The origin and accumulation model of crude oils from oil reservoirs Chang 9 and Chang 10 in the Yanchang Formation of the Ordos Basin     

Junping Huang  Xiangbo Li  Qilin Chen  Zhanlong Yang  Yanrong Wan  Lihua Wei  Liwen Long  Xiaoguang Liu 《中国地球化学学报》2012,31(3):327-339

In the lower parts of oil reservoirs Chang 9 and Chang 10 of the Yanchang Formation are oil-bearing layers newly found in oil exploration in the Ordos Basin.Based on GC,GC-MS analyses of saturated hydrocarbons from crude oils and source rocks,reservoir fluid inclusions and BasinMod,the origin of crude oils,accumulation period and accumulation models are discussed in combination with other petroleum geology data in this paper.The result shows that(1) there are two different types of crude oils in oil reservoir Chang 9 in the Longdong and Jiyuan regions:crude oils of typeⅠ(Well D86,Well A44,Well A75,Well B227,Well X62 and Well Z150) are mainly de-rived from the Chang 7 source rocks(including mudstones and shales) and distributed in the Jiyuan and Longdong regions;those of typeⅡ(Well Z14 and Well Y427),are distributed in the Longdong region,which are derived from the Chang 9 source rocks.Crude oils from oil reservoir Chang 10 in the Shanbei region are mainly derived from the Chang-9 source rocks;(2) there are two phases of hydrocarbon filling in oil reservoir Chang 9 in the Jiyuan and Longdong regions and oil reservoir Chang 10 in the Shanbei region:The first phase started at the early stage of J2z.The process of hydrocarbon filling was discontinuous in the Late Jurassic,because of the tectonic-thermal event in the Ordos Basin.The second phase was the main accumulation period,and hydrocarbons began to accumulate from the late stage of J2a to the middle-late of K1,mainly at the middle-late stage of K1;(3) there exist two types of accu-mulation models in oil reservoirs Chang 9 and Chang 10 of the Yanchang Formation:source rocks of the reservoirs in oil reservoir Chang 9 in the Jiyuan region and oil reservoir Chang 10 in the Shanbei region,the mixed type of reservoirs on the lateral side of source rocks and source rocks of the reservoirs in oil reservoir Chang 9 in the Long-dong region.  相似文献   

Spatial analysis of a historical phenomenon: using GIS to demonstrate the strategic placement of Umayyad desert palaces   总被引：1，自引：0，他引：1  

Mahmoud Bashir Alhasanat  Shahid Kabir  Wan Muhd Aminuddin Wan Hussin  Erin Addison 《GeoJournal》2012,77(3):343-359

The Umayyad qusour (desert palaces) are monumental structures built during the reign of the first caliphate of Islam. Usually dismissed as “pleasure palaces” or “hunting lodges,” some scholars are beginning to argue that these prominent structures were strategic interventions in the landscape. Until now, historians have relied mainly on textual, architectural and art-historical analyses of the qusour in order to understand Umayyad state architecture. This research proposes the use of spatial analysis through GIS to lend a new dimension to the discussion. The results of the analysis show that Umayyad qusour are carefully situated at routes of transhumance and water sources. The distribution pattern of the Umayyad qusour is clustered at the outlet of Wadi Sarhan, and there is actually line-of-sight communication between Azraq, Amra, Haranah, Muwaqqar, Umm al Walid, Mushatta, and Qastal. There is also a positive association between Umayyad qusour and their water sources. These results support the argument that the Umayyad qusour were built strategically at perennial water sources in order to monitor routes of transhumance amongst the socio-political centers of the period.  相似文献   

An artificial neural network model for flood simulation using GIS: Johor River Basin, Malaysia   总被引：7，自引：2，他引：5  

Masoud Bakhtyari Kia  Saied Pirasteh  Biswajeet Pradhan  Ahmad Rodzi Mahmud  Wan Nor Azmin Sulaiman  Abbas Moradi 《Environmental Earth Sciences》2012,67(1):251-264

Flooding is one of the most destructive natural hazards that cause damage to both life and property every year, and therefore the development of flood model to determine inundation area in watersheds is important for decision makers. In recent years, data mining approaches such as artificial neural network (ANN) techniques are being increasingly used for flood modeling. Previously, this ANN method was frequently used for hydrological and flood modeling by taking rainfall as input and runoff data as output, usually without taking into consideration of other flood causative factors. The specific objective of this study is to develop a flood model using various flood causative factors using ANN techniques and geographic information system (GIS) to modeling and simulate flood-prone areas in the southern part of Peninsular Malaysia. The ANN model for this study was developed in MATLAB using seven flood causative factors. Relevant thematic layers (including rainfall, slope, elevation, flow accumulation, soil, land use, and geology) are generated using GIS, remote sensing data, and field surveys. In the context of objective weight assignments, the ANN is used to directly produce water levels and then the flood map is constructed in GIS. To measure the performance of the model, four criteria performances, including a coefficient of determination (R ²), the sum squared error, the mean square error, and the root mean square error are used. The verification results showed satisfactory agreement between the predicted and the real hydrological records. The results of this study could be used to help local and national government plan for the future and develop appropriate (to the local environmental conditions) new infrastructure to protect the lives and property of the people of Johor.  相似文献   

