Types, Evolution and Pool-Controlling Significance of Pool Fluid Sources in Superimposed Basins： A Case Study from Paleozoic and Mesozoic in South China   总被引：2，自引：0，他引：2  

徐思煌梅廉夫  袁彩萍马永生 郭彤楼 《中国地质大学学报(英文版)》2007,18(1):49-59

Having multiple tectonic evolution stages, South China belongs to a superimposed basin in nature. Most marine gas pools became secondary pools. The pool fluid sources serve as the principal pool-controlling factors. On the basis of eight typical petroleum pools, the type, evolution in time-space, and the controlling of petroleum distribution of pool fluid sources are comprehensively analyzed. The main types of pool fluid sources include hydrocarbon, generated primarily and secondly from source rocks, gas cracked from crude oil, gas dissolved in water, inorganic gas, and mixed gases. In terms of evolution, the primary hydrocarbon was predominant prior to Indosinian; during Indosinian to Yen- shanian the secondary gas includes gas cracked from crude oil, gas generated secondarily, gas dissolved in water, and inorganic gas dominated; during Yenshanian to Himalayan the most fluid sources were mixed gases. Controlled by pool fluid sources, the pools with mixed gas sources distributed mainly in Upper Yangtze block, especially Sichuan (四川) basin; the pools with primary hydrocarbon sources distributed in paleo-uplifts such as Jiangnan (江南), but most of these pools became fossil pools; the pools with secondary hydrocarbon source distributed in the areas covered by Cretaceous and Eogene in Middle-Lower Yangtze blocks, and Chuxiong (楚雄), Shiwandashan (十万大山), and Nanpanjiang (南盘江) basins; the pools with inorganic gas source mainly formed and distributed in tensional structure areas.  相似文献   

宁夏中部牛首山地区构造特征及其地质意义   总被引：2，自引：4，他引：2  

张进  马宗晋  任文军  雷永良 《大地构造与成矿学》2003,27(2):132-142

宁夏中部牛首山地区的古生代地层发育了许多具有逆冲构造特征的的变形构造,断层相关褶皱非常发育。通过分析这些构造及其相互关系,恢复了该地区中奥陶统米钵山组的变形过程,表明该套地层经历了(1)岩层受到水平挤压,顺层缩短阶段,(2)褶皱变形阶段,(3)逆冲变形阶段等三个阶段;这些构造是逆冲推覆构造发育不同阶段的产物。牛首山以及宁夏南部的大、小罗山是古逆冲构造带的前缘部分,宁夏中南部地区在中奥陶世至泥盆纪是作为北祁连造山带北侧的弧后前陆盆地靠大陆一侧而存在随着该弧后盆地的关闭,牛首山前缘构造带形成。而现今的牛首山以及宁夏中南部的奥陶系很可能都是无根的。  相似文献   

Fault-related folds and an imbricate thrust system on the northwestern margin of the northern Fossa Magna region, central Japan   总被引：1，自引：0，他引：1  

Yukinobu Okamura 《Island Arc》2003,12(1):61-73

Abstract   The Nishikubiki Mountains, which are located on the northwestern margin of the northern Fossa Magna region, central Japan, and the area offshore to the north of the mountains are underlain by folded and faulted Neogene and Quaternary sequences. The folds are composed of open, symmetric anticlines or tight, asymmetric anticlines trending north 20–70° east. On the basis of the geometry of the anticlines and growth strata, the symmetric and asymmetric anticlines are interpreted as fault-bend folds and fault-propagation folds, respectively. The formation of the anticlines is attributed to the growth of an imbricate thrust system composed of three thrust sheets that developed, from southeast to northwest, mainly in the late Pliocene, early Pleistocene, and middle Pleistocene–Holocene. The horizontal component of the northwestern-most sheet was estimated to be approximately 1.2 km on the basis of the width of the growth triangle, and the thickness of the sheet at its southeast margin was estimated to be 8.5 km on the basis of area balancing along one of the seismic profiles. The thrust is inferred to extend to a depth of more than 10 km toward the southwest. The three thrust sheets are probably connected by a detachment zone along the boundary between the upper and lower crusts. The anticlines are bounded by the Itoigawa–Shizuoka Tectonic Line (ISTL) to the west and by lateral ramps or tip lines to the northeast. The ISTL possibly continues northward offshore into the Toyama Trough. The structural model proposed in this paper suggests that similar thrust systems are wide spread in the northern Fossa Magna region and that active deformation zones have migrated and switched during the past 2–3 million years along the fold belt.  相似文献   

构造叠加晕法在预测金矿区深部盲矿中的应用效果   总被引：6，自引：5，他引：6  

李惠  张国义  王支农  张文华 《物探与化探》2003,27(6):438-440

在原生晕分带理论的基础上,根据不同成矿阶段的元素组合、不同成矿阶段矿体的轴向分带及其在空间上的叠加特点,建立起一种预测盲矿的新模式---构造叠加晕模式.构造叠加晕法在一些金矿区深部及其外围预测盲矿已取得了显着效果.  相似文献   

塔里木西北缘北西向古隆起的存在及油气勘探前景   总被引：8，自引：0，他引：8  

杨庚 《新疆地质》2003,21(2):157-162

塔里木西北缘柯坪逆冲带为天山和塔里木盆地在中新生代盆山耦合过程中形成，为印度板块和欧亚板块碰撞影响最显的地区之一．柯坪地区存在两种方向的构造，即NE向逆冲推覆构造和NW向的走滑构造及潜伏构造．在NE逆冲带的走向上，推覆构造变形样式从南向北，以寒武纪蒸发岩作为主要的滑动拆离面——薄皮逆冲，到北部地区卷入元古界结晶基底的逆冲推覆构造．根据变形时代分析，NW向构造为长期发育的巴楚隆起，形成时代为中生代早期，近NE向的柯坪逆冲构造形成于新生代，同时也形成NW向的走滑构造．早期形成的巴楚隆起构造南北两侧发育的阿瓦提盆地和塔里木盆地西南为生油区，巴楚隆起为油气运移指向区．  相似文献   

