间歇侧移式的裂陷与递进跳跃式的反转：以阜新煤盆地为例   总被引：6，自引：0，他引：6  

王桂梁  马杏垣  荆惠林  云武  王大庆  谭海樵  李海玉 《高校地质学报》1996,(3)

位于闾山背斜隆起核部西侧的阜新断陷盆地从早白垩世义县组晚期开始，在东西两侧盆缘的Ｆ″１、Ｆ２断层所、围限的地堑内接受了义县组上部中性火山岩的堆积。火山喷发停止后，九佛堂组的大陆碎屑岩建造仍在Ｆ″１和Ｆ２断层之间的地堑内充填。九佛堂裂陷期之后该区地壳掀斜隆升，盆地南侧的义县地区开始反转抬升而不再接受沉积，西缘的Ｆ２断层也停止活动。到沙海组充填时盆地已演化为受Ｆ″１断层控制的、东断西超的半地堑盆地；沙海期裂陷终止后Ｆ″１断层停止活动，阜新组裂陷是在向东移的Ｆ′１盆缘断层控制下半地堑内发育的。阜新期裂陷结束后盆地又发生了一次跳跃式的反转，许多正断层发育成上逆下正的复合断层，并出现正花状构造。中白垩世孙家湾组的沉陷进一步向东侧移，形成了以Ｆ１断层为盆缘断层的半地堑；孙家湾期后发生本区最强烈的整体反转、隆升和褶断，结束了盆地的演化历史。阜新盆地间歇侧移式的裂陷与递进跳跃式的反转为盆地反转建立一个新的构造模式  相似文献   

关于岩浆型被动陆缘     

何国琦  李茂松 《城市地质》1996,(Z1)

在中国阿尔泰山南缘造山带的地质研究工作中发现，在这里存在一套有成生联系的花岗深成岩和火山岩系，它们不是板块汇聚阶段的产物，而是地壳拉张作用阶段的产物，它们形成于被动大陆边缘演化阶段。我们把这种大陆边缘称之为岩浆型波动陆缘，以便与无岩浆活动的大西洋型大陆边缘相区别。  相似文献   

Tectonometamorphic evolution of the Himalayan metamorphic core between the Annapurna and Dhaulagiri, central Nepal   总被引：12，自引：0，他引：12  

J.-C. VANNAY  & K. V. HODGES 《Journal of Metamorphic Geology》1996,14(5):635-656

The metamorphic core of the Himalaya in the Kali Gandaki valley of central Nepal corresponds to a 5-km-thick sequence of upper amphibolite facies metasedimentary rocks. This Greater Himalayan Sequence (GHS) thrusts over the greenschist to lower amphibolite facies Lesser Himalayan Sequence (LHS) along the Lower Miocene Main Central Thrust (MCT), and it is separated from the overlying low-grade Tethyan Zone (TZ) by the Annapurna Detachment. Structural, petrographic, geothermobarometric and thermochronological data demonstrate that two major tectonometamorphic events characterize the evolution of the GHS. The first (Eohimalayan) episode included prograde, kyanite-grade metamorphism, during which the GHS was buried at depths greater than c. 35 km. A nappe structure in the lowermost TZ suggests that the Eohimalayan phase was associated with underthrusting of the GHS below the TZ. A c. 37 Ma ⁴⁰Ar/³⁹Ar hornblende date indicates a Late Eocene age for this phase. The second (Neohimalayan) event corresponded to a retrograde phase of kyanite-grade recrystallization, related to thrust emplacement of the GHS on the LHS. Prograde mineral assemblages in the MCT zone equilibrated at average T =880 K (610 °C) and P =940 MPa (=35 km), probably close to peak of metamorphic conditions. Slightly higher in the GHS, final equilibration of retrograde assemblages occurred at average T =810 K (540 °C) and P=650 MPa (=24 km), indicating re-equilibration during exhumation controlled by thrusting along the MCT and extension along the Annapurna Detachment. These results suggest an earlier equilibration in the MCT zone compared with higher levels, as a consequence of a higher cooling rate in the basal part of the GHS during its thrusting on the colder LHS. The Annapurna Detachment is considered to be a Neohimalayan, synmetamorphic structure, representing extensional reactivation of the Eohimalayan thrust along which the GHS initially underthrust the TZ. Within the upper GHS, a metamorphic discontinuity across a mylonitic shear zone testifies to significant, late- to post-metamorphic, out-of-sequence thrusting. The entire GHS cooled homogeneously below 600–700 K (330–430 °C) between 15 and 13 Ma (Middle Miocene), suggesting a rapid tectonic exhumation by movement on late extensional structures at higher structural levels.  相似文献   

多电极直流探测系统及其应用效果   总被引：2，自引：0，他引：2  

李志武  周燕云  刘永东  贺宁波 《物探与化探》1996,20(6):461-470,473

本文介绍地质矿产部机电所研制的多电极直流探测系统的主要技术性能,硬件和软件设计特点,数据处理软件的配置以及在不同领域勘探应用实例。  相似文献   

泰和盆地构造和演化初探     

王迪文  龙天 《江西地质科技》1997,24(4):165-169

我国大部分地区的小新生代盆地的成生、演化受断裂构造的控制,泰和盆地即是严格受断裂构造控制的走滑拉张型盆地。本文着重从盆地的基底构造、盆缘断裂构造及盆地同生、后期构造阐述了它们与盆地形成和演化的关系。  相似文献   

