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The thickest section of Early Jurassic strata known from onshore Ireland (total Jurassic thickness 566 m) is reported from the Ballinlea-1 well (Rathlin Basin) situated on the north coast of Northern Ireland. A biostratigraphical and palaeoenvironmental assessment is presented for this section largely based on calcareous benthic microfossils (foraminifera and ostracods). The Early Jurassic Waterloo Mudstone Formation (Lias Group) of Northern Ireland has previously received little micropalaeontological attention, therefore this work provides an opportunity to enhance palaeogeographic and palaeoenvironmental understanding for the Early Jurassic of the province, and this paper illustrates the key microfossil taxa of this age from Ireland for the first time. The records, based on ditch-cuttings samples, demonstrate a stratigraphical range from Hettangian to Early Pliensbachian, consistent with other wells and boreholes in this basin. The assemblage compositions are comparable to those elsewhere in the European boreal Atlantic realm. Hettangian to earliest Sinemurian microfossil assemblages are generally of low diversity and are numerically dominated by metacopid ostracods with occasional influxes of foraminifera. Gradually, foraminiferal abundance (often dominated by species of the Lagenida) come to exceed those of the ostracods in the Early Sinemurian reaching their greatest diversity in the Late Sinemurian. The sediments are considered to represent an inner to mid-shelf environment throughout while the record thickness for this region indicates ongoing syn-sedimentary fault movement along the basin margins within this period.

The present climate simulation and future projection of the mixed layer depth (MLD) and subduction process in the subtropical Southeast Pacific are investigated based on the Geophysical Fluid Dynamics Laboratory Earth System Model (GFDL-ESM2M). The MLD deepens from May and reaches its maximum (>160 m) near (24°S, 104°W) in September in the historical simulation. The MLD spatial pattern in September is non-uniform in the present climate, which shows three characteristics: (1) the deep MLD extends from the southeastern Pacific to the West Pacific and leads to a “deep tongue” until 135°W; (2) The northern boundary of the MLD maximum is smoothly near 18°S, and MLD shallows sharply to the northeast; (3) There is a relatively shallow MLD zone inserted into the MLD maximum eastern boundary near (26°S, 80°W) as a weak “shallow tongue”. The MLD non-uniform spatial pattern generates three strong MLD fronts respectively in the three key regions, promoting the subduction rate. After global warming, the variability of MLD spatial patterns is remarkably diverse, rather than deepening consistently. In all the key regions, the MLD deepens in the south but shoals in the north, strengthing the MLD front. As a result, the subduction rate enhances in these areas. This MLD antisymmetric variability is mainly influenced by various factors, especially the potential-density horizontal advection non-uniform changes. Notice that the freshwater flux change helps to deepen the MLD uniformly in the whole basin, so it hardly works on the regional MLD variability. The study highlights that there are regional differences in the mechanisms of the MLD change, and the MLD front change caused by MLD non-uniform variability is the crucial factor in the subduction response to global warming.

In the present study, an attempt is made to delineate groundwater potential zones in Lower Rihand River Basin using remote sensing, GIS, and Analytical Hierarchical Process (AHP). Multiple data, viz. lithology, lineament density, geomorphology, slope, soil, rainfall, drainage density, relief, landuse/landcover were considered for delineating the groundwater potential zones. All nine thematic layers were prepared using remote sensing data on GIS platform. After that, weights were assigned to different layers and the features within them using a pairwise comparison matrix through the Analytical Hierarchical Process. The weights obtained were tested for their consistency using the consistency index and consistency ratio. A final weighted map was then obtained by multiplying each thematic layer’s weights with the weights of features within them and adding them. Based on this final weighted layer, the basin was categorized into very poor, poor, moderate, good, very good groundwater potential zones. The maximum area (49.22%) is under poor groundwater potential zone followed by moderate zone (26.17%), very poor (12.53%), good (11.77%), very good (0.31%). Results obtained have been validated using pre-monsoon and post-monsoon 10 years average water depth and seasonal fluctuation of various observation wells. Sensitivity analysis using map removal method is performed to assess the most influential parameters, geology, geomorphology, lineament density are the most influential. Overall results prove the efficacy of the use of geospatial technology in combination with AHP in the delineation of underground water potential zones.

Erosion of soil in the Lake Tana basin poses a critical economic and environmental crisis due to its impacts on agriculture productivity, food security and reservoir sedimentations. This study assesses soil erosion hazards by considering changes of land use and the climate. Simulation of land use change was conducted using CA_Markov chain model while climate was downscaledusing statistical techniques from CanESM2 model. The integration of the revised universal soil loss equation (RUSLE) with a geographic information system and remote sensing were used to estimate the soil loss. To quantify soil loss, six RUSLE model parameters were used: rainfall erosivity (R), soil erodibility (K), topography (LS), cover management (C), support and conservation practices (P). The average annual loss of soil by the 2080s in the basin is projected to be 7.7, 7.5 and 8.3 tons per hectare per year for changes land use, combined changes in land use and climate, and changes in climate under RCP8.5, respectively. Furthermore, by the end of this century, the soil loss in the basin tends to increase by 10.8%, 3.4% and 2.2% by considering changes in land use pattern, combined changes in land use and climate, and changes in climate, respectively, suggesting the aggravation of soil erosion in the basin. Accordingly, the effects of climate variability on annual average loss of soil are relatively higher than the combined effects of changing climate and land use. Consequently, the integration of RUSLE model with geospatial technology is recommended for an effective soil and water conservation measures.

