U.S.-Thailand Cooperative Research: Field Search in NE Thailand for Craters Associated with the Formation of the Australasian Tektites

小行星9316561 这一建议要求资金允许约翰·T博士。2008年12月10日，洛杉矶加州大学地球物理和行星物理研究所的Wasson教授与泰国矿产资源部地质调查司退休司长Kaset Pitakpaivan教授一道开展为期18个月的研究方案，以确定泰国东北部与澳大拉西亚玻璃陨石形成有关的陨石坑的位置。 实地工作将由美国和泰国各约五名成员的合作小组进行。 理论认为，玻璃陨石，高二氧化硅（60 - 80%）和高氧化铝（10 - 15%）含量的玻璃，是由混合良好的大陆沉积物（如页岩或土壤）在小行星或彗星撞击地球时熔化而产生的。 小的玻璃陨石，通常重量小于300克，形状为圆盘、哑铃和泪珠，被认为是在大气中旋转时由液体凝固形成的。 较大的层状玻璃陨石被认为是在地面上由硅酸盐熔体的水坑形成的。 将根据泰国合作者提供的遥感数据确定有希望的研究地点。 从野外返回的岩石样品将通过光学显微镜、核磁共振和其他技术来检查冲击石英，以寻找冲击效应的证据。 确认玻璃陨石的撞击起源需要鉴定陨石坑或陨石坑，但没有发现。 虽然大多数研究人员认为，玻璃陨石是在一个直径约10公里或更大的陨石坑中产生的，但PI提出，需要额外的较小陨石坑来解释从海南岛通过柬埔寨到泰国的1，200公里距离上发现的层状玻璃陨石。 密度最高的澳大拉西亚玻璃陨石位于泰国东北部的东南角。 地质学家对这一研究问题非常感兴趣，目前的项目可能有助于解决这一领域关于这些玻璃陨石形成的不确定性。 PI和他的合作者是该提案领域备受尊敬的研究人员。 该项目与东亚和太平洋计划的目标有关，该计划旨在通过交流科学信息、思想、技能和技术以及通过在互利问题上的合作，提高美国科学家和工程师与亚太地区同行之间的合作水平。 ***

9316561 Wasson This proposal requests funds to permit Dr. John T. Wasson, Institute of Geophysics and Planetary Physics, University of California, Los Angeles, to pursue with Professor Kaset Pitakpaivan, Retired Director, Geological Survey Division, Department of Mineral Resources, Thailand, for a period of 18 months, a program of research to locate and identify craters in northeast Thailand associated with the formation of the Australasian tektites. Field work will be conducted by collaborating U.S. and Thai teams of about five members each. Theory holds that tektites, glasses with high silicon dioxide (60-80%) and high aluminum oxide (10-15-%) contents, are produced by the melting of a well-mixed continental sediment such as shale or soil during the impact of an asteroid or comet with the Earth. Small tektites, usually weighing less than 300 g and in the shape of disks, dumbbells, and teardrops, are believed to have been formed by the solidification of a liquid while spinning in the atmosphere. Larger layered tektites are believed to have been formed on the ground from puddles of silicate melt. Promising research sites will be identified from remote sensing data provided by the Thai collaborators. Rock samples returned from the field will be examined for shocked quartz by optical microscopy, nuclear magnetic resonance, and by other techniques to search for evidence of shock effects. Confirmation of the impact origin of tektites requires the identification of the crater or craters, but none has been found. While most researchers are of the opinion that the tektites were produced in a single crater with a diameter of about 10 km or more, the PI has proposed that additional smaller craters are required to account for the layered tektites which are found across a 1,200 km distance from Hainan Island through Cambodia to Thailand. The highest density of Australasian tektites is found in the southeast corner of northeast Thailand. The research problem is of great interest to geologists, and the present project may do much to resolve the uncertainty in this field regarding the formation of these tektites. The PI and his collaborators are highly respected researchers in the field of this proposal. This project is relevant to the objectives of the East Asia and Pacific Program which seeks to increase the level of cooperation between U.S. scientists and engineers and their counterparts in the Asia-Pacific region through the exchange of scientific information, ideas, skills, and techniques and through collaboration on problems of mutual benefit. ***