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Temporal trends of hydro-climatic variables and their relevance in water resource management 认领
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作者 Karim Solaimani Mahmoud Habaibnejad Abdollah Pirnia 《国际泥沙研究:英文版》 SCIE 2021年第1期63-75,共13页
Identification of temporal changes in hydrological regimes of river basins is an important topic in contemporary hydrology because of the potential impacts of climate change on river flow regimes.For this purpose,long... Identification of temporal changes in hydrological regimes of river basins is an important topic in contemporary hydrology because of the potential impacts of climate change on river flow regimes.For this purpose,long-term historical records of rainfall(P),runoff(Q)and other climatic factors were used to investigate hydrological variability and trends in the Tajan River Basin over the period 1969e1998.Actual evaporation(E),rainfall variability index(d),evaporation ratio(CE)and runoff ratio(CQ)were estimated from the available hydroclimatological records.Mann-Kendall trend analysis and nonparametric Sen's slope estimates were performed on the respective time series variables to detect monotonic trend direction and magnitude of change over time.Rainfall variability index showed that 1973 was the wettest year(δ=+2.039)while 1985 was the driest(δ=-1.584).Also,decades 69e78 and 89e98 were recognized as the wettest and driest decades respectively.The gradient of variation of climatological parameters showed that during the study period,all three parameters of rainfall,evaporation and runoff have decreased and the variations of rainfall and evaporation were significant at the 95%level.Investigation of hydrological changes due of dam construction(1999)showed that the amount and annual distribution of discharge were completely different pre and post-dam construction.Discharge decreased in high water months and increased in low water months to meet water supply demands,especially for agriculture.The relationship between temperature and rainfall trends is compared for three stations in Mazandaran Province(Gorgan,Babolsar and Ramsar)from 1956 to 2003 and nine other stations with different statistical periods of 19e36 years,relating trends to northern hemisphere and global trends.Decreases in temperature were accompanied by decreases in rainfall,and vice versa.These trends were not observed in northern hemisphere and world scales,where temperature increases are accompanied by decreases in rainfall.These variations of hydroc 展开更多
关键词 Climate change Human activity Hydroclimatological Trend analysis Mazandaran Tajan basin
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文章速递A large epeiric methanogenic Bambuí sea in the core of Gondwana supercontinent? 认领
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作者 Sergio Caetano-Filho Pierre Sansjofre +7 位作者 Magali Ader Gustavo M.Paula-Santos Cristian Guacaneme Marly Babinski Carolina Bedoya-Rueda Matheus Kuchenbecker Humberto L.S.Reis Ricardo I.F.Trindade 《地学前缘:英文版》 SCIE CAS CSCD 2021年第1期203-218,共16页
Carbon isotope compositions of both sedimentary carbonate and organic matter can be used as key proxies of the global carbon cycle and of its evolution through time,as long as they are acquired from waters where the d... Carbon isotope compositions of both sedimentary carbonate and organic matter can be used as key proxies of the global carbon cycle and of its evolution through time,as long as they are acquired from waters where the dissolved inorganic carbon(DIC)is in isotope equilibrium with the atmospheric CO2.However,in shallow water platforms and epeiric settings,the influence of local to regional parameters on carbon cycling may lead to DIG isotope variations unrelated to the global carbon cycle.This may be especially true for the terminal Neoproterozoic,when Gondwana assembly isolated waters masses from the global ocean,and extreme positive and negative carbon isotope excursions are recorded,potentially decoupled from global signals.To improve our understanding on the type of information recorded by these excursions,we investigate the pairedδ^13Ccarb andδ^13Corg evolution for an increasingly restricted late Ediacaran-Cambrian foreland system in the West Gondwana interior:the basal Bambui Group.This succession represents a 1~(st)-order sedimentary sequence and records two majorδ^13Ccarb excursions in its two lowermost lower-rank sequences.The basal cap carbonate interval at the base of the first sequence,deposited when the basin was connected to the ocean,hosts antithetical negative and positive excursions forδ^13Ccarb andδ^13Corg,respectively,resulting inΔ^13C values lower than 25‰.From the top of the basal sequence upwards,an extremely positiveδ^13Ccarb excursion is coupled toδ^13Corg,reaching values of+14‰and-14‰,respectively.This positive excursion represents a remarkable basin-wide carbon isotope feature of the Bambui Group that occurs with only minor changes inΔ^13C values,suggesting change in the DIC isotope composition.We argue that this regional isotopic excursion is related to a disconnection between the intrabasinal and the global carbon cycles.This extreme carbon isotope excursion may have been a product of a disequilibria between the basin DIC and atmospheric CO2 induced by an active methanogenesis,favored by the basin restriction.The drawdown of sulfate reservoir by microbial sulfate reduction in a poorly ventilated and dominantly anoxic basin would have triggered methanogenesis and ultimately methane escape to the atmosphere,resulting in a^13C-enriched DIC influenced by methanogenic CO2.Isolated basins in the interior of the Gondwana supercontinent may have represented a significant source of methane inputs to the atmosphere,potentially affecting both the global carbon cycle and the climate. 展开更多