Addressing the impact of dams and other water control structures on fish communities and aquatic ecosystems is a major concern for fisheries managers in the Laurentian Great Lakes. Although nature-like and technical fishways (i.e., vertical slot, pool and weir, Denil) and, when suitable, barrier removals have been implemented across the basin, these fish passage applications are vastly outnumbered by barriers to fish movement. Lowermost barriers are the first structure that blocks fish passage within a tributary; and, in the Laurentian Great Lakes, they present a unique situation where restricting access to upstream habitat is a major component of a half a century long strategy to control invasive sea lamprey Petromyzon marinus. Solutions for passage at lowermost barriers must therefore consider alternative management actions surrounding increased connectivity and invasive species control. These actions are underlined by the primary management objective of enhancing production/diversity of native and recreationally desirable fishes. This review surveys the current state of fish passage technologies deployed in the Laurentian Great Lakes and other fish passage solutions under development, providing a reference for resource managers making decisions about barriers and fish passage that are critical for invasive species control and fishery restoration.

Understanding the thermal conductivity of rocks is crucial for the development and utilization of geothermal reservoirs. In order to study the anisotropy of thermal conductivity of rocks, the thermal conductivities of granite, rhyolite, sandstone and mudstone in Songliao basin were tested, and the microstructure, mineral composition and content of the samples were analyzed by means of polarizing microscope and X-ray diffraction. The thermal conductivities of different rock types parallel to and perpendicular to the structural plane were obtained, and the anisotropic factors of the thermal conductivity of rocks in the songliao basin were calculated. The thermal conductivity of rocks with a high proportion of layered minerals is generally anisotropic. The thermal conductivity anisotropy of syenogranite, rhyolite and mudstone in Songliao basin is not obvious, and the variation range of anisotropic factors were 1.01–1.30, 1.02–1.10, and 0.87–1.11 respectively. The average anisotropy factor of thermal conductivity of granodiorite and sandstone is 1.12 and 0.89 respectively, indicating that these two kinds of rocks have anisotropy. Finally, according to the relationship between rock type, microstructure, mineral composition and anisotropy of thermal conductivity, the modified equation of anisotropy of rock thermal conductivity of Songliao basin was proposed.

To build an environment facility of a large-scale ocean basin, various detailed reviews are required, but it is difficult to find data that introduces the related research or construction processes on the environment facility. The current generator facility for offshore structure safety evaluation tests should be implemented by rotating the water of the basin. However, when the water in the large basin rotates, relatively large flow irregularities may occur and the uniformity may not be adequate. In this paper, design and review were conducted to satisfy the performance goals of the DOEB through computational numerical analysis on the shape of the waterway and the flow straightening devices to form the current in the large tank. Based on this, the head loss, which decreases the flow rate when the large tank water rotates through the water channel, was estimated and used as the pump capacity (impeller) design data. The impeller of the DOEB current generator was designed through computational numerical analysis (CFD) based on the lift surface theory from the axial-type impeller shape for satisfying the head loss of the waterway and maximum current velocity. In order to confirm the performance of the designed impeller system, the flow rate and flow velocity performance were checked through factory test operation. And, after installing DOEB, the current flow rate and velocity performance were reviewed compare with the original design target values.Finally, by measuring the current velocity of the test area in DOEB formed through the current generator, the spatial current distribution characteristics in the test area were analyzed. Through the analysis of the current distribution characteristics of the DOEB test area, it was confirmed that the realization of the maximum current velocity and the average flow velocity distribution, the main performance goals in the waterway design process, were satisfied.

The Indus River System is a major source of life in Pakistan. A vast array of Pakistan's agricultural and domestic consumption needs are critically dependent on the Indus River System. The Indus River contributes towards 25% of the country's gross domestic product, providing water for almost 90% of the food production in Pakistan. Linked to the water security issues, Pakistan is potentially at risk of facing a severe food shortage in the near future. The World Bank report of 2020–2021 estimates that the water shortage will increase to 32% by 2025, which will result in a food shortage of almost 70 million tons. Water shortage could also result in confrontation between the provinces as river sharing has always been a source of problem for Pakistan. According to recent estimates, siltation and climate change will reduce the water storage capacity by 2025 to almost 30%. As for the per capita water storage capacity in Pakistan, it is about 150 m3, which is quite meagre in comparison with that in other countries. Irrigated agriculture will soon be adversely affected due to the reduced surface water supplies and the consequent increase in groundwater abstraction. To make matters worse, over the past decades, a great deal of distrust has developed among the provinces of Pakistan regarding the water distribution issue, and the successive federal governments have failed to formulate a cohesive inter-provincial National Water Policy. Along with the shortages and increasing demand for water, administrative corruption also plagues the water sector and is quite common. The beneficiaries of this water reallocation system are not only the rural elite, for example the large and politically influential landlords, but also the small and medium capitalist farmers. If not properly addressed, these complications of decreasing water resources could result in serious political and economic hostility among the provinces. If it wants to harness its potential to increase storage capacity, Pakistan must improve its water-use efficiency and manage its groundwater and surface water resources in a sustainable way. Strengthening the institutions and removing mistrust among the provinces are the key elements for maintaining a sustainable irrigated agriculture in the Indus Basin. HIGHLIGHTS Indus River, a major source of life in Pakistan.; River sharing has always been a source of problem and confrontation between the provinces of Pakistan.; The paper highlights various problems in Pakistan's Indus Basin.; It also gives several recommendations for improving sustainability in Pakistan's Indus Basin.

