CRETACEOUS AND TERTIARY BOUNDARY IN THE TINGRI REGION OF SOUTHERN TIBET     

Wan Xiaoqiao  Li Guobiao  A.Hallam    P.Wignall  WT  ”BX 《地学前缘》2000,(Z1)

CRETACEOUS AND TERTIARY BOUNDARY IN THE TINGRI REGION OF SOUTHERN TIBETtheNNSFProject(49872 0 0 3)andtheNationalProject (G19980 40 80 0 )ofChina  相似文献   

西藏第三纪有孔虫生物地层及地理环境   总被引：17，自引：2，他引：15  

万晓樵 《现代地质》1987,1(1):15

西藏南部海相第三系自下而上划分为:基堵拉组、宗浦组和遮普惹组。基堵拉组的归属直接关系到白垩——第三系的界线问题。以往在证据不充分的情况下将基堵拉组归于白垩系。本次工作在该组中找到了具时代意义的化石,有双壳类、介形虫、有孔虫等。通过化石群的研究确定了基堵拉组属于古新世丹宁早期。白垩—第三系界线应位于宗山组与基堵拉组之间。通过基堵拉组的横向对比得出了该组在空间上穿时的结论。浮游有孔虫动物群的发现确定了本区最高海相层为遮普惹组上段,时代属于始新世晚期。 西藏第三纪有孔虫类型丰富。据动物群的古生态研究得出了不同时代的有孔虫生物相:丹宁期为Rotalia生物相和Textularia生物相;朗德期为Miscellanea生物相和Ranikotbalia生物相;伊普尔期至路坦丁期包括Orbitolites生物相、Assilina生物相及冈底斯有孔虫生物相;普里亚波期以Globigerina生物相为特征。据有孔虫生物相的特征及氧碳稳定同位素的测试结果综合得出了西藏南部第三纪包括两次海侵旋回,即古新世和始新世旋回。二者又分别包括两回次一级的旋回,即古新世的丹宁期旋回和朗德期旋回;始新世的伊普尔期至路坦丁期旋回和普里亚波期旋回。  相似文献   

Stratigraphy and tectono-sedimentary evolution of the Upper Cretaceous–Tertiary sequence in the southern part of the Malatya Basin, East Anatolia, Turkey     

Mehmet nal  Meral Kaya 《Journal of Asian Earth Sciences》2007,29(5-6):878-890

The Malatya Basin is situated on the southern Taurus-Anatolian Platform. The southern part of the basin contains a sedimentary sequence which can be divided into four main units, each separated by an unconformity. From base to top, these are: (1) Permo-Carboniferous; (2) Upper Cretaceous–Lower Paleocene, (3) Middle-Upper Eocene and (4) Upper Miocene. The Upper Cretaceous–Tertiary sedimentary sequence resting on basement rocks is up to 700 m thick.The Permo-Carboniferous basement consist of dolomites and recrystallized limestones. The Upper Cretaceous–Lower Paleocene transgressive–regressive sequence shows a transition from terrestrial environments, via lagoonal to shallow-marine limestones to deep marine turbiditic sediments, followed upwards by shallow marine cherty limestones. The marine sediments contain planktic and benthic foraminifers indicating an upper Campanian, Maastrichtian and Danian age. The Middle-Upper Eocene is a transgressive–regressive sequence represented by terrestrial and lagoonal clastics, shallow-marine limestones and deep marine turbidites. The planktic and benthic foraminifers in the marine sediments indicate a Middle-Upper Eocene age. The upper Miocene sequence consists of a reddish-brown conglomerate–sandstone–mudstone alternation of alluvial and fluvial facies.During Late Cretaceous–Early Paleocene times, the Gündüzbey Group was deposited in the southern part of a fore-arc basin, simultaneously with volcanics belonging to the Yüksekova Group. During Middle-Late Eocene times, the Yeşilyurt Group was deposited in the northern part of the Maden Basin and the Helete volcanic arc. The Middle-Upper Eocene Malatya Basin was formed due to block faulting at the beginning of the Middle Eocene time. During the Late Paleocene–Early Eocene, and at the end of the Eocene, the study areas became continental due to the southward advance of nappe structures.The rock sequences in the southern part of the Malatya Basin may be divided into four tectonic units, from base to top: the lower allochthon, the upper allochthon, the parautochthon and autochthonous rock units.  相似文献   

