Rare Earth Element Occurrence Database of the Tien Shan Region, Central Asia

Central Asia, site of the historic Silk Road trade network, has long been a conduit for the movement of people, energy, and mineral resources between Europe and Asia. Once part of the former Soviet Union, this region was and continues to be an important producer of base and precious metals, rare metals (RM), including niobium, tantalum, and beryllium, and a past producer of rare earth elements (REE). The Tien Shan and Pamir Mountains regions, encompassing parts of Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, and Turkmenistan, are of significant interest for mineral exploration as these regions are thought to host substantial undeveloped and undiscovered resources of REE and RM. Based on this legacy, and as an emerging REE and RM producing region, the Central Asian countries are implementing mining sector reforms to create a more attractive investment environment for domestic and foreign mining interests. During the most recent increase in REE prices, beginning in 2009 and culminating in a dramatic price spike in 2011, much mineral exploration activity for REE was undertaken in Kazakhstan, Kyrgyzstan, and Tajikistan. In order to assess the mineral potential for REE in Central Asia, the U.S. Geological Survey began in 2012 compiling an inventory of REE-RM occurrences in that region. These occurrences range in development status from mineral showings to previously developed deposits. Completed in 2016, the inventory consists of 384 REE-RM occurrences, including 160 in Kazakhstan, 75 in Kyrgyzstan, 60 in Tajikistan, 2 in Turkmenistan, and 87 in Uzbekistan. The inventory dataset includes detailed information on location, mineral deposit type, geology, production, resources, and development status. Four important groups of REE-RM mineral deposit types were recognized: (1) carbonatite and alkaline igneous rock-related deposits; (2) pegmatite and skarn/greisen deposits; (3) weathered-crust deposits, including laterite, derived from weathering of other REE-RM mineral deposits; and (4) sediment-hosted uranium deposits. This inventory is released as a database in two formats, a Microsoft Excel workbook and an ESRI ArcGIS 10.5 point feature class dataset built from the Excel workbook. The Excel workbook also includes data field definitions, explanations of the terminology and abbreviations, and references.作为古丝绸之路贸易网络的枢纽地带，中亚长期以来是连接欧亚大陆间人员、能源与矿产资源流动的重要通道。该地区曾为苏联加盟共和国，过去与现在均为贱金属、贵金属以及铌、钽、铍等稀有金属（Rare Metals, RM）的重要产出地，同时也曾是稀土元素（Rare Earth Elements, REE）的生产区域。覆盖哈萨克斯坦、吉尔吉斯斯坦、塔吉克斯坦、乌兹别克斯坦与土库曼斯坦部分区域的天山及帕米尔高原山区，因被认为蕴藏大量未开发及尚未探明的稀土元素与稀有金属资源，成为矿产勘探的重点区域。依托这一产业基础，且作为新兴的稀土元素与稀有金属产出区域，中亚各国正在推进矿业部门改革，以期为国内外矿业投资者营造更具吸引力的投资环境。在2009年启动、并于2011年达到价格峰值的最近一轮稀土元素价格上涨周期中，哈萨克斯坦、吉尔吉斯斯坦与塔吉克斯坦境内开展了大量稀土元素矿产勘探活动。为评估中亚地区的稀土元素矿产潜力，美国地质调查局（U.S. Geological Survey）于2012年启动该区域稀土元素-稀有金属矿点清单的编制工作。这些矿点的开发状态涵盖从矿产显示点到已开发矿床的全范围。该清单于2016年完成，共收录384处稀土元素-稀有金属矿点，其中哈萨克斯坦160处、吉尔吉斯斯坦75处、塔吉克斯坦60处、土库曼斯坦2处、乌兹别克斯坦87处。本清单数据集包含矿点位置、矿床类型、地质情况、开采情况、资源量与开发状态等详细信息。本次研究共识别出四类重要的稀土元素-稀有金属矿床类型：（1）与碳酸岩及碱性火成岩相关的矿床；（2）伟晶岩与夕卡岩/云英岩矿床；（3）风化壳矿床（包括由其他稀土元素-稀有金属矿床风化形成的红土型矿床）；（4）沉积型铀矿床。本清单以两种格式发布为数据库：一是Microsoft Excel工作簿，二是基于该Excel工作簿构建的ESRI ArcGIS 10.5点要素类数据集。该Excel工作簿还包含数据字段定义、术语与缩写说明以及参考文献列表。