关键词 Methanogenesis Ediacaran Cambrian Carbon isotopes Sao Francisco Basin Bambui Group
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文章速递Estimating daily actual evapotranspiration of a rice–wheat rotation system in typical farmland in the Huai River Basin using a two-step model and two one-step models 认领
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作者 LI Meng CHU Rong-hao +2 位作者 Abu Reza Md.Towfiqul ISLAM JIANG Yue-lin SHEN Shuang-he 《农业科学学报:英文版》 SCIE CAS CSCD 2021年第1期274-288,共15页
The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing season... The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing seasons of winter wheat and rice crops cultivated in a farmland ecosystem(Shouxian County) located in the Huai River Basin(HRB), China. The first model is a two-step model(PM-Kc);the other two are one-step models(e.g., Rana-Katerji(R-K) and advection-aridity(AA)). The results showed that the energy closure degrees of eddy covariance(EC) data during winter wheat and rice-growing seasons were reasonable in the HRB, with values ranging from 0.84 to 0.91 and R2 of approximately 0.80. Daily ET of winter wheat showed a slow decreasing trend followed by a rapid increase, while that of rice presented a decreasing trend after an increase. After calibrating the crop coefficient(Kc), the PM–Kc model performed better than the model using the Kc recommended by the Food and Agricultural Organization(FAO). The calibrated key parameters of the R-K model and AA model showed better universality. After calibration, the simulation performance of the PM-Kc model was satisfactory. Both the R-K model and AA model underestimated the daily ET of winter wheat and rice. Compared with that of the R-K model, the simulation result of the AA model was better, especially in the simulation of daily ET of rice. Overall, this research highlighted the consistency of the PM-Kc model to estimate the water demand for rice and wheat crops in the HRB and in similar climatic regions in the world. 展开更多
关键词 daily evapotranspiration crop coefficient crop water demand rice–wheat rotation system Huai River Basin
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Anatomy of Eastern Niger Rift Basin with Specific References of Its Petroleum Systems 认领
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作者 Kabir Shola Ahmed Keyu Liu +4 位作者 Mioumnde Arthur Paterne Kouassi Louis Kra Abigail Adu-Asante Kuttin Kue Petou Rokis Malquaire Kusi Micheline Michelle-Alexia Ngum 《地球科学国际期刊(英文)》 2020年第5期305-324,共20页
An attempt is made in this paper to present the dynamics of the Eastern Niger Rift Basin (ENRB) with references to the key features and processes of petroleum systems based on published information. The Eastern Niger ... An attempt is made in this paper to present the dynamics of the Eastern Niger Rift Basin (ENRB) with references to the key features and processes of petroleum systems based on published information. The Eastern Niger Basin is a superimposed rift basin with sedimentary structures emplaced during two rifts episodes. The Cretaceous episode is characterized by large, tilted normally faulted blocks trending NW-SE, that were reactivated in the Paleogene, while the Paleogene episode is characterized by normal faulted blocks that trend NNW-SSE. The rifting resulted in different basin structures with the north section dominated by asymmetric half-grabens while the south section is dominated by full-grabens. Three source rocks each belonging to three different play fairways exist: 1) The Paleogene Sokor-1 Member source belongs to second cycle syn-rift play associated with fluvial/deltaic facies;2) Cretaceous Yogou and Donga sources from first cycle post-rift play associated with alluvial/fluvial/deltaic and marine clastic and carbonate facies;and 3) Cretaceous Yogou source from first cycle transitional play associated with mudstone and shale of transitional facies. The ENRB comprises two source-reservoir-seal assemblages: a lower assemblage of Upper Cretaceous and an Upper assemblage of the Paleogene. Except for the Yogou source which possesses a self-contained petroleum system, the rest of the source rocks release their oils into the Paleogene Sokor-1 Member reservoir sealed regionally by the Oligocene Sokor-2 Member. The Paleogene assemblage is charged from the Upper Cretaceous Yogou Formation through fractures emplaced during the rifting episodes. 展开更多
关键词 RIFT Petroleum Source Rock Oil MIGRATION BASIN Evolution EASTERN NIGER RIFT BASIN