The present study applied an ensemble of Bayesian SPARROW models in the eastern Georgian Bay drainage basin informed by multi-agency tributary water quality monitoring data collected in the area. Consistent with our current understanding of the role of wetlands in the Precambrian Shield, our analysis showed that they could be responsible for nearly 30% of the total phosphorus (TP) loading from forested areas and 23% of the delivered TP from the eastern Georgian Bay drainage basin. Agricultural areas contribute over 40% of the TP loading associated with anthropogenic activities, which was two times higher than the predicted nutrient losses per unit area in southern Georgian Bay. This finding raises concerns regarding the likelihood of elevated eutrophication risks from future expansion of agriculture in central and northern Ontario. Considering the uncertainty pertaining to their broader influence, cottage septic fields were estimated to be the second anthropogenic P source after agriculture, accounting for 9% of the delivered TP loading to the downstream outlets into Georgian Bay. Research on eutrophication of coastal embayments in Georgian Bay has historically focused on factors, such as basin morphometry, internal P loading, and dreissenid-mediated nearshore shunt. In this context, our SPARROW model offered an additional perspective by estimating that a significant fraction (≈90%) of the TP loading delivered to the Georgian Bay embayments could be originating from upstream sites, even though our predictions suggested that nearly half (49%) of P loading reaching the stream network deposits on the sediments of inland lakes in central Ontario.

Understanding the population structure of invasive sea lamprey (Petromyzon marinus) in the Great Lakes basin is essential for an effective control program. We review knowledge of lake connectivity, dispersal during the parasitic stage, and results from phenotypic, demographic, and genetic studies to evaluate how sea lamprey populations are structured. There is no evidence for contemporary movement between Lake Ontario and the Atlantic population, although it appears possible. Dispersal between Lake Ontario and the Finger Lakes is more likely, as is contemporary movement between Lakes Ontario and Erie via the Welland Canal, although neither has been directly observed. Downstream movement from Lake Erie to Lake Ontario via the Niagara River has been reported. Bidirectional movement between Lakes Erie and Huron has been observed, and movement of sea lamprey among the upper Great Lakes (especially between Lakes Huron and Michigan) is relatively common, although complete mixing likely does not occur. The maximum straight-line dispersal distance reported for a tagged sea lamprey was 628 km between the St. Marys River and western Lake Erie. Genetic population studies using a variety of molecular markers generally found weak but significant broad-scale population structure (e.g., between freshwater and anadromous populations, and among Lake Ontario, Lake Erie, and the upper Great Lakes), but finer-scale structure was rarely detected. Nevertheless, some within-basin structure is suggested by regional differences in phenotypic and demographic traits (e.g., sex ratio, body size). Further study will be important because management is most efficiently targeted when the geography of demographically independent populations is well-characterized.

Control of invasive sea lamprey in the Great Lakes with a selective pesticide (lampricide) that targeted larval sea lamprey began in the late 1950's and continues to be one of the main methods for control. Although the Great Lakes Fishery Commission, which was formed with the mandate of controlling sea lamprey, often expresses the success of the sea lamprey control program in terms of percent reduction from lake-wide pre-lampricide control adult sea lamprey abundances, there remains a large amount of uncertainty surrounding these estimates. In this study, we gathered historical data on adult sea lamprey captures from trapping efforts from the mid-1950's through the late 1970's to better understand pre-control abundance. We used this information to estimate lake-wide population abundances of adult sea lamprey using a weighted linear regression that includes environmental and lampricide treatment predictor variables. We varied trapping efficiency for early trapping data to evaluate the uncertainty in abundance estimates. Pre-control adult sea lamprey abundances in all lakes were much greater than current population sizes, but estimates were quite sensitive to trapping efficiency. In Lake Superior, declines in abundance aligned with increases in control efforts, but in other lakes, declines were occurring prior to the onset of lampricide application, perhaps because of a loss of prey. We suggest that previous estimates of pre-control adult sea lamprey abundance may have been underestimated unless trapping efficiency was greater than what is currently achieved in the basin.

Lake sturgeon, a species of conservation concern, can be affected by sea lamprey control activities in the Great Lakes basin. Specifically, age-0 lake sturgeon are sensitive to the pesticides used to kill larval stage sea lampreys; and, as tributary spawners, barriers that restrict access to habitat for adult sea lampreys can also restrict access to spawning lake sturgeon habitat. Conversely, lake sturgeon are also potentially prey for juvenile sea lampreys, so they benefit from control measures that reduce sea lamprey abundance. Over the past 20 years research has defined conditions under which treatments to control sea lampreys, such as high tributary alkalinity levels, are of highest risk for age-0 lake sturgeon mortality. Adult lake sturgeon are likely to survive a sea lamprey attack, and adult wounding rates vary through time and space across the Great Lakes basin and in Lake Champlain. Juvenile lake sturgeon are at higher risk of mortality from a sea lamprey attack, yet rarely display wounds. There are mitigation measures, including treating tributaries later in the year, capturing and holding age-0 lake sturgeon prior to treatment in high-risk tributaries, maximizing the time between treatments, and providing passage for spawning lake sturgeon above sea lamprey barriers that can minimize risks to lake sturgeon populations. As such, we believe that there remains room for both a robust sea lamprey control program moving forward in concert with lake sturgeon rehabilitation across the Great Lakes basin.

