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1.
硬玉是单斜辉石中十分重要的端元组分,是单斜辉石分类的主要基础。利用x射线衍射分析确定的硬玉组分含量计算式为Jd(%)=[A-2.235]×25.741,其中Jd为硬玉组分百分含量,A为2—Theta角为30°(d=2.97)时峰值的相对强度Ⅰ与半高宽的乘积,其计算误差仅6.32%。  相似文献   
2.
Through field geological survey,the authors found that abundant thrust faults developed in the Longmen (龙门) Mountain thrust belt.These faults can be divided into thrust faults and strike-slip faults according to their formation mechanisms and characteristics.Furthermore,these faults can be graded into primary fault,secondary fault,third-level fault,and fourth-level fault according to their scale and role in the tectonic evolution of Longmen Mountain thrust belt.Each thrust fault is composed of several secondary faults,such as Qingchuan (青川)-Maowen (茂汶) fault zone is composed of Qiaozhuang (乔庄) fault,Qingxi (青溪) fault,Maowen fault,Ganyanggou (赶羊沟) fault,etc..The Longmen Mountain thrust belt experienced early Indosinian movement,Anxian (安县) movement,Yanshan (燕山)movement,and Himalayan movement,and the faults formed gradually from north to south.  相似文献   
3.
When organic matter during geological processes is affected by a variety of factors such as paleotemperature, and time, complicated chemical reactions will occur, finally resulting in the generation of petroleum and natural gas. These reactions leading to…  相似文献   
4.
对鄂尔多斯盆地中部气田天然气碳同位素资料按不同地区、不同层位进行了分析,认为奥陶系风化壳气藏甲烷碳同位素值与石炭-二叠系气藏的接近,在平面上变化趋势相似,而与风化壳之下奥陶系自生自储的油型气相差较大。奥陶系风化壳气藏的来源是以石炭-二叠系煤成气为主,定量计算表明,在中部气田的大部分地区,石炭-二叠系来源气的比例大于70%。  相似文献   
5.
Comparison of Kuqa foreland basin with Persian Gulf Basin in salt tectonics   总被引:1,自引:0,他引:1  
Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective.  相似文献   
6.
Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective.  相似文献   
7.
青藏高原具有复杂的构造演化特征,该地区自中、新生代以来的构造隆升和构造演化机制一直是地质研究的热点。为精细刻画青藏高原板块、华北板块和华南板块之间的拼合关系及差异性隆升特征,对位于青藏高原东北端的碧口地块进行了磷灰石和锆石裂变径迹测试,以及热史模拟和岩石冷却速率计算。结果锆石和磷灰石裂变径迹年龄分别在(118±5~265±29)Ma和(29.0±2.7~54.0±7.0)Ma之间;碧口地块东北缘及北缘冷却速率接近,在3.125~3.448 ℃/Ma之间,东缘冷却速率相对较低,为2.041~2.273 ℃/Ma。结果表明,中、新生代以来,碧口地块及其周缘总体上经历了持续隆升过程,但不同地区隆升特征具有差异性:碧口地块北侧在早、中侏罗世(151±7)Ma经历了构造挤压和隆升过程;东部相对较晚,在晚侏罗世(143±11)Ma经历了构造隆升阶段;东北端在早白垩世才与华北板块拼接并进入持续构造隆升阶段。进入古近纪(54.0±7.0)Ma隆升阶段,即始新世早期后,碧口地块东缘在始新世中后期(44 Ma)开始发生构造隆升,北缘自渐新世中晚期(29~32 Ma)开始发生显著的构造隆升。上述区域在10 Ma(中新世晚期)共同进入快速隆升阶段。  相似文献   
8.
Geotechnical and Geological Engineering - To study the influence of changes in the coal seam mechanical characteristics at depth on the stress relief effect of a borehole, this paper established...  相似文献   
9.
以欠驱动自主水下机器人(Autonomous Underwater Vehicle,AUV)为试验平台,提出了一种水平面动力定位控制方法。根据自研 AUV 平台的运动执行机构配置,针对其欠驱动特性设计运动控制器,控制纵向推力与转艏力矩,经过路径跟踪与区域镇定两个阶段,使航行器先沿预设路径快速接近目标点,再低速逐渐调整水平位置,最终在该点附近小范围内保持悬停。结合试验数据证明:航行器可抵达并稳定在目标点附近 2 m 范围内,并且在受到外力扰动偏离后能够重新返回,从而验证该动力定位控制方法的有效性。  相似文献   
10.
Wei  Xiu  Liu  Wenzheng  Lin  Xuyin  Liu  Qianchun  Jiang  Peng 《中国海洋湖沼学报》2022,40(6):2343-2353
Journal of Oceanology and Limnology - Molecular investigations have raised concerns about the ecological risks of green tides caused by alien Ulva species in new habitats. The green tide-forming...  相似文献   
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