Early Cretaceous tectonic events implied in the time-lag between the age of radiolarian chert and its metamorphic basement in the Bantimala area, South Sulawesi, Indonesia
Early Cretaceous tectonic events implied in the time-lag between the age of radiolarian chert and its metamorphic basement in the Bantimala area, South Sulawesi, Indonesia
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DOI：
10.1111/j.1440-1738.1994.tb00097.x
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发表时间：
1994-06
期刊：
影响因子：
1.5
通讯作者：
K. Wakita;Munasri;J. Sopaheluwakan;I. Zulkarnain;Kazuhiro Mlyazaki
中科院分区：
文献类型：
--
作者：
K. Wakita;Munasri;J. Sopaheluwakan;I. Zulkarnain;Kazuhiro Mlyazaki
摘要 南苏拉威西班提马拉杂岩主要由混杂岩、燧石、玄武岩、超镁铁质岩和高压型变质岩组成。从 10 个燧石样品中提取了保存完好的放射虫，并从 Bantimala 杂岩体的 5 个片岩样品中对白云母进行了 K-Ar 年龄测定。燧石中的放射虫组合被指定为白垩纪中期（阿尔布阶晚期 - 塞诺曼阶早期）年龄，而片岩中的 K-Ar 年龄数据范围为 132 Ma 至 114 Ma，除了一个含有稀有白云母的样本外。放射虫燧石不整合地位于班提马拉杂岩体的片岩之下。地层关系以及来自燧石和底层片岩的这两种年龄数据的时间滞后表明，在阿尔布-塞诺曼期海侵期间，该地区发生了短时构造事件，紧随其后的是该地区构造活动的快速减弱。
Abstract The Bantimala Complex of South Sulawesi consists mainly of melange, chert, basalt, ultramafic rocks and high pressure type metamorphic rocks. Well-preserved radiolarians were extracted from 10 samples of chert, and K-Ar age dating was done for muscovite from five samples of schist of the Bantimala Complex. The radiolarian assemblage from chert is assigned middle Cretaceous (late Albian-early Cenomanian) age, while the K-Ar age data from schist range from 132 Ma to 114 Ma except for one sample with rare muscovite. The radiolarian chert is unconformably underlain by schist in the Bantimala Complex. The stratigraphie relationship and the time lag of these two kinds of age data from chert and underlying schist suggest short-time tectonic events immediately followed by a quick waning tectonism in this region during the Albian-Cenomanian transgression.