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Es-Sbikhat- El-Mahmel, basin, located at the southeastern piedmont of Aures massif (Northeasten Algeria), is an area with a semi-arid climate. 39 samples were collected during May 2015, for physicochemical analysis. The interpretation of analysis data has shown a chemical facies evolution from bicarbonate-calcium waters into chloride-calcium waters, going through a transition facies marked by sulfate-calcium to sulfate-magnesium waters. The principal component analysis showed that the percentage of the variances expressed is 52.70% for the factor 1, 14.73% for the factor 2 and 11.44 for the factor 3. The binary diagrams and thermodynamic analysis corroborated that interaction water-rock is responsible for the mineralization through the geochemical process of mineral dissolution-precipitation, cationic exchange and anthropogenic pollution.

The impacts of climate change on the conjunctive use of surface water and groundwater resources of the Khorramabad basin were evaluated. Monthly temperature and rainfall modelled using HadCM3 and CGCM2 under greenhouse gas emissions scenarios (GHGESs) A2 and B2 were downscaled to baseline (1971–2000) and future periods (2040–2069 and 2070–2099). Simulations were performed for four climate change scenarios (CCSs) (A2-2040–2069, A2-2070–2099, B2-2040–2069 and B2-2070–2099). The projections indicated an increase in temperature and a decrease in rainfall. Future surface water resources were simulated using IHACRES. The results indicated that average annual runoff under GHGESs A2 and B2 would decrease by, respectively, 2.03% and 4.17% in 2040–2069 and by 6.64% and 8.94% in 2070–2099. Groundwater simulation was carried out using ModFlow. The results showed that under, the four CCSs, groundwater level would decline by 2.3, 3.0, 2.5 and 3.4%, respectively, relative to the baseline. Aquifer recharge under the four scenarios would decline by 1.43, 5.71, 2.86 and 7.14%, respectively. The results from IHACRES and ModFlow were employed to develop a conjunctive operation model with the Weap model. Several CCSs with various levels of future water demand were assessed using Weap. A 20% increase in water demand relative to the baseline, for instance, was projected to produce annual deficits in future agricultural water supply of 3.3, 5.08, 3.05 and 5.18 (× 106 m3), respectively, under the four CCSs.

Imperfect determination of petroleum system processes coincidence, entrapment and charge timing, along with reservoir heterogeneity can considerably cause high risks throughout exploration and development phases of petroleum. Therefore, a complete subsurface visualization of the petroleum system nature, elements and processes, is badly required. To this end, we corroborated, in this study, static reservoir modeling with petroleum system analysis workflows, to better characterize the Cenomanian fluvio-marine reservoir, sandstones of Bahariya Formation, at Bed-2 Field, Abu Gharadig basin (Western Desert, Egypt). We used dataset of 2D seismic profiles and well logs of eight wells. The geometry and property of the reservoir were acquired performing static reservoir geocellular modeling approach. The geohistory, timing of charge, migration pathways, and accumulation sites were identified performing 1D and 2D basin modeling approaches. Combining both approaches was aimed at identifying new petroleum prospect areas, and estimating the hydrocarbon volumes, that are the need for such poorly-defined petroleum systems area. As indicated by the constructed, robust, reservoir and 1D-2D basin models, an additional hydrocarbon prospect, to the north central part of Bed-2 Field, is proposed to be drilled during the further oilfield development phases of the area. This prospect has all features that adequately lead to reliable inferences regarding the ultimate petroleum potential of the area.

This paper discusses the results of siliceous microfossils studies performed in a “staircase” of four isolation basins (33.7 m–2.9 m a.s.l.) on Big Solovetskiy Island (Solovki Archipelago, the White Sea). Diatoms were used as a primary group for paleoinferences, while chrysophyte cysts and sponge spicules also demonstrated high indicative potential. In all study lakes, the siliceous microfossils stratigraphy revealed three main stages of their evolution, i.e. large-basin, transitional and small-lake stages, each characterized by certain composition of the diatom assemblages and floristic diversity, relative abundances of chrysophyte cysts and sponge spicules, and siliceous microfossils concentrations. In the uppermost lake, glaciolacustrine environments unfavorable for aquatic biota existed during the large-basin stage. The proglacial lake stage terminated prior to ca. 10.4 cal ka BP, followed by a (semi)terrestrial episode before the transition to small-lake environments. In the other three lakes, marine environments were inferred at the earlier stage, characterized by the predominance of marine and brackish-marine diatoms, increased proportions of sponge spicules and low “cysts to diatoms” ratio. At the transitional marine-freshwater stage, mass growth of small fragilarioid diatoms and decreased abundances of spicules indicated unstable environments, while increased proportions of cysts pointed to progressive freshening of the basins. The duration of the marine-freshwater transition expectedly prolonged from ca. 200 yr in the upper basin (16.6 m a.s.l) to ca. 500 yr in the lowermost lake (2.9 m a.s.l.). The isolation from the sea took place between ca. 6.3 and 1.4 cal ka BP. At the small-lake stage, siliceous microfossils stratigraphies reflected local specifics of the basins and their catchments. We argue that besides traditionally used diatom data, relative and absolute abundances of siliceous microfossils also possess high indicative value for isolation basin studies. Our study demonstrated that marine waters on Big Solovetskiy Island never reached ca. 34 m a.s.l. during the Holocene, unlike the western coast of the Onega Bay where the Preboreal marine intrusion was recorded even at higher elevated localities. Different rates and amplitudes of shoreline displacement are thus suggested for the inner and outer parts of the Onega Bay. During the mid-Holocene Tapes transgression, before ca. 6.3 cal ka BP, the relative sea level on Big Solovetskiy Island exceeded 17 m a.s.l. The average estimated rates of the shoreline retreat during the second half of the Holocene gradually decreased from 0.28 cm year−1 to 0.2 cm year−1, indicating slowed isostatic uplift.

Groundwater vulnerability maps by numerical methods help to set priorities for identifying areas that are most affected by pollutants, enabling decision makers, departments and government agencies to save additional funds in the event of a groundwater monitoring and protection system for the entire study area.Numerical methods as SINTACS and Modified DRASTIC with GIS technologies are depended in this study. SINTACS Vulnerability Index (SVI) is based on seven parameters while Modified DRASTIC Index (MDI) is based on eight parameters but both methods are adopted weighted sum overlay of the parameters. Final results of SINTACS Vulnerability map depicts four classes from very low to high which varies from (77 to 144). About 82.81% of study area is classified under moderate vulnerability; the remaining 15.08% and 1.75% are under high and low vulnerability respectively. MD- DRASTIC vulnerability map ranges (85–179). This range of index values is divided into four classes including very low to high vulnerability classes. About (72.35%) of the study basin has moderate vulnerability. High vulnerability measured as a second effective class of the studied area with (20.5%). While low and very low areas comprise (6.45% and 0.6%) respectively. Comparative study of two vulnerability maps with water quality data represented by nitrate concentration showed that MD- DRASTIC method is more suitable to represent the real reality of pollution of the area.