The late Paleozoic to Triassic was an important interval for the East Kunlun–Qaidam area, northern Tibet, as it witnessed prolonged subduction of the South Kunlun Ocean, a major branch of the Paleo-Tethys Ocean whose closure led to the formation of Pangea. However, the geologic history of this stage is poorly constrained due to the paucity of tectonothermal signatures preserved during a magmatic lull. This article presents a set of new provenance data incorporating stratigraphic correlation, sandstone petrology, and zircon U–Pb dating to depict changes in provenance that record multiple stages of topographic and tectonic transition in the East Kunlun–Qaidam area over time in response to the evolution of the South Kunlun Ocean. Devonian intra-arc rifting is recorded by bimodal volcanism and rapid alluvial-lacustrine sedimentation in the North Qaidam Ultra High/High Pressure Belt, whose sources include the Olongbuluke Terrane and southern North Qaidam Ultra High/High Pressure Belt. Southward transgression submerged the East Kunlun–Qaidam area during the Carboniferous prior to the rapid uplift of the Kunlun arc, which changed the provenance during the Early Permian. This shift in provenance for the western Olongbuluke Terrane and thick carbonate deposition throughout the North Qaidam Ultra High/High Pressure Belt in the late Early Carboniferous indicate that the North Qaidam Ultra High/High Pressure Belt should have been inundated, terminating an ~95 m.y. erosion history. The closure of the South Kunlun Ocean in the late Triassic generated a retroarc foreland along the Zongwulong Tectonic Belt, which is represented by the development of a deep-water, northward-tapering flysch deposystem that was supplied by the widely elevated Kunlun–Qaidam–Olongbuluke Terrane highland. This new scenario allows us to evaluate current models concerning the assembly of northern Tibet and the tectonic evolution of the Paleo-Tethys Ocean.

A large, incomplete fragment of arthropod cuticle with distinctive tuberculate ornamentation from the late Permian Kaloola Member, Baralaba Coal Measures of the Bowen Basin in central Queensland, i...

The study area is located in the eastern part of the Diyala Governorate close to the Iraqi-Iranian border. This study was set to investigate the hydrogeological calculations of northeast of Qazaniyah wells where the groundwater moves in directions of from the northeastern parts towards the southwestern par, that is, the same direction of the topography and the same direction of the tendency of the layers t. The study‘s region is characterized by visible geological layers or those that can be penetrated to a reasonable depth by wells which are sedimentary rocks deposited in continental or semi-continental conditions in the bays. From the study of the hydraulic properties of the two hydrogeological and exemplary systems, the values of transmissivity, permeability and storage coefficient are ranged between 1.94- 5.73 m2/day, 1.02- 3.92 m/day and1.40 x 10-5- 2.62 x 10-4, respectively. While the estimated value of transmissivities, which are obtained from specific capacity, ranged between 6.27- 8.62 m2/day. This variance in the values indicates the broad differences in the values Lithology of aquifers, which seems to be influenced by the strength and the number of fractures and joints.

Diachronic analysis of satellite images was used to assess the spatiotemporal dynamics of land use and land cover change in the coffee production basins of Cameroon, located in the forest agro-ecological zones (Moungo and Haut-Nyong) and the highland humid savannah (Noun). A survey of farmers was carried out to identify land use and changes in the area of coffee agroforests over time. While the period 1980 to 2001 was marked by an increase in the area of the forest/agroforest land-use unit, the period 2001 to 2019 shows significant regressions ranging from 14 to 22% of the total area of each basin. Significant changes in the land use units have repercussions on the areas dedicated to coffee growing, which have decreased significantly; today, the largest areas under cultivation are in Haut-Nyong (1.51±1.27 ha), the medium areas in Moungo (1.14±1.13 ha) and the smallest in Noun (0.67±0.72 ha). Coffee abandonment coupled with anthropogenic factors such as agriculture and housing expansion are mainly responsible for the degradation of coffee agroforests, with notable repercussions on land cover changes. The cocoa-coffee revival encouraged by sectoral Ministries in recent years seems to have encouraged cocoa production, since in agro-ecological regions; the increase in forest/agroforest area is mainly attributable to Theobroma cacao and Elaies guineensis. Key words: Spatio-temporal dynamics, land use/land cover, agroforestry system, coffee agroforest, coffee area, agro-ecological zone.

A new basin depth map for the Wellington Central Business District shows a maximum depth of 540 m near the Wellington Stadium. Our new basin geometry constraints are from a residual gravity anomaly...

