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991.
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993.
1830年磁县712级地震是一个活动水平高、持续时间长的强震序列。近年来邯郸遥测地震台网记录到沿磁县地震极震区方向发生的大量小地震。根据对这些小地震的震源位置、震源机制的三维空间分布的分析,认为磁县地震的震源断层是NWW向近于直立的左旋走滑断层,它和磁县地震的等震线、地表破裂带特征相符合。这个例子说明在地震学和地震地质学相结合的基础上,有可能由历史大地震区内现今小地震的群体特征,推测历史大地震的震源断层空间取向及其运动方式 相似文献
994.
Characteristics and forming mechanism of laminae fine-grained sedimentary rock of the Paleogene Funing Formation in Gaoyou and Jinhu sags,Subei Basin 下载免费PDF全文
The deep-water fine-grained deposits can be not only the source rock,but also the reservoir of unconventional oil and gas. Combined with high-precision centimeter-scale core observation,thin section identification,X-ray diffraction whole rock analysis,trace element test and scanning electron microscopy(SEM)analysis,the laminae characteristics and the genesis mechanism of semi-deep to deep lake fine-grained sedimentary rocks in the Member 2 of the Funing Formation are investigated in the Gaoyou and Jinhu sags of the Subei Basin. The results show that the semi-deep and deep lake fine-grained sedimentary rocks of the Member 2 of the Funing Formation in the Gaoyou and Jinhu sags are complex in lithology,and the laminae with different colors are formed by the mixture and superposition of various material components. The horizontal bedding developed in the fine-grained sedimentary rocks can be further divided into thin-laminated and thick-laminated sedimentary structures,whose macroscopic,microscopic characteristics and the composition are different. The complex forming mechanism of laminae includes two aspects: Formation process and preservation process. The generation(or the input)and the precipitation of each component have seasonal significance during the formation of laminae,whereas the preservation of the laminae could be mainly related to the water depth in the study area. 相似文献
995.
Research advances,geological implication and application in Ordos Basin of the “pore-size controlled precipitation” in diagenesis of carbonate rock reservoir 下载免费PDF全文
Based on the discovery of pore-size controlled mineral precipitation and cementation heterogeneity in carbonate rock reservoirs,the state of art and the geological implications are summarized,referring to the fluid-rock interaction and chemical hydrodynamics in porous media. (1)The pore-size controlled precipitation phenomenon is common in geological environments,as shown by the heterogeneous cementation and eventual features that the large pores are filled while small pores can be preserved. Related studies are mainly divided into three aspects,including pore structure observations at different scales,numerical simulation of fluid-rock interaction and mineral precipitation experiment. (2)The kinetic models related to surface chemistry can be used to explain the heterogeneous precipitation affected by pore-size distribution. The larger interfacial tension and mineral crystal curvature in the micropores result in the much higher effective solubility.Thus the fluids in micropores can maintain a higher supersaturation with no minerals precipitation. (3)The pore-size controlled precipitation leads to the selective preservation of micropores. It means that the much larger pores tend to be cement-filled while the smaller pores are preserved in the case of coexistence of pores at different scales. The impacts of cementation types on the overall permeability of rock are different. The pore-size controlled precipitation phenomenon is also worthy of attention in the research of geothermal development and geologic sequestration of carbon dioxide. In the last part, based on the heterogeneous cementation and porosity distribution of the Majiagou Formation in the Ordos Basin,we study the impacts of diagenetic fluids properties,origin and cementation patterns on the evolution of pore structure and high-quality reservoir distribution.The discovery and emphasis of pore-size controlled precipitation is of great theoretical significance to our understanding of the complex fluid-rock interaction process,which provides a new perspective for reservoir diagenesis and pore preservation. 相似文献
996.
浅层地震折射波法配合电测深法在花岗岩地区找水 总被引:4,自引:1,他引:3
通过在花岗岩地区十余年成功的找水实践,总结并提出一种简便而高效、具有很高成功率的常规综合物探方法,并通过3 个实例介绍了其应用效果。 相似文献
997.
从原始塔里木板块的演化入手,结合构造单元的划分,将巴丹吉林地区中生代地层划分为塔里木地层区的北山地层分区、阿拉善地层分区(包括北缘小区和南缘小区)和河西走廊地层分区,基本理顺了各分区(小区)中生代地层的命名系统,为研究各分区的沉积 构造古地理演化和恢复中生代原形盆地奠定了基础 相似文献
998.
兰州市大气飘尘的有机地球化学研究--Ⅱ.酮和醇脂类化合物的组成和分布特征 总被引:6,自引:0,他引:6
首次对兰州市大气飘尘中酮和醇脂类化合物进行了分析和研究。结果表明,兰州市大气飘尘中正烷基2酮和直链烷基醇的浓度分别为20~270ngm-3和520~910ngm-3,并表现为3月份高于7月和8月份,这与兰州市特殊的地形和气候条件有关;其分布特征指示了它们来自人为活动、微生物和现代高等植物,而且它们在这3种来源中所占的比例分别为2.8%~19.7%、15.4%~34.6%和50.3%~81.8%。甾醇化合物的浓度很低,它们由现代生物所提供。丰富的C18类异戊二烯酮化合物的存在,反映了大气飘尘中有机质在大气氧化过程中已经被改造。 相似文献
999.
1000.
可容空间与沉积环境变化对砂,砾岩自组织程度的影响 总被引:1,自引:0,他引:1
利用分开几何学原理研究了可容空间与沉积环境变化对砂、砾岩自组织程度的影响。通过研究表明,层序由水进体系域演化到高体系域,自组织程度不断降低。滩坝砂、砾岩沉积与辫状分流河道沉积的自组织程度相近;而盆底扇砂、砾岩体颗粒分布自组织程度较差。 相似文献