Growing folds and sedimentation of the Gosau Group, Muttekopf, Northern Calcareous Alps, Austria     

Hugo Ortner 《International Journal of Earth Sciences》2001,90(3):727-739

Analysis of the three-dimensional geometry of Upper Cretaceous clastics in the Muttekopf area (Northern Calcareous Alps, Austria) indicate fold and fault structures active during deposition. Coniacian continental to neritic sedimentation (Lower Gosau Subgroup) was contemporaneous with displacements on NW-trending faults and minor folding along NE-trending axes. From the Santonian onwards (sedimentation of the deep-marine Upper Gosau Subgroup) the NW-trending faults were sealed and large folds with WSW-trending axes developed. The direction of contraction changed to N-S after the end of Gosau deposition in the Danian (Paleocene). Synorogenic sedimentation patterns indicate continuous contraction from the Coniacian to the Late Maastrichtian/?Danian. Therefore, large-scale extension as observed in the central part of the Eastern Alps cannot be documented in the western parts of the Northern Calcareous Alps. A combination of subduction tectonic erosion for the frontal parts and gravitational adjustment of an unstable orogen after nappe stacking for the internal parts possibly accounts for the different development of Gosau basins in the frontal and trailing regions of the Austroalpine wedge.  相似文献   

Meso-Cenozoic geodynamic evolution of the Paris Basin: 3D stratigraphic constraints     

《Geodinamica Acta》2000,13(4):189-245

3D stratigraphic geometries of the intracratonic Meso-Cenozoic Paris Basin were obtained by sequence stratigraphic correlations of around 1 100 wells (well-logs). The basin records the major tectonic events of the western part of the Eurasian Plate, i.e. opening and closure of the Tethys and opening of the Atlantic. From earlier Triassic to Late Jurassic, the Paris Basin was a broad subsiding area in an extensional framework, with a larger size than the present-day basin. During the Aalenian time, the subsidence pattern changes drastically (early stage of the central Atlantic opening). Further steps of the opening of the Ligurian Tethys (base Hettangian, late Pliensbachian;...) and its evolution into an oceanic domain (passive margin, Callovian) are equally recorded in the tectono-sedimentary history. The Lower Cretaceous was characterized by NE–SW compressive medium wavelength unconformities (late Cimmerian–Jurassic/Cretaceous boundary and intra-Berriasian and late Aptian unconformities) coeval with opening of the Bay of Biscay. These unconformities are contemporaneous with a major decrease of the subsidence rate. After an extensional period of subsidence (Albian to Turonian), NE–SW compression started in late Turonian time with major folding during the Late Cretaceous. The Tertiary was a period of very low subsidence in a compressional framework. The second folding stage occurred from the Lutetian to the Lower Oligocene (N–S compression) partly coeval with the E–W extension of the Oligocene rifts. Further compression occurred in the early Burdigalian and the Late Miocene in response to NE–SW shortening. Overall uplift occurred, with erosion, around the Lower/Middle Pleistocene boundary.  相似文献   

Sedimentological and stratigraphic evolution of northern Lebanon since the Late Cretaceous: implications for the Levant margin and basin     

Nicolas Hawie  Remy Deschamps  Fadi H. Nader  Christian Gorini  Carla Müller  Delphine Desmares  Ahmed Hoteit  Didier Granjeon  Lucien Montadert  François Baudin 《Arabian Journal of Geosciences》2014,7(4):1323-1349

