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排序方式: 共有100条查询结果,搜索用时 31 毫秒
1.
Mustafa Y. Kaya Guillaume Dupont‐Nivet Jean‐Noël Proust Pierrick Roperch Laurie Bougeois Niels Meijer Joost Frieling Chiara Fioroni Sevin
zkan Altner Ezgi Vardar Natasha Barbolini Marius Stoica Jovid Aminov Mehmut Mamtimin Guo Zhaojie 《Basin Research》2019,31(3):461-486
The proto‐Paratethys Sea covered a vast area extending from the Mediterranean Tethys to the Tarim Basin in western China during Cretaceous and early Paleogene. Climate modelling and proxy studies suggest that Asian aridification has been governed by westerly moisture modulated by fluctuations of the proto‐Paratethys Sea. Transgressive and regressive episodes of the proto‐Paratethys Sea have been previously recognized but their timing, extent and depositional environments remain poorly constrained. This hampers understanding of their driving mechanisms (tectonic and/or eustatic) and their contribution to Asian aridification. Here, we present a new chronostratigraphic framework based on biostratigraphy and magnetostratigraphy as well as a detailed palaeoenvironmental analysis for the Paleogene proto‐Paratethys Sea incursions in the Tajik and Tarim basins. This enables us to identify the major drivers of marine fluctuations and their potential consequences on Asian aridification. A major regional restriction event, marked by the exceptionally thick (≤ 400 m) shelf evaporites is assigned a Danian‐Selandian age (ca. 63–59 Ma) in the Aertashi Formation. This is followed by the largest recorded proto‐Paratethys Sea incursion with a transgression estimated as early Thanetian (ca. 59–57 Ma) and a regression within the Ypresian (ca. 53–52 Ma), both within the Qimugen Formation. The transgression of the next incursion in the Kalatar and Wulagen formations is now constrained as early Lutetian (ca. 47–46 Ma), whereas its regression in the Bashibulake Formation is constrained as late Lutetian (ca. 41 Ma) and is associated with a drastic increase in both tectonic subsidence and basin infilling. The age of the final and least pronounced sea incursion restricted to the westernmost margin of the Tarim Basin is assigned as Bartonian–Priabonian (ca. 39.7–36.7 Ma). We interpret the long‐term westward retreat of the proto‐Paratethys Sea starting at ca. 41 Ma to be associated with far‐field tectonic effects of the Indo‐Asia collision and Pamir/Tibetan plateau uplift. Short‐term eustatic sea level transgressions are superimposed on this long‐term regression and seem coeval with the transgression events in the other northern Peri‐Tethyan sedimentary provinces for the 1st and 2nd sea incursions. However, the 3rd sea incursion is interpreted as related to tectonism. The transgressive and regressive intervals of the proto‐Paratethys Sea correlate well with the reported humid and arid phases, respectively in the Qaidam and Xining basins, thus demonstrating the role of the proto‐Paratethys Sea as an important moisture source for the Asian interior and its regression as a contributor to Asian aridification. 相似文献
2.
Late Jurassic-Early Cretaceous Northern Qaidam Basin, NW China: Implications for the earliest Cretaceous intracontinental tectonism 总被引:4,自引:0,他引:4
Lei Wu Ancheng Xiao Liqun WangZhongyan Shen Suping ZhouYuanzhong Chen Liang Wang Dong LiuJunya Guan 《Cretaceous Research》2011,32(4):552-564
Formation of Mesozoic western China, which was dominated by tectonic amalgamation along its southern margin and associated intracontinental tectonisms, holds a key for interpreting the succedent Cenozoic evolution. This paper presents new data including lithology, sedimentary facies, stratigraphic contact, seismic interpretation and paleo-structures within the Upper Jurassic-Lower Cretaceous strata in the northern Qaidam Basin, NW China. These data all account for a contractional tectonic deformation in the earliest Cretaceous. The South Qilian Shan, according to the sedimentary features and provenance analysis, reactivated and exhumated during the deformation, controlling the deposition of the Lower Cretaceous sequences. A simplified model for the Late Jurassic-Early Cretaceous paleogeography and tectonics of the northern Qaidam Basin is accordingly proposed. The results also support a ∼25° clockwise rotation of the Qaidam Basin since the Early Cretaceous and a more accurate Mesozoic evolution process for the basin. This earliest Cretaceous deformation, associated with the reactivation of the South Qilian Shan at the time, are part of the intracontinental tectonisms in central Asia during the Mesozoic, and probably driven by both the closure of the Mongol-Okhostk Ocean to the north and the collision of the Lhasa and the Qiangtang blocks to the south. 相似文献
3.
Chronostratigraphic constraints on Middle Pleistocene faunal assemblages and Acheulian industries from the Cretone lacustrine basin,central Italy 下载免费PDF全文
4.
燕山承德地区晚侏罗世盆地充填记录及对盆缘构造作用的指示 总被引:12,自引:2,他引:10
承德地区滦平—承德和大杖子—新城子晚侏罗世沉积盆地带分别与丰宁—隆化逆冲带和尚义—平泉逆冲带相邻。盆地充填的土城子组在垂向上可划分出三个主要由辫状河冲积平原及辫状河三角洲沉积体系组成的盆地相。沉积物岩屑和砾石成分统计表明 ,滦平—承德盆地北缘岩屑岩性相在垂向上表现出三个基底变质岩岩屑向上增多的旋回 ,而滦平—承德盆地南缘及大杖子—新城子盆地则由碳酸盐岩和碎屑岩岩屑表现出三个向上增多的旋回。盆地沉积学特征表明 ,滦平—承德盆地南北边缘分别受控于尚义—平泉北缘和丰宁—隆化逆冲带 ,而大杖子—新城子盆地受控于尚义—平泉南缘逆冲带。如果承德断层发生了长距离逆冲推覆活动 ,其活动时间绝非土城子组同沉积期和之后 ,应该发生于髫髻山组沉积之后和土城子组沉积之前。盆地中三个岩屑岩性相旋回和盆地相旋回共同地反映了盆缘逆冲带三次抬升剥露过程 相似文献
5.
