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991.
Lunnan region is a large-scale paleohigh with many coexisting oil and gas bearing series. At present, about 2 billions tons of proved, probable and possible oil and gas reverses have been proved there. Eight oil and gas bearing series have been found in the Ordovician, Carboniferous, Triassic and Jurassic of Lunnan region, they all bear the characteristics of large-scale multilayer oil-gas province. Ordovician is the main reservoir series where over 0.8 billion tons of oil geologic reserves were discovered, and a super large-scale marine carbonate oil and gas field has formed. Reservoir space of the carbonate reservoirs is mainly composed of dissolved hole, dissolved pore and fracture in Lunnan paleo-burial hill. Generally, dissolved holes are widely distributed among them. Reservoir developments are mainly controlled by karstification and tectonic disruption. Due to the similar geochemical characters, the Ordovician, Carboniferous, Triassic and Jurassic oil and gas reservoirs present the same oil source rock of Mid-Upper Ordovician, the latter except Ordovician are mostly of secondary oil and gas reservoirs migrated vertically by faults during the process of multiple phase tectonic movement, adjustment and reconstruction. Lunnan composite oil and gas accumulation region is situated in the vicinity of large-scale hydrocarbon generation depressions in three directions, ample oil and gas from hydrocarbon generation depressions supplied the adjacent oil and gas reservoirs once. Hereby, the succeed paleohigh is the long-term hydrocarbon accumulation region, which is favor for the formations of high quality reservors, fault systems and huge-scale composite oil and gas accumulation.  相似文献   
992.
To simultaneously take into account the Biot-flow mechanism, the squirt-flow mechanism, and the frame-viscoelasticity mechanism, a generalized viscoelastic BISQ (Biot/squirt) model is developed for wave propagation in clay-bearing sandstones based on Dvorkin's elastic BISQ model. The present model is extended to a wide range of permeabilities (k 〉 0.05 mD) by introducing a dimensionless correction factor for viscoelastic parameters, defined as a function of the permeability and the clay content. We describe the frame's stress-strain relationship of the clay-bearing sandstones by the differential constitutive equations of generalized viscoelasticity and then derive the viscoelastic-wave dynamic equations. With the assumption of a plane-wave solution, we finally yield the phase velocities and the attenuation coefficients by solving the dynamic wave equations in the frequency and wave number domain. The comparison of numerical results and experimental data shows that the generalized viscoelastic BISQ model is applicable for modeling the wave propagation in most of the sandstones mainly bearing kaolinite clay.  相似文献   
993.
The characteristics of seismic water level fluctuations of the two Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 on December 26,2004 and March 29, 2005 recorded at Jiaji well, Qionghai, Hainan were analyzed, the features of the infrequent "step" changes of well water level after the two earthquakes were also analyzed and the mechanism of the "step change" of well water level was discussed. Then the high-sample-rate digital observation data of seismically-induced water level fluctuations of the Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 recorded at Nanbin well, Sanya and Tanniu well, Wenchang were analyzed. The results suggest that the dominant period of the seismic well water level fluctuation in all three wells was comparatively accordant, the amplitudes of seismic water level fluctuation of the same earthquake in different wells were clearly different, the time duration of seismic water level fluctuations of different earthquakes at the same well was also clearly different.  相似文献   
994.
运用速率法、滑动傅氏对新沂地震台(以下简称新沂台)1990-1999年地电阻率观测资料进行了分析,1994年到1997年之间江苏及邻近地区发生的中强震,新沂台地电阻率3个测向有不同程度的异常与之对应。研究结果表明资料异常呈现的各向异性与孕震期的应力状态、震区构造、介质结构有关。表明了前兆异常的复杂性、多样性。  相似文献   
995.
通用地震数据采集器EDAS-24GN引入一种新型的数据传输方式,通过AT91SAM9263CPU板带有的同步串行控制器进行数据传输,可以有效解决前一种方式存在的问题.经过实验验证,新型的数据传输方式在每秒传输50 kB数据时,引起的中断次数只有十几次,有效提高了CPU处理效率,且不存在数据丢失现象.  相似文献   
996.
在医用X-CT中,散射现象对重建图像的质量有重要的影响。多源锥束CT是医用CT的一种发展趋势,可成倍提高时间分辨率。但与单源CT相比,多源CT额外的光源会导致散射现象的加重,因此在实际应用中需要着重考虑这一问题。本文在开源工具EGSnrc的基础上,开发了一套基于蒙特卡罗法的CT仿真软件SimProj,用该软件获得了贴近...  相似文献   
997.
刘阳 《高原地震》2012,24(3):26-29
依据中国地震局地下流体学科技术协调组制定的《地下流体观测站(点)质量与效能评估方案》,从5个方面对海南省地下流体3个固定观测网三大测项的监测效能进行了评估,较全面地分析了海南地震地下流体监测网存在的问题,并针对存在问题提出了建议性的改进措施。  相似文献   
998.
地下核爆炸地震波二次源特征   总被引:3,自引:1,他引:3       下载免费PDF全文
层裂是地下核爆炸震源物理过程中最重要的非球对称源过程.对其机制的研究,多基于面波资料,本文基于远场体波资料,利用经验格林函数方法,消除路径及接收场地效应,利用地下核爆炸远场地震波P波数据对震源时间函数进行了反演,结果显示明显的双脉冲特征,该二次源特征不随方位角及震中距变化,说明它源自震源本身,其双脉冲特征与层裂机制相符.  相似文献   
999.
Multivariate storm frequency modeling would help to gain improved understanding of complex storm process, and provide useful information for regulating flooding risk. In this paper, the dependency...  相似文献   
1000.
A uniaxial concrete constitutive model considering the bond-slip effect is proposed and its finite element analysis (FEA) implementation on a fiber section  相似文献   
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