Data on the mineralogy and geochemistry of rare earth elements (REE + Y) in water, suspended matter and stratified sediment cores from different parts of Lake Onego are presented. The study finds that the dissolved REE + Y in the water from different areas of Lake Onego have common features: (1) a maximum in the area of middle rare earth elements (MREE), (2) a distinct negative Ce anomaly and (3) a positive Eu anomaly. Comparison of the average concentration of elements in the stratified core of the bottom sediments and particulate matter (from the filters and sedimentation traps) from different parts of Lake Onego and the distribution of REE + Y do not reveal any significant differences. The trend of the REE + Y distribution for samples from the South Onego completely coincide the REE + Y distribution in siltstones and sandstones of the Russian Platform Scale Composite (RPSC). In the water area of Lake Onego from south to north, a well-defined trend of changes in REE + Y patterns relative to the RPSC is revealed, with depletion by heavy REE + Y and gradual enrichment by light rare earth elements (LREE). Geochemical and mineralogical data confirm our hypothesis of a significant reformatting of the catchment basin of the Onego Ice Lake in the Late Pleistocene. During the formation of the preglacial lake, a significant part of the catchment area was located south of Lake Onego and is mainly represented by Russian Platform sedimentary rocks. Due to the degradation of the Last Glacier from the Lake Onego depression and the nearby territories, the catchment area changed of its southern and south-eastern sections. Today the composition of the modern sedimentary matter entering Lake Onego is determined by mixing clusters from two geochemically contrasting feeding areas: loose sediments formed by the repeatedly re-deposited products of the weathering of the Fennoscandian Shield's crystalline rock massifs, including Phanerozoic sediments; and to a lesser extent the sediments of the sedimentary cover of the Russian Platform, except the bottom sediments of the South Onego, in which Phanerozoic sedimentary formations have completely predominated throughout the lake's development.

The stock of shale gas in the Shahezi shale reservoir in the Changling fault depression, Songliao Basin, is believed to be worth exploring. In-depth study on the pore structure and fractal characterization of organic matter (OM) can help better understand the pore system of shale reservoir, which has implications for the exploration of lacustrine shale. To demonstrate the nanoscale pore structure and irregularity of the isolated OM, we collected a large number of samples and then conducted a series of laboratory experiments, such as X-ray diffraction, scanning electron microscopy, and [Formula: see text] and [Formula: see text] adsorption experiments to determine the pore structure parameters and reveal their heterogeneity according to Frenkel-Halsey-Hill theory. As suggested by the experimental results, the pore size distribution curve of the [Formula: see text] and [Formula: see text] exhibits similar pore peaks, whereas the trends of change in bulk shale and isolated OM samples are basically paralleled. The pore volume of the isolated OM ranges between 0.034 and [Formula: see text], which is approximately 0.90–3.06 times that of bulk shale samples. As for the fractal dimensions [Formula: see text] (2.594 on average) and [Formula: see text] (2.657 on average) of bulk shale, they are larger as compared with isolated OM, indicating that inorganic minerals can make a significant difference in the heterogeneity of shale pores. The fractal dimensions ([Formula: see text] and [Formula: see text]) of bulk shales indicate a close correlation with the parameters of pore structure, whereas there is no significant correlation observed between the dimensions of isolated OM and its parameters. In addition, thermal maturity and solid bitumen have only limited impact on the OM pore structure of isolated OM samples. Then, we conducted further research to reveal that the insoluble OM macerals derived from terrestrial higher plants can be used to explain the difference in pore structure and heterogeneity between isolated OM samples. Therefore, we arrived at the conclusion that the composition of macerals depends on the exact pore structure and fractal characteristics of isolated OM samples with similarity in thermal maturity.

Ephemeral fluvial systems in the dryland region of Kachchh are susceptible to climatic fluctuations. An increase in Indian Summer Monsoon Intensity (ISM) is responsible for the aggradation of sediments as valley-fill deposits in the river basins. In the present study sedimentological, chronometric, and geochemical analysis on the fluvial terrace sequences of Nirona and Bhukhi river basins are being used to interpret southwest summer monsoon variability from MIS 5D-5C along with the fluvial response to local tectonics. The sediment record indicates increased ISM precipitation from ∼110ka to ∼90ka, which corresponds to the MIS 5D to MIS 5C (Interstadial stage). The ISM became progressively weaker during the MIS-5B (stadial stage), leading to present-day arid conditions. The climatic factors weakened along with an interplay of local tectonics, leading to present-day conditions of bedrock incision.

This paper presents a summary of work undertaken by the authors and their teams on a series of Qe'an (plural of Qa’), in the Badia of eastern Jordan. These basins are foci for settlement in the region, with the sites described here (Shubayqa, Wisad and the Qa’ Qattafi) edged by archaeological sites dating from the late Epipalaeolithic (ca. 14,500 - 11,600 cal BP) and the Neolithic (ca. 11,700 - 6100 cal BP), and in areas still used by people today as seasonal wetlands for watering animals and growing cereal. We assess here the potential for the Qe'an sediments to provide what would be rare continuous palaeoenvironmental records for this part of SW Asia.\ud \ud The paper presents the first dates from the Qe'an of this region and the outline sedimentology. Much of the fill is of Holocene age, which leads to discussion of climate and landscape change over the last 15,000 years, particularly due to the close geographical relationship between these basins and archaeology. Our optically stimulated luminescence and radiocarbon dating of the basin fill suggests that there was significantly more space in the landscape for water storage in the early Holocene, which may have therefore provided this resource for people and their livestock or game for a longer duration each year than that seen today. Linked to this are hypotheses of a more vegetated landscape during this time period. Given the environmentally marginal nature of our study area subtle changes in landscape and/or climate, and human exploitation of these resources, could have led to significant, and likely detrimental for its inhabitants, environmental impacts for the region, such as desertification. Our data are suggestive of desertification occurring, and sets up a clear hypothesis for testing by future work in the region.

