建场测深法在新疆布尔津盆地油铀勘探中的应用     

白诗筠 《地质与勘探》2023,59(5):1054-1064

为明确位于新疆北部的布尔津盆地的资源状况,以实际采集数据为基础,采用建场测深法成果剖面研究了该盆地的地层地质结构,并对深层油气及浅部砂岩型铀矿进行评价。通过利用已知测井电阻率曲线模拟计算不同深度的电磁信号频率响应,论证了该方法探测从浅层第三系到深部石炭系的采集参数和工作方案;在数据处理成果的基础上,结合研究区已知地层物性特征,推断沿线的地质结构,揭示了布尔津凹陷的结构及下二叠统卡拉岗组、上石炭统哈尔加乌组、上石炭统恰其海组地层的分布,认为哈尔加乌组是本区有潜力的烃源岩。同时利用电阻率及双频相位属性对研究区浅部第三系砂岩型铀成矿条件进行分析,其结果与附近已知矿点情况吻合。本文提出的方法可为类似地区进行多种矿产资源勘探提供技术参考。  相似文献   

板钉连接CFST柱-RC梁节点梁端塑性铰区受力性能数值模拟     

马华  阚吉平  赵玉坤  李振宝 《震灾防御技术》2022,17(2):381-391

建立竖板-栓钉连接钢管混凝土（CFST）柱-钢筋混凝土（RC）梁节点试件（SSJD）拟静力加载试验有限元模型,并在节点损伤情况、梁端荷载-位移曲线等数值模拟结果与试验结果吻合较好的基础上,进一步开展了RC梁混凝土强度、配筋率ρ_s和连接竖板长度L_b及界面连接情况等对CFST柱-RC梁节点梁端塑性铰区域力学性能的影响。研究结果表明,RC梁混凝土强度对试件SSJD塑性铰区域受力性能的影响较小;适筋范围内RC梁配筋率增加可适当提高试件SSJD承载力和延性;随着连接竖板长度的增加,梁端塑性铰区域外移,梁破坏荷载增大;本研究给出的RC梁与CFST柱之间的界面抗剪承载力模拟值与计算值吻合较好,可用于界面抗剪设计。  相似文献   

Paleostress Reconstruction of Micangshan Anticlinorium on the Southern Margin of the Qinling Orogenic Belts, China     

LI Jinxi  LI Zhiwu  LIU Shugen  SUN Dong  DENG Bin 《《地质学报》英文版》2015,89(2):505-518

Brittle structures in rock of different ages can be used to establish the tectonic evolution of an orogenic belt through paleostress calculations. Micangshan is located at the southern margin of the Qinling orogenic belt,between the SE-trending Longmenshan fold-and-thrust belt and the arcuate Dabashan thrust-and-fold belt. Structural observations revealed that the dominant structures are reverse and strike-slip faults and folds with E–W and NE–SE trends. To increase knowledge of the tectonic evolution of the Micangshan anticlinorium,faults,joints,veins,and folds were measured at more than eighty sites. On the basis of structural analysis,it emerged that the multiphase paleostress fields became established after the oblique collision between the North and South China plates. The earliest stress field with N–S compression was established during the Micangshan uplift associated with the E–W trending faults and folds. Subsequently,a N–S extension occurred when the Qinling orogenic belt collapsed. Then NW–SE compression developed,with NE trending faults and folds forming in relation to Longmenshan thrusting toward southwest on the eastern margin of the Tibetan plateau. With the development of the arcuate Dabashan orogenic belt,the compression stress orientation of the Micangshan anticlinorium altered from NE–SW to E–W.  相似文献   

Improved Geometric Model of Extensional Fault–bend Folding     

ZHENG Xiaoli  HE Guangyu  HU Senqing  YAO Zewei  WANG Hui  LIN Lu 《《地质学报》英文版》2015,89(6):1847-1857

Extensional fault–bend folds, also called rollovers, are one of the most common structures in extensional settings. Numerous studies have shown that oblique simple shear is the most appropriate mechanism for quantitative modeling of geometric relations between normal faults and the strata in their hanging walls. However, the oblique simple shear has a rather serious issue derived from the shear direction, particularly above convex bends. We use geometric and experimental methods to study the deformation of extensional fault–bend folds on convex bends. The results indicate that whether the fault bends are concave or convex, the shear direction of the hanging wall dips toward the main fault. On this basis, we improve the previous geometric model by changing the shear direction above the convex bends. To illustrate basin history, our model highlights the importance of the outer limit of folding instead of the growth axial. Moreover, we propose a new expression for the expansion index that is applicable to the condition of no deposition on the footwall. This model is validated by modeling a natural structure of the East China Sea Basin.  相似文献   

节理型黄土开挖边坡塌滑破坏机理     

连宝琴  王新刚 《煤田地质与勘探》2015,(1)

