龙门山冲断带构造特征研究主要进展及存在问题探讨   总被引：25，自引：0，他引：25  

金文正  汤良杰  杨克明  万桂梅  吕志洲 《地质论评》2008,54(1):37-46

在前人研究成果基础上,对龙门山冲断带差异构造变形特征,构造几何样式,构造演化等几个方面进行了综述。研究表明,龙门山冲断带具有明显差异构造变形特征,即东西分带、南北分段、上下分层,同时发育大量构造变形样式,如断层相关褶皱、三角带、飞来峰、双重构造等等,在经历了多期复杂构造演化之后,构造变形样式具有多期叠加特征,最后提出详细地表构造地质建模、地震剖面精细解释及合理模型的建立,同时结合多种量化测试分析手段能够有效推进龙门山冲断带复杂构造样式与多期构造演化阶段分析研究工作,以及推动该地区的油气勘探。  相似文献   

试论柴达木盆地北缘构造样式与古、今层间氧化带的形成     

刘林 《铀矿地质》2008,24(1):12-16

柴达木盆地北缘是中新生代以来发育的块断带,中新生代盆地受逆冲推覆构造作用形成的构造岩席呈不同的展布形式.本文通过对不同构造部位构造样式的分析、中下侏罗统层间氧化带发育特征的阐述,认为在与盆地蚀源区相向的目的层,即对冲构造样式是古层间氧化带的发育部位,而相一致的单冲构造与斜坡带构造样式是现代层间氧化带发育的有利部位.  相似文献   

对南黄海盆地构造层特征及含油气性的新认识   总被引：8，自引：0，他引：8  

姚永坚  冯志强  郝天珧  徐行  李学杰  万荣胜 《地学前缘》2008,15(6)

南黄海是由古、中、新生界叠置而成的一个大型叠合盆地,发育4个特征各异的构造层:构造层Ⅰ(Z-S)、构造层Ⅱ(D-T)、构造层Ⅲ(T3-E)和构造层Ⅳ(N-Q)。构造层Ⅰ在海区广泛分布,主要为一套下古生界的盆地相-台地相沉积建造,最新地震资料推测,其厚度大且稳定,但构造特征不清楚。构造层Ⅱ由上古生界至中生界三叠系组成,是以碎屑岩和灰岩为主的一套海相地层,主要受到印支运动和早燕山运动的强烈影响,南、北部残留地层及结构不同,但以挤压构造样式为主。与陆区比较,南黄海盆地海相构造层Ⅰ和构造层Ⅱ的构造格局相对稳定,变形强度较弱。构造层Ⅲ发育白垩系和古近系,局部存在上三叠统—侏罗系,白垩系和古近系主要赋存在坳陷或凹陷内,隆起或凸起基本缺失,为一套陆相砂泥岩沉积,在北部坳陷分布较广,但厚度变化快,剖面上表现为地堑、半地堑的结构特征,以拉张构造样式为主。构造层Ⅳ(N-Q)为区域沉降的产物。南黄海盆地在形成过程中经历了多次构造运动的改造,不同构造单元具有不同的油气成藏特征和富集规律,北部坳陷发育有古生古储、古生新储、新生古储等油气成藏组合类型,是油气勘探最有利的区域。  相似文献   

砂岩储层孔隙保存的定量预测研究   总被引：52，自引：4，他引：48       下载免费PDF全文

寿建峰  朱国华 《地质科学》1998,33(2):244-250

对北方地区若干盆地的砂岩孔隙发育特征的研究表明,地温场、地质年代和盆地沉降方式对砂岩孔隙的演化和保存有制约作用。地温梯度每增加1℃,砂岩孔隙度平均减小约7%;在地温梯度2-4℃/100m范围内,有效储层的保存深度差异可达2500-3000m.地质年代每增加1Ma,砂岩孔隙度降低约0.018%-0.009%.地层超压可最大保存5%-7%的孔隙度。盆地沉降方式不同引起的孔隙保存量的差异为2%-5%,相应的有效孔隙保存深度的差值约1000m。  相似文献   

油气成藏系统──概念、分类和应用   总被引：4，自引：0，他引：4  

辛仁臣 《地球科学进展》1997,12(3):265-269

介绍了油气成藏系统的有关概念、成因分类及其在勘探中的应用。油气成藏系统将油气藏形成的各种地质因素、过程及其历史作为一个有机联系的系统进行整体研究。成熟烃源岩的质量、数量和油气显示情况是油气成藏系统分析中的两个重要方面。在一个油气成藏系统中，三个关键因素是源岩充注能力、烃类运移方式和捕集方式，它们构成油气成藏系统成因分类的依据。油气成藏系统理论是油气远景评价工作十分有效的工具，已成功地应用于生产实践中。油气成藏系统理论已成为近年来石油地质学领域的热点之一。  相似文献   

Structure Styles of Mesozoic-Cenozoic U-bearing Rock Series in Northern China   总被引：1，自引：0，他引：1  

JIN Ruoshi  MIAO Peisen  SIMA Xianzhang  LI Jianguo  ZHAO Hualei  ZHAO Fengqing  FEN Xiaoxi  CHEN Yin  CHEN Lulu  ZHAO Lijun  ZHU Qiang 《《地质学报》英文版》2016,90(6):2104-2116