Tight sandstone reservoirs are widely developed in the Mesozoic Yanchang Formation of the Ordos Basin, China. There is a lack of understanding on the sedimentary setting, source-reservoir relationship and oil accumulation conditions in this area. In this study, through the comprehensive analysis of the distribution of tight oil, we evaluated the properties and petrological features of reservoir, geochemical characteristics of source rocks, the source-reservoir relationship, as well as the trapping, preservation and accumulation conditions of tight oil in the Chang 7 Member, and predicted the sweet spots of tight oil in the study area. The results show that the Chang 7 Member is a typical low-porosity and ultra-low permeability reservoir with great tightness, small pore throat and high capillary pressure, and must have been of near-source accumulation. The source rocks are mainly developed in the Chang 73 submember, and the reservoirs mainly occur in the Chang 71 and Chang 72 submembers, forming a combination mode of “lower source rock and upper reservoir”. Sandbodies with good connectivity and fractures being well developed in local areas are the main hydrocarbon transport systems. The abnormal high pressure caused by hydrocarbon generation and pressurization is the main driving force of tight oil accumulation. The mode of hydrocarbon transportation is dominated by the vertical or lateral migration from underlying source rocks or adjacent source rocks to reservoirs within a short distance. Following the integrated evaluation of lithology, physical properties and oil saturation of reservoirs and geochemical characteristics of source rocks, we grouped the sweet spots of Chang 7 Member into three types: Type I, Type II and Type III. Among others, the Type I sweet spots are the best in terms of porosity, permeability and source rock thickness and hydrocarbon enrichment which should be the focus of oilfield development. This study lays an important foundation for the economic and efficient development of tight oil in the Chang 7 Member of Heshui area, and has important implications on tight sandstone reservoirs in other regions of Ordos Basin in China.

Several sets of Paleozoic tight reservoirs are developed in the Central Uplift of the South Yellow Sea Basin. A qualitative analysis of the microscopic pore structure of the tight reservoir rocks was carried out through cast thin slice and scanning electron microscopic image observation. Based on reservoir petrophysical properties, thirty core samples in the Central Uplift of the South Yellow Sea Basin were selected for high-pressure mercury intrusion (HPMI) analysis, which was then combined with fractal calculation to classify and evaluate the tight reservoirs. The analysis of the HPMI curves and related parameters shows that the Paleozoic tight reservoirs can be divided into three types: Type-A, Type-B and Type-C. Type-A sandstone reservoirs contain pores with size mostly ranging between 0.01 and 0.1 μm, followed by pores with size range of 0.001–0.01 μm, and relatively fewer pores larger than 0.1 μm. The Type-B reservoirs are carbonate rocks with extremely heterogeneous pore size distribution, which is closely related to the development of dissolution pores and microfractures. Type-C sandstone reservoirs are dominated by nanopores and submicron pores that distribute more heterogeneously than pores in Type-A reservoirs. The pore distribution in sandstone reservoirs shows significant fractal characteristics and is closely related to the pore size. The heterogeneity of nanopore distribution has a negative correlation with porosity and median pressure and a relatively weak correlation with permeability. Our study has important implications for petroleum exploration in the South Yellow Sea Basin.

In recent years, the discovery of the Jurassic oil reservoirs in the Western Thrust Belt of the Ordos Basin reveals that the Jurassic formation in this area has huge oil and gas potential. The pre-Jurassic paleogeomorphology plays a vital role in the formation of the Jurassic oil reservoirs. In this paper, the impression method is applied to restore the pre-Jurassic paleogeomorphology of the Hongde area in the western Ordos Basin, using a large number of drilling, logging, well testing and the latest 3D seismic data. The pre-Jurassic paleogeomorphological units in the study area can be categorized into five groups, including ancient channel valley, ancient terrace, slope, interchannel mound, and low residual mound facies. The oil reservoirs are mainly distributed in highland areas such as slope belts and low residual mounds, the main areas where hydrocarbons accumulate. In addition, the branch ditches in the study area are developed to the southeast and merged into the Ganshan ancient channel. The sandstone in the confluence area of the branch gully is well sorted and connected under frequent scouring by the river. The sand bodies of good connectivity therefore form a drainage system for long-term hydrocarbon migration. The formation of the Jurassic reservoirs in the study area is mainly affected by sedimentary facies, deposition location, and hydrocarbon migration pathway (or fault) of pre-Jurassic paleomorphology. The results from this study can be useful for the prediction of the Jurassic sweet spots in the western margin of the Ordos Basin.

The Azraq oasis in the Eastern Desert of Jordan has produced considerable stone artefacts attributed to the early Palaeolithic, yet relatively few data are available regarding the chronology and palaeoenvironmental contexts of the remains. In this study, we present stratigraphic, sedimentological, and micropalaeontological analyses of the Late Acheulean site SM1 located within the former Shishan Marsh, which we combine with geochronological and sedimentological data from 13 neighbouring geological exposures to reconstruct landscape evolution at the western margin of the Shishan Marsh. We then discuss the Late Quaternary palaeolandscapes of the Greater Azraq Oasis Area over the past c. 350 ka. Our work demonstrates that the central Azraq Basin experienced three local wetting-drying cycles since the late Middle Pleistocene that would have dramatically shifted the quantity and distribution of freshwater resources, ranging from expansive wetland landscapes to desert refugia characterised by isolated spring pools—changes that would have significantly impacted the mobility decisions and settlement patterns of Palaeolithic inhabitants. Our study highlights that developing long-term records of human-environment dynamics in arid environments requires a mosaic approach to palaeoenvironmental reconstruction that is nested within a well-developed understanding of landscape evolution.

Neogene fossil records from the Indus Basin sedimentary rocks (IBSR), deposited in the Indus Tsangpo Suture Zone (ITSZ), are very rare, but are important to understand the history of plant diversity and paleoclimate in the Himalaya. We report fossil wood ascribed to Ebenoxylon siwalicus Prakash from late Miocene sediments of the Karit Formation belonging to ITSZ. The anatomical details of the fossil wood, such as small to medium-sized vessels occluded with tyloses, scanty paratracheal to diffuse-in-aggregate axial parenchyma, 1–3 seriate homo to heterocellular xylem rays, bordered intervessel pits with lenticular apertures and simple perforations, suggest its close affinity with Diospyros Linnaeus of the family Ebenaceae. Further anatomical details suggest a close resemblance with extant D. ehretioides Don and D. macrophylla Blume. The present fossil, along with previously known fossil records of Lagerstroemia (Lythraceae) and palms, indicate that the Trans-Himalaya was warm and humid during the late Miocene, quite different from the modern cool and dry climate in the study area.

Radium isotopes have been used to trace nutrient, carbon, and trace metal fluxes inputs from ocean margins. However, these approaches require a full accounting of radium sources to the coastal ocean including rivers. Here, we aim to quantify river radium inputs into the Arctic Ocean for the first time for 226Ra and to refine the estimates for 228Ra. Using new and existing data, we find that the estimated combined (dissolved plus desorbed) annual 226Ra and 228Ra fluxes to the Arctic Ocean are [7.0–9.4] × 1014 dpm y−1 and [15–18] × 1014 dpm y−1, respectively. Of these totals, 44% and 60% of the river 226Ra and 228Ra, respectively are from suspended sediment desorption, which were estimated from laboratory incubation experiments. Using Ra isotope data from 20 major rivers around the world, we derived global annual 226Ra and 228Ra fluxes of [7.4–17] × 1015 and [15–27] × 1015 dpm y−1, respectively. As climate change spurs rapid Arctic warming, hydrological cycles are intensifying and coastal ice cover and permafrost are diminishing. These river radium inputs to the Arctic Ocean will serve as a valuable baseline as we attempt to understand the changes that warming temperatures are having on fluxes of biogeochemically important elements to the Arctic coastal zone.

