Deseado Massif hot spring deposits (Late Jurassic, Patagonia, Argentina) and their association with epithermal systems

GUIDO, D.; CAMPBELL, K.

Congreso; Mineral Systems of the Pacific Rim Congress 2019; 2019

The Deseado Massif has about the same number of sinters and travertine chemicalprecipitate deposits, but a larger quantity of shallow siliceous deposits when weinclude cherts and silicified volcanic rocks, supporting the overall neutralalkali chloride dominant nature of the hydrothermal fluids. About one-third of the hot spring localities, and half of the activeDeseado Massif epithermal mines, are in close spatial relationship (<5 km). Therefore,defining Jurassic paleosurfaces can be considered as a relevant prospectivetool. Finally, larger(i.e., a proxy for long-lived fluid flow and/or geographically extensivehydrothermal activity) and proximal hot spring deposits contain most of thegold and silver resources, highlighting the importance of proper discriminationof facies assemblageswithin the Deseado Massif hot spring deposits, that can also be used tovectorize in prospecting the region.