基于方位地震数据的地应力反演方法   总被引：1，自引：0，他引：1       下载免费PDF全文

马妮  印兴耀  孙成禹  宗兆云 《地球物理学报》2018,61(2):697-706

在页岩油气藏的开发和勘探阶段,需要对储层进行水力压裂改造,形成有利于油气聚集和运移的裂缝.地应力是进行水力压裂改造的重要参数,能够决定裂缝的大小、方向以及分布形态,影响着压裂的增产效果,且最大和最小水平应力差异比（ODHSR,Orthorhombic Differential Horizontal Stress Ratio）是评价储层是否可压裂成网的重要因子.本文探讨了基于地震数据估算地应力的方法,以指导页岩气的水力压裂开发.首先,利用叠前方位地震数据反演得到地层的弹性参数和各向异性参数;其次,基于正交各向异性水平应力差异比近似公式,利用反演得到的弹性参数和各向异性参数估算地层的ODHSR;最后,选取某工区的裂缝型页岩储层的叠前方位地震数据对该方法进行实际应用.实际工区地震数据应用表明,基于叠前方位地震数据反演得到的ODHSR能够有效的识别储层中易于压裂成网的区域.  相似文献   

黏土涂抹充填方法评价断层封闭性研究   总被引：2，自引：0，他引：2  

杨智  何生  李奇艳  王芙蓉 《世界地质》2005,24(3):259-264

断层封闭性的评价是研究控制油气运聚的断裂输导体系的核心问题.黏土涂抹充填评价方法是评价断层封闭性的方法之一.断层封闭与否的机理是断裂带及断层两盘存在排驱压力差,黏土涂抹充填方法将断裂带中的泥质百分含量与排驱压力差的相关关系很好地反映出来.列举影响断层封闭性的诸多要素,探讨因黏土涂抹充填封闭断层的机理,进而总结了国内外用黏土涂抹充填方法研究断层封闭性的进展,重点讨论了断层泥比率法（SGR）及与其相关的定量评价方法.  相似文献   

A novel combined spectral index for estimating the ratio of carotenoid to chlorophyll content to monitor crop physiological and phenological status     

《International Journal of Applied Earth Observation and Geoinformation》2019

Accurate estimation of the ratio of carotenoid (Car) to chlorophyll (Chl) content is crucial to provide valuable insight into diagnoses of plant physiological and phenological status in crop fields. Studies for assessing the ratio of Car to Chl content have been extensively conducted with semi-empirical approaches using spectral indices. However, spectral indices established in previous studies generally relied on site- or species-specific measured data and these indices typically lacked sufficient estimation accuracy for the ratio of Car to Chl content to be used across various species and under different physiological conditions. In this study, we propose a novel combined carotenoid/chlorophyll ratio index (CCRI) in the form of the carotenoid index (CARI) divided by the red-edge chlorophyll index (CI_red-edge): The value of the index is illustrated using synthetic data simulated from the leaf radiative transfer model PROSPECT-5 and with extensive measured datasets at both the leaf and canopy level from the ANGERS dataset and winter wheat and maize field experiments. Results show that CCRI was the index with the highest correlation with the ratio of Car to Chl content in PROSPECT-5 simulations (R² = 0.99, RRMSE = 8.65%) compared to other spectral indices. Calibration and validation results using the ANGERS and winter wheat leaf level data showed that CCRI achieved accurate estimation of the ratio of Car to Chl content (R² = 0.52, RRMSE = 14.10%). CCRI also showed a good performance (R² = 0.54, RRMSE = 17.08%) for estimation of the ratio of Car to Chl content in both calibration and validation with the winter wheat and maize canopy spectra measured in field experiments. Further investigation of the effect of the correlation between leaf Chl and Car content on the performance of CCRI indicated that variation of the correlation affected the retrieval accuracy of CCRI, and CCRI might not be very sensitive to changes of the ratio of Car to Chl content with low values (<0.10).  相似文献   

普朗含矿斑岩岩体岩相、稳定同位素特征     

徐伯恩  罗诚 《云南地质》2012,(2):171-176

赋矿的普朗含矿复式斑岩体,具典型斑状特征及铜、钼、铁成矿专属性,由边缘到中心具石英闪长玢岩→石英二长斑岩演化关系,硅化钾化、绢英岩化蚀变与铜矿关系密切,尤以石英二长斑岩蚀变和矿化作用最强烈。硫同位素表明岩体属幔-壳源硫特征,铅同位素显示岩体铅集中分布于造山带演化线附近及下地壳、造山带、岛弧重叠区的特征。  相似文献   