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Revised Stratigraphy and Mineral Resources of Balochistan Basin, Pakistan: An Update 认领
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作者 Muhammad Sadiq Malkani 《地质学期刊(英文)》 2020年第7期784-828,共45页
The Balochistan basin is located on the south western part of Balochistan Province and also Pakistan. Balochistan super basin is subdivided into northern Balochistan (Pishin basin or Kakar Kohorasan basin represented ... The Balochistan basin is located on the south western part of Balochistan Province and also Pakistan. Balochistan super basin is subdivided into northern Balochistan (Pishin basin or Kakar Kohorasan basin represented as back arc basin), central Balochistan (Chagai-Raskoh-Wazhdad Magmatic arc and Hamuns-Inter arc basin) and southern Balochistan (Makran Siahan basin) basins. Balochistan basin consists of Cretaceous to recent sediments, diverse igneous rocks and low grade metamorphics. Balochistan basin is a leading basin which consists of very significant mineral deposits especially copper and gold deposits. These mineral resources need to be developed for the development of areas, province and Pakistan. During previous half century a lot of geological work has been done in Balochistan basin. Here the revised stratigraphic set up and its mineral resources with an update are being presented. 展开更多
关键词 Revised Stratigraphy Mineral Resources Kakar-Khorasan Chagai-Raskoh-Wazhdad Magmatic Arcs Makran-Siahan Basin Balochistan Basin Pakistan
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文章速递Alleviating Water Scarcity in the Central Rift Valley Lakes through an Inter-Basin Water Transfer, Ethiopia 认领
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作者 Belete Berhanu Ethiopia Bisrat 《自然资源(英文)》 2020年第12期554-568,共15页
Demand for fresh water, as one of the major natural resources, is increasing rapidly with increasing development and environmental degradation. The continued abstraction of water from Lake Ziway and its main feeder ri... Demand for fresh water, as one of the major natural resources, is increasing rapidly with increasing development and environmental degradation. The continued abstraction of water from Lake Ziway and its main feeder rivers Meki and Katar for irrigation indicates that the water demand may soon exceed the supply. To illustrate disparities in spatial distribution of water resources, the Upper Awash sub-basin, which shares a water-divide with the CRVL sub-basin, has large flow volumes particularly in the rainy season and suffers with seasonal flooding. The rationale behind regaining the water in CRVL relies on this non-uniform spatial distribution of fresh water, calling for a balance between water surplus and deficit regions. For this reason, Inter Basin Water Transfer (IBWT) is suggested as a viable option to augment utilizable water resources of the Upper Awash sub-basin to reduce the significant pressure on the water supply of the rapidly developing urban and irrigation areas in the CRVL sub-basin. A water evaluation and planning (WEAP) model was used to quantify the amount of surplus water in the donor basin, when examining the hydrological dynamics of the basins. Furthermore, optimal flow diversion scenarios were generated by maintaining two baseline scenario constraints. The estimated surplus water in the rainy season is expected to contribute 18 million cubic meters (mcm), 88 mcm and 192 mcm in months June, July and August respectively under average conditions. The optimal amount of diverted water could potentially stabilize the environmental degradation of Lake Ziway and Lake Abijata by compensating for development-driven abstraction and surface water evaporation respectively. 展开更多
关键词 Inter Basin Water Transfer WEAP Lake Ziway Upper Awash Sub-Basin CRVL
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The hydrosocial cycle in rapidly urbanizing watersheds 认领
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作者 Melinda LAITURI 《地球科学前沿:英文版》 SCIE CAS CSCD 2020年第2期256-267,共12页
Water is the essential resource of the 21st century where innovative water management strategies are needed to improve water security.This paper examines three case studies that exemplify the global water crisis,situa... Water is the essential resource of the 21st century where innovative water management strategies are needed to improve water security.This paper examines three case studies that exemplify the global water crisis,situated in rapidly urbanizing watersheds:Nairobi River Basin,Kenya;Citarum River Basin,Indonesia;and Addis Ababa River Basin,Ethiopia.Each of these watersheds are implementing large-scale water management strategies inclusive of local communities and regional governments to address water quality and waste management issues.The hydrosocial cycle(Linton,2010)provides a framework to investigate the social,technical and physical aspects of water flows.Using the hydrosocial cycle as an organizing framework,these watersheds are examined to highlight how water security underpins water justice.The issues of gender and inequity are often overlooked in larger policy,development,and infrastructure discussions where technical requirements,restoration management,and engineering solutions obscure power inequities.Projects are compared to assess the implementation of the hydrosocial cycle through a discussion of social power and structure,technology and infrastructure,and the materiality of water in each location.This comparison reveals a dependence on large-scale technical projects with limited community engagement,and a need for science-based river restoration management.Recommendations are provided to improve and address holistic water management. 展开更多
