高校地质学报2016，Vol.22Issue(1)：60-65,6.DOI:10.16108/j.issn1006-7493.2015081
云南兰坪-思茅盆地和老挝钾盐矿床物质来源新认识
New Ideas on the Origins of Potash Deposits in Yunnan China and Laos
摘要
Abstract
The Lanping-Simao basin in the southwestern China is located at the junction of the Eurasian and Indian Plates, and adjacent to a large potash deposit of Khorat Basin and Sakon Nakhon Basin in Thailand and Laos. Chinese scientists thought that the potash deposit in Lanping-Simao basin should be as large or important as that in Khorat Basin and Sakon Nakhon Basin. The relationship between Mengyejing potash in Lanping-Simao basin and potash deposits in the Sakon Nakhon Basin and Khorat Basins has long been discussed in many respects such as tectonic belt, depositional features, salt minerals, geochemical elements, and forming era. Many scientists thought that they had similar brine origins, and hydrothermal fluid was one important origin for the potash deposit. However, the ideas have received no supporting evidence. The type of hydrothermal fluid was not clear either. This study presentsδ18O andδD of halite inclusions from a ZK2893 core in Laos to provide isotopic evidence for the idea. The values ofδ18O are from-2.3 to 9.5‰ with an average of 2.9‰, while those of δD are from-78 to-150‰ with an average of-108.6‰. Most of δD was less than-90‰. The relationship between δ18O and δD shows that the hydrothermal fluid is metasomatic hydrothermal fluid which was originated from reactions between rainwater and surrounding rocks. Surrounding rocks are important origin for potash deposits. Most data were plotted near to the 150℃-curve in theδ18O-δD diagram. The possible forming temperature of halite inclusion in Laos could be about 150℃. On the other hand, the forming temperature of halite inclusion in Lanping-Simao Basin was about 145℃with the highest value of 170℃. The similar temperatures provide new evidence for their similar brine origins of the two basins.关键词
钾盐/石盐包裹体/氢氧同位素Key words
potash deposit/halite inclusions/oxygen and hydrogen isotope分类
天文与地球科学引用本文复制引用
李明慧,颜茂都,方小敏,张增杰,孙淑蕊..云南兰坪-思茅盆地和老挝钾盐矿床物质来源新认识[J].高校地质学报,2016,22(1):60-65,6.基金项目
973项目(2011CB403006 （）
2013CB956401) （）
中国科学院战略性先导专项B(XDB03020400) （XDB03020400）
国家自然科学基金项目(41271100 （）
41321061) （）
