Mushugay-Khuduk REE-Fe-F deposit in Southern Mongolia
Rundqvist, Inga K.; Baskina, Valentina A.; Ontoev, D. O.
published: Nov 27, 1995
ArtNo. ESP136000501009, Price: 19.00 €
Mushugay-Khuduk REE-Fe-F-Sr prospect was revealed in 1974 in Gobi desert, Southern Mongolia (44° 10'N, 104° 40'E). Ores occur as a sequence of late-magmatic to hydrothermal bodies: Stocks, lenses, brectiated zones, veins, and stockworks, composed of REE-apatite, titanomagnetite, phlogopite, carbonates, fluorite, celestite, barite, bastnaesite, and others, rich in REE, F, P, Sr. Total content of REE in various types of ores, according to sporadic sampling, vary from 0.1 to 2-8 %. Economic mineralization is connected with a local potassium rich alkali volcanic-plutonic suite, 158-135 m.a., composed of melanephelinites-melaleucitites, trachytes, trachy-rhyolites, shonkinite- and syenite-porphyries. K-Ar age of early stage ores, by phologopites, 143 m.a. Temperature range of ore-forming process, according to fluid inclusions data is from 700° to 350°-150° C. Mushugay prospect, tentatively evaluated as a middle-range deposit with reserves of 3 metric million tonnes REE, is not finally explored. Authors regard Mushugay deposit as a variety of a group of Fe-F-REE deposits, affiliated to alkali basaltic suites and including deposits like Mountain Pass (Calif.), Pea Ridge (Missouri), Bayan Obo (China) and others. Discovering of the Mushugay prospect was a result of combining remote sensing and morphostructural methods with analysis of magmatic anomalies.