Strain determination from concentric folds     

Hari B. Srivastava 《Tectonophysics》2003,364(3-4):237-241

A new technique to determine flattening strain from initially concentric folds is described in this paper. The proposed method is simple and involves direct measurements on fold profiles. It requires measurement of the distance between the center of the fold to the middle of the layer, and this is plotted as a function of line orientation. The method needs few measurements at fixed angular spacing resulting in quick estimation of strain.  相似文献   

Paleozoic northward drift of the North Tien Shan (Central Asia) as revealed by Ordovician and Carboniferous paleomagnetism   总被引：7，自引：0，他引：7  

Mikhail L. Bazhenov  Adam Q. Collins  Kirill E. Degtyarev  Natalia M. Levashova  Alexander V. Mikolaichuk  Vladimir E. Pavlov  Rob Van der Voo   《Tectonophysics》2003,366(1-2):113-141

Three new Middle–Late Ordovician and two new Early Carboniferous paleomagnetic poles have been obtained from the North Tien Shan Zone (NTZ) of the Ural–Mongol belt in Kyrgyzstan and Kazakhstan. Paleolatitudes for the Carboniferous are unambiguously northerly and average 15.5°N, whereas the Ordovician paleolatitudes (6°, 9°, and 9°) are inferred to be southerly, given that a very large (180°) rotation of the NTZ would be necessary during the middle Paleozoic if the other polarity option was chosen. Thus, the NTZ drifted northward during much of the Paleozoic; east–west drift cannot be determined, as is well known, from paleomagnetic data. In addition, detailed thermal demagnetization analysis reveals two overprints, one of recent age and the other of Permian age, which is a time of strong deformation in the NTZ. The paleolatitude of the combined Permian overprint is 30.5+2°N. The paleolatitudes collectively track those predicted for the area by extrapolation from Baltica very well, but are different from those of Siberia for Ordovician times. This finding is compatible with Sengör and Natal'in's [Sengör, A.M.C., Natal'in, B.A., 1996. Paleotectonics of Asia: fragments of a synthesis. In: Yin A., Harrison, M. (Eds.), The Tectonic Evolution of Asia. Cambridge Univ. Press, Cambridge, pp. 486–640] model of tectonic evolution of the Ural–Mongol belt and disagrees with the models of other researchers. Declinations of the Ordovician and Early Carboniferous results range from northwesterly to northeasterly, and are clearly affected by local relative rotations, which seem characteristic for the entire NTZ, because the Permian overprint declinations also show such a spread. Apparently, the important latest Paleozoic–Triassic deformation involved shear zone-related rotations as well as folding and significant granitic intrusions.  相似文献   

The fold test as an analytical tool   总被引：1，自引：0，他引：1  

P. L. McFadden 《Geophysical Journal International》1998,135(2):329-338

Two fold tests for palaeomagnetism have recently been proposed that rely on the assumption that the total population of magnetic vectors is most highly concentrated with the rocks in the orientation they had at the time of acquisition of the magnetization. This leads to appealing, simple tests based on parameter estimation. However, it is shown that the underlying assumption is flawed and can lead to incorrect conclusions. McFadden & Jones (1981 ) previously developed an inference test based on the concept that the between-group dispersion of magnetization should be consistent with the within-group dispersion when the rocks are in the orientation they had at the time of magnetic acquisition. That test made unrealistic demands upon the sampling scheme for typical, realistic folding geometries and so it has been under-utilized. The McFadden & Jones test is extended by recognizing that it is sufficient to use groups with similar bedding corrections and that it is not necessary to insist on groups with common bedding corrections. These groups may easily be determined with a clustering algorithm. The point is that with the rocks in the orientation at which the magnetization was acquired, it should be immaterial how the groups are chosen.  相似文献   

沂沭断裂带活动褶皱及其与活动断层的关系   总被引：4，自引：0，他引：4  

晁洪太  李家灵  赵清玉  崔昭文 《地震研究》1998,(3)

利用１∶５万活断层地质填图获得的有关资料,初步讨论了沂沭断裂带活动褶皱的展布、内部结构以及与活动断层的关系。沂沭断裂带活动褶皱发育在Ｆ１、Ｆ２断层之间,呈串珠状伴随Ｆ５断层展布,开始形成于第三纪时期,主要形成于第四纪晚期,属活动褶皱。活动褶皱和活动断层是在右旋挤压剪切带中形成的两种构造形式。  相似文献   

古地磁多参考点方法及其在我国西部地体构造演化研究中的应用     

李朋武  董学斌  杨惠心 《吉林大学学报(地球科学版)》1998,(1)

构造倾斜会使原生剩磁偏角产生偏差,从而影响对地体构造旋转等特征的分析。对这种偏角偏差进行了理论分析和计算。倾伏褶皱在野外难以识别,即或识别,倾伏要素也很难准确测定。为此提出了利用多个参考点的古地磁资料分析地体运动特征的新方法。该方法是基于剩磁倾角数据,从而避免了偏角误差的影响,提高了分析的可靠性。利用该方法对我国西北地区的地质构造演化进行了研究,初步实现了该区古生代古地理的重建。  相似文献