关键词 hydrosocial cycle urban watersheds water security Citarum River Basin Addis Ababa Basin Nairobi River Basin
我国流域水管理法律体制的演变与发展 认领
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作者 何艳梅 《水利经济》 2020年第6期25-30,36,82,共8页
依据水事四法、流域立法、国家政策和改革实践,对我国流域水管理法律体制的演变和发展进行了历史分析和定性评价,指出我国流域水管理从最初的区域管理体制,演变为流域管理与区域管理相结合的体制,目前仍然处于变革之中。近年来的流域管... 依据水事四法、流域立法、国家政策和改革实践,对我国流域水管理法律体制的演变和发展进行了历史分析和定性评价,指出我国流域水管理从最初的区域管理体制,演变为流域管理与区域管理相结合的体制,目前仍然处于变革之中。近年来的流域管理机构改革强化了流域管理,河长制的实施强化了区域管理与科层协调,环境监管体制改革要求在生态环保部门建立流域管理机构,国务院和地方政府机构改革则优化了多部门区域管理;这些先后实施的政策和措施之间缺乏统筹,使流域管理与区域管理相结合的体制出现了一定程度的割裂,需要通过进一步的改革予以健全和完善。 展开更多
关键词 流域 水管理体制 流域管理 区域管理 流域管理机构
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Structural Model of Kendeng Basin: A New Concept of Oil and Gas Exploration 认领
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作者 Ardian Novianto Sutanto +4 位作者 Suharsono Carolus Prasetyadi Tavip Setiawan 《长江油气:英文版》 2020年第4期200-215,共16页
Kendeng Basin stretches in an E-W direction from the Quaternary Merapi-Ungaran Volcano range in the West to the Madura Strait East of Jawa Timur Province, Indonesia. With Quaternary volcanic deposits covering this bas... Kendeng Basin stretches in an E-W direction from the Quaternary Merapi-Ungaran Volcano range in the West to the Madura Strait East of Jawa Timur Province, Indonesia. With Quaternary volcanic deposits covering this basin, its subsurface configuration has not been accurately identified. Several scholars suggest that its configuration forms an asymmetrical basin deepening to the south as a result of volcanic deposits and extending E-W direction. This paper answers what configuration Kendeng Basin has, including whether it consists of a simple asymmetrical shape as previous studies have interpreted or other patterns due to tectonic processes that took place during its formation. The research employed Gravity and Magnetic method, and the results were processed by spectral and gradient analyses. Both analyses revealed that Kendeng Basin formed Horst-Graben structures extending in an E-W direction based on a response to compression and strain forces during its formation. A structure with an E-W direction controls the shape of the Horst-Graben and is transected by a structural pattern extending in a NE-SW direction or known as the Meratus pattern. These findings provide an alternative to the concept of oil and gas exploration, which, until today, is merely known from the emergence of oil seepages in Kendeng Basin. 展开更多
关键词 Kendeng Basin STRUCTURE Gravity-Magnetic
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Porosity distribution in cyclic dolomites of the Lower Qiulitag Group(Upper Cambrian)in northwestern Tarim Basin,China 认领
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作者 Yan-qiu Zhang Zeng-hui Guo Dai-zhao Chen 《中国地质(英文)》 2020年第3期425-444,共20页
Increasing interests in hydrocarbon resources at depths have drawn greater attentions to the deeply-buried carbonate reservoirs in the Tarim Basin in China.In this study,the cyclic dolomite rocks of Upper Cambrian Low... Increasing interests in hydrocarbon resources at depths have drawn greater attentions to the deeply-buried carbonate reservoirs in the Tarim Basin in China.In this study,the cyclic dolomite rocks of Upper Cambrian Lower Qiulitag Group from four outcrop sections in northwestern Tarim Basin were selected to investigate and evaluate the petrophysical properties in relation to depositional facies and cyclicity.The Lower Qiulitag Group includes ten lithofacies,which were deposited in intermediate to shallow subtidal,restricted shallow subtidal,intertidal,and supratidal environments on a carbonate ramp system.These lithofacies are vertically stacked into repeated shallowing-upward,meter-scale cycles which are further grouped into six third-order depositional sequences(Sq1 to Sq6).There are variable types of pore spaces in the Lower Qiulitag Group dolomite rocks,including interparticle,intraparticle,and fenestral pores of primary origin,inter crystal,and vuggy pores of late diagenetic modification.The porosity in the dolomites is generally facies-selective as that the microbially-originated thrombolites and stromatolites generally yield a relatively high porosity.In contrast,the high-energy ooidal grainstones generally have very low porosity.In this case,the microbialite-based peritidal cycles and peritidal cycle-dominated highstand(or regressive)successions have relatively high volumes of pore spaces,although highly fluctuating(or vertical inhomogeneous).Accordingly,the grainstone-based subtidal cycles and subtidal cycle-dominated transgressive successions generally yield extremely low porosity.This scenario indicates that porosity development and preservation in the thick dolomite successions are primarily controlled by depositional facies which were influenced by sea-level fluctuations of different orders and later diagenetic overprinting. 展开更多
