MIDDLE DEVONIAN FAUNA OF THE HYDROTHERMAL SULFIDE HILLS OF THE URALIAN PALEOOCEAN

Abstract

The discovery of hot springs in the pelagic and back-of-the-arc zones of spreading, around which there exist ecosystem communities in which bacteria utilize the energy contained in energy-rich mineral compounds, has drawn attention to ophiolitic sulfide formations. The latest finds from the Sibay copper-pyrite ore deposit (the western flank of the Magnitogorsk synclinorium, southern Urals) with the finds of perihydrothermal fauna in the ophiolites of Cyprus and Oman suggest that during the Devonian Period there existed in the Uralian Ocean not only shallow-water, but also pelagic centers of hydrothermal sulfide population, and that the latter were actually dominant. The Sibay copper-pyrite ore deposit lies in the Middle Devonian (Eifelian-Givetian) Magnitogorsk-Mugodzhary island-arc system on the margin of the Uralian Paleoocean.