This paper presents an updated review of the Upper Mesozoic and Cenozoic sedimentological and stratigraphic evolution of the Levant margin with a focus on the northern Lebanon. Facies and microfacies analysis of outcrop sections and onshore well cores (i.e., Kousba and Chekka) supported by nannofossil and planktonic foraminifers biostratigraphy, allowed to constrain the depositional environments prevailing in the Turonian to Late Miocene. The “Senonian” (a historical term used to define the Coniacian to Maastrichtian) source rock interval was subdivided into four sub-units with related outer-shelfal facies: (1) Upper Santonian, (2) Lower, (3) Upper Campanian, and (4) Lower Maastrichtian. This Upper Cretaceous rock unit marks the major drowning of the former Turonian rudist platform. This paper confirms the Late Lutetian to Late Burdigalian hiatus, which appears to be a direct consequence of major geodynamic events affecting the Levant region (i.e., the continued collision of Afro-Arabia with Eurasia), potentially enhanced by regressional cycles (e.g., Rupelian lowstand). The distribution of Late Burdigalian–Serravallian rhodalgal banks identified in northern Lebanon was controlled by pre-existing structures inherited from the pulsating onshore deformation. Reef barriers facies occur around the Qalhat anticline, separating an eastern, restricted back-reef setting from a western, coastal to open marine one. The acme of Mount Lebanon’s uplift and exposure is dated back to the Middle–Late Miocene; it led to important erosion of carbonates that were subsequently deposited in paleo-topographic lows. The Late Cretaceous to Cenozoic facies variations and hiatuses show that the northern Lebanon was in a higher structural position compared to the south since at least the Late Cretaceous.  相似文献   

Relative sea-level, tectono-eustasy, geoidal-eustasy and geodynamics during the Cretaceous     

N. -A. Mrner 《Cretaceous Research》1980,1(4):329-340

A priori, the recorded relative sea-level changes during the Cretaceous must be the combined effect of tectono-eustasy, geoidal-eustasy and various crustal level changes. To this we must add the human factor of differences and errors in interpretations.A posteriori, it is claimed that geoidal-eustasy dominated during the Hauterivian, Barremian, Turonian, Santonian and Maastrichtian, that tectono-eustasy dominated during the Albian, Cenomanian, Campanian and at the Maastrichtian/Danian boundary, and that local influences of sea-floor spreading are identified from the Albian/Cenomanian boundary onwards. To this we must add the local differential crustal movements modulating the global and regional ocean level changes. Geoidal-eustasy is mainly expressed as a latitudinal differentiation of the sea-level with out-of-phase changes between the hemispheres or the both high latitude regions. Furthermore, sedimentological records seem to record short-period geoidal-eustatic cycles.  相似文献   

Late Cretaceous ophiolite obduction and Paleocene India-Asia collision in the westernmost Himalaya     

Richard A. Beck  Douglas W. Burbank  William J. Sercombe  Asrar M. Khan  Robert D. Lawrence 《Geodinamica Acta》2013,26(2-3):114-144

Abstract

Collision of the Kohistan island arc with Asia at ~100 Ma resulted in N-S compression within the Neo-Tethys at a spreading center north of the Indo-Pakistani craton. Subsequent India-Asia convergence converted the Neo-Tethyan spreading center into a short-lived subduction zone. The hanging wall of the subduction zone became the Waziristan, Khost and Jalalabad igneous complexes. During the Santonian- Campanian (late Cretaceous), thrusting of the NW IndoPakistani craton beneath Albian oceanic crust and a Cenomanian volcano-sedimentary complex, generated an ophiolite-radiolarite belt. Ophiolite obduction resulted in tectonic loading and flexural subsidence of the NW Indian margin and sub-CCD deposition of shelf-derived olistostromes and turbidites in the foredeep. Campanian-Maastriehtian calci- clastic and siliciclastic sediment gravity flows derived from both margins filled the foredeep as a huge allochthon of Triassic-Jurassic rise and slope strata was thrust ahead of the ophiolites onto the Indo-Pakistani craton. Shallow to intermediate marine strata covered the foredeep during the late Maastrichtian. As ophiolite obduction neared completion during the Maastrichtian, the majority of India-Asia convergence was accommodated along the southern margin of Asia. During the Paleocene, India was thrust beneath a second allochthon that included open marine middle Maastrichtian colored mélange which represents the Asian Makran-Indus-Tsangpo accretionary prism. Latérites that formed on the eroded ophiolites and structurally higher colored mélange during the Paleocene wei’e unconformably overlapped by upper Paleocene and Middle Eocene shallow marine limestone and shale that delineate distinct episodes of Paleocene collisional and Early Eocene post-collisional deformation.  相似文献   