黄土节理控制着黄土区地下水或者地表水的运输通道,黄土节理的发育致使黄土节理扩张为局部大的拉张裂隙,在拉张力作用下使得黄土高原地区塌滑灾害频繁发生。通过野外调查和分析,提出了黄土开挖边坡塌滑破坏可分为4个阶段:坡脚侵蚀剥落阶段、坡顶拉裂阶段、垂直裂隙扩展阶段、边坡整体塌滑破坏阶段。结合工程实例,通过概化的三维数值分析模型,使用岩土工程软件FLAC3D模拟分析了在3种降雨量条件(40 mm/d、80 mm/d、100 mm/d)下,降雨2 d后概化模型的塌滑破坏情况,这可为工程地质条件相同地区的黄土开挖边坡塌滑变形破坏的分析以及防治提供一种有效分析范例。  相似文献   

3维场景植被冠层多波段模拟研究进展     

张阳  柳钦火  覃文汉  刘强  李静  杜永明  谢东辉  黄华国  杨乐  倪文俭 《遥感学报》2015,19(6):894-909

植被冠层辐射散射信号中蕴含了丰富的植被信息,通过构建植被冠层辐射散射模型,可以实现植被结构等生物物理参数的遥感定量反演。迄今为止,可见光/近红外、热红外、微波波段均已发展了大量的模型,这些模型在参数反演方面各具优势,但不同波段的模型又有其自身的局限性。跨波段的联合模拟可以实现模型间的优势互补,进而提高地表参数的反演精度,近年来已有学者专注于可见光/近红外与热红外模型,热红外与微波模型,主被动微波模型,以及可见光/近红外与微波模型的联合模拟和协同反演,但多是两两联合,且主要是基于经验模型或解析模型。基于3维场景的植被冠层辐射散射特性模拟模型可以细致刻画不同组分的结构和空间分布特征,对于由植被结构引起的多次散射和组分比例变化的考虑具有优势。本文主要介绍了3维模拟模型在可见光/近红外、热红外和微波波段,以及跨波段联合模拟方面的研究进展,从模型机理、场景统一、以及组分理化参数的统一的角度,探讨了构建多波段3维模拟系统的可行性,展望了多波段3维模拟模型的发展趋势。  相似文献   

矢量地图数据数字水印抗拼接算法     

杨辉  闵连权  侯翔 《测绘科学技术学报》2015,(1):91-95

地图拼接是矢量地图数据中的一种常见处理方式。为了正确提取水印信息,需要从拼接后的地图中确定出水印嵌入区域。利用水印嵌入后坐标点尾部数据分布发生变化的特点,提出了一种基于分布拟合检验的抗拼接算法。该算法利用四叉树算法将地图分成多个区域,然后利用单样本K-S检验判断每个区域内的坐标点尾部数据是否服从均匀分布,最终确定出水印嵌入区域。实验表明,该算法能够达到提取水印嵌入区域的目的。  相似文献   

A bivariate gamma distribution for use in multivariate flood frequency analysis     

Sheng Yue 《水文研究》2001,15(6):1033-1045

A gamma distribution is one of the most frequently selected distribution types for hydrological frequency analysis. The bivariate gamma distribution with gamma marginals may be useful for analysing multivariate hydrological events. This study investigates the applicability of a bivariate gamma model with five parameters for describing the joint probability behavior of multivariate flood events. The parameters are proposed to be estimated from the marginal distributions by the method of moments. The joint distribution, the conditional distribution, and the associated return periods are derived from marginals. The usefulness of the model is demonstrated by representing the joint probabilistic behaviour between correlated flood peak and flood volume and between correlated flood volume and flood duration in the Madawask River basin in the province of Quebec, Canada. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

论多种数据联合反演的模式及算法   总被引：9，自引：3，他引：6  

李爽  许才军  王新洲 《大地测量与地球动力学》2002,22(3):78-82

针对日益丰富的数据资料，综述了大地测量反演的发展进程，论述了多种数据联合反演的意义和必要性，给出了兼顾权比确定的大地测量、地震和地质三类数据的联合反演模式及采用水准测量、GPS和重力三种数据联合反演断层参数的具体公式，特别介绍了求解优化问题所有全局最优解的区间算法，并给出了基本算例，结果体现了区间算法无可比拟的优越性及其在大地测量反演领域中的应用前景。  相似文献   

The key‐group method     

A. R. Yarahmadi Bafghi  T. Verdel 《国际地质力学数值与分析法杂志》2003,27(6):495-511

This paper proposes an extension to the key‐block method, called ‘key‐group method’, that considers not only individual key blocks but also groups of collapsable blocks into an iterative and progressive analysis of the stability of discontinuous rock slopes. The basics of the key‐block method are recalled herein and then used to prove how key groups can be identified. We reveal that a key group must contain at least one basic key block, yet this condition is not entirely sufficient. The second block candidate for grouping must be another key block or a block whose movement‐preventing faces are common to one or more single key blocks. We also show that the proposed method yields more realistic results than the basic key‐block method and a comparison with results obtained using a distinct element analysis demonstrates the ability of this new method. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献