High-resolution magnetic stratigraphy of fluvio-lacustrine succession in the Nihewan Basin, China
High-resolution magnetic stratigraphy of fluvio-lacustrine succession in the Nihewan Basin, China
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泥河湾盆地河流湖相序列高分辨率磁性地层学
DOI：
10.1016/j.quascirev.2003.11.007
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发表时间：
2004-05
影响因子：
4
通讯作者：
Longrui Min
中科院分区：
文献类型：
--
作者：
Xisheng Wang;Zhenyu Yang;Reidar Lovlie;Longrui Min
摘要对河北省太尔沟泥河湾河湖沉积（40o12’52″N, 114o38’22″E）进行了详细的古地磁和岩石地磁调查。结果表明：磁性矿物学以磁铁矿和高矫顽力赤铁矿为主；磁铁矿主要赋存于灰黄色/黄褐色粉砂层和细粒黄砂层中，或作为碎屑成分，或作为磁铁矿低温氧化的产物。磁化率的显著变化往往与沉积物的岩性变化（即沉积物的颜色和粒度）有关，反映了地下水位的频繁下降/上升和沉积环境的变化。根据热、AF退磁实验的古地磁结果，给出了台儿沟出露湖河沉积的明确的极性地层学，包括3个正常磁带（Brunhes、Jaramillo和Olduvai亚时）和2个逆磁带（Matuyama）。这表明泥河湾盆地具有长而连续的地层记录，尽管沉积相和沉积速率不同。因此，我们认为台儿沟泥河湾湖相沉积开始于奥都瓦伊亚时，台儿沟剖面可作为生物年代学和高分辨率磁地层学测年工具。
A detailed paleomagnetic and rock magnetic investigation of Nihewan fluvio-lacustrine deposits at Tai’ergou (40o12′52″N, 114o38′22″E), Hebei Province of North China, has been carried out. The results show that the magnetic mineralogy is dominated by magnetite and high-coercivity hematite. Maghemite occurs mainly in the grayish-yellow/yellowish-brown silt layers and fine-grained yellow sand beds, either as a detrital component or as the result of low-temperature oxidation of magnetite. Distinct variations in magnetic susceptibility are always associated with changes in lithology, i.e., color and grain size of the sediments, reflecting the frequent lowering/ascendance of the water table level and change of sedimentation environment. Based on paleomagnetic results of thermal and AF demagnetization experiments, we present an unambiguous polarity stratigraphy for the exposed lacustrine–fluvial sediments at Tai’ergou consisting of three normal magnetozones including the Brunhes chron, the Jaramillo and Olduvai subchrons, and two reversed zones belonging to the Matuyama chron. This suggests that the Nihewan Basin carries a long, continuous stratigraphic record, albeit varying in sedimentation facies and sedimentation rates. Consequently, we concluded that the Nihewan lacustrine sediments at Tai’ergou commenced depositing at the onset of the Olduvai subchron, and the Tai’ergou Section can be used as a dating tool for biochronological and high-resolution magnetostratigraphic purposes.
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影响因子：
64.8
作者：
L. Zhou;F. Oldfield;A. Wintle;S. Robinson;J. T. Wang
通讯作者：
L. Zhou;F. Oldfield;A. Wintle;S. Robinson;J. T. Wang
影响因子：
--
作者：
B. Guo;R. Zhu;F. Florindo;Z. Ding;Jimin Sun
通讯作者：
B. Guo;R. Zhu;F. Florindo;Z. Ding;Jimin Sun
影响因子：
5.3
作者：
D. Heslop;C. Langereis;M. Dekkers
通讯作者：
D. Heslop;C. Langereis;M. Dekkers
影响因子：
5.3
作者：
B. Clement;D. Kent
通讯作者：
B. Clement;D. Kent
影响因子：
2.3
作者：
Jimin Sun;Tung-sheng Liu
通讯作者：
Jimin Sun;Tung-sheng Liu