藏南定日剖面晚白垩世菊石和叠瓦蛤类的首次发现:生物地层和古环境意义(英文)     

JensLEHMANN InesWENDLER JensWENDLER HelmutWILLEMS XiumianHU 《地学前缘》2005,12(2):105-112

藏南定日遮普惹山剖面主要是Albian 晚期到古近纪海相沉积, Willems 等( 1996 )对岩石地层和沉积微相进行了详细研究,并通过浮游有孔虫研究建立生物地层格架。在与岗巴地区地层对比基础上,该剖面被认为是整个藏南地区白垩纪—古近纪海相地层的标准剖面。2004 年我们与中国、德国同行一道对该剖面上白垩统地层进行再考察,重点对无脊椎动物化石样品进行采集和研究。与西藏大多数白垩纪剖面一样,尽管沉积环境为陆棚环境,该剖面以前却几乎没有菊石和叠瓦蛤类化石的报道,而同样环境下的世界其他地区剖面含有大量的菊石和叠瓦蛤类化石。藏南定日剖面重新调查后发现了少量的菊石和叠瓦蛤类化石。化石数量少一方面是由于灰泥质灰岩和泥灰质灰岩内化石保存状况差,另一方面采样条件也不理想。还有,当时的环境条件可能不利于大多数无脊椎动物类群的生存,这一点或许从大量存在于岗巴群上部的小个体双壳类碎片可以得到证实。尽管获得的化石分散并且保存差,本次研究仍获得了一些有价值的生物地层数据。岗巴群上部发现的化石Calycoceras?,指示其时代为Cenomanian 晚期,随后出现不能鉴定的desmoceratids类的幼体。之上,菊石Forresteria sp.的发现表明岗巴群顶部地层属于Coniacian下部,这被同一地层内发现的其他化石所支?  相似文献   

转换大陆边缘盆地深水浊积砂岩油气成藏差异性研究     

孔令武  赵红岩  梁建设  程涛  王嘉  赵佳奇  喻英梅 《沉积学报》2022,40(1):244-254

深水浊积砂岩油气藏是当今世界油气勘探的热点领域。基于地震、钻井、地球化学等资料,系统分析了西非北段科特迪瓦盆地深水浊积砂岩油气成藏的差异性。研究表明,科特迪瓦盆地经历了裂陷期（早白垩世）和漂移期（晚白垩世—现今）两大构造演化阶段,漂移期发育塞诺曼—土伦阶优质海相烃源岩,裂陷期发育阿普特—阿尔布阶湖相烃源岩。漂移期层系为盆地的主力勘探层系,发育两种类型的浊积砂岩油气藏。塞诺曼—土伦阶浊积砂岩油气藏为典型的“砂体运移、自生自储、源内成藏”的油气成藏模式,其油气主要来源于塞诺曼—土伦阶烃源岩,广泛分布的浊积砂岩是油气运移的主要路径,烃源岩的生、排烃期决定了油气成藏时期,是否发育有效烃源岩是该类油气藏成藏的主控因素。圣通—马斯特里赫特阶浊积砂岩油气藏为典型的“断裂运移、下生上储、源外成藏”的油气成藏模式,其油气主要来源于深部裂陷期阿普特—阿尔布阶湖相烃源岩,断裂是油气运移的主要路径,断裂的活动控制了油气的运移和成藏时期,是否发育油源断裂是该类油气藏成藏的主控因素。  相似文献