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91.
戴伟铭 《吉林大学学报(地球科学版)》2010,(Z1)
功率谱方法在磁数据处理方面的应用比较广泛。采用近似公式直接求出地质体的上下底埋深。在此近似方法中,会出现一些影响结果的因素。主要对地质体的水平尺寸和厚度的影响做了一些研究,并得出相应的结论。 相似文献
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对河南省不同区域的煤系地层反射波发育特点进行分析研究、归类总结和正反演对比,建立了地震波-地质层位的对应关系,有利于解释人员从时间剖面上准确分辨出新生界、煤系地层和煤系基底反射波组,确定煤层反射波及煤层赋存状况,为类似地区的地震资料解释工作提供科学的指导。 相似文献
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95.
贵州织金新华含稀土磷矿床稀土元素地球化学及生物成矿基本特征 总被引:15,自引:0,他引:15
对贵州织金新华含稀土磷矿床进行的稀土元素及微量元素分析结果表明,磷块岩中普遍富集稀土元素,稀土总量∑REE较高,并富集Y元素及La,Nd等轻稀土元素。LREE/HREE比值较高。含稀土磷块岩普遍具Ce负异常,显示其对源区的继承性。指示成磷环境处于氧化程度相对较高状态。稀土元素球粒陨石标准化模式曲线、北美页岩标准化模式曲线、Ce元素异常、LREE/HREE比值、微量元素特征及岩石矿物特征表明,织金新华含稀土磷矿床具以正常海相生物-化学沉积等为主伴有海相热水沉积混合成因的特征。在磷矿成矿过程中沉积物沉积时,活体生物及死亡残骸不同程度地摄取和富集了La,Nd,Ce等稀土元素、Y元素及其他微量元素,沉积在含磷层位,构成大量的含稀土、含生物碎屑白云质磷块岩。 相似文献
96.
Types of Enclaves and Their Features and Origins in Intermediate-Acid Intrusive Rocks from the Tongling District, Anhui Province, China 总被引:9,自引:0,他引:9
WU Cailai WANG Zhihong QIAO Dewu LI Haibing HAO Meiying SHI Rendeng Institute of Geology Chinese Academy of Geological SciencesXi''an Engineering College Geological Mechanics Institute CAAGS 《《地质学报》英文版》2000,74(1):54-67
Enclaves in intermediate-acid plutons from Tongling can be divided into three types: xenoliths, relics and magmatogenic enclaves. The magmatogenic enclaves consist of cumulates, micrograined dioritite mixtite and dioritic chilled border enclaves. Petrologically, relics with eyed and meta-poikilitic texture are characterized by high content of biotite (>80%) and low content of cordierite and grossular. The cumulates with accumulate texture consist of a great amount of pyroxene, hornblende and minor spinel and phlogopite. The micrograined dioritic mixtite is composed of more hornblendes and feldspar and less needle apatites and an ellipsoid basic core included in plagio-clase. The chilled border enclaves have the same mineral association, but more dark minerals than the host rocks consisting of plagioclase, quartz, alkaline feldspar, hornblende and biotite. Geochemically, the relics exhibit high REE content (455.8×10-6) and high ratio of LREE/HREE, more obvious Eu negative anomaly and are rich in Cr and 相似文献
97.
针对油田局域网的特点,利用网络存储技术中的SOCKET编程方法,结合Linux或Unix系统中的常驻进程及输入输出控制技术解决海量地震数据交换的问题,这个方法可以实现远程磁带或磁盘数据的读取。对常用的地震数据SEGY格式及其存储特点进行分析,在SEG-Y格式的地震数据的读写技术中,采用位运算的方式解决移位及浮点数的读写操作。网络存储技术的应用实现了远程海量地震数据的存取,位运算方法提高了地震数据输入输出的速度。 相似文献
98.
YANG Xinglian ZHU Maoyan GUO Qingjun ZHAO Yuanlong 《《地质学报》英文版》2007,81(2):194-203
Secular variations of carbon isotopic composition of organic carbon can be used in the study of global environmental variation, the carbon cycle, stratigraphic delimitation, and biological evolution, etc. Organic carbon isotopic analysis of the Nangao and Zhalagou sections in eastern Guizhou reveals a negative excursion near the Precambrian-Cambrian boundary that correlates with a distinct carbonate carbon isotopic negative excursion at this boundary globally. Our results also demonstrate that several alternating positive and negative shifts occur in the Meishucunian, and an obvious negative anomaly appears at the boundary between the Meishucunian and Qiongzhusian. The isotope values are stable in the middle and lower parts but became more positive in the upper part of the Qiongzhusian. Evolution of organic carbon isotopes from the two sections in the deepwater facies can be well correlated with that of the carbonate carbon isotopes from the section in the shallow water facies. Integrated with other stratigraphic tools, we can precisely establish a lower Cambrian stratigraphic framework from shallow shelf to deep basin of the Yangtze Platform. 相似文献
99.
SUN Aiqun NIU Shuyin SHAO Ji''an HOU Quanlin ZHANG Jianzhen Shijiazhuang College of Economics Shijiazhuang Hebei School of Earth Space Sciences Peking University Beijing Institute of Geology Geophysics Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(1):283-290
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materi 相似文献
100.
Peijian Shi Jie Liu Zhen Yang Agricultural College Jiangxi Agricultural University Nanchang China China Earthquake Networks Center Beijing China 《地震学报(英文版)》2009,(3):231-237
For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aftershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershoc... 相似文献