关键词 DOLOMITES POROSITY CYCLICITY Upper Cambrian STROMATOLITE Microbial build up Oil-gas basin Oil-gas exploration engineering Tarim Basin China
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Modeling Stream Flow Using SWAT Model in the Bina River Basin, India 认领
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作者 Fitsum T. Teshome Haimanote K. Bayabil +1 位作者 L. N. Thakural Fikadu G. Welidehanna 《水资源与保护(英文)》 2020年第3期203-222,共20页
Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate th... Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate the performance of the Soil and Water Assessment Tool (SWAT) to simulate streamflow from the Bina basin in the Madhya Pradesh state of India. The SWAT model was calibrated and validated on a daily and monthly basis using historical streamflow and weather data from the Bina basin. The Sequential Uncertainty Fitting (SUFI-2) technique in the SWAT? Calibration and Uncertainty Procedures (SWAT-CUP) program was used to assess model uncertainties. The SWAT model performed “satisfactory” and “very good” in simulating streamflow at daily and monthly time steps, respectively. Model calibration results showed that coefficients of determination (R2) values were 0.66 and 0.96;while Nash-Sutcliffe (NSE) values were 0.65 and 0.94 for daily and monthly simulations, respectively. The R2 values of daily and monthly simulations during model validation were 0.65 and 0.72, respectively while the respective NSE values were 0.58 and 0.72. This study demonstrated that the SWAT model could be effectively used to simulate streamflow in the Bina river basin. 展开更多
关键词 MODELING Streamflow SWAT SWAT-CUP Bina River BASIN
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Re-examination of Hydrochemistry and Groundwater Potentials of Cross River and Imo-Kwa-Ibo Intersecting Tropical Basins of South-South Nigeria 认领
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作者 Saadu Umar Wali Ibrahim Mustapha Dankani +4 位作者 Sheikh Danjuma Abubakar Murtala Abubakar Gada Kabiru Jega Umar Abdulqadir Abubakar Usman Ibrahim Mohammad Shera 《地质研究(英文)》 2020年第3期25-42,共18页
This review attempted a detailed description of geological and hydrogeological configurations of Cross River and Imo-Akwa Ibo basins.It presented a synthesis of hydrochemistry and a description of the hydrogeological ... This review attempted a detailed description of geological and hydrogeological configurations of Cross River and Imo-Akwa Ibo basins.It presented a synthesis of hydrochemistry and a description of the hydrogeological configurations of the two basins.Hydrogeologically,most areas under Cross River and Imo-Kwa-Ibo are poor in terms of groundwater potentials.Based on the hydrochemistry,the basins hold water of excellent quality.Groundwater sources fall in soft to moderately hard classes.The entire sources groundwater has a TDS concentration of less than 500 mg/l.Groundwater classification based on electrical conductivity(EC)showed EC levels were less than 500μS/cm.Most of the examined cations and anions are within WHO reference guidelines for drinking water quality.However,no broad analysis of water quality based on water quality indices.Also,studies modeling pollution or the impact of land use changes on groundwater quality are wanting.Thus,further analysis of the hydrochemistry of groundwater aquifers is recommended. 展开更多
关键词 Cross River Basin Imo-Kwa-Ibo Basin HYDROGEOLOGY HYDROCHEMISTRY
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The Spatial and Temporal Characteristics of Rainfall over the Lake Victoria Basin of Kenya in 1987-2016 认领
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作者 Wabwire Odhiambo Evans S. N. Mukhovi I. A. Nyandega 《大气和气候科学(英文)》 2020年第2期240-257,共18页
Climate extremes have increased in the recent past and they are further being exacerbated by climate change and variability. In this paper, we sought to determine rainfall characteristics over the Lake Victoria Basin ... Climate extremes have increased in the recent past and they are further being exacerbated by climate change and variability. In this paper, we sought to determine rainfall characteristics over the Lake Victoria Basin of Kenya in 1987-2016, as a basis of understanding climate variability. The methodology used included;Standardized Precipitation Index to depict variability, coefficient of variation for spatial analysis and the Mann-Kendall test to test the presence of trends in data. We established that Lake Victoria basin is relatively wet through-out the year, with two distinct rainfall seasons March-April-May (MAM) and October-November-December (OND) that support human livelihood and ecology. The normal wetness conditions have declined over time, paving way for both dry and wet extremes conditions between 1997-1998 and 2002-2006, respectively. The rainfall extremes have become frequent in the last decade in 2007-2016. We also established a decline in the MAM rainfall seasons, and an increase during the October-December rainfall seasons in 1987-2016. Furthermore, the number of rainy days has declined with the onset and cessations of both long rains and short rains having shown a variability of at least 50% and 30% respectively, in a range of about 100 to 200 Julian days. The decline in wet condition is likely to affect economic activities especially the rainfed agriculture. The changing rainfall trends over the basin therefore, call for proper human livelihood planning and ecological monitoring in order to achieve ecological sustainability. 展开更多
