MICRO-BIOMINERALIZAITON OF AUTHIGENIC PYRITE AND ITS IMPLICATIONS FOR SEAFLOOR COLD SEEPS

Authigenic pyrite is widespread in marine sediments as a typical mineral for study of diagenesis and microbioactivities, and the mineralogy, geochemistry and isotopic composition of the mineral are all closely related to the deposition environment. It is not only useful for reconstruction of the evolutionary history of the depositional and diagenetic environment, but can also provide reliable information for exploration of offshore oil and submarine gas hydrate. In this article, we summarized and reviewed the authigenic pyrite formation mechanism, Fe-S isotope fractionation, biogeochemical processes and it relationship with the cold seep system. Upon the basis, we also bring up some focal questions associated with authigenic pyrite, especially the connection with the dynamic changes of gas hydrate, for discussion. The aim of this paper is to deepen the understanding of precipitation and diagenesis of the authigenetic pyrite and its implications for sedimentation environment, know more about the microbial catalysis factor and the significance of cold seep leakage to authigenic pyrite generation.