Wide shelves as discriminators between hinterland tectonic and intra-basin rifting signals
Wide shelves as discriminators between hinterland tectonic and intra-basin rifting signals
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DOI：
10.1016/j.epsl.2023.118347
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发表时间：
2023-10
影响因子：
5.3
通讯作者：
Li Liu;Jianhui Han;Jianxiang Pei;D. Stockli;Li You;L. Stockli;Jinyu Zhang;C. Gong;Dicheng Zhu
中科院分区：
文献类型：
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作者：
Li Liu;Jianhui Han;Jianxiang Pei;D. Stockli;Li You;L. Stockli;Jinyu Zhang;C. Gong;Dicheng Zhu
解读全球源-汇系统中相互交织的构造和气候驱动因素仍然是地球科学的一个重大挑战。研究表明，南海北方的广阔陆架是与腹地构造活动和盆地裂陷有关的重要标志。裂谷作用是宽陆棚序列中碎屑锆石（DZ）信号变化的主要驱动力。DZ数据显示，与海底扩张和地壳伸展同步的盆内沉积物来源的比例越来越大（约100%）。32-16 Ma），盆外物源逐渐增加，直至更新世，与裂陷后热沉降同步。这些DZ的变化是免费的最强的新生代构造运动，东藏东喜马拉雅造山带的隆升，因为约。23 Ma，尽管这种区域性隆升控制了琼东南盆地中央峡谷补给的整个南海北方盆地深水盆地区的DZ信号变化。此外，全球海平面上升的中新世气候最佳驱动的影响不大，在陆架到盆地系统的沉积物输送。在这项研究中，大陆架和深盆之间的DZ变化趋势的强解耦强调了宽大陆架在区分全球源-汇系统中不同的同种异体驱动因素的重要性。
Decoding interwoven tectonic and climatic drivers in global source-to-sink systems remains a major challenge in Earth science. This study demonstrates that the very wide shelf in the northern South China Sea acted as a critical discriminator of signals related to hinterland tectonism and basin rifting. The rifting process is the main driver of variations of detrital zircon (DZ) signals in the succession of the wide shelf. DZ data show an increasing proportion of intrabasinal sediment source that is in phase with seafloor spreading and crustal extension (ca. 32–16 Ma), and then a gradual increase of extrabasinal source until the Pleistocene, in step with post-rifting thermal subsidence. These DZ variations are free of the strongest Cenozoic tectonism, the uplift of the eastern Tibet-Himalayan orogen since ca. 23 Ma, although this regional uplift dominated the DZ-signal variations in the entire deep-water basinal areas of the northern South China Sea basins fed by the Central Canyon of the Qiongdongnan Basin. Moreover, rising of global sea-level driven by the Miocene Climatic Optimum had little impact on sediment delivery in the shelf-to-basin system. The strong decoupling of DZ-variation trends between the shelf and the deep basin in this study underscores the importance of wide shelves in distinguishing different allogenic drivers in global source-to-sink systems.