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陕西圣人桥附近,复杂多样的褶皱出现在平缓的地台盖层之中。对其成因,争议颇多,或认为推覆作用所致,或认为受断裂作用控制。笔者通过详细研究,认为这些复杂褶皱是一种水底重力滑塌构造。据此,还提出了重力滑动构造新的分类,即重力蠕滑;重力滑塌以及重力滑碎等三类。 相似文献
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北部湾盆地涠西南凹陷涠11区流一段扇三角洲沉积特征及控制因素 总被引：2，自引：0，他引：2
北部湾盆地涠洲11区流一段发育缓坡型和陡坡型两种类型的扇三角洲。结合岩电震资料,分析了这两类扇三角洲的异同,并探讨了造成这两类扇三角洲沉积特征异同的主控因素。其中陡坡型扇三角洲主要分布于研究区北部陡坡带的流一段中亚段,粒度较粗,以重力流成因的厚层砂砾岩体为主,沉积厚度大,平面展布小;而缓坡型扇三角洲主要分布于研究区南部的涠西南低凸起缓坡带附近的流一段下亚段,粒度相对偏细,牵引流与重力流沉积构造均较发育,沉积厚度相对较小,平面延伸范围广。两类扇三角洲形成与分布特征的不同主要受控于构造格局、古地形的差异以及基准面变化等。 相似文献
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伊拉克HF油田上白垩统Hartha组灰岩沉积在碳酸盐缓坡环境,储层发育特征及其主控因素尚不明确。通过钻井、测井、岩芯和地震资料,并结合薄片观察、分析化验,研究了该油田Hartha组的岩石学特征、储集空间特征及物性特征,并分析了沉积相和成岩作用对储层发育的控制。结果表明,厚度约50 m的Hartha组的储层岩石类型主要为粒泥灰岩、泥粒灰岩和颗粒灰岩,孔隙度10%～22%,渗透率集中在(0.1～0.5)×10^(-3 )μm^2和(1～5)×10^(-3 )μm^2,基质物性较好。Hartha组上段储集性能相对较好,Hartha组下段发育外缓坡灰泥,储集性较差。沉积作用对储层的物性起着主要控制作用,滩相储层的物性明显好于非滩相。该套灰岩的储集空间为粒间孔、铸模孔、生物体腔孔,以及粒内溶孔和微裂缝。晚白垩世暴露剥蚀期,在表生作用下Hartha A层溶孔部分被胶结物充填,存在局部的强烈胶结带。 相似文献
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中国微咸水资源化若干问题研究 总被引：17，自引：1，他引：16
中国水资源严重短缺,供求矛盾不断加剧,必须开发利用微咸水资源。该文在总结微咸水资源化必要性与可行性的基础上,阐述了微咸水资源化的途径,分析微咸水资源化对生态环境的影响,并提出了创建微咸水利用的高效生态模式、研究推广生态安全技术、加快配套技术、淡化技术研究等资源化策略。 相似文献
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Based on detailed field observation and multidisciplinary studies of integrated stratigraphy, the marine Lower and Middle
Triassic of Lower Yangtze region is divided into five third-order sequences, the general approach of the outcrop sequence
stratigraphical study of carbonate ramp is proposed, the pattern in the development of the Early and Middle Triassic sequence
under the major regression is summarized, and the sequence stratigraphical and chronostratigraphical frameworks across various
paleogeographical facies zones on the marginal platform are established.
Project supported by the Stake Key Project “SSLC” and the National Natural Science Foundation of China (Grant Nos. 49502022,
49632070). 相似文献
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Surface moisture area during rainfall–run‐off events to understand the hydrological dynamics of a basin in a plain region 
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下载免费PDF全文 María Guadalupe Ares Mauro Holzman Ilda Entraigas Marcelo Varni Luisa Fajardo Natalia Vercelli 《水文研究》2018,32(10):1351-1362
The understanding of the hydrology of plain basins may be improved by the combined analysis of rainfall–run‐off records and remote sensed surface moisture data. Our work evaluates the surface moisture area (SMA) produced during rainfall–run‐off events in a plain watershed of the Argentine Pampas Region, and studies which hydrological variables are related to the generated SMA. The study area is located in the upper and middle basins of the Del Azul stream, characterized by the presence of small gently hilly areas surrounded by flat landscapes. Data from 9 rainfall–run‐off events were analysed. MODIS surface reflectance data were processed to calculate SMA subsequent to the peak discharge (post‐SMA), and previous to the rainfall events (prev‐SMA), to consider the antecedent wetness. Rainfall–run‐off data included total precipitation depth (P), maximum intensity of rainfall over 6 hr (I6max), surface run‐off registered between the beginning of the event and the day previous to the analysed MODIS scene (R), peak flow (Qp), and flood intensity (IF). In contrast with other works, post‐SMA showed a negative relationship with the R. Three groups of cases were identified: (a) Events of low I6max, high prev‐SMA, and low R were associated with slow and weakly channelized flow over plain areas, leading to saturated overland flow (SOF), with large SMA; (b) events of high I6max, low prev‐SMA, and medium to high R were rapidly transported along the gentle slopes of the basin, related to Hortonian overland flow (HOF) and low post‐SMA; and (c) events of medium to high I6max and prev‐SMA with medium R were related to heterogeneous input‐antecedent‐run‐off conditions combined: Local spatial conditions may have produced HOF or SOF, leading to an averaged response with medium SMA. The interactions between the geomorphology of the basin, the characteristics of the events, and the antecedent conditions may explain the obtained results. This analysis is relevant for the general knowledge of the hydrology of large plains, whose functioning studies are still in their early stages. 相似文献
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