Resilient and plastic strain behavior of freezing–thawing mucky clay under subway loading in Shanghai     

Yiqun Tang  Jun Li  Peng Wan  Ping Yang 《Natural Hazards》2014,72(2):771-787

Depending on artificial freezing method applied in subway tunnel construction, a series of stress-controlled cyclic triaxial tests were conducted on freezing–thawing mucky clay to investigate their resilient and plastic strain behavior. In terms of practical engineering, this study focuses on three significant influencing factors which are artificial freezing temperatures, dynamic stress amplitude and loading frequency. This study demonstrates how these influence factors effect on the resilient strain or dynamic elastic modulus and accumulated plastic strain which are crucial to better understanding the strain behavior of freezing–thawing soil. The results indicate that the value of freezing temperature has slight influence on dynamic elastic modulus, but the freeze–thaw action can truly decrease the dynamic elastic modulus of soil, and soil with higher freezing temperature possesses larger accumulated axial strain. Besides, the dynamic elastic modulus decreases remarkably with the increasing of the cyclic stress amplitude, while the accumulated plastic strain behaves adversely. In addition, loading frequency has the least effect compared with other two factors, but lower frequency can generate larger accumulated plastic strain.  相似文献   

创业者区位选择的家乡偏好及其驱动机制     

孙斌栋  崔莹雪  李琬 《地理研究》2022,41(6):1513-1524

作为家乡认同感浓厚且出现大规模流动人口的转型中国家,中国的创业者在区位选择上究竟偏好家乡还是异地亟待回答,这关乎地方创业政策的方向性布局。基于2014年中国劳动力动态调查数据,从微观个体层面实证检验了创业者在区位选择上是否存在家乡偏好,并探究了其驱动机制。研究发现：创业者在区位选择上的确存在家乡偏好,且这种偏好在生存型和机会型的创业者中均普遍存在;在剔除可能造成家乡偏好高估的样本后,上述发现依然成立。进一步的机制分析发现,创业者偏好在家乡创业是为了借助熟悉的社会网络拓展营销渠道并照顾子女和父母。上述发现为制定创业人才政策提供了科学依据。  相似文献   

中国大陆科学钻探主孔正片麻岩磁性及深部流体活动          下载免费PDF全文

曾庆理  刘庆生  郑建平  刘志峰  王红才 《地球科学》2014,39(12):1915-1926

通过对中国大陆科学钻探工程主孔花岗质片麻岩进行详细的岩石磁学研究及岩石矿物学分析表明: 花岗质片麻岩磁化率(0.570×10-7~120.450×10-7m3·kg-1, 平均29.996×10-7m3·kg-1)在主孔所有岩石中仅次于蛇纹石化石榴石橄榄岩, 而其天然剩余磁化强度(0.002×10-3~2.109×10-3Am2·kg-1, 平均0.210×10-3Am2·kg-1)则是所有岩性中最低的.磁化率随温度变化曲线、交变退磁曲线及磁滞回线特征表明, 花岗质片麻岩中磁性矿物组合主要成分为磁铁矿, 小部分样品中含有赤铁矿, 其中磁铁矿以多畴为主, 伪单畴磁铁矿仅在少量样品中出现.和同为完全退变质岩的角闪岩(完全退变质榴辉岩)相比, 花岗质片麻岩具有相似的磁性矿物组合, 但其磁铁矿的颗粒明显较大.多畴磁铁矿的形成, 可能和超高压变质岩折返过程中, 花岗质片麻岩较强的流体活动相关.部分分布于花岗质片麻岩主体岩性段外的样品, 具有较高的天然剩余磁化强度, 则可能反映了花岗质片麻岩及周围榴辉岩之间的流体交换.   相似文献   

