Datos isotópicos, mineralógicos y modelo genético propuesto para los yacimientos de plomo, zinc y plata de Fresnillo, Zacatecas

Abstract

In the Fresnillo mining district in central Zacatecas State, the lead-zinc-silver deposits are in the form of mantos, ore chimney and veins. The geologic information, available mainly from the Fresnillo mine, indicates that the mantos are within Lower Cretaceous marine clastic sedimentary rocks, which were folded together during the early Eocene. One of the mantos, together with the under- and overlying sedimentary rocks, was intruded by a small vertical quartz monzonite stock, probably toward the end of the Eocene. Along the south margin of this intrusive, there is an ore chimney that extends about 50 m below and about 50 m above the general level of the intruded manto. Of the numerous veins of the Fresnillo mine, one of them crosscuts the intrusive, whereas several others cut the folded mantos, but none of these cut the overlying rhyolitic rocks which are considered to be Miocene in age.

Isotope analyses of lead from the manto and vein ores indicate an almost identical composition and the leads are of the J-type... In order to continue, download the full paper in PDF.