The detailed sedimentary study of the deposit sequences of the ancient hominid sector (SahelanthropustchadensisalisToumai) of Toros-Menalla, presented here addresses new aspects of the sedimentary geology of the Chad Basin through an original field study of Moi-sediments: Pliocene of the northern basin of CHAD. This is an original contribution that sheds light on new knowledge of sedimentary series of fluvio-lacustrine and aeolian origin in the Djourab desert which are essential for understanding the paleoenvironments and paleoclimates of Chad, the Sahara and Africa. Aged from the Terminal Miocene to the present day, these deposits which constitute the last stages of the filling of this basin are exclusively of the continental type and concern in the broad sense the following four major sedimentary systems: Fluvial, deltaic, lacustrine and aeolian. From a lithological point of view, these sedimentary series are very heterogeneous and include sandstones, sands, clays and diatomites. Key words: Sedimentary deposit, Djourab, Toros-Menalla, Chad, fluvio-lacustrine, Aeolian.

We demonstrate how lithological and mechanical stratification of Ediacaran–Carboniferous sedimentary package governs strain partitioning in the Lublin Basin (LB) which was incorporated in the marginal portion of the Variscan fold-and-thrust belt. Based on the geometry of seismic reflectors, the pre-Permian–Mesozoic sedimentary sequence was subdivided into two structural complexes differing in structural style. The lower one reveals forelandward-vergent imbrication, while the upper one comprises fold train, second-order deformations, and multiple local detachments. Lithological composition of the upper structural complex controlled geometry, kinematics, and position of compressional deformations in stratigraphic profile. System of foreland-vergent thrusts which links lower and upper detachment developed due to efficiency of simple shear operating in heterogeneous clastic-carbonate-evaporitic strata of the Lower–Upper Devonian age. Internal homogeneity promoted the formation of conjugate sets of thrusts in Silurian shales and Upper Devonian limestones. Structural seismic interpretation combined with sequential restoration revealed localised thickening of Devonian strata and up to 5% difference in length of Devonian horizons. This mismatch is interpreted as a manifestation of distributed shortening, including layer-parallel shortening (LPS), which operated before or synchronously to the initiation of folding. The amount of distributed strain is comparable with numbers obtained in external parts of other fold-and-thrust belts. The outcomes derived from this study may act as a benchmark for studying variability in a structural style of multilayered sequences which were incorporated in the external portion of other fold-and-thrust belts.

In this manuscript, mathematical models for cropping water need (C.W.N) and the size of land for irrigation (S.L.I) were formulated. The solutions of the models for Crop water need for Soya beans and Rice, and the size of land for irrigation (S.L.I) of the two crops was obtained. We fill the gap by considering the size of the irrigation land which is not considered by the Food and Agriculture Organization (F.A.O). The computational Method of solutions is carried out to get effective results. The climatic data of the study area (Bida Basin) under which our research is based includes: Rainfall, Humidity, Sunshine hours, minimum and maximum temperature, evapotranspiration were secondary data collected from Nigeria Metrological Society (NIMET). We compared the results of CROPWAT 8.0 software developed by the Food and Agriculture Organization (F.A. O) and our computational method so that we can arrive at a new finding and better results. The results for the computational method with the size of Land for irrigation shows that there is an increase in crop water need for the crops than the results of CROPWAT 8.0 software developed by the Food and Agriculture Organization (F.A. O) in which the size for the land is not considered. We therefore, recommended that the integral calculus can be used to estimate the irregular shape of the size of the land if the land shape is not in rectangular form before solutions are given for accuracy and effective results.

Climate change has implications for water resources by increasing temperature, shifting precipitation patterns and altering the timing of snowfall and glacier melt, leading to shifts in the seasonality of river flows. Here, the Soil & Water Assessment Tool was run using downscaled precipitation and temperature projections from five global climate models (GCMs) and their multi-model mean to estimate the potential impact of climate change on water balance components in sub-basins of the Upper Indus Basin (UIB) under two emission (RCP4.5 and RCP8.5) and future (2020–2050 and 2070–2100) scenarios. Warming of above 6 °C relative to baseline (1974–2004) is projected for the UIB by the end of the century (2070–2100), but the spread of annual precipitation projections among GCMs is large (+16 to −28%), and even larger for seasonal precipitation (+91 to −48%). Compared to the baseline, an increase in summer precipitation (RCP8.5: +36.7%) and a decrease in winter precipitation were projected (RCP8.5: −16.9%), with an increase in average annual water yield from the nival–glacial regime and river flow peaking 1 month earlier. We conclude that predicted warming during winter and spring could substantially affect the seasonal river flows, with important implications for water supplies.

Aptian to Campanian sediments from the Western offshore to Central Orange Basin were studied by integrating molecular geochemistry, inorganic and isotopic studies to recognize their geochemical characteristics via the reconstruction of the Orange basin’s paleoweathering, paleosalinity, paleovegetation, paleoclimate, and tectonic records. Molecular analyses of both aliphatic and aromatic compounds reveal an input dominantly from a marine source. The source rocks accumulated in a reduced, anoxic, saline water column. Based on various biomarker proxies and vitrinite reflectance data, some samples are thermally mature to produce petroleum, while others are not. According to the V/Ni ratio, samples from the Orange Basin in South Africa are mainly anoxic, with only a few samples ranging from suboxic to anoxic. This is congruent with biomarker and isotope analyses that further indicate the presence of marine-derived source rocks with some terrestrial remains generating hydrocarbons. The investigated sediments are made up of intermediate igneous rocks that have undergone moderate chemical weathering. Geochemical figures on tectonic setting discriminant function diagrams revealed a continental rift of passive margin settings. As a result, the extrapolated crustal processes are directly analogous to the genesis and evolution of the Orange Basin, demonstrating Gondwana’s breaking up and the opening of the Atlantic Ocean Margin.

