Jurassic Paleomagnetism of the Lhasa Terrane—Implications for Tethys Evolution and True Polar Wander
Jurassic Paleomagnetism of the Lhasa Terrane—Implications for Tethys Evolution and True Polar Wander
复制标题
拉萨地体的侏罗纪古地磁——对特提斯演化和真正的极地漂移的启示
DOI：
10.1029/2022jb025577
复制
发表时间：
2022-12
期刊：
影响因子：
--
通讯作者：
Mark J. Dekkers
中科院分区：
文献类型：
--
作者：
Yiming Ma;Qiang Wang;Huapei Wang;Bo Wan;Shihong Zhang;Chenglong Deng;Dongyu Zheng;Qiang Ren;Tianshui Yang;Dan Wu;Di Zou;Jun Wang;Xiao Liu;Zhiqiang Kang;Wei Dan;Fei Han;Mark J. Dekkers
拉萨地体从冈瓦纳向亚洲漂移的历史对理解特提斯演化和真极漂移（TPW）具有重要意义。然而，目前还没有可靠的侏罗纪地层古地磁结果来重建其北行。对日喀则地区比马组地层进行了古地磁和地代学研究。结合Sangri地区之前的结果，我们的结果显示参考点（29.3°N, 90.3°E）在~ 180 Ma的古纬度为8±4°S。结合三叠纪至白垩纪的其他古地磁结果，我们的新结果表明拉萨地体运动从~ 220-180 Ma的~ 2 cm/yr加速到~ 180-170 Ma的~ 17 cm/yr。北羌塘地体和特提斯喜马拉雅的古纬度信息是根据满足5个标准的古地极来计算的，这些标准包括(a)构造控制，(b)确定的岩石年龄，(c)逐步退磁，(d)至少包含25个样品或8个地点，以及(e)提供了强大的磁场或反转试验。两个地块在北移过程中也表现出明显的加速，这可能与大洋板块俯冲有关。因此，所有冈瓦纳衍生的微大陆在向北运动的过程中似乎都有一个显著的加速度。此外，最近来自~ 155 Ma火山岩的古地磁结果将~ 170-130 Ma期间的整体北移细分为两个阶段，其中包括~ 170-155 Ma期间的南移和~ 155 - 130 Ma期间的北移。这些结果支持快速晚侏罗世TPW在~ 10 Myr时间跨度。
The drift history of the Lhasa terrane from Gondwana to Asia plays a crucial role in understanding the Tethys evolution and true polar wander (TPW). However, few reliable paleomagnetic results from Jurassic strata are currently available for reconstructing its northward journey. We performed a combined paleomagnetic and geochronological study on Bima Formation strata in the Xigaze area. Combined with previous results from the Sangri area, our results reveal a paleolatitude of 8 ± 4°S at ∼180 Ma for the reference point (29.3°N, 90.3°E). Along with other paleomagnetic results from the Triassic to Cretaceous, our new results suggest that the Lhasa terrane motion accelerated from ∼2 cm/yr during ∼220–180 Ma to ∼17 cm/yr during ∼180–170 Ma. Paleolatitude information of the North Qiangtang terrane and Tethyan Himalaya is calculated from paleopoles that meet five criteria, which include (a) structural control, (b) well‐determined rock age, (c) stepwise demagnetizations, (d) a minimum of 25 specimens or 8 sites are contained, and (e) robust field or reversal tests are provided. Both terranes also show significant acceleration during their northward motion, which may be related to oceanic slab subduction. Thus, all Gondwana‐derived microcontinents seem to share a significant acceleration during their northward motion. In addition, recent paleomagnetic results from volcanic rocks dated at ∼155 Ma subdivide the overall northward motion during ∼170–130 Ma into two stages, which include a southward drift during ∼170–155 Ma followed by northward motion during ∼155–130 Ma. These results support the fast Late Jurassic TPW during a ∼10 Myr time span.
登录
查看更多内容
早二叠世羌塘-旁佳大型火成岩省持续时间短：对新特提斯洋起源的启示
影响因子：
5.3
作者：
Wei Dan;Qiang Wang;J. Brendan Murphy;Xiu-Zheng Zhang;Yi-Gang Xu;William M. White;Zi-Qi Jiang;Quan Ou;Lu-Lu Hao;Yue Qi
通讯作者：
Yue Qi
影响因子：
3.5
作者：
Chao Wang;L. Ding;Liyun Zhang;P. Kapp;A. Pullen;Yahui Yue
通讯作者：
Chao Wang;L. Ding;Liyun Zhang;P. Kapp;A. Pullen;Yahui Yue
拉萨地体东缘上白垩统红层的古地磁：印度-欧亚大陆碰撞发生和欧亚大陆南部地壳纬度缩短的新制约
影响因子：
6.1
作者：
Yabo Tong;Zhenyu Yang;Junling Pei;Heng Wang;Yinchao Xu;Zongwen Pu
通讯作者：
Zongwen Pu
影响因子：
2.9
作者：
R. Voo
通讯作者：
R. Voo
影响因子：
64.8
作者：
P. Patriat;J. Achache
通讯作者：
P. Patriat;J. Achache