关键词 Climate VARIABILITY SEASONAL RAINFALL Intra-Seasonal RAINFALL Characteritics and Lake VICTORIA BASIN
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Sequence Stratigraphy and Sedimentary Facies of Feixianguan Formation in the Kaijiang-Liangping Area of Sichuan Basin, China 认领
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作者 Qingbin Xie Zhifang Wang +4 位作者 Yongli Ouyang Miaoyi Zhang Bing Liu Lvli Wang Xiaojing Liu 《地质学期刊(英文)》 2020年第6期641-660,共20页
The Feixianguan formation in the Kaijiang-Liangping basin has been the focus of extensive research on multiple aspects. Based on field survey, core observation, laboratory analysis and seismic data interpretation, the... The Feixianguan formation in the Kaijiang-Liangping basin has been the focus of extensive research on multiple aspects. Based on field survey, core observation, laboratory analysis and seismic data interpretation, the sequence stratigraphy and sedimentary facies of the Kaijiang-Liangping area are studied. Four sequence boundaries and three maximum flooding surfaces of the Feixianguan formation are detected in this area. Three third-order sequences are identified as first sequence (SQ1), the second sequence (SQ2), and the third sequence (SQ3) in which SQ1 corresponds to the member 1 of the Feixianguan formation, SQ2 corresponds to the member 2, and SQ3 corresponds to the member 3 and member 4. Member 1, 2, 3 and 4 are lithologic sections divided by predecessors. On the basis of this sequence division and their sedimentary marks, the facies of the Feixianguan formation can be divided into open platform and evaporate platform categories. The open platform is composed of three subfacies identified as platform bank or basin marginal bank, interbank, and platform basin. Thus, a sedimentary evolution model is established. According to the sedimentary and seismic characteristics of the Kaijiang-Liangping area, we determine that two oolitic bank models, the aggradation model and the progradation model, are developed in this area. The aggradation model is developed in the Longgang region, which includes the basin marginal bank as a favorable exploring zone. The progradation model is developed in the Jiulongshan and Longhui areas, besides the basin marginal bank, the favorable exploration zones also include the oolitic bank developing areas of the inner basin. 展开更多
关键词 Sichuan Basin Kaijiang-Liangping Area Feixianguan Formation Sedimentary Facies
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About Engineering-Geonomic Research in the Zeravshan River Pool (Southern Tien Shan) in Connection with Climate Oscillations 认领
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作者 Alikhon Akhmadovich Karimov Narima Kazhenovna Ospanova 《地球科学和环境保护期刊(英文)》 2020年第5期387-394,共8页
Climatic anomalies not only attract the attention of specialists in climatology and meteorology, but also stimulate geological research, because climatic changes activate many geological processes: mudflow and landsli... Climatic anomalies not only attract the attention of specialists in climatology and meteorology, but also stimulate geological research, because climatic changes activate many geological processes: mudflow and landslide formation, erosion, weathering, etc. An increase in the activity of geological processes was clearly manifested in Tajikistan, 93% of which is occupied by mountain structures. As a result, this found expression in conducting new for that territory engineering-geonomic studies. Both the region as a whole and its individual parts can serve as models in the study of natural processes due to the diversity of landscape-climatic belts and zones. The report contains brief data on engineering-geonomic studies conducted in the Zeravshan river basin in connection with the intensification of mudflow processes. 展开更多
关键词 Climate Change MUDFLOW Formation Engineering-Geonomic Studies South-ern Tien Shan TAJIKISTAN Zeravshan RIVER Basin
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Geochemical Modeling and Statistical Analysis for Groundwater Evolution Assessment in Wadi Qasab, Sohag, Eastern Desert, Egypt 认领
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作者 Ehab Zaghlool 《地球科学和环境保护期刊(英文)》 2020年第9期33-61,共29页
