian, Jaroslav
- Subjects
- *
LANDSCAPES , *GEOLOGICAL basins , *MOUNTAINS , *HIGHWAY research , *STREETS - Abstract
The landscape of the Czech Republic is exceedingly varied. The country consists also river basins and low mountains and belongs to the small and midsize countries in Europe (78,866 km2). Transport of people and cargo is based mainly on roads, rails, air and inland waterways in the Czech Republic. Based on statistical evaluation, the most important type of transport (for both people and cargo) is road transport. The total length of road system in the Czech Republic is more than 55.000 km and is divided onto 5 main categories -- motorways, highways, roads of type I, II and III. According to the annual report of Czech Ministry of Transport, yearly performance of road transport is 73.28 bn. passenger km and 66.17 bn. tkm of cargo. The coverage density is one of the densest in Europe. The aim of the presented paper is to show a mathematically based approach how to evaluate the complexity of roads and streets with respect to geographical location of the studied cities. Fractal geometry and statistical evaluation of hypothesis testing were used for this purpose. The paper shows also the general overview of the methodology for complexity evaluation of networks. [ABSTRACT FROM AUTHOR]
- Published
- 2014
49. THE ANALYSIS OF GEODETICAL BASES USED IN ACHIEVEMENT OF UNDEGROUND MINING WORKS.
- Author
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Veres, Ioel and Filip, Larisa
- Subjects
- *
GEODESY , *TOPOGRAPHY , *MINES & mineral resources , *GEOLOGICAL basins , *MEASUREMENT errors - Abstract
Geodetic networks used in mining areas must be very accurate especially in situations where access in the underground is via two different locations positioned away from one another. Every place for access in the underground should have a basis for measurements, well determined as position and orientation in relation to the basis used at the other location for access in the underground. This requires that the design of geodetic networks on mining basin surface must find the optimal geometry of the network and the optimal schedule of topographic measurement, so that, the topographical bases that will be used in future for underground works to be well correlated relative to one another. This paper shows how the shape of network and measurement errors affect the results, namely the quality of the topographic bases. The paper also presents methods that can improve the quality of results. [ABSTRACT FROM AUTHOR]
- Published
- 2014
50. STUDY OF FLOOD WAVE PROPAGATION WITH HYDROINFORMATIC TOOLS.
- Author
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Beilicci, Erika, Beilicci, Robert, and Stefanescu, Camelia
- Subjects
- *
FLOOD risk , *GEOLOGICAL basins , *FLOODS , *MAPS , *FLOODPLAINS - Abstract
Water Framework Directive 2000/60/CE and Flood Directive 2007/60/CE establish the need for preparation of flood risk maps for each member country on each important hydrographic basins. Flood Directive requires Member States to assess if all water courses and coast lines are at risk from flooding, to map the flood extent and assets and humans at risk in these areas and to take adequate and coordinated measures to reduce this flood risk. This Directive shall be carried out in coordination with the Water Framework Directive, the flood risk management plans and river basin management plans must to be coordinated. To prepare flood risk maps need flood wave propagation study using hydroinformatic tools. In the last decades have taken a emergence of numerical tools for calculations, simulation and to the mapping in the domain of hydrodynamics, thanks to the computer technologies, the evolution of the programming languages and fast increment of processing speed. This paper presents the mathematical basis of two flood wave propagation simulation models, DUFLOW and MIKE11, and the comparison of these. The first model, DUFLOW, is a one-dimensional program for quantitative and qualitative modeling of water movement in open channels. The numerical methods offer multiple possibilities related to the most complex and difficult problems of research, developed in physics of hydraulic phenomena's. The numerical calculus permit the knowledge of physical phenomena's with sufficient accuracy, so most times, checking on laboratory models is no longer necessary. The second model, MIKE11, is a professional engineering software package for simulation of one-dimensional flows in estuaries, rivers, irrigation systems, channels and other water bodies. MIKE 11 is a 1-dimensional river model. The MIKE 11 is an implicit finite difference model for one dimensional unsteady flow computation and can be applied to looped networks and quasi-two dimensional flow simulation on floodplains. The model has been designed to perform detailed modeling of rivers, including special treatment of floodplains, road overtopping, culverts, gate openings and weirs. MIKE 11 is capable of using kinematic, diffusive or fully dynamic, vertically integrated mass and momentum equations. The paper contains also a case study, i.e. a flood wave propagation study for Crasna River, situated in north-western Romania, with the two hydroinformatic tools (DUFLOW and MIKE11) and results comparison. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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