水平层状介质中基阶瑞利面波椭圆极化特征数值分析与研究   总被引：2，自引：1，他引：1       下载免费PDF全文

张立  刘争平 《地球物理学报》2013,56(5):1686-1695

近年来的工程实践表明,以速度频散特性为理论基础的传统瑞利面波法的实际应用存在场地限制的瓶颈问题.为克服该困难,本文从面波的基础理论着手,在前人建立的水平层状介质中瑞利面波速度频散方程的基础上,推导了水平层状介质中瑞利面波质点位移的解析解公式.以工程中常见的几种典型的水平层状地层模型为例,结合地脉动单点谱比法(HVSR,Horizontal to Vertical Spectral Ratio),对基阶瑞利面波的椭圆极化特征进行了数值模拟研究.研究结果表明:与瑞利面波的速度频散特性类似,其椭圆极化同样具有频散特性,且椭圆极化时的质点位移水平分量与垂直分量的频谱比与地层泊松比结构有关.瑞利面波的这种椭圆极化特性展示了利用单点瑞利面波的多分量评价地层泊松比结构的理论可行性.  相似文献   

基于可靠性指标的Ratio检验模糊度质量方法   总被引：1，自引：0，他引：1  

邓健  潘树国  赵兴旺 《测绘科学》2013,38(3):37-39

整周模糊度估值的可靠性对保障卫星导航定位精度有着至关重要作用,本文针对常规Ratio检验模糊度方法中阈值c难以确定问题,基于模糊度成功率检验理论分析了Ratio检验法的概率特性,推导了模糊度失败率与Ratio检验阈值间的函数关系式,实现利用给定可靠性指标——模糊度失败率确定Ratio检验阈值c,从而保证模糊度固定解的可靠性。算例表明,该方法可解决Ratio检验中阈值c动态取值的关键问题,具有一定的实际意义。  相似文献   

基于Landsat TM6的林区温度反演研究     

李更连  ;曾庆伟  ;武红敢 《测绘软科学研究》2009,(1):56-59

主要研究利用Landsat TM6热红外波段遥感数据定量反演林地温度的方法与可行性。首先计算了研究区的比值植被指数（RVI），然后利用单窗算法开展林地温度反演，建立起了林地温度与比值植被指数之间的相关关系。研究结果表明：利用单窗算法反演的林地温度精度较高；林地温度与比值植被指数（RVI）25间存在着密切的负相关关系，林地温度与林冠变化之间关系十分密切。  相似文献   

The Relationships of Sunspot Magnetic Field Strength with Sunspot Area, Umbral Area and Penumbra-Umbra Radius Ratio     

C. L. Jin  Z. Q. Qu  C. L. Xu  X. Y. Zhang  M. G. Sun 《Astrophysics and Space Science》2006,306(1-2):23-27

Stokes profile inversion is very important to get the information on the vector magnetic field. Because the magnetic fields cannot be directly observed, adopting Stokes spectrum analysis to obtain vector magnetic field has become the major technique recently. Therefore, by Stokes profile inversion, we obtained vector magnetic fields of two layers based on the numerical solution (DELO solution, ReEs et al., 1989) to the polarized radiative transfer equation. We analyze the relationships of sunspot magnetic field strength with sunspot area, umbral area and penumbra-umbra radius ratio. By statistical research, it is found that the field strengths of the upper layer and the lower one decrease with the increasing penumbra-umbra radius ratio, and that the logarithmic expression is able to fit well the relationship between the maximum field strength of the upper layer and the sunspot area. Furthermore, we verify the result obtained by Ringnes and Jensen (1961) about the relationship between the maximum magnetic field strength and the umbral area, and the result obtained by Antalová (1991) of the relationship between the field strength and the penumbra-umbra radius ratio.  相似文献   

行星变速箱传动比方案的计算机辅助设计     

李自新 《广东海洋大学学报》1994,(2)

传动比方案设计是行星变速箱ＣＡＤ技术中的关键问题之一。本文应用行星变速箱基本设计理论和计算机技术，建立了行星变速箱传动比方案ＣＡＤ软件，为有关科研部门及生产企业的产品开发提供了一种有效手段。  相似文献   

海床式静力触探在黄河口海底土工程特性研究中的应用          下载免费PDF全文

楚立鹏  孙永福  宋玉鹏  董立峰  周其坤  马彬彬  张伟朋 《海岸工程》2017,36(1)

海床式静力触探设备工作效率高,能够实现从垂向上对地层的连续探测,数据分辨率较好。通过对黄河口海域3个静力触探孔和1个地质钻孔的分析,将研究区20m以浅地层自上而下划分为粉土、粉质黏土、粉土夹粉砂或粉砂、粉质黏土、粉土五层,静力触探曲线对粉土层中的硬壳层和粉质黏土层中的贝壳夹层等特殊地质现象有很好的反映。对粉质黏土的静力触探参数与物理力学参数进行相关性分析,得到适合该区域的回归方程。采用基于CPT数据的液化判别法,对研究区表层粉土液化可能性进行评判,通过Seed简化法计算的周期应力比(CSR)与Olsen法计算的周期阻力比(CRR)的大小比较,得出当抗震设防烈度为7度时,研究区表层粉土不会液化,当抗震设防烈度为8度时,粉土层将发生液化,计算最大液化深度3.7m。  相似文献