Paleomagnetic Secular Variations During the Past 40,000 Years From the Bay of Bengal
Paleomagnetic Secular Variations During the Past 40,000 Years From the Bay of Bengal
复制标题
孟加拉湾过去 4 万年的古地磁长期变化
DOI：
10.1029/2018gc008100
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发表时间：
2019-06
影响因子：
3.5
通讯作者：
Liu Jianxing
中科院分区：
文献类型：
--
作者：
Wang Shishun;Chang Liao;Xue Pengfei;Liu Shengfa;Shi Xuefa;Khokiattiwong Somkiat;Kornkanitnan Narumol;Liu Jianxing
由于记录不足，南亚古地磁的长期变化并没有得到很好的理解。本文通过对孟加拉湾中部4条海相沉积记录的叠加，得到了一条覆盖4万年的古地磁长期变化曲线。年龄模型基于放射性碳定年和岩心对比。采用逐级交变磁场退磁分离初级剩余物。岩石磁性测量结果表明，主要磁剩余物载体为单畴和伪单畴磁铁矿，无成岩蚀变迹象。我们的孟加拉相对古强度叠加与当地记录和PISO‐1500相对古强度叠加大致一致（Channell等，2009;https://doi.org/10.1016/j.epsl.2009.03.012）。通过古强度极小值识别出两次地磁偏移，分别与Mono湖（29 ~ 32 ka）和Laschamp偏移（38 ~ 40 ka）有关。我们得出结论，莫诺湖和拉尚游览是两个独立的事件。
Paleomagnetic secular variations in South Asia are not well understood due to insufficient records. In this study, we produce a new paleomagnetic secular variation curve covering the past 40,000 years by stacking four marine sediment records from the middle portion of Bay of Bengal. Age models are based on radiocarbon dating and core correlation. Stepwise alternating field demagnetization was used to isolate the primary remanent component. Rock magnetic measurements indicate that the primary magnetic remanence carriers are single domain and pseudo‐single domain magnetites with no sign of diagenetic alteration. Our Bengal relative paleointensity stack is broadly consistent with local records and the PISO‐1500 relative paleointensity stack (Channell et al., 2009; https://doi.org/10.1016/j.epsl.2009.03.012). Two geomagnetic excursions presented by paleointensity minima are recognized, which correlate to the Mono Lake (29–32 ka) and Laschamp excursion (38–40 ka), respectively. We conclude that the Mono Lake and Laschamp excursion are two separate events.
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影响因子：
5.2
作者：
L. McHargue;P. Damon;D. Donahue
通讯作者：
L. McHargue;P. Damon;D. Donahue
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影响因子：
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作者：
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M. Walczak;J. Stoner;A. Mix;J. Jaeger;G. Rosen;J. Channell;D. Heslop;C. Xuan