The Geochemical Characteristics And Continental Geodynamics Of Lala Copper Deposit

This paper has done the thorough researches on the geochemical characteristics and continental geodynamics of LaLa copper deposit. The whole paper contains 7 chapters to expatiate.The paper summarizes the naissance and significance of continental geodynamics and it's mineralization, and points out that continental geodynamics is the key of confirming metallogenic system formation, evolvement, and regional structure evolvement. This research is a breakthrough of traditional mineralization theory, and also is the key of confirming the mineralization process and genetic mode of deposit, which is very important significance for ore-searching and exploration work in mining district. Based on analysis of regional tectonics, deposit signature, age and geochemical characers of Hekou group and gabbro, this paper points out rock origin and structure background and sets up the continental geodynamics evolvement sequence of Lala area. Based on the research of source of mineralizing materials and mineralizing fluid, confirm the attribute of a relation (content, water, heat) between different geologic body and deposit, inverse the mineralization in different continental geodynamics evolvement background by geologic body, and confirm the deposit mineralizing process and genetic mode in the end.Firstly, the ore body strictly lies in volcanic rocks of middle layer of hekou group of late Paleoproteozoic. Ores and hekou group have similar geochemical characters. The volcanic rocks, Hekou group, which belongs to alkalescence system erupted under the sea, formed in intercontinental cracks and aulacogen. According to what mentioned above, it is explained that Lala copper is associated with early syngenetic sediment diagenetic mineralization accompanying with hekou group eruption.Secondly, east-west axis' structure in this area constrain the association of deposits which show that north-south direction compression of Greenwiller movement caused the east-west axis' imbricate thrust-fold structure system and metamorphic mineralization in upper Proterozoic era(about 1000Ma).Thirdly, The spatiotemporal distribution of this gabbros closely relate to the deposits. Gabbro waspossibly the super mantle plume source whih the Rodinia supercontinent dividing in middle Proterozoic era(850Ma). It is deduced that mantle plume gabbro magma happening is the "engine" of large metal accumulation in late mineralization process of LaLa copper. The great heat and ore containing stratum caused " tide-producing resonance", that is the power of ore-forming element reactived, transfered and enriched, and finally lead to huge metal element enrichment in LaLa area.