Although liverworts are widely distributed around the world with a large number of extant species, reliable fossil records are relatively rare. Here, we report a new species, Ricciopsis baojishanensis Han and Yan, n. sp. (Ricciaceae) and an unnamed species, Hepaticites sp. from the Late Triassic Nanying’er Formation in Baojishan Basin, Baiyin City, Gansu Province, Northwest China. The generic designation is based on detailed comparison of the gross morphology with related fossil and extant species. The new species is characterized by its rosette-forming thallus, dichotomous branching, ribbon-like segments and entire margins. The current fossils represent the first record of liverwort from the Late Triassic in Baojishan Basin, Gansu Province. Based on the different fossil records of the Ricciaceae, we suggest that these taxa were widely distributed during Late Triassic to Oligocene worldwide, mainly in warm temperate and tropical environments, similar with their current distribution. The discovery of the present fossils indicates that the climate of Baojishan Basin in Late Triassic is warmer and more humid than that of today.

We present the results of geochemical investigations, including stable isotope, of the Eemian (MIS 5e) and Vistulian (Weichselian, MIS 5a–d, MIS 3–4) sediments of the palaeolake horizons from Gorzow Wielkopolski site (NW Poland). Our analyzes comprised two profiles from different parts of lake basin, each approximately 11-m long. The deposits represent two cycles of lake accumulation (two limnic layers), each ended by peat deposition, separated by mineral fluvial deposits. The lower and upper limnic layers, despite several similar geochemical features, are records of two separate phases of the lake's functioning. The palynological data suggest that the mineral deposits separating them are not continuous succession, but contain a stratigraphic hiatus. We characterized six geochemical zones (GZ), which correspond well with lithological features of deposits and climatic changes, and reflect the changing environmental conditions (redox conditions, variability and intensity of denudation, biological productivity, and fertility of the environment). In the first phase of lake's development, some influence of the surface material supply is visible, indicated by the increased content of lithophilous elements, (e.g. potassium), as well as closely correlated with them copper and zinc. Slow accumulation of carbonates dominated the limnic layers due to their abundant supply from the catchment area. The greatest variations of isotopic values of carbonates occur in the bottom and at the top of the stratigraphic profile and are related to the changing environmental conditions in the lake's basin (water level and temperature variations). The differences in carbon and nitrogen isotope values suggest different sources of organic matter accumulated in the studied basin and varying trophy of the environment. The higher mercury content is related to the course of climate change and is the highest in cold periods. We identified five main phases of evolution of the palaeolake at Gorzow Wielkopolski site. The lake accumulation began during the final phase of the Wartanian (Late Saalian) Glaciation (MIS 6). Initially the palaeolake harmonically developed and reached its maximum depth (Early and Middle Eemian, MIS 5e). Next the palaeolake became shallower and transformed into the peatbog (Late Eemian, MIS 5e). In the Early Vistulian period (or Early Weichselian, MIS 5a–d), the lake re-existed, initially as a flow-through lake. Finally in middle Vistulian (or Middle Weichselian – Pleniglacial, MIS 3–4), the palaeolake declined and mire developed.

Piggyback basins are common and well-studied features of thrust belts, but they are also known to form in front of advancing ice sheets. However, these glacitectonically developed basins and their syn-glacitectonic fillings have so far received little attention. Here, we present a detailed study of a cliff section on Jasmund peninsula, SW Baltic Sea, where syn-kinematic deposits of Late Weichselian age (MIS2) accumulated in a piggyback basin. Sedimentological analyses, including micromorphology and field studies, resulted in a distinction of at least five tectono-depositional sequences of syn-glacitectonic basin fills. The sediment record indicates a stepwise evolution of the basin, controlled by propagating thrust faults and the resulting thrust-bound ridge morphology. A fast-changing depositional environment with glacifluvial, glacilacustrine, alluvial fan and fan delta depositional systems, show a rapid transformation of the overall morphology of the study area. The main controlling factors are the propagating thrust faults (determining anticline and syncline orientations) and the advancing ice margin, which caused sudden changes or even temporal obstruction of the meltwater drainage system. The proposed stages of basin evolution illustrate the dynamic formation and stepwise syn-tectonic fill of piggyback basins in glacitectonic complexes. Our evolutionary model will increase our understanding of basin fills on glacitectonic thrust- and fold-belts that were formed by approaching ice sheets in ice-marginal settings.

We present a multiproxy record of grain size and stable carbon isotope from the Lilaur lake, Ganga Basin, India to understand the history of lake formation linked to changes in Indian monsoon precipitation during ~13714 to 3073 calibrated year before Present (cal yr BP). A comparison is made between Lilaur lake proxy record with those from other parts of South Asia as well as North Atlantic to understand extent and causes of monsoon variability and its influence on the fauna and flora of the region. Chronology of lake core was constrained using AMS 14C and optically stimulated luminescence (OSL) dates. This study suggests a transition from river to lake during ~5800 to 5189 cal yr BP which is supported by reduced precipitation with weakening of the Indian summer monsoon (ISM). This river to lake transition culminated in a severe arid phase during 4250 to 4050 cal yr BP (4.2 ka event), corresponding to enhanced El Nino activity, southward shift of the Inter-Tropical Convergence Zone, and aridification of India when the ISM was weak.

High-resolution multichannel seismic data and multibeam terrain data are used to analyse and identify a focused fluid flow (FFF) system in the central and northern parts of the Zhongjiannan Basin in the western South China Sea. The authors classify and summarise the geophysical characteristics of an FFF system in the study area. It is divided into a fault-related FFF system and a column-related FFF system. In addition, the FFF system in the study area is mainly located within the tectonic activity area, thin slope break belt and land slope area. The rich FFF system in the study area is an important channel for fluid migration, which is conducive to gas hydrate accumulation. The FFF system in the study area is poorly studied, and the distribution research results of the FFF system in this area can be used more widely in hydrocarbon and gas hydrate exploration and must be taken into account when assessing seabed stability.

