Research Of Geological Characterristics And Metallogenic Regularity Of Manganese In Heishui Area In Sichuan Province

Heishui area of Sichuan locats at western margin of the Songpan-Ganzi fold system slot, the eastern of BaYan Hala miogeosyncline fold belt, and ShiPan guan-Motian arcuate tectonic beltthe which belongs to the Yangtze Platform,is one of the important iron and manganese mineralization belt system. This dissertation aims to research the geological characteristics and discuss the metallogenic regularity of manganese in Heishui area on the integrated use of geology, structural geology, sedimentology, facies ancient geography, metamorphic petrology, also new theories and methods on metallogenic belt geology research and exploration.Through the detailed research and discuss on characteristics of typical manganese deposit of which include its characteristics of geology, type of deposit, ore deposit characteristics, ore characteristics, source materials of ore forming, regional geological structural, magmatic, metamorp-hic rock, geochemistry, geophysics, we can demonstrat systematically that the original source of minerals in Heishui region of Sichuan mainly come from the volcanic faulty activities in Triassic, westernal paleo-Ganzi miogeosyncline of Jinsha River, Yidun area which brought iron and manganese currents. Western part of Longmen moutain remant arc erosion area’s debris flow brought the source materials of diagenesis.It is the sediment metamorphic type that Heishui manganese deposit is. The ore bearing horizon is seated in the lower part of the sedimentary cycle’s transition of the Permian-Triassic group which is a set of metamorphic rocks and sedimentary carbonate rocks. The sedimentary cycle constraints the enrichment of the manganese deposit which has closely relationship in sedimentary sequence with the magnetite that compose the top, bottom or staggering in layers with manganese and forming in the researching area. Composite ore has a obvious boundary between the two ores in this area. The numbers in manganese layers will be increasing with the growing numbers in magnetite single layers, which will make the manganese compositing layers thicker and the higher grade trend in industrial manganese ore will occur obviously.Phyllite and low grade metamorphic such as metamorphic clastic rocks in which the manganese layers integrat are developing widely in Heishui area and also in the region. The manganses layers with its upper and lower layers make up the stratums which are stratigraphic from siltstone layer â†'iron layerâ†'siltstone layer with mangansesâ†'iron layerâ†'mangansesâ†'limestone, all of which are components of a transgressive cycle in which the manganese occurs in the middle horizon. The boundaries among manganese layers, upper and bottom iron layer are clear. The characteristics of manganese layer are similar to siltstone layer with manganese with any significant enrichment of regenerative transformation, under the circumstances we can believe that the manganese layers already had formed before the deposition, and then there was the deterioration process to generate new minerals manganese.It can been seen from the research that the material sources of manganese BoCigou group may be bidirectional. With the periodic motