New Early Cretaceous palaeomagnetic and geochronological results from the far western Lhasa terrane: Contributions to the Lhasa-Qiangtang collision.
New Early Cretaceous palaeomagnetic and geochronological results from the far western Lhasa terrane: Contributions to the Lhasa-Qiangtang collision.
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DOI：
10.1038/s41598-017-16482-3
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发表时间：
2017-11-24
影响因子：
4.6
通讯作者：
Li H
中科院分区：
文献类型：
--
作者：
Bian W;Yang T;Ma Y;Jin J;Gao F;Zhang S;Wu H;Li H
为了更好地约束拉萨-羌塘碰撞，对拉萨地体西部的多艾组熔岩流(~113116 Ma)和早白垩世杰嘎组灰岩进行了古地磁和地质年代学研究。经过详细的岩石磁学、岩相学和古地磁实验，利用主成分分析成功地从大多数样品中分离出特征剩余磁化方向。倾斜校正方向组的古极点位于69.1°N，319.8°E，95 = 为4.8°(N = 19)。磁化的主要来源与阳性折叠测试一致。结合已发表的拉萨和羌塘西部白垩纪地层的古地磁资料，我们对早白垩世单元的研究结果表明，这两个地体在早白垩世已经发生碰撞，拉萨地体具有相对东西走向，在整个白垩纪期间一直保持在相对稳定的古纬度。计算的拉萨地体西部白垩纪古纬度与欧亚大陆和蒙古国白垩纪古纬度的对比表明，自早白垩世以来，在纬度上的会聚分别为~1400 ± 290 km和~1800 ± 300 km。
To better constrain the Lhasa-Qiangtang collision, a combined palaeomagnetic and geochronological study of the far western Lhasa terrane was conducted on the Duoai Formation lava flows (~113–116 Ma), as well as on the Early Cretaceous Jiega Formation limestone. Following detailed rock magnetic, petrographical, and palaeomagnetic experiments, characteristic remanent magnetisation directions were successfully isolated from most samples using principal component analysis. The tilt-corrected direction groups yielded a palaeopole at 69.1°N, 319.8°E with A95 = 4.8° (N = 19). A primary origin for the magnetisation is consistent with positive fold tests. Our results from the Early Cretaceous units, combined with published palaeomagnetic data obtained from Cretaceous strata from the Lhasa and western Qiangtang terranes, show that these two terranes had already collided by the Early Cretaceous, the Lhasa terrane had a relatively east-west alignment, and it remained at a relatively stable palaeolatitude during the entire Cretaceous. Comparing the Cretaceous palaeolatitude calculated for the western Lhasa terrane with those from Eurasia and Mongolia suggests a latitudinal convergence of ~1400 ± 290 km and ~1800 ± 300 km, respectively, since the Early Cretaceous.
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影响因子：
2.8
作者：
Deenen, Martijn H. L.;Langereis, Cor G.;Biggin, Andrew J.
通讯作者：
Biggin, Andrew J.
影响因子：
2.8
作者：
Arason, P.;Levi, S.
通讯作者：
Levi, S.
影响因子：
6.1
作者：
Cao, Yong;Sun, Zhiming;Zhang, Lei
通讯作者：
Zhang, Lei
DOI：
10.1144/sp371.3
发表时间：
2012-01-01
期刊：
REMAGNETIZATION AND CHEMICAL ALTERATION OF SEDIMENTARY ROCKS
影响因子：
--
作者：
Jackson, Mike;Swanson-Hysell, Nicholas L.
通讯作者：
Swanson-Hysell, Nicholas L.
影响因子：
2.3
作者：
DAY, R;FULLER, M;SCHMIDT, VA
通讯作者：
SCHMIDT, VA