The Lancang–Mekong River (LMR) is an important transboundary river that originates from the Tibetan plateau, China and flows through six nations in Southeast Asia. Knowledge about the past and future changes in climate and water for this basin is critical in order to support regional sustainable development. This paper presents a comprehensive review of the scientific progress that has been made in understanding the changing climate and water systems, and discusses outstanding challenges and future research opportunities. The existing literature suggests that: ① the warming rate in the Lancang–Mekong River basin (LMRB) is higher than the mean global warming rate, and it is higher in its upper portion, the Lancang River basin (LRB), than in its lower portion, the Mekong River basin (MRB); ② historical precipitation has increased over the LMRB, particularly from 1981 to 2010, as the wet season became wetter in the entire basin, while the dry season became wetter in the LRB but drier in the MRB; ③ in the past, streamflow increased in the LRB but slightly decreased in the MRB, and increases in streamflow are projected for the future in the LMRB; and ④ historical streamflow increased in the dry season but decreased in the wet season from 1960 to 2010, while a slight increase is projected during the wet season. Four research directions are identified as follows: ① investigation of the impacts of dams on river flow and local communities; ② implementation of a novel water–energy–food–ecology (WEFE) nexus; ③ integration of groundwater and human health management with water resource assessment and management; and ④ strengthening of transboundary collaboration in order to address sustainable development goals (SDGs).

We here report a high-resolution organic C-isotope record from terrestrial–marine transitional sediments of the Badong Formation in the Luojiagou section, Zigui Basin of Hubei Province, South China. Our organic carbon isotope (δ13Corg) profile, ranging from -21.2‰ to -26.2‰, shows four negative carbon-isotope shifts. We suggest that the sharpest negative carbon isotope excursion in the upper portion of the Badong Formation marks the main phase of the Carnian Pluvial Episode (CPE) in the basin, likely correlated with those in other depositional records of this time. The occurrence of the CPE in the Badong Formation would imply that the stratigraphic coverage of the Badong Formation might be prolonged to incorporate (at least part of) the Late Triassic Carnian stage. This result provides a potential case for understanding the CPE in continental–marine environments in the eastern Tethys realm, and is significant for exploring the palaeoclimate variation across the Late Triassic.

Abkenar open water (AOW) has a 35 km2 distribution and is the largest part of the Anzali Lagoon in the southern coastal zone of the Caspian Sea. The effects of deforestation in the upstream basin of the AOW were assessed by measuring the rate of sedimentation, sediment contamination, and ecological risk for aquatic life and end-users using radioisotopes Cesium-137 and Lead-210. The chronology of the AOW sediment column was studied using the Constant Rate of Supply model. Correlations between environmental changes and the sedimentary regime of the study area highlight the contribution of the AOW authorized international and local wood harvesting companies pre-and-post 1950 in the catchment in terms of the rate of sediment supply and the influx of toxic metals. Historical evidence shows that two specific layers formed during World Wars I and II with the mean rates of 0.185 ± 0.04 (±STD) and 0.32 ± 0.02 kg/(m·y), respectively. The highest influx of alkali elements and toxic metals (nickel, cadmium, lead, zinc, and copper) into the basin occurred in 1945. Two layers of gray mud (16–50 cm) and organic-rich dark loss mud (0–16 cm) correlated well with the programmed wood harvesting projects. These layers accumulated from 1953 to 2000 with a mean rate of 0.6 ± 0.2 and 2 ± 0.7 kg/(m2·y). Thus, aquatic life and end-users have been exposed to moderate to extremely high levels of toxic metals and a moderate level of contamination since the 1950s.

Using observations and numerical simulations, this study examines the intraseasonal variability of the surface zonal current (u ISV) over the equatorial Indian Ocean, highlighting the seasonal and spatial differences, and the causes of the differences. Large-amplitude u ISV occurs in the eastern basin at around 80°–90°E and near the western boundary at 45°–55°E. In the eastern basin, the u ISV is mainly caused by the atmospheric intraseasonal oscillations (ISOs), which explains 91% of the standard deviation of the total u ISV. Further analysis suggests that it takes less than ten days for the intraseasonal zonal wind stress to generate the u ISV through the directly forced Kelvin and Rossby waves. Driven by the stronger zonal wind stress associated with the Indian summer monsoon ISO (MISO), the eastern u ISV in boreal summer (May to October) is about 1.5 times larger than that in boreal winter (November to April). In the western basin, both the atmospheric ISOs and the oceanic internal instabilities contribute substantially to the u ISV, and induce stronger u ISV in boreal summer. Energy budget analysis suggests that the mean flow converts energy to the intraseasonal current mainly through barotropic instabilities.

The sediments of glacial lakes in the eastern Sierra Nevada (California, USA) hold promise as archives of hydroclimatic and ecological changes, which has implications for understanding California's water supply. Here we present the initial results of a compressed high intensity radar pulse (CHIRP) seismic reflection survey of Convict Lake, a small, hydrologically open terminal moraine lake in the Sherwin Range of northeastern California. These 0.5–8.0 kHz CHIRP profiles represent the first acoustic images of the subsurface of Convict Lake. The sublacustrine geomorphology of Convict Lake is defined by a dominantly flat floored deepwater depocenter that reaches a maximum depth of ~44 m. Seismic reflections over most of the depocenter are moderate amplitude, coherent, and continuous, consistent with hemipelagic sedimentation of silt-sized allochthonous particles and organic matter. The ice-sculpted lateral margins of the basin are steep and prone to mass wasting, as shown by discontinuous and chaotic reflections organized into convex lenses or irregular mounds on the lake floor. The southwestern axial margin is a sand-dominated deltaic ramp formed by the inflowing Convict Creek, whereas the northeastern axis is rocky littoral ramp that shoals toward the basin outlet and accumulates minimal lacustrine sediment. In areas unobscured by gas curtaining, the CHIRP data reveal an asymmetric basin fill that expands subtly to the southeast, reaching a maximum thickness of ~19 m s two-way travel time. The basin fill consists of three seismic stratigraphic units. Onlap and truncation geometries separating the seismic units indicate that lake level changes likely played an important role in shaping the stratigraphy of Convict Lake. Seismic profiling at Convict Lake is the critical first step towards placing the lake and its depositional record into the late Quaternary environmental history of the Convict Creek Valley.

The Nihewan Basin is one of the most important areas for the study of early human evolution and land mammals in East Asia. More than 100 Paleolithic sites have been discovered in the basin, spanning the Early Pleistocene to the Late Pleistocene. The chronological framework for the Early Pleistocene sites is well established using magnetostratigraphy. However, few independent ages are associated with Middle Pleistocene sites; one such example is the Hougou Paleolithic site, where interpolated magnetostratigraphic ages are not precise and accurate enough, owing to the artifact layer of the site is far relative to the Matuyama/Brunhens (M/B) boundary. In this study, we use the ESR signals of Al and Ti–Li centers in quartz to date the Hougou site. The advantages of the regenerative dose method over the additive dose method were discussed. Our ESR results indicate that the age of the Hougou Paleolithic site is between 436 ± 30 and 416 ± 42 ka, approximately with an average of 426 ± 36 ka, which corresponds to Marine Isotope Stage (MIS) 12 or loess layer L5. In addition, the disappearance time of the eastern part of the Nihewan paleolake may be approximately 430 ka.

