Magnetostratigraphy of the Hominin Sites and Paleolakes Drilling Project (HSPDP) Baringo-Tugen Hills-Barsemoi core (Kenya)
Magnetostratigraphy of the Hominin Sites and Paleolakes Drilling Project (HSPDP) Baringo-Tugen Hills-Barsemoi core (Kenya)
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古人类遗址磁性地层学和古湖泊钻探项目 (HSPDP) Baringo-Tugen Hills-Barsemoi 核心（肯尼亚）
DOI：
10.1016/j.palaeo.2020.110190
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Cohen, Andrew S.
中科院分区：
文献类型：
--
作者：
Sier, Mark J.;Dupont-Nivet, Guillaume;Langereis, Cor;Deino, Alan L.;Kingston, John D.;Cohen, Andrew S.
古人类遗址和古湖泊钻探项目的主要目标是研究气候和环境变化之间的关系及其对东非人类进化的影响。为此，HSPDP在Baringo盆地（肯尼亚）的Chemeron地层中回收了一个228 m的岩芯。Chemeron地层的跨度约为370万年，从1.6到5.3 Ma，并产生了许多脊椎动物化石，包括化石人类。Baringo核的磁性地层学有助于年代框架。从整个岩芯的543个水平定期收集了567个单独的古地磁样品，其中264个使用热和交变场逐步退磁进行了处理。在大多数样品中，可以确定不同的低温（LT; 20 - 150 ° C）和高温（HT; 150 - 550 ° C）特征剩磁（ChRM）。典型的退磁行为和一些岩石磁性实验表明，钛磁铁矿作为HT ChRM的主要载体，具有普遍的二次套印在正常极性表示的LT组件。根据二次套印LT ChRM方向（分别与HT ChRM方向平行或反平行）识别正极性和反极性。我们的研究确定了四个古地磁反转解释为Matuyama-Gauss，Gauss-Kaena，Kaena-Gauss和Gauss-Mammoth转换。这些边界提供了年代地层联系点，可以与凝灰岩40 Ar/39 Ar测年得出的联系点结合起来（Deino等人，2020），共同表明，HSPDP Baringo核心的年龄范围为~3.3 Ma~~2.6 Ma。一致的古地磁和放射性同位素年龄约束被并入岩心的贝叶斯年龄模型（Deino等人，2020年）。
The principal objective of the Hominin Sites and Paleolakes Drilling project (HSPDP) is to study the relationship between climate and environmental change and the implications on human evolution in eastern Africa. For this purpose, HSPDP has recovered a 228 m core in the Chemeron Formation of the Baringo Basin (Kenya). The Chemeron Formation spans approximately 3.7 Myr, from around 1.6 to 5.3 Ma, and has yielded many vertebrate fossils, including fossil hominins. The magnetostratigraphy of the Baringo core contributes to the chronological framework. A total of 567 individual paleomagnetic samples were collected from 543 levels at regular intervals throughout the core and 264 were processed using thermal and alternative field stepwise demagnetizations. In most samples, distinct Low-Temperature (LT; 20–150 °C) and High-Temperature (HT; 150–550 °C) Characteristic Remanent Magnetization (ChRM) could be determined. Typical demagnetization behaviors and some rock magnetic experiments suggest titanomagnetite acts as the main carrier of the HT ChRM with pervasive secondary overprints in normal polarity expressed by the LT component. Normal and reversed polarities were identified based on the secondary overprints LT ChRM directions, either parallel or antiparallel to the HT ChRM directions respectively. Our study identified four paleomagnetic reversals interpreted as the Matuyama-Gauss, Gauss-Kaena, Kaena-Gauss and the Gauss-Mammoth transitions. These boundaries provide chronostratigraphic tie-points that can be combined with those derived from40Ar/39Ar dating of tuffs (Deino et al., 2020) and together indicate that the HSPDP Baringo core has an age range of ~3.3 Ma to ~2.6 Ma. The consistent paleomagnetic and radioisotopic age constraints are incorporated into a Bayesian age model of the core (Deino et al., 2020).
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撤回：Baringo-Tugen-Barsemoi (HSPDP-BTB13-1A) 岩心的年代地层学 – 40Ar/39Ar 测年、磁性地层学、地层学、层序地层学和贝叶斯年龄建模
DOI：
10.1016/j.palaeo.2019.109258
发表时间：
2019
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
A. Deino;M. Sier;D. Garello;C. B. Keller;J. Kingston;J. J. Scott;G. Dupont‐Nivet;A. Cohen
通讯作者：
A. Cohen
影响因子：
3.2
作者：
Gilbert, Christopher C.;Goble, Emily D.;Hill, Andrew
通讯作者：
Hill, Andrew
意大利焦亚陶罗剖面的古地磁和古生物学测年：布莱克事件的识别
影响因子：
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作者：
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通讯作者：
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岩石的磁各向异性：D.H. Tarling 和 F. Hrouda，伦敦，英国，1993 年，xi + 217 页，精装，40.00 英镑，ISBN 0-412-49880-4。
影响因子：
2.9
作者：
Kevin Kodama
通讯作者：
Kevin Kodama
DOI：
10.1098/rspa.1953.0064
发表时间：
1953-01-01
影响因子：
--
作者：
FISHER, R
通讯作者：
FISHER, R