In Northern China, sandstone-type uranium (U) deposits are mostly developed in Mesozoic-Cenozoic basins. These U deposits are usually hosted in unvarying horizons within the basins and exhibit typical U-forming sedimentary associations, which is referred to as U-bearing rock series. This study describes the structural features of U-bearing rock series within the main Mesozoic-Cenozoic U-producing continental basins in Kazakhstan, Uzbekistan, and Russia in the western segment of the Central Asian Metallogenic Belt (CAMB), and Northern China in the eastern segment of the CAMB. We analyze the basic structural conditions and sedimentary environments of U-bearing rock series in Northern China and classify their structural styles in typical basins into river valley, basin margin, and intrabasin uplift margin types. The intrabasin uplift margin structural style proposed in this study can be used to indicate directions for the exploration of sandstone-type U deposits hosted in the center of a basin. At the same time, the study of structural style provides a new idea for exploring sandstone-type U deposits in Mesozoic-Cenozoic basins and it is of great significance to prospecting of sandstone-type uranium deposits.  相似文献   

泥石流源地土抗剪强度指标φ、C值同含水量Q的关系     

刘雷激  朱平一  张军 《山地学报》1998,(2)

源地上抗剪强度指标φ、C值对泥石流的发生具有重要意义,为探索源地上抗剪强度与主体含水量关系而做的主体φ、C值随含水量变化的试验表明,在源地土含水量达到塑限以前,φ值随含水量的变化不是线性的,而是主要呈上凸和下凹两种曲线形式;C值随含水量的变化基本上是单调上升的.  相似文献   

A study of rupture length vs. moment for synthetic earthquakes     

Jeen-Hwa Wang 《Pure and Applied Geophysics》1995,144(2):211-228

From the events synthesized from the one-dimensional dynamical mass-spring model proposed byBurridge andKnopoff (1967), the relation between rupture length and earthquake momentM is studied for various model parameters. The earthquake moment is defined to be the total displacement of a connected set of mass elements which slide during an event. A parameter stiffness ratios is defined as the ratio of the spring constant between the two mass elements to that between one mass element and the moving plate. The velocity-dependent friction law (including weakening and hardening processes) is taken to control the sliding of a mass element. The distribution of the breaking strengths over the system is considered to be a fractal function. The cases for severals values and different velocity-dependent friction laws with different decreasing ratesr _w of the frictional force with sliding velocity are studied numerically. The weakening process of the frictional force from the static one to the dynamic one obviously affects theM– relation. Meanwhile, a rapid weakening process rather than a slow weakening process can result in aM– relation, which is comparable to the observed one. Although an increase in thes value can yield an increase in the upper bound of the value and the number of events with largeM and values, the scaling of theM– relation is not affected by the change of thes value. For the cases in this study, the theoretical –M relations for small events withM<1 are almost in the form: M ^1/2, while those for large events withM>1 have a scaling exponent less than but close to 1. In addition, the fractal dimension, the friction drop ratio and the roughness of the distribution of the breaking strengths over the fault surface are the minor parameters influencing the –M relation. A comparison between the theoreticalM– relation and the observed one for strike-slip earthquakes shows that for large events the theoreticalM– relation is quite consistent with the observed one, while for small events there is a one-order difference in the two relations. For the one-dimensional model, the decreasing rate of the dynamic frictional force with velocity is the main factor in affecting the characteristic value of the earthquake moment, at which the scaling of theM– relation changes.  相似文献   

不同时间尺度下农田土壤风蚀可蚀性的变化   总被引：1，自引：1，他引：0  

王仁德  安晨宇  苑依笑  张春来  李庆  查慧敏  常春平  郭中领 《中国沙漠》2021,41(5):202-209

土壤风蚀可蚀性（简称土壤可蚀性）作为风蚀模型的必要输入参数之一,会随风蚀事件过程、耕作措施以及气象气候等因素发生显著变化,但目前对其变化趋势尚认识不足。本文采用野外观测、采样分析与空间换时间的方法,就次风蚀事件、风蚀月、风蚀季、多年4个时间尺度下坝上地区农田土壤可蚀性变化问题进行研究。结果表明：严重风蚀事件过程中,地表土壤中粒径<0.85 mm干团聚体颗粒的含量明显降低,临界起沙摩阻风速明显升高,输沙率明显减弱,三者均显示土壤可蚀性出现明显降低的趋势。风蚀月、风蚀季和多年3个时间尺度下,农田特别是翻耕农田土壤可蚀性均呈下降的趋势,并且时间尺度越长,土壤可蚀性的下降幅度越大。强烈的风蚀搬运作用可能是造成各时间尺度下坝上地区农田土壤可蚀性普遍下降的主因。为了降低坝上地区农田风蚀的危害,应减少新农田的开垦并尽量避免在风蚀事件高发期进行农田翻耕。  相似文献   

渤海湾盆地车镇凹陷古近系构造样式对沉积及储集层的影响^*   总被引：3，自引：1，他引：2       下载免费PDF全文

路智勇 《古地理学报》2008,10(3):277-285

近年来,构造对沉积的控制作用研究成为当前国际地质和油气勘探研究中的一个热点,但构造对储集层质量影响的研究相对较缺乏。在对车镇凹陷构造、沉积、储集层研究的基础上,讨论了不同构造样式中沉积充填和储集层发育特征。构造样式对沉积充填类型及特征具有重要影响,其中板式构造样式区仅发育近岸水下扇及少量滑塌浊积扇;铲式构造样式区除在边界断裂根部附近发育近岸水下扇外,其前端湖底扇常较发育;断阶式和坡坪式构造样式区受次级断裂控制,陆上与水下沉积常常共生,沉积类型多样,从冲积扇、扇三角洲到近岸水下扇、湖底扇均可发育。构造样式通过影响砂砾岩体的垂向叠置方式、规模和沉积类型及砂体结构,最终影响了其储集层质量。综合研究认为,断阶式和坡坪式构造样式区沉积类型丰富,为有利储集层最发育区;铲式构造样式区湖底扇发育,砂砾岩单层薄,为次级有利区;而板式构造样式区砂砾岩展布窄、单层厚度大,储集层质量最差。该认识为中低勘探程度的含油气断陷盆地中优质储集层发育带的预测提供了思路。  相似文献