Commonly, intra-continental wrenching is associated with a high degree of crustal faulting and fragmentation. The resulting continental blocks can undergo vertical-axis rotations, which in turn can lead to the generation of intricate fault networks within and along their boundary regions. Investigations into these structural complexities can support understanding of when and how these continental blocks rotate, and what their position was prior to transform margin formation. In the case of the Falkland Islands Microplate (part of the Falkland Plateau transform margin), its position between South Africa, South America, and East Antarctica prior to the break-up of Gondwana is still debatable. This uncertainty affects the reliability of plate models for this region. Here we integrate gravity and 2D and 3D seismic reflection data from the eastern margin of the microplate (west side of the Falkland Plateau Basin) to provide insights into the tectono-stratigraphic architecture of this area from Jurassic onwards, and into the evolution of the Falkland Islands Microplate. Our findings show that the western part of the Falkland Plateau Basin is an integral part of the microplate, and it underwent deformation in a relatively fast-changing stress regime. Stress field configuration estimates across the Falkland Islands Microplate support an alternation between a NE-SW and NW-SE/WNW-ESE orientation of σ3 during the Jurassic and an ENE-WSW oriented σ3 during the Lower Cretaceous. Correlations of this local stress configuration with the regional support a Middle to Upper Jurassic rotation of the microplate in a predominantly extensional setting facilitated by the early fragmentation of south-western Gondwana.

Deep water in the South China Sea is renewed by the cold and dense Luzon Strait overflow. However, from where and how the deep water upwells is poorly understood yet. Based on the Hybrid Coordinate Ocean Model reanalysis data, vertical velocity is derived to answer these questions. Domain-integrated vertical velocity is of two maxima, one in the shallow water and the other at depth, and separated by a layer of minimum at the bottom of the thermocline. Further analysis shows that this two-segmented vertical transport is attributed to the vertical compensation of subsurface water to the excessive outflow of shallow water and upward push of the dense Luzon Strait overflow, respectively. In the abyssal basin, the vertical transport increases upward from zero at the depth of 3 500–4 000 m and reaches a maximum of 1.5×106 m3/s at about 1 500 m. Deep water upwells mainly from the northeastern and southwestern ends of the abyssal basin and off the continental slopes. To explain the upward velocity arising from slope breaks, a possible mechanism is proposed that an onshore velocity component can be derived from the deep western boundary current above steep slopes under bottom friction.

The purpose of this study is to investigate the entire evolution process of shales with various total organic contents (TOC) in order to build models for quantitative evaluation of oil and gas yields and establish methods for assessing recoverable oil and gas resources from in-situ conversion of organic matters in shale. Thermal simulation experiments under in-situ conversion conditions were conducted on Chang 73 shales from the Ordos Basin in a semi-open system with large capacity. The results showed that TOC and Ro were the key factors affecting the in-situ transformation potential of shale. The remaining oil and gas yields increased linearly with TOC but inconsistently with Ro. Ro ranged 0.75%–1.25% and 1.05%–2.3%, respectively, corresponding to the main oil generation stage and gas generation stage of shale in-situ transformation. Thus a model to evaluate the remaining oil/gas yield with TOC and Ro was obtained. The TOC of shale suitable for in-situ conversion should be greater than 6%, whereas its Ro should be less than 1.0%. Shales with 0.75% (Ro) could obtain the best economic benefit. The results provided a theoretical basis and evaluation methodology for predicting the hydrocarbon resources from in-situ conversion of shale and for the identification of the optimum “sweet spots”. The assessment of the Chang 73 shale in the Ordos Basin indicated that the recoverable oil and gas resources from in-situ conversion of organic matters in shale are substantial, with oil and gas resources reaching approximately 450×108 t and 30×1012 m3, respectively, from an area of 4.27×104 km2.

Within the sediments of the Pyrzyce Ice-dammed Lake (Polish Lowlands), a number of soft-sediment deformation structures (SSDS) in varve series were distinguished. The unique morphology of the ice-dammed lake—the occurrence of level IV overload and the presence of dead ice in the central zone (Lake Miedwie) and the marginal reservoir—had a decisive impact on the formation and nature of sedimentary structures. Dead ice melting and loss of support could be the cause of plastic deformation. The highest intensity deformation in layered sediments of both plastic and rigid types was observed in the marginal (highest) part of the reservoir. Their formation is associated with the melting of rooted lumps of dead ice in sub-aquatic conditions. The exception is deformation resulting from desiccation under subaerial conditions. The genesis of the deformation observed in rhythmically-layered varves is associated with the last stage of functioning and disappearance of the reservoir during the recession of an ice sheet of the Pomeranian phase of the Weichselian glaciation. These studies detail the current state of knowledge on the processes and factors responsible for the formation of soft structures occurring in glaciolimnic basin.

Coregonine fishes are important to Laurentian Great Lakes food webs and fisheries and are central to basin-wide conservation initiatives. In Lake Ontario, binational management objectives include conserving and restoring spawning stocks of cisco (Coregonus artedi) and lake whitefish (C. clupeaformis), but the spatial extent of contemporary coregonine spawning habitat and the environmental factors regulating early life success are not well characterized. In Spring 2018, we conducted a binational ichthyoplankton assessment to describe the spatial extent of coregonine spawning habitat across Lake Ontario. We then quantified the relative importance of a suite of biophysical variables hypothesized to influence coregonine early life success using generalized additive mixed models and multimodel inference. Between April 10 and May 14, we conducted 1,092 ichthyoplankton tows and captured 2,350+ coregonine larvae across 17 sampling areas, predominantly within embayments. Although 95% of catches were in the eastern basin, coregonine larvae were also found in historical south shore spawning areas. Most coregonine larvae were cisco

In the present study, based on faunistic information collected during 2014 and 2015, in association with physical–chemical conditions of the collection sites, the environmental factors influencing the composition and distribution of chironomid assemblages were investigated. In total, 164 Chironomidae taxa reported in this study extended the existing checklist with 152 taxa newly found in the Skadar Lake basin. The comparison based on the list of species from the six large, well-studied European lakes showed that Lake Constance (Switzerland/Germany/Austria) is the most species-rich waterbody with 174 taxa, followed by Lake Skadar with 164 taxa. For pupal exuviae, the most species-rich site was situated in the centre of the small lake (north-western part of the Skadar Lake). A Canonical Correspondence Analysis (CCA) revealed that shallow coastal parts of the lake are much richer in species than the open, deeper parts of the lake. This first investigation since 1979 of non-biting midge species (including imagines) diversity will help to monitor biodiversity of the basin and to understand how protection programs influence biodiversity within the lake basin.