Study of the liquefaction resistance of a saturated sand reinforced with Geosynthetics   总被引：1，自引：0，他引：1  

D. Vercueil  P. Billet  D. Cordary 《Soil Dynamics and Earthquake Engineering》1997,16(7-8):417-425

This article presents various tests using a cyclic triaxial instrument, on samples of saturated Hostun RF sand, reinforced with circular sheets of geosynthetic material. Tests performed with different types of geosynthetics of different compressibility, rigidity and roughness characteristics indicate a significant increase in liquefaction resistance for samples reinforced with compressible, non-woven geotextiles. The undrained behaviour of saturated Hostun RF sand reinforced with non-woven geotextiles is analysed on the basis of different test series. This analysis highlights the influence of reinforcement compressibility on interstitial pressure distribution in the sample, thus showing the role of this type of inclusion in the increase in liquefaction resistance.  相似文献   

北祁连加里东造山带从挤压到伸展造山机制的转换   总被引：1，自引：0，他引：1  

张建新  许志琴  李海兵  徐惠芬 《吉林大学学报(地球科学版)》1997,(3)

早古生代早期，北祁连造山带发生强烈的挤压变形作用，形成加里东期的俯冲－增生杂岩、高压变质岩，并使造山带岩石圈地壳加厚缩短。志留纪末期，加厚的造山带岩石圈由于垮塌作用及根部的拆沉作用，使造山带从挤压造山机制转换为伸展造山机制，并进入后造山伸展作用阶段，增厚的岩石圈开始减薄，发生不同层次的伸展作用，同时伴随花岗岩及Ａｎ∈变质岩的穹隆以及泥盆纪磨拉石盆地上叠盆地（Ｃ－Ｔ）的形成。石炭纪末，北祁连造山带岩石圈地壳已基本减薄到正常厚度。而现今的北祁连造山带的缩短和抬升则为喜马拉雅期再造山作用的产物  相似文献   

Tectonic Evolution of the Himalayan Collision Belt   总被引：5，自引：0，他引：5  

Cui Junwen Institute of Geology  Chinese Academy of Geological Sciences  Beijing 《《地质学报》英文版》1997,71(2):133-143

This paper discusses the tectonic divisions of the Himalayan collision belt anddeals with the tectonic evolution of the collision belt in the context of crustal accretion in thefront of the collision belt, deep diapirism and thermal-uplift extension and deep material flow-ing of the lithosphere-backflowing. Finally it proposes a model of the tectonic evolution-progressive intracontinental deformation model-of the Himalayan belt.  相似文献   

中国大陆科学钻探主孔2000米以上脆性变形构造应力场   总被引：6，自引：6，他引：6  

崔军文王连捷  李朋武徐东辉 吴海燕 《岩石学报》2004,20(1):73-80

在主孔2000米之内，存在复杂的脆性破裂系统和构造应力场。根据其充填物的特征，可划分为由石英、方解石和绿泥石等矿物充填的微破裂，发育石英、方解石等矿物薄膜或擦痕线理的微破裂和既无矿物充填、也无矿物薄膜的微破裂等3种不同类型的脆性应变现象，它们依次代表早、中、晚和深、中、浅3个不同构造层次的脆性变形。初步分析表明脆性变形阶段存在有以南东东-北西西向为主导的挤压作用、北东-南西向的区域挤压作用、南北向挤压作用和垂向伸展作用等4期构造应力场。郯庐断裂东侧的现代构造应力场在区域上具有极大的稳定性。在脆性和脆-韧性转换带，制约苏鲁高压-超高压变质带侵位的主导应力作用方式为自南东东往北西西方向的挤压，它在时间和空间上具有一定的稳定性。  相似文献   

辽西医巫闾山地区中生代两期韧性变形的研究   总被引：3，自引：0，他引：3  

张宏  王五力  李之彤  杨芳林  张立君  郑少林 《世界地质》2004,23(3):213-220

医巫闾山地区的韧性剪切构造是中生代两期韧性变形作用的产物。早期韧性变形中a线理发育,线理走向和糜棱面理走向基本一致,线理在xy面上的侧伏角绝大多数<30°;该期韧性变形是以左行走滑运动为主。晚期韧性变形中a线理发育,线理倾伏向和糜棱岩中糜棱面理倾向相近,线理在xy面上侧伏角主要在45°～90°之间;该期韧性变形是伸展作用的产物。医巫闾山中生代两期韧性剪切变形作用表明,在侏罗纪至早白垩世期间辽西地区不仅发生了强烈挤压推覆作用和伸展作用,也发生了大规模左行走滑作用。该韧性变形作用的发现对进一步研究辽西中生代的构造演化序列、期次和构造格架转换等问题有重要意义。  相似文献