Qasab basin is one of the most promising areas for the sustainable development in the Eastern Desert fringes of the Nile Valley, Egypt. The integration between statistical analysis, stable isotopes as well as geochemi... Qasab basin is one of the most promising areas for the sustainable development in the Eastern Desert fringes of the Nile Valley, Egypt. The integration between statistical analysis, stable isotopes as well as geochemical modeling tools delineated the geochemical possesses affecting groundwater quality and detected the main recharge source in Qasab basin. The most of groundwater samples are brackish (88%), while the minority (12%) of the samples are fresh. The electrical conductivity of groundwater ranged from 1135 to 10,030 μS/cm. The statistical analysis and hydrochemical diagrams suggest that the groundwater quality is mainly controlled by several intermixed processes (rock weathering and agricultural activities). The mineralization of the Pleistocene groundwater is regulated by the rock weathering source, evaporation processes and reverse cation exchange. The isotopic signatures (δ<sup>2</sup>H and δ<sup>18</sup>O) represent two groundwater groups. The first group, is enriched with the isotopic signature of δ<sup>18</sup>O, which ranges from 0.9‰ to 5.5‰. This group is mostly affected by the recent meteoric recharge from the surface water leakage. The second group, is relatively depleted with the isotopic signature of δ<sup>18</sup>O, reflecting a palaeo recharge source of colder climate. The δ<sup>18</sup>O‰ varies from <span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#45</span>10.1‰ to <span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#45</span>6.4‰, indicating upward leakage of the Nubian sandstone aquifer through deep seated faults. The inverse geochemical model reflects that the salinity source of the groundwater samples is due to the leaching and dissolution processes of carbonate, sulphate and chloride minerals from the aquifer matrix. This study can demonstrate the hydrochemistry assessment guide to support sustainable development in Qasab basin to ensure that adequate groundwater ma 展开更多
关键词 HYDROCHEMISTRY Statistical Analysis Stable Isotopes Inverse Geochemical Modeling and Qasab Basin EGYPT
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Analysis of Medicine Bow-Laramie River Drainage Divide Using Topographic Map Interpretation Techniques, Southeastern Wyoming, USA 认领
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作者 Eric Clausen 《地质学期刊(英文)》 2020年第7期741-759,共19页
Detailed topographic maps provide much of the information needed to understand how drainage divides like the southeast Wyoming Medicine Bow River-Laramie River drainage divide originated. Topographic map evidence for ... Detailed topographic maps provide much of the information needed to understand how drainage divides like the southeast Wyoming Medicine Bow River-Laramie River drainage divide originated. Topographic map evidence for each Medicine Bow-Laramie River drainage divide segment is here described and analyzed first using a commonly published interpretation (accepted paradigm) in which drainage routes developed on a surface of now mostly absent Oligocene and Miocene sediments that previous investigators have hypothesized to have once filled the Laramie Basin and to have also buried (or partially buried) the surrounding Laramie and Medicine Bow Mountains. Second, the same map evidence is analyzed using a recently proposed interpretation (new paradigm) in which massive and prolonged floods flowed across Wyoming as the Laramie and Medicine Bow Mountains began to be uplifted and as the southeast-oriented North Platte River valley eroded headward along the rising Laramie Mountains northeast flank. Low points along the drainage divide (referred to as divide crossings) are interpreted to be places where water once flowed across the drainage divide with the drainage divide being formed when capture events diverted the water in other directions. Valleys leading away from divide crossings are used to determine the nature of observed capture events, many of which are difficult or impossible to explain from the accepted paradigm perspective, but which are consistent with the mountain uplift, headward erosion of deeper valleys, and/or draining of floodwaters trapped in the Laramie Basin as the new paradigm predicts. However, the new paradigm requires a North American continental ice sheet heavy enough to raise entire regions and mountain ranges as massive and prolonged meltwater floods flowed across them, something the accepted paradigm does not recognize. 展开更多
关键词 Divide Crossing GEOMORPHOLOGY Laramie Basin Medicine Bow Mountains North Platte River
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Pore Structure Characteristics of Taiyuan Formation Shale in Qinshui Basin 认领
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作者 Hongyue Duan Wenkai Zhang +2 位作者 Xinquan Wang Kaizi Jiang Tingting Huang 《地球科学和环境保护期刊(英文)》 2020年第7期126-146,共21页
