Nguồn gốc các đá thành tạo Granitoid đới Đà Lạt theo đặc điểm địa hóa đồng vị

The Origin of Granitoids in Dalat zone from isotopic - Geochemical Evidence

Gold metallogenic zoning and mineralized prospect in Dalat zone

Dalat structural zone was had formed in tectonic setting of continental margin arc in late Mesozoic, have given structural and metallogenic zoning. In this Dalat structural zone, gold is one of the few endogenous minerals is significant mineralization in the study and search - exploration. Endogenic gold distribution in Dalat zone are controlled by main factors such as: structure – locally tectonics (structural fold, brittle fault, structure of dome top of granitoid intrusions, tectonic setting), intrusion (related to gold mineralization), stratigraphy-lithology (environmental containments: volcanic, igneous, terrigenous sedimentary rocks, dykes). Based on analysis of factors of ore control, 138 gold mineral deposits, mineral occurrences and mineralized occurrences, and research several characteristic gold mineral doposits, and mineral occurrences, conducting gold metallogenic zoning, and evaluating the potential of these gold ore regions. These results mean a lot to innovated to next gold prospecting - mineral exploration.

GOLD MINERALIZATOIN FEATURES OF SUOILINH - SONGMADA (LINH SPRING - MADA RIVER) AREA AND ITS PROSPECTS

Suoilinh-Songmada area is situated in Vinhan ore region, in the SW of Dalat zone. Gold mineralization in this region occurred mainly in granitoid of Dinhquan complex, some of them are found in terrigenous-carbonate sedimentary rocks of formations: Dakrong and Mada. The host rocks were strongly altered mainly by sericitization, quartization, chloritization, and epidotization. The ores deposits were formed in veins, zones of veins that their direction is different: mainly in NE-SW, and NW-SE; secondary in sub longitude and sub-latitude. They are related to main fault in NW-SE direction. The mineral associations are mainly presented by pyrite, arsenopyrite, galena, sphalerite, chalcopyrite, native gold, and electrum, occupying 10-20%. The gold mineralization genesis is low-medium temperature hydrothermal, (125-267ºC) related to calc-alkaline granitoid which was formed in magmatic arc of active continental margin of ancient East Asia type, developed in Late Mesozoic. The ore deposit type is vein-shaped gold-quartz-sulfide; mineral types are: gold quart-pyrite-arsenopyrite and gold-quartz-polymetallic sulfide. With the above-mentioned features of spatial distribution and mineralization, gold mineralization of the Suoilinh Songmada area has high potential which should be studied more.