Geologic evolution of SE Asia related with Gondwana drift.

我们在泰国、马来西亚等地的硅质岩、泥质岩和碳酸盐岩中进行了微体化石的野外调查。我们还测量了新的地质剖面，检查了地层和地质构造。我们的室内工作才刚刚开始，但我们已经在泰国西北部采集的硅质和泥质岩石中获得了一些放射虫和牙形刺的新材料。我们从暴露在清迈以北的方硅质岩中采集了放射虫化石的样本。这些放射虫标志着晚二叠世至早三叠世，并能够确定泰国东北部二叠纪和三叠纪的界线。我们的实地调查是在洛伊南部和王萨峰以东进行的。我们采集了许多含有较小有孔虫和褐藻类的样品，表明了石炭系和二叠系的界线。我们将能够在上碳…建立几乎完整的褐藻类分带在这些地区的石灰岩中有更多的泥质层和下二叠统。3)泰国半岛南部。古生物收藏品在Ko Samui和Hatyai地区进行。不幸的是，暴露在这些地区的Ratburi石灰岩被侵入的花岗岩变质了，但我们获得了关于岩石面貌的新数据。马来西亚西北部。我们在阿洛尔塞塔尔东部地区采集了许多塞曼古尔组的硅质岩样本。尽管前人的工作认为塞曼古尔组的地质时代为三叠纪，但这些硅质岩样品大多来自马来西亚中部的中到上二叠世。我们在本通-罗布缝合线沿线地区新采集了许多硅质岩和泥质岩样品。我们的微体古生物研究将有助于确定西布拉苏和东马来亚陆块碰撞的时间。6)马来西亚中东部。我们从磅阿华、仁嘉关和关丹东北部采集了石灰岩样品。这些样本中的大多数都产生了较小的有孔虫和褐藻类化石。较少

We made field survey to collect microfossils from siliceous, argillaceous and carbonate rocks in the following areas of Thailand and Malaysia. We also measured new geologic sections and checked stratigraphy and geologic structure. Our indoor works are just started, but we already obtained some new materials of radiolarians and conodonts in siliceous and argillaceous rocks collected from northwestern Thailand.1)Northwestern part of Thailand. We collected samples to obtain radiolarian fossils from the Fang Chert exposed north of Chieng Mai. These radiolarians are indicating Late Permian to Early Triassic and enable to settle the boundary of Permian and Triassic.2)Northeastern part of Thailand. Our field survey carried out in the southern area of Loei and east of Wang Saphung. We collected many samples containing smaller Foraminifers and fusulinaceans indicating the boundary of Carboniferous and Permian. We will be able to establish almost complete fusulinacean zonations in the Upper Carb … More oniferous and Lower Permian in limestones in these areas.3)Southern Peninsular Thailand. Paleontological collections were made in Ko Samui and the Hatyai area. Unfortunately, Ratburi Limestone exposed in these areas are metamorphosed by intruded granite but we obtained new data concerning lithofacies.4)Northwestern Malaysia. We collected many chert samples of the Semangool Formation in the eastern area of Alor Setar. Although the geologic age of the Semangool Formation was considered to be Triassic by the previous works, most of these chert samples indicate Middle to Upper Permian.5)Central part of Malaysia. We newly collected many chert and argillaceous rock samples from the area along the Bentong-Raub suture line. Our micropaleontological study will contribute to settle the timing of the collision of Sibumasu and East Malaya continental blocks.6)Central and eastern part of Malaysia. We collected limestone samples from Kampong Awah, Jenka Pass and northeast of Kuantan. Most of these samples yield smaller foraminifers and fusulinacean fossils. Less