致密储层油气成藏机理研究现状及其关键科学问题   总被引：4，自引：0，他引：4  

曾溅辉  杨智峰  冯枭  乔俊程  张忠义 《地球科学进展》2014,29(6):651-661

致密油气是世界上近20年来勘探、开发和研究的热点。在大量文献资料调研的基础上,首先总结了前人对致密储层特征及成因、致密储层油气形成和分布特征以及致密储层油气运移和聚集机理等方面的研究现状;然后分析了目前国内外有关致密储层油气成藏研究的主要特点;最后提出微米—纳米级孔喉网络系统油气充注、运移和聚集机理是致密储层油气成藏机理的核心科学问题,具体体现为油气由烃源岩向致密储层的充注机理、致密储层微米—纳米级孔喉网络系统油气运移的渗流机理以及致密储层微米—纳米级孔喉网络系统油气的赋存和聚集(滞留)机理3个具体的关键科学问题,而这将是致密储层油气成藏机理下一步研究的重点。  相似文献   

“一体化成井技术”在施工降水中的应用研究     

冯科明  马健  万家和 《岩土工程技术》2014,(4):188-192

北京西部卵石地层常采用冲击钻进工艺成井,机械体积大、成孔时间长、洗井质量差、对地面交通影响大,成井过程中产生的泥浆对环境影响较大.“一体化成井技术”采用风动潜孔锤成孔,跟进钢制井管一次成井.该工法具有成孔效率高、不用制备泥浆、不用专门洗井,施工占地较小、灵活等特点,尤其在改善环境及交通方面优势明显.介绍了该工艺在北京地铁降水工程中的应用,探讨了一套完备的一体化成井技术,经近两年多的施工实践,充分表明对类似工程具有很好的参考价值.  相似文献   

Fine-Scale Detection of Estuarine Water Quality with Managed Freshwater Releases     

Christopher Buzzelli  Brian Boutin  Mayra Ashton  Barbara Welch  Patricia Gorman  Yongshan Wan  Peter Doering 《Estuaries and Coasts》2014,37(5):1134-1144

Freshwater pulses to subtropical estuaries often occur on time scales less than 1 week. In particular, introduction of low-level pulses are potentially important during the dry season (November–April) when freshwater is scarce. Determining potential ecological benefits of pulses requires an innovative method of data acquisition at the appropriate spatial and temporal scales. The South Florida Water Management District conducted a pilot study to assess changes in water column attributes with pulse releases to the Caloosahatchee River Estuary (CRE) from January to April 2012. An average inflow of 450 cfs was targeted for a series of freshwater pulses. This study utilized an onboard, flow-through system to record surface water temperature, salinity (S), pH, dissolved oxygen, turbidity, and in situ chlorophyll a (in situ CHL) at 5 s intervals along the 42-km length of the estuary. On each of seven research cruises, the vessel stopped at multiple stations to conduct vertical water column profiles. Salinity increased throughout the CRE as inflow decreased during the study period. Simple correlation and partial least squares regression were used to determine that the downstream locations of the S?=?10 isohaline and the maximum CHL concentration (in situ CHL_max) were positively related to inflow. While the in situ CHL_max was located 12–20 km downstream on five of the cruises, it was only a few kilometer from the estuary head on the first (1/12) and last (4/11) dates. It is possible that two circumstances related to freshwater inflow accounted for this pattern. First, water column stratification before January could have stimulated remineralization and primary production. Second, inflow ceased as water temperature increased to 26.0 °C by April to promote algal growth. Further study of the relationships among inflow, water level, flushing time, and CHL is warranted. Future efforts will examine the range of wet season discharge by incorporating a sensor for colored dissolved organic matter to fully connect inflow, salinity, submarine light, and phytoplankton attributes in the CRE.  相似文献   

An analytical study on groundwater flow in drainage basins with horizontal wells   总被引：3，自引：1，他引：2  

Jun-Zhi Wang  Xiao-Wei Jiang  Li Wan  Xu-Sheng Wang  Hailong Li 《Hydrogeology Journal》2014,22(7):1625-1638

Analytical studies on release/capture zones are often limited to a uniform background groundwater flow. In fact, for basin-scale problems, the undulating water table would lead to the development of hierarchically nested flow systems, which are more complex than a uniform flow. Under the premise that the water table is a replica of undulating topography and hardly influenced by wells, an analytical solution of hydraulic head is derived for a two-dimensional cross section of a drainage basin with horizontal injection/pumping wells. Based on the analytical solution, distributions of hydraulic head, stagnation points and flow systems (including release/capture zones) are explored. The superposition of injection/pumping wells onto the background flow field leads to the development of new internal stagnation points and new flow systems (including release/capture zones). Generally speaking, the existence of n injection/pumping wells would result in up to n new internal stagnation points and up to 2n new flow systems (including release/capture zones). The analytical study presented, which integrates traditional well hydraulics with the theory of regional groundwater flow, is useful in understanding basin-scale groundwater flow influenced by human activities.  相似文献