Mineralogy and chemistry of sulfide deposits drilled from hydrothermal mound of the Snake Pit active field, MAR

Abstract

The Snake Pit active hydrothermal field was discovered at 23°22′N on the Mid-Atlantic Ridge during ODP Leg 106. Among the 10 holes drilled in the mound at the foot of an active chimney, only three (649B, 649F and 649G) had substantial recovery, and produced cores of unconsolidated hydrothermal deposit. Mineralogical assemblages show evidence of sequential precipitation, and absence of equilibrium. Major sulfide phases are pyrrhotite, pyrite, Fe, Cu sulfides, marcasite, and sphalerite. Three types of samples are distinguished on the basis of textures and mineral assemblages. -from Authors