Late Mesozoic compressional folds in Dongsha Waters, the northern margin of the South China Sea
Late Mesozoic compressional folds in Dongsha Waters, the northern margin of the South China Sea
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南海北缘东沙海域晚中生代挤压褶皱
DOI：
10.1016/j.tecto.2014.01.009
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发表时间：
2014-03
期刊：
影响因子：
2.9
通讯作者：
王彦林
中科院分区：
文献类型：
--
作者：
阎贫;王嘹亮;王彦林
东沙沃茨曾被认为是珠江口新生代盆地的组成部分，具有明显的构造-地层特征，其上部构造层仅为中中新世-第四纪的薄层沉积物（通常为0.5-1 km），而下部构造层由早白垩世陆相、侏罗纪海相和可能的三叠纪沉积岩组成，总厚度为4-9 km。它们之间的主要沉积间断期对应于晚白垩世至中新世中期，处于大陆裂谷-大洋扩张阶段。东沙沃茨中部地壳厚度多在25 km左右，南海开裂期的断裂和岩浆活动基本较弱，反映了一个相对稳定的块体。这表明新生代裂陷作用的影响较小，与邻区厚层的裂陷-漂积沉积形成鲜明对比。通过对东沙沃茨中生代地层的认识，提出东沙海域存在一个中生代残余盆地，并将其命名为东沙盆地，该盆地经历了晚第三纪和晚侏罗世-早白垩世两个世代的挤压作用，分别以海底和盲褶皱为特征。前者仅在东沙岛以东的少数地区出现。后者在北方以个体形式广泛分布，在南方以列群形式广泛分布。它们的特征主要是平缓的生长褶皱，褶皱内部只有少数较小的逆冲断层，偏移量为几十到几百米。逆冲断层大多向东南倾伏，逆着古太平洋向西北俯冲的方向倾伏。它们更像是逆冲生长构造，形成了一条斜向南海北方边缘的广泛的NNE-SSW向带，因此推测是晚中生代原太平洋俯冲的远场影响。
Once considered as a component part of the Cenozoic Pearl River Mouth Basin (PRMB), Dongsha Waters was found with distinct tectono-stratigraphic style, in which the upper structural layer comprises only thin (usually 0.5–1 km) sediments of mid-Miocene to Quaternary, whereas the lower layer consists of Early Cretaceous terrestrial, Jurassic marine and possibly Triassic sedimentary rocks, totaled 4–9 km thick. The major sedimentary hiatus between them corresponds to the Late Cretaceous to mid-Miocene Epoch, well during the continental rifting to oceanic spreading stage. Faulting and magmatism during the opening of the South China Sea are basically weak over the central part of Dongsha Waters where the crustal thickness is mostly around 25 km thick, reflecting a relatively stable block. All these indicate less influence exerted by the Cenozoic rifting, strikingly contrasting to the neighboring areas where thick rift-to-drift sediments have accumulated. With the recognition of Mesozoic strata in this and the previous study, a relict Mesozoic basin is proposed to be existed over Dongsha Waters and named as Dongsha Basin.There are two generations, Late Neogene and Late Jurassic to Early Cretaceous, of compressions featuring seafloor and blind folds, respectively. The former presents only in few localities in east to Dongsha Island. The later distributes widely as individuals in north and as trains in south. They are characterized mostly by gentle growth folds inside which only a few minor upthrust faults with offsets in the order of a few tens to hundreds of meters. The upthrust faults dipped mostly southeastward against to the northwestward subduction of paleo-Pacific as suggested in a previous study. They featured more like back-thrust growth tectonics, formed a broad NNE–SSW trending belt oblique to the northern margin of the South China Sea, and thus are inferred to have been the far-field impact of the Late Mesozoic subduction of the proto-Pacific.
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影响因子：
--
作者：
Liu Zhaoshu;Wei Changxing;Zhaobin Yan;Yang Shukang;Chen Senqiang
通讯作者：
Liu Zhaoshu;Wei Changxing;Zhaobin Yan;Yang Shukang;Chen Senqiang
影响因子：
--
作者：
D. Hayes;S. Nissen;P. Buhl;J. Diebold;Yao Bochu;W. Zeng;Yong-shun Chen
通讯作者：
D. Hayes;S. Nissen;P. Buhl;J. Diebold;Yao Bochu;W. Zeng;Yong-shun Chen
影响因子：
--
作者：
Peng Zhuo-lun
通讯作者：
Peng Zhuo-lun
DOI：
10.3969/j.issn.0001-5733.2011.12.021
发表时间：
2011-12
期刊：
Chinese Journal of Geophysics
影响因子：
--
作者：
L. Xi-wu;Liu Hong;Peng Xue-Chao
通讯作者：
L. Xi-wu;Liu Hong;Peng Xue-Chao
DOI：
--
发表时间：
2004
期刊：
--
影响因子：
--
作者：
Taichao Petroleum
通讯作者：
Taichao Petroleum