In the current research, the impact of the COVID-19 lockdown period on sediment quality of the Meric-Ergene River Basin was evaluated by determining the potentially toxic elements (PTEs) in sediment samples collected from 25 sampling points in the basin. Also some important ecological indicators including potential ecological risk index (PERI), contamination factor (CF), pollution load index (PLI), biological risk index (BRI), and geo-accumulation index (Igeo) and some important statistical indicators including the Pearson correlation index (PCI), factor analysis (FA), and cluster analysis (CA) were applied to collected data. Levels of all the investigated PTEs in sediment of the basin show significant differences between the pre-lockdown and lockdown periods. The PTE contents have considerably decreased by 12.8%–45.4% during the lockdown period. Similarly, the results of applied sediment quality risk assessment indices showed significant improvement and the values have decreased by 22.4%–35.8%. In the lockdown period, reduction of industrial activities or limited production at many industrial facilities located in the basin reduced the amount of effluent, leading to significant improvement in sediment quality.

As economic development upstream in the Yangtze River basin has progressed in recent decades, the demand for sediment has rapidly increased and contributed to an expansion in sediment excavation that may affect the river's stability and navigation safety. In the current study, the distribution of gravel mining in the upstream reach of the Yangtze River was investigated using field measurements obtained from 2008 to 2017. An experimental investigation was then done to analyze the bed load behavior in a typical mined channel using a physical river model. Finally, a two-dimensional hydrodynamic-sediment transport numerical model was developed to predict the evolution of the mined channel. The results indicate that gravel mining was mainly distributed among the following nine river sections: Tongluoxia–Yibin, Erlong–Xianglutan, Naxi–Jinkou, Binpangqi–Hongyanqi, Chayuqi–Shenbeizui, Yangshipan–Shangbaisha, Dongxikou, Baisha–Wenzhongba, and Jiangjin– Shenzhongba. The gravel shoals near the riverbank have been destroyed, and the bed topography has been altered by up to 1.65 × 109 m3 over the past 10 years. A bed load velocity formula was proposed to describe bed load transport in the mined channel based on dimensional analysis. The recovery process of the excavation pits was slow in both the experiments and simulations, with only 0.12 and 1.39%, respectively, of the mined amounts of gravel being restored. Finally, the recovery rate of the mining pits gradually slowed as the sediment supply from upstream decreased, suggesting that the destroyed gravel shoals rarely returned to their original forms due to the combined operation of hydro-projects in upstream areas and limited sediment storage in the channel.

The Upper Indus Basin (UIB) supplies water resources for the downstream areas of the Indus Basin, and the associated climate changes have attracted considerable attention. Here, we project the aridity changes in the UIB during the 21st century relative to 1995-2014 based on 12 Coupled Model Intercomparison Project Phase 6 (CMIP6) models under the 3 Shared Socioeconomic Pathway (SSP) scenarios. The aridity index (AI), defined as the ratio of annual precipitation to potential evapotranspiration (PET), is applied to quantify the dry conditions. According to the median of the preferred models, the annual mean temperature is projected to increase continually in the UIB across the 21st century under SSP2-45 and SSP5-85, and it increases before the 2050s and then stabilizes afterwards under SSP1-26. Generally, PET will increase and AI will decrease (a drying trend) in the UIB during the 21st century. The regionally averaged AI over the UIB linearly decreases as global warming intensifies at a slope of 0.1 °C-1 under both SSP2-45 and SSP5-85. Remarkable increases in aridity occur in the northern and northwest parts of the UIB. Seasonally, the largest decrease in AI is seen in December-January-February, and the smallest occurs in June-�July-August. Furthermore, PET plays a key role in AI changes, excluding the southeast part of UIB, and the percent contribution of PET to AI changes tends to increase over time in the 21st century. Overall, AI and PET changes are primarily determined by thermodynamic factors in the UIB.

We described new sea surface CO2 observations in the south-western Indian Ocean obtained in January 2020 when a strong bloom event occurred south-east of Madagascar and extended eastward in the oligotrophic Indian Ocean subtropical domain. Compared to previous years (1991–2019) we observed very low fCO2 and dissolved inorganic carbon concentrations (CT) in austral summer 2020, indicative of a biologically driven process. In the bloom, the anomaly of fCO2 and CT reached respectively −33 µatm and −42 µmol kg−1, whereas no change is observed for alkalinity (AT). In January 2020 we estimated a local maximum of air–sea CO2 flux at 27∘ S of −6.9 mmol m−2 d−1 (ocean sink) and −4.3 mmol m−2 d−1 when averaging the flux in the band 26–30∘ S. In the domain 25–30∘ S, 50–60∘ E we estimated that the bloom led to a regional carbon uptake of about −1 TgC per month in January 2020, whereas this region was previously recognized as an ocean CO2 source or near equilibrium during this season. Using a neural network approach that reconstructs the monthly fCO2 fields, we estimated that when the bloom was at peak in December 2019 the CO2 sink reached −3.1 (±1.0) mmol m−2 d−1 in the band 25–30∘ S; i.e. the model captured the impact of the bloom. Integrated in the domain restricted to 25–30∘ S, 50–60∘ E, the region was a CO2 sink in December 2019 of −0.8 TgC per month compared to a CO2 source of +0.12 (±0.10) TgC per month in December when averaged over the period 1996–2018. Consequently in 2019 this region was a stronger CO2 annual sink of −8.8 TgC yr−1 compared to −7.0 (±0.5) TgC yr−1 averaged over 1996–2018. In austral summer 2019–2020, the bloom was likely controlled by a relatively deep mixed-layer depth during the preceding winter (July–September 2019) that would supply macro- and/or micro-nutrients such as iron to the surface layer to promote the bloom that started in November 2019 in two large rings in the Madagascar Basin. Based on measurements in January 2020, we observed relatively high N2 fixation rates (up to 18 nmol N L−1 d−1), suggesting that diazotrophs could play a role in the bloom in the nutrient-depleted waters. The bloom event in austral summer 2020, along with the new carbonate system observations, represents a benchmark case for complex biogeochemical model sensitivity studies (including the N2 fixation process and iron supplies) for a better understanding of the origin and termination of this still “mysterious” sporadic bloom and its impact on ocean carbon uptake in the future.

The purpose of this work is to estimate the Curie point depth, heat flow and geothermal gradient from spectral analysis of aeromagnetic data over the Bida and Baro areas, Bida Basin, north central Nigeria. The area covered is approximately 6050 km2 and bounded by latitudes 8° 30′ and 9° 30′ north and longitudes 6° 0′ and 6° 30′ east. The aeromagnetic maps were digitised at an equal interval, and the regional values were removed using polynomial fitting. The resulting residual data were subjected to the upward continuation technique to suppress the short-wavelength components of the residual magnetic anomalies. The upward continuation residual map was divided into eight overlapping blocks, and each block was spectrally analysed. The estimated Curie point depth ranges from 13.6 to 27.2 km, the geothermal gradient ranges from 21.3 to 42.6°C/km with an average value of 34.4°C/km and the corresponding heat flow ranges from 53.2 to 106.6 mW/m2. The average value of the geothermal gradient of 34.4°C/km indicates the possibility of hydrocarbon maturation in the area. Areas of geothermal anomalies with gradients greater than 40°C/km may be prospective for geothermal energy usage in Nigeria for generation of electricity.

The Dawenkou Basin is a Cenozoic terrestrial fault basin in Shandong Province, East China, containing abundant mineral resources, especially gypsum. Recently a borehole was drilled in this basin unearthing the upper and middle members of the Dawenkou Formation. From the upper member, well-preserved ostracodes were discovered, which are entirely non-marine taxa including species of Eucypris, Caspiolla, Candona and Candoniella. Based on the new material, a new species Candona dawenkouensis n. sp. was erected. The ostracode assemblage biostratigraphically indicates an age of middle Eocene to Oligocene of the upper member of the Dawenkou Formation and the strata bearing mineral resources (mainly gypsum) of the middle member of the Dawenkou Formation is likely early Eocene.

Southern Australia’s Cenozoic Eucla basin contains world-class strandline heavy mineral deposits. This study links detrital zircon U-Pb geochronology and heavy mineral compositions from four mineral sand prospects, and a suite of published deposits, to bounding Archean to Neoproterozoic crustal areas. A variable number of distinct sediment sources is recorded from each prospect’s detrital zircon age spectrum. This variability in zircon ages, quantified using a Shannon-Weaver test, serves as a metric of source region heterogeneity. Greater zircon age heterogeneity correlates with heavy mineral enrichment. Enhanced heavy mineral yields reflect retention of resistate over labile minerals—a function of greater sediment transport, reworking, and upgrading processes that parallel those that result in detrital zircon age polymodality. In this case study, greater reworking in intermediate storage sites and transport by longshore processes, eastward along the ~1,000 km spanned by the study sites, corresponds to the direction of progressive heavy mineral enrichment identified in zircon ages and mineral compositions. This approach is a proxy for the duration minerals have spent in the sedimentary system and provides an important perspective for understanding heavy mineral sands.

3D geocellular modeling is increasingly essential in the petroleum industry; it brings together all petroleum disciplines, and it is commonly used in simulation and production forecast. However, modeling slope and deep-water turbidite reservoirs using conventional modeling methods pose a significant challenge due to the structural complexity and thin-beds associated with these reservoirs. Through the innovative modeling technology of PaleoScan, the reservoirs in Sub member 3 of the third member of the Shahejie Formation are modeled to understand the structural framework. The resulting model is populated with petrophysical properties i.e., porosity and permeability to predict their lateral and vertical distribution within these sandstone reservoirs. The study suggests that the reservoir in the highstand system tract (HST) is characterized by the clinoforms configuration framework. The reservoir is highly faulted mainly in the northern and southeastern parts of the depression. The sedimentary layers are deposited across the slope and downlapping, thinning, and terminating toward to the west. The two isochore surface maps reveal sediment thickness variation and depositional trends within each individual depositional layer. The zones or areas that corresponds to low values on the thickness maps suggest minor uplifts associated with intensive faulting in the Eocene period. These topographical highs played a fundamental role in distributing the sediments delivered to the basin from distant sources. The maps reveal that sediments that filled the basin appear to come from different source points, primarily delivered from the north, southeast, and northeast of the basin with varying depositional trends. The modeled porosity and permeability indicate that the delta fed turbidite reservoirs are characterized by medium to high porosity values of 10–20% and low to medium permeability values of 30-410mD, respectively. The porosity values increase to the southeast and toward the basinwards (west) while permeability varies within the individual sedimentary layers. The distribution of porosity and permeability is not uniform vertically. This suggests the presence of mixed none-reservoir layers with locally and periodically deposited sandstone reservoirs within the stratigraphic during rapid delta progradation. The HST is characterized by six different delta progradation cycles; each phase produced locally deposited lacustrine turbidite sandstones in the basin, which are essential reservoirs in this Formation. The innovative PaleoScan interpretation technology has successfully created a high-resolution 3D reservoir model of this complex geology-such innovative technology is vital to similar complex geology globally.

Isolated pharyngeal teeth, pectoral, dorsal and suborbital fish spines were unearthed in a new outcrop located on the right bank of the Prut River, at Falciu, Romania. They document Late Miocene aquatic ecosystems of the Dacian basin. Seven taxa were identified and described, six of them belonging to the order Cypriniformes and one to Siluriformes. The Cobitidae is here firstly reported in the fossil record of Romania. All the fish teeth and skeletal remains are from representatives marking shallow water. The fossils were probably buried into sediments accumulated near the mouth of a rather fast-flowing river that drained into a brackish body of water, part of the Dacian basin. The composition of the fauna is similar to the coeval ones from the North (Ukraine and Republic of Moldova) and from the South (Turkey) of the Black Sea basin.

The Late Pliocene–Early Pleistocene is an important transitional period in the Cenozoic evolution of global climate and environment. Previously, we demonstrated the occurrence of distinct cycles in vegetation and climate in the Nihewan Basin, during 2.89–1.78 Ma. However, the specific cycles and their forcing mechanisms were not studied more in-depth. Here we present the results of wavelet and spectral analyses of pollen percentages (Picea, Pinus, xerophytic taxa and broadleaved trees), macro-charcoal concentration, clay % and sand %, and magnetic susceptibility of 340 samples from the NHA drill core in the Nihewan Basin, during 2.89–1.78 Ma. The results reveal dominant ~20-kyr and ~40-kyr cyclicities: the pollen percentages of Pinus and broadleaved trees, magnetic susceptibility, and clay %, indicating a warm and humid climate, are more significantly influenced by ~20-kyr; in contrast, the percentages of Picea and xerophytic taxa, macro-charcoal concentration, and sand %, associated with a cold and dry climate, are mainly influenced by ~40-kyr. The ~20-kyr and ~40-kyr cycles corresponding to the dominant cycles of the East Asian summer monsoon and winter monsoon, which are respectively driven by Earth orbital precession and tilt, indicating that vegetation and climate change in the Nihewan Basin during 2.89–1.78 Ma was forced by a combination of low- and high-latitude processes. Otherwise, most of the proxy indexes also show a pronounced ~100-kyr cycle, which may be a response to changes in Northern Hemisphere ice sheets, emphasizing the importance of high-latitude forcing of vegetation and climate change in the Nihewan Basin.