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.