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31.
东营凹陷牛庄洼陷沙河街组发育有超压系统,这对油气运移和聚集过程有着重要的影响。在对超压系统现今发育特征研究的基础上,本文运用约束下数值模拟方法对牛庄洼陷超压系统的演化规律进行研究,并探讨了超压系统的主要形成机制。牛庄洼陷在沙河街组四段、沙河街组三段的下亚段和中亚段存在着超压系统,最大压力系数可以达到1.8,最大剩余压力超过了20MPa。自沙三段上亚段沉积期开始,超压系统开始发育。到东营组沉积期末,超压系统经历了大约10Ma的泄压过程。自新近系馆陶组沉积期,超压系统再次迅速增压,逐渐接近现今发育状况。上覆地层沙三段上亚段高沉积速率导致了超压系统的形成和早期剩余压力的增加,而水热增压和烃类物质大量生成联合造成超压系统晚期迅速增压。超压系统演化规律揭示出在油气主要运移期研究区古异常流体压力的分布状况,这为进一步开展牛庄洼陷油气运移和聚集过程的动力学研究提供了理论依据。 相似文献
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A new record of a flathead fish (Teleostei: Platycephalidae) from China based on morphological characters and DNA barcoding 总被引:2,自引:0,他引:2
A new record of Platycephalus sp.1 (sensu Nakabo, 2002) was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp.1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit (COI) gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp.1 was 0.1%. Net evolutionary distances between Platycephalus sp.1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COI sequence analysis strongly supports the validity of Platyceohalus sp.1 at genetic level. 相似文献
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Shuya Hu Changlai Xiao Xiujuan Liang Quansheng Zhao Guangcai Wang Jianwei Zhang Juan Feng 《中国地理科学(英文版)》2018,28(4):707-716
Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth. 相似文献
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37.
金翅岭金矿是胶东招远北部的一个典型石英脉型金矿,构造是金矿最为重要的控矿因素。在前人资料的基础上,综合分析了矿区构造控矿特征,总结了构造控矿规律:矿脉分支复合,表现为NE向矿脉产生SN,NNE向次级矿脉,NNE向矿脉产生NE向次级矿脉;矿体厚度与金品位呈负相关,深部次级矿脉群在P4脉下盘出现;矿脉侧伏角和倾伏向变化处矿体富集,表现为SW向侧伏的P4矿脉,矿体富集于-240 m,侧伏角变大,同时倾伏向由SW向转变为NW向的部位。最后建立了平面和剖面P4矿脉的波形函数,并对深部进行了预测。 相似文献
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本文从当前平顶山市矿业特点及引发的问题出发,着重指出实现矿业经济可持续发展,必须加大矿业结构的调整,并从资源管理方式、资源配置、矿业秩序、地勘工作等方面作了较为详细的论述。 相似文献
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随着水库在经济社会发展中所起的作用日趋明显,对水库的开发、治理更加重视,获取高精度的水库水下地形数据变得更加急迫.随着测深技术、差分GNSS技术以及姿态传感器的不断发展,基于GNSS的测深系统为水下地形测量提供了全新的解决方案.通过合理规划测线,经过声速改正、吃水改正,利用船载GNSS导航定位和测深仪采集测深数据,经转... 相似文献