Qinshui Basin is located in the southeast of Shanxi Province, China. Taking the shale of Taiyuan Formation in Qinshui Basin as the research object, the study analyzed the pore size of the shale of Taiyuan formation in... Qinshui Basin is located in the southeast of Shanxi Province, China. Taking the shale of Taiyuan Formation in Qinshui Basin as the research object, the study analyzed the pore size of the shale of Taiyuan formation in detail from micropore to macropore by the methods of mercury injection, liquid nitrogen analysis and combination of liquid nitrogen and mercury injection. The results show that: 1) the visible pores and macropores are poorly developed and distributed unevenly in the shale of Taiyuan formation, and the micropores are well developed in the shale, and there are more open pores in the pore diameter range, and the pore connectivity is good;2) the liquid nitrogen experiment shows that the pores of Taiyuan Shale are relatively developed between 15 nm and 20 nm, and the formation of hysteresis loop may be caused by some narrow slit pores with similar layered structure;3) the comprehensive analysis of liquid nitrogen and mercury injection experiments shows that the shale of the Taiyuan formation mainly develops micropores, the Mesopores is not developed, the pore volume at 10 - 100 nm is more developed than other parts, and the specific surface is mainly contributed by micropores, which can improve the efficiency of shale gas resolution;at the same time, it provides a channel for Shale gas migration, which is beneficial to the development of shale gas. 展开更多
关键词 Qinshui Basin Taiyuan Formation SHALE Pore Structure Mercury Intrusion Method Liquid Nitrogen Method
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Apatite U–Pb dating and geochemistry of the Kyrgyz South Tian Shan(Central Asia): Establishing an apatite fingerprint for provenance studies 认领
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作者 Stijn Glorie Samantha March +6 位作者 Angus Nixon Fun Meeuws Gary J.O’Sullivan David M.Chew Christopher L.Kirkland Dmitry Konopelko Johan De Grave 《地学前缘:英文版》 SCIE CAS CSCD 2020年第6期2003-2015,共13页
This paper presents an apatite U-Pb and geochemistry archive for exposed plutons and metamorphic rocks of the Kyrgyz South Tian Shan(STS)within the Central Asian Orogenic Belt.Apatite U-Pb dates and trace-element geoc... This paper presents an apatite U-Pb and geochemistry archive for exposed plutons and metamorphic rocks of the Kyrgyz South Tian Shan(STS)within the Central Asian Orogenic Belt.Apatite U-Pb dates and trace-element geochemistry are provided for 17 samples from late Carboniferous-early Permian I-type granites in the Terktinsky complex and A-type granites in the Kokshaal Range;early Devonian granites in the Kembel complex;Cryogenian granitoids and tuffs from the Middle Tian Shan and gneisses from the Atbashi metamorphic complex.These samples form a comprehensive selection of igneous and metamorphic rocks within the cores of Mesozoic basement highs that supplied detritus to adjacent basins such as the Tarim,Ferghana and Yarkand-Ferghana Basins.Generally,the granitoid samples preserve primary igneous apatite U-Pb ages that are within uncertainty of previously published zircon U-Pb dates.The apatites from the Atbashi metamorphic complex record anomalous Ordovician dates with large uncertainties that are interpreted as mixing ages between Cryogenian protolith formation and Carboniferous metamorphism.Principal component analysis discriminates apatite samples from the different bedrock terranes in the Kyrgyz STS based on their geochemical fingerprint and categorizes the samples with respect to an extensive apatite geochemical archive.The combined apatite-zircon archive provides a novel framework for provenance studies on the Meso-Cenozoic sedimentary history of the Central Asian Orogenic Belt. 展开更多
关键词 Apatite provenance Central Asian Orogenic Belt Tian Shan Tarim Basin Ferghana Basin
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Organic Geochemical Evaluation of Shale Units of Bokh Formation, Ogaden Basin, Ethiopia 认领
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作者 Temesgen Oljira Matthew E. Nton Oluwadayo O. Sonibare 《地质学期刊(英文)》 2020年第5期565-578,共14页
Shale sample from Bokh Formation, Ogaden basin, Ethiopia was assessed for their petroleum potential by Rock-Eval pyrolysis. The Total Organic Carbon (TOC) values range from 0.76 to 0.86 wt%. These values exceed the mi... Shale sample from Bokh Formation, Ogaden basin, Ethiopia was assessed for their petroleum potential by Rock-Eval pyrolysis. The Total Organic Carbon (TOC) values range from 0.76 to 0.86 wt%. These values exceed the minimum value of 0.5 wt% required for potential petroleum source rocks. The genetic potential (GP) and hydrogen index (HI) values range from 0.09 to 0.5 mg/g and 8 - 32 mgHC/gTOC, respectively. These values are generally lower than the minimal 2 mg/g GP and 200 mgHC/g HI required for a potential source rock. Several plots from the Rock-Eval pyrolysis data classify the samples as type IV kerogen with no potential to generate hydrocarbons. The Tmax and Production Index (PI) values range from 388&deg;C to 453&deg;C and 0.28 to 0.46, respectively. These values indicate that the shales are thermally matured. These results show that the shales from the Bokh Formation in Ogaden basin have no potential to generate hydrocarbons mainly crude oil, but are thermally matured and may generate natural gas. 展开更多
关键词 Ogaden BASIN Bokh FORMATION SHALE HYDROCARBON Source ROCK
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