变质作用的PTt轨迹、地球动力学过程和金矿化

PRESSURE—TEMPERATURE—TIME PATHS OF REGIONAL METAMORPHISM GEODYNAMIC PROCESS AND GOLD MINERALIZATION

本文论述了典型的大地构造环境下变质作用的PTt轨迹及其反映的地球动力学过程对金矿化的控制作用,从PT演化的角度阐述了金矿床的成矿机理和成矿规律。

The tectonic settings and their geodynamic process for gold mineralization can be deduced from pressure—temperature—time (P—T—t) paths of regional metamorphism, thus it can be better to study the metallogenic mechanism and the distribution laws of gold deposits. A lot of evidences show most of gold deposits occur in convergent continental (or terrane' s) margins or continental extensional tectonics. The formation of gold deposits may be associated with the evolution of subduction zones which mostly have anticlockwise PTt paths, the collisional zone of arc—continent, continent—continent or terrane—terrane, which are mainly characteristics by clockwise PTt paths, and the continental extensional tectoncs or rifts, whose PTt paths are dominantly decompressional heating in pregression stage and isobaric cooling in retrogression stage.