Magnetic Fabric Constraints on the Cenozoic Compressional Strain Changes in the Northern Qaidam Marginal Thrust Belt and Their Tectonic Implications
Magnetic Fabric Constraints on the Cenozoic Compressional Strain Changes in the Northern Qaidam Marginal Thrust Belt and Their Tectonic Implications
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磁性组构对柴北缘边缘冲断带新生代挤压应变变化的约束及其构造意义
DOI：
10.1029/2019tc005989
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发表时间：
2020-04
期刊：
影响因子：
4.2
通讯作者：
Bao Jing
中科院分区：
文献类型：
--
作者：
Li Bingshuai;Yan Maodu;Zhang Weilin;Pares Josep M.;Fang Xiaomin;Yang Yongpeng;Zhang Dawen;Guan Chong;Bao Jing
重建柴北方冲断带的挤压应变历史，对于了解青藏高原东北部造山过程和阿尔金断裂带的构造演化具有重要意义。然而，对该地区的压应变变化研究甚少。柴北方冲断带中段河流-湖泊相红柳沟剖面新生代低场磁化率记录具有明显的各向异性。狮子沟组的磁组构以原生沉积磁组构为主，而下吕勒河组的磁组构则不确定，可能是由于砾岩岩性所致;而鲁乐河组中段至上犹沙山组的磁性组构均以反铁磁性赤铁矿和顺磁性组分为主，具有晶体学择优取向，主要是由褶皱前平行层缩短引起的胚胎构造组构。与红柳沟地区古地磁旋转结果相比，与旋转校正后的磁线理垂直的旋转校正后的压缩应变方向呈现出从~33 Ma前的近N-S到~10 Ma时的NE-SW的规律性趋势。结合来自柴北方的其他证据，我们将挤压应变方向的~45°连续顺时针旋转归因于沿着阿尔金山断层的显着走滑断层向柴北方边缘冲断带的传播，导致该地区出现显着的垂直轴顺时针旋转。
Reconstructing the compressional strain history of the northern Qaidam marginal thrust belt has significant implications for understanding the mountain building processes of the northeastern Tibetan Plateau and the tectonic evolution of the Altyn Tagh Fault. However, the variation of compressional strain in this region has rarely been studied. Here, we present Cenozoic anisotropy of the low‐field magnetic susceptibility records from the fluvial‐lacustrine Hongliugou profile within the middle part of the northern Qaidam marginal thrust belt. The magnetic fabrics of the Shizigou Formation are dominated by a primary sedimentary magnetic fabric, whereas those of the lower Lulehe Formation are undetermined, most likely due to the conglomerate lithology; in contrast, the magnetic fabrics of the middle Lulehe to Shangyoushashan Formations, all of which are dominated by antiferromagnetic hematite and paramagnetic components with crystallographic preferred orientations, are mostly embryonic tectonic fabrics induced by prefolding layer‐parallel shortening. Compared with previously reported paleomagnetic rotation results within the Hongliugou locality, the rotation‐corrected compressional strain directions that are perpendicular to the rotation‐corrected magnetic lineations exhibit a regular trend from nearly N‐S before ~33 Ma to NE‐SW at ~10 Ma. Integrated with other lines of evidence from the northern Qaidam Basin, we attribute the ~45° successive clockwise rotations of the compressional strain directions to the propagation of significant strike‐slip faulting along the Altyn Tagh Fault into the northern Qaidam marginal thrust belt that resulted in significant vertical axis clockwise rotations in the region.
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影响因子：
2.9
作者：
M. Mattei;F. Speranza;A. Argentieri;F. Rossetti;L. Sagnotti;R. Funiciello
通讯作者：
M. Mattei;F. Speranza;A. Argentieri;F. Rossetti;L. Sagnotti;R. Funiciello
影响因子：
2.9
作者：
Ó. P. Anchuela;Emilio L. Pueyo;A. P. Juan;A. Imaz
通讯作者：
Ó. P. Anchuela;Emilio L. Pueyo;A. P. Juan;A. Imaz
南天山白城凹陷克拉苏剖面磁性地层
影响因子：
3
作者：
Wang, Xin;Tian, Zhonghua;Pan, Xiaoqing;Shi, Linquan
通讯作者：
Shi, Linquan
青藏高原东北柴达木盆地新生代地层磁极性地层学、物源及古气候分析
影响因子：
4.9
作者：
Nie Junsheng;Ren Xueping;Saylor Joel E.;Su Qingda;Horton Brian K.;Bush Meredith A.;Che Wenhan;Pfaff Katharina
通讯作者：
Pfaff Katharina
影响因子：
4.2
作者：
Jimin Sun;W. Xiao;B. Windley;Weiqiang Ji;B. Fu;Jian‐Gang Wang;Chunsheng Jin
通讯作者：
Jimin Sun;W. Xiao;B. Windley;Weiqiang Ji;B. Fu;Jian‐Gang Wang;Chunsheng Jin