6.
东海陆架前缘斜坡(冲绳海槽西坡)北部的断块隆脊地貌 总被引:1,自引:0,他引:1
东海陆架前缘斜坡(冲绳海槽西坡)北部的断块隆脊,是呈长条形的脊状台式隆起,位于29°30′N-31°10′N;128°00′E-128°20′E之间。其由NNE向链状排列的断块山地组成,且与NNE向的断裂构造相一致,其顶部水深约300m~400m左右。从实测单道地震剖面看,隆脊的东西两侧均有断层出现。隆脊西坡倾向陆架一侧,坡度大,有的地方坡度超过10°;而东侧坡度较缓,仅1°左右,缓倾至海槽西坡坡底,并以沟坎式与冲绳海槽槽底相连。冲绳海槽地区的构造运动,使隆脊地区受到断裂构造的作用。NNE向的大断裂使该隆脊位置的东西两侧断裂下降而中间抬起,加之下部岩浆上侵,显现出链式排列的断块山地,表现为一条长形的断块隆脊构造地貌体。推测该地貌体形成的时期较晚,它是与断层的发生同时期形成的。 相似文献
7.
RICARDO NÉSTOR MELCHOR 《Sedimentology》2007,54(6):1417-1446
Well‐exposed Triassic rift strata from the Ischigualasto–Villa Unión Basin (NW Argentina) include a 80 to ca 515 m thick lacustrine‐dominated package that can be correlated across a half‐graben using key stratigraphic surfaces (sequence boundaries, lacustrine flooding surfaces and forced regressive surfaces). The characteristics of the synrift lacustrine fill in different parts of the half‐graben have been examined and the mechanisms controlling sedimentation inferred. A variety of sedimentary environments are recognized including; volcaniclastic floodplain, mildly saline lake and playa lake, offshore lacustrine, delta front to fluvial‐dominated and wave‐dominated deltas, distributary and fluvial channel, and interdistributary bay. The succession can be divided into four stratigraphic sequences (SS1 to SS4), the oldest of which (SS1) contains volcaniclastic, fluvial and saline lake deposits; it is thickest close to the western border fault zone, reflecting more rapid subsidence here. Accommodation exceeded sediment and water input during SS1. The second and third sequences (SS2 and SS3) mark the onset of widespread lacustrine sedimentation, reflecting a balance between accommodation creation and water and sediment fluxes. Sequences SS2 and SS3 are represented by offshore meromictic lacustrine and deltaic deposits, the latter mostly sourced from the flexural and southern axial margins of the half‐graben. The presence of stacked parasequences bound by lacustrine flooding surfaces is related to climatically induced lake‐level fluctuations superimposed on variable rates of subsidence on the controlling rift border fault zone. The youngest sequence (SS4) is represented by the deposits of littoral lacustrine and shallow shelf deltas distinguished by a change in lithofacies, palaeocurrents and sandstone composition, suggesting a switch in sediment supply to the footwall margin to the NW. The change in the sediment source is related to reduced footwall uplift, the possible presence of a relay ramp and/or supply from a captured antecedent drainage network. During SS4, the rate of creation of accommodation was exceeded by the sediment and water discharge. The stratigraphic evolution of lacustrine strata in the half‐graben was mainly controlled by tectonic processes, including subsidence rate and the growth and evolution of the border fault zone, but changing climate (inducing changes in water balance and lake level) and autocyclic processes (delta lobe switching) were also important. 相似文献
8.
Rachna Raj 《Journal of Earth System Science》2007,116(5):413-421
The detailed analysis of landforms, drainages and geology of the area between the rivers Amaravati and Karjan was carried
out in order to understand the tectonic history of the lower Narmada basin. Movement along the various faults in the area
was studied on the basis of the drainage offsetting. Horizontal offsetting of stream channels was found quite demonstrable
along NNW-SSE trending transverse faults. Tectonic landforms including systematic deflection of stream channels and ridges,
alignment of fault scarp and saddles and displacement in the basement rocks and alluvial deposits show that the area is undergoing
active deformation driven by the NSF system. 相似文献
9.
10.
Sinkhole hazards along the eastern Dead Sea shoreline area, Jordan: a geological and geotechnical consideration 总被引:2,自引:0,他引:2
For the last four decades, the level of the Dead Sea has been subjected to continual variation which, among other important
factors, has led to the occurrence of much subsidence and many sinkholes in the southern Dead Sea area. Sinkhole activities
occurred repetitively and were observed in open farms, across roads, near dwellings and near an existing factory, thus causing
a serious threat to the locals and farmers of the area and their properties. This paper presents the main results from detailed
geological and geotechnical studies of this area. Aerial photo interpretation and borehole drilling aided these studies. Parallel
geophysical investigations (vertical electrical sounding and seismic refraction) and hydrological and hydrogeological studies
were made by others in the same area to also investigate this phenomenon. It was found that sinkholes are aligned to and follow
old water channels and are concentrated parallel to the recent shoreline of the Dead Sea. The development of subsurface cavities
is associated mainly with the variation in the level of the Dead Sea over the four past decades, the presence of regional
salt intrusion under the surface of salt beds, the fluctuation of the water table and continuous dissolution and the active
tectonism of the area. Moreover, this work showed that the area is still under active sinkhole hazards and other parts of
the area will be inevitably affected by sinkholes in the future.No practical engineering solution to this problem is feasible.
Received: 1 July 1999 / Accepted: 11 October 1999 相似文献