The Eurasian Otter Lutra lutra is an elusive, solitary animal that has one of the widest distributions of all palearctic mammals. Once widely distributed in Asia, the Eurasian Otter population is now vulnerable to urbanization, pollution, poaching, and dam construction. Eurasian Otter distribution in the Indian Himalayan rivers is little explored, and information from this high-altitude riverine ecosystem is sparse. This publication reports a rare photographic record of the Eurasian Otter which confirms its presence in the high-altitude temperate forest of the Upper Bhagirathi Basin, western Himalayan region. The otter was recorded during investigations of terrestrial and aquatic fauna in the Bhagirathi Basin (7,586 km2, 500–5,000 m) of Uttarakhand State, India from October 2015 to May 2019. Among aquatic fauna, Brown Trout were found to be abundant in high altitude river stretches, with a catch per unit effort of 1.02 kg h–1. Additionally, 26 families of freshwater macroinvertebrates underscored a rich diet available for the Brown Trout, which in turn is a potential food source for the otters. The riverine ecosystem is undergoing dramatic changes because of the increasing demand for hydropower plants in the Bhagirathi Basin. Although mitigation measures are currently in place for fish, the presence of otters further necessitates the need for targeted management for high-altitude Himalayan rivers. There is an imperative need for intensive otter surveys using methods such as camera traps in riparian habitats along the Bhagirathi River and its tributaries.

In a context of climate change and decreasing water resources, knowledge of recent flow evolution is essential. The present study focuses on the analysis of trends and spatio-temporal evolution of the Cavally River flow. In this study, 8 hydrometric stations, including 6 on the main river (Flampleu, Ity, Toulepleu, Tai, Fete and Tate) and two tributaries (N'Ce and Niebe) of the Cavally River were selected based on the availability and quality of long-term data. Annual and monthly data from these stations cover the period from 1980 to 2016. Statistical methods and the Hanning low-pass filter are used to highlight the evolution of the annual mean discharge and the spatial distribution of the different hydrometric seasons over the period 1980-2016. Hanning low-pass filter, Mann-Kendall tests (Classic, Modified and Seasonal) and SNHT were applied to detect and analyze the significance of change over time. The results of the statistical tests and Hanning's low-pass filter show the seasonal and annual change in flows. Stations in the northern part of the basin generally had a long dry period from 1980 to 2010 and a wet period from 2011 to 2016 and those in the central part had a wet period from 1980 to 2005 and dry period from 2006 to 2016. Stations in the central part have alternating normal periods. The significant increase in runoff during the dry season and some months of the rainy season was the main reason for the increase in annual runoff due to the considerable contributions of these seasons to the total runoff volume in the Cavally basin. Based on the results of the SNHT test for detecting abrupt changes in the series, about 62% of the series show a significant break, of which 60% are ascending at the 5% to 1% significance level. All observed breaks are generally located between 2000 and 2013.

Late to post-Caledonian, Devonian extension remains unresolved in the SW Barents Sea, despite considerable knowledge from onshore Norway, East Greenland and Svalbard. We analyse intrabasement seismic facies in high-resolution 3D and reprocessed 2D data to investigate evidence for Caledonian deformation and post-Caledonian detachment faulting in the central SW Barents Sea. These results are compared to published potential field models and analogue field studies from onshore Svalbard and Bjørnøya, substantiating that structures inherited from post-orogenic extension influenced the Late Paleozoic and Mesozoic basin evolution. The Late Paleozoic Fingerdjupet Subbasin is underlain by a NNE-striking, ESE-dipping extensional detachment fault that records a minimum eastwards displacement of 22 km. The detachment fault and associated shear zone(s) separate post-orogenic metamorphic core complexes from the syn-tectonic deposits of a presumed Devonian supradetachment basin. Spatial variability in isostatically induced doming likely governed Devonian basin configurations. Pronounced footwall corrugations and faults splaying from the detachment indicate eastward extensional transport. This ultimately led to two interacting but subsequent, east-stepping detachments. Local reactivation of the detachment systems controlled the extent of Carboniferous carbonate and evaporite basins in the Bjarmeland Platform area. Further, the Mesozoic Terningen Fault Complex and Randi Fault Set testify to how the inherited Devonian structural template continued to control spatial localisation and extent of rift structures during subsequent periods of extensional faulting in the Fingerdjupet Subbasin.

Nitrogen (N) legacies have built up in anthropogenic landscapes over decades of agricultural intensification, and these legacies lead to time lags in water quality change measurable even beyond the moment of application of N. It is important to understand these legacies to quantify the relationship between N inputs and N concentrations in streams and implement best management practices for water quality improvement; however, little is known about the magnitude of legacies in various landscape elements like soils and groundwater. Here, we have used the ELEMeNT (Exploration of Long-tErM Nutrient Trajectories) model to explore the buildup and depletion of N legacies over a 216-year period, across the Mondego River Basin, a 6645-km2 watershed in Portugal, where human interventions have considerably changed the characteristics of the basin to prevent floods and improve farming conditions in recent decades. The results show that the increase in the amount of inorganic fertilizer applied was the main driver for the anthropogenic N loads in the watershed from 1950 until the beginning of the 1990s. The N inputs have been decreasing since then, but N loads in the river did not document any decrease till the 1990s; after which there was a decline. This time lag between the N inputs to the watershed and the N loads in the river (about two decades) is a function of accumulation of N legacy.

Precipitation plays a critical role in hydrometeorological studies. A predictive analysis of gridded rainfall datasets may provide a cost-effective alternative to conventional rain gauge observations. Here, our objective is to evaluate the performance of satellite and reanalysis precipitation products in the hydrological modeling of a mesoscale watershed. The research also examines the accuracy of hydrological simulations in a sizeable flood-prone watershed in the absence of observed data associated with the myriad water retaining structures present in the catchment. We use three precipitation products, namely Tropical Rainfall Measurement Missions (TRMM) 3B42 Version 7, Climate Forecast System Reanalysis (CFSR), and daily precipitation data recorded at multiple rain gauges in the upper Huai River Basin to simulate streamflow. The Soil & Water Assessment Tool (SWAT) is utilized for runoff modeling, while SWAT-CUP is used to perform sensitivity analysis and to calibrate and validate the simulation results. Nash–Sutcliffe efficiency, percent bias, and Kling-Gupta efficiency (KGE) are employed to evaluate modeling efficiency for three precipitation datasets on different temporal scales. The results indicate that TRMM and CFSR datasets provide satisfactory results on both daily and monthly scales. Specifically, the SWAT model performs better at monthly simulations than daily simulations for all precipitation datasets used. HIGHLIGHTS Examining the applicability of TRMM and CFSR daily precipitation products in simulating runoff from a large watershed.; Calibrating a hydrological model in the absence of data associated with extensive anthropogenic activities for flood prevention and diversion.; Performing streamflow simulations using a SWAT model and parameter calibration and sensitivity analysis using a SUFI-2 algorithm.

ABSTRACT A bonebed of multiple skeletons of the Triassic horned reptile Shringasaurus indicus was discovered in the upper Denwa Formation, Satpura Gondwana Basin, India. The monotaxic bonebed contains multiple individuals of different ontogenic stages indicating herding behavior by Shringasaurus indicus. The herd was a mixed-sex herd. The adult and sub-adult bones in the bonebed exceed the number of juvenile bones. The distribution of the bones was slightly patchy, bones of different individuals were admixed, and several bones were piled up implying mass mortality. The bonebed occurs in a fine-grained mudrock that is hydraulically incompatible with long-distance transport and concentration by currents. Sedimentary facies analysis indicates that the bonebed accumulated and was buried in a crevasse splay deposit between two ENE-WSW trending channel-fill complexes. The northern channel-fill complex was formed by unidirectional flow with lateral channel migration towards the south and with minor contemporaneous tectonic subsidence. Repeated breaching of the levee by this channel flow led to the incremental development of the crevasse splay deposit. The herd of Shringasaurus indicus, which lived near to the perennial channel, was drowned en masse and the carcasses were trapped within the muddy sediments of the crevasse splay deposit. Apart from a partially articulated skeleton, the rest of the bones were disarticulated but remained associated. The bones show little evidence of post-mortem modifications. With a continuous supply of the sediments through the spillover channels, the bones were buried before complete disarticulation and dispersal had taken place.

The island nature of the Aztec capital, Tenochtitlan, is an under-studied aspect in our understanding of this unique urban space, located in the Mexican highlands of Mesoamerica. The island location induces cross-links from aquatic and terrestrial paths to create connectivity and continuity within the lacustrine cultural landscape of the Basin of Mexico during the Postclassic period (a.d. 900–1521). Although Cortés described this city as the “Venice of the New World,” no specific and systematic investigation of facilities related to water transport has been carried out. In this article, I fill this gap through a study of navigation routes which were conceived to facilitate the continuous movement of people and goods through the numerous canals crisscrossing the Aztec capital, and which are identifiable by means of anthropic markers that respond to functional needs. Transition zones (piers, quays, shoreline areas), coordination zones (ports), and activity zones (customs facilities, warehouses, bridges, sacred sites) are all related to the practice of water transport and intimately related to terrestrial roads. I identify and locate these areas using a multidisciplinary methodology based on archaeological data, ethnohistorical testimonies, and pictographic and iconographic documents.

A comprehensive updated inventory of glacial lakes in the Indus River basin (up to the Indian administrative boundary) has been carried out using 157 high-resolution Indian Remote Sensing satellite images, mostly covering mountainous region of the Western Himalayas and Karakoram Ranges. Glacial lakes are classified in ten different types depending upon dam type, process of lake formation, topographic feature, and geographical position. Distribution of glacial lakes has been studied in terms of area, type, area versus type, elevation, elevation versus type, and area versus elevation at basin and subbasin levels, along with Indian administrative and transboundary region level. A total of 5335 glacial lakes ≥ 0.25 ± 0.06 ha has been inventoried in the Indus River basin covering a total water spread area of 17395.03 ± 1013.28 ha. About 4633 (86.84%) glacial lakes are with

In the study, the content and speciation of Mn, Pb, Cd, Zn, Cr, Ni, Co, Cu, and Fe in the snow cover at the mouth of the Onega river (White Sea basin) at the end of the winter periods in 2018, 2019 and 2020 were determined. Winter 2019 year was the snowiest, as the maximum values of the snow cover depth and water equivalent were almost two times higher than in all other years. The total content of suspended matter in the snow cover was 0.2–5.5 μg/L. Increased concentrations of suspended solids were identified near highways. Mn, Cr and Ni were present in the snow cover mainly in their dissolved form, while Fe, Pb and Co were mostly contained as solids. The algological composition of the snow cover was also studied.

Detailed investigation on hydrogeochemistry of hard rock terrains is important to identify the major geochemical processes and the source of ionic constituents in groundwater. The present study is carried out to understand the hydrogeochemistry of groundwater resources and the major hydrogeochemical processes, controlling the concentration of major ions in groundwater in the Kallada River Basin (KRB), South India. About 166 groundwater samples were collected from KRB during pre- and post-monsoon of 2016 for hydrogeochemical analysis. Most of the groundwater samples in KRB were within permissible limits of drinking water quality. The dominant groundwater types during pre-monsoon were Ca2+-Mg2+-Cl− which was changed to Na+-Cl− during post-monsoon. This is supported by the inverse relationship of depth of wells and change in EC during pre- and post-monsoon periods. Rock-water interaction processes such as reverse ion exchange and silicate weathering are major geochemical processes responsible for the hydrogeochemical signatures of KRB. The shallower wells (< 10 m) show strongest relation with the water types Na+-HCO3− and Ca2+-Mg2+-Cl− which have been changed to Na+-Cl− and Ca2+-Mg2+-HCO3− during post-monsoon. However, in deeper wells, Na+-Cl− is the dominant type of water during both seasons. The hierarchical cluster analysis displays different hydrogeochemical associations representing diverse physicochemical parameters both spatially and temporally. This study could shed light on diverse hydrogeochemical processes which are responsible for the hydrogeochemistry in KRB. Major hydrogeochemical processes in the Kallada River Basi

Despite being poorly known from limited skeletal remains as teeth and a few postcranial material, spinosaurid remains have been reported from two different Lower Cretaceous localities in Brazil, wi...

Thus far, reanalysis-based meteorological products have drawn little attention to the influence of meteorological elements of products on hydrological modeling. This study aims to evaluate the hydrological application potential of the precipitation, temperature, and solar radiation of the China Meteorological Assimilation Driving Datasets for the Soil and Water Assessment Tool (SWAT) model (CMADS) and Climate Forecast System Reanalysis (CFSR) in an alpine basin. The precipitation, temperature, and solar radiation of the gauge-observed meteorological dataset (GD), CFSR, and CMADS were cross-combined, and 20 scenarios were constructed to drive the SWAT model. From the comprehensive comparisons of all scenarios, we drew the following conclusions: (1) among the three meteorological elements, precipitation has the greatest impact on the simulation results, and using GD precipitation from sparse stations yielded better performance than CMADS and CFSR; (2) although the SWAT modeling driven by CMADS and CFSR performed poorly, with CMADS underestimation and CFSR overestimation, the temperature and solar radiation of CMADS and CFSR can be an alternative data source for streamflow simulation; (3) models using GD precipitation, CFSR temperature, and CFSR solar radiation as input yielded the best performance in streamflow simulation, suggesting that these data sources can be applied to this data-scarce alpine region.

Sedimentary rocks of the Paradox Basin of the Colorado Plateau (southwestern USA) record widespread manifestations of paleo–fluid flow and fluid-rock reactions including Cu, U-V, and Fe-Mn mineral deposits, Si and Ca metasomatism, hydrocarbon accumulations, and bleached sandstones. Many of these are spatially associated with faults. Here we show evidence for a widespread phase of fault-related fluid migration and mineralization at 41–48 Ma in the Paradox Basin. We measured K-Ar dates of multiple size fractions of clay-rich fault gouge, yielding statistically overlapping dates of authigenic (1Md) illite for the Salt Valley (47.0 ± 3.0 Ma), Kane Springs (47.7 ± 3.8 Ma), Cliffdweller (43.4 ± 4.6 Ma), Courthouse (41.9 ± 2.3 Ma), Lisbon Valley (45.3 ± 0.9 Ma), and GTO (48.1 ± 2.6 Ma) faults. The latter two have an illite Rb-Sr isochron age of 50.9 ± 3.5 Ma, and fault-adjacent bornite has a Re-Os isochron age of 47.5 ± 1.5 Ma. Authigenic illite from a paleo–oil reservoir near the Courthouse fault formed from the interaction of reduced fluids with oxidized red-bed sandstones at 41.1 ± 2.5 Ma. The Moab and Keystone faults have older authigenic illite ages of 59.1 ± 5.7 Ma and 65.2 ± 1.0 Ma, respectively. Our results show a close temporal relationship between fault gouge formation, red-bed bleaching, and Cu mineralization during an enigmatic time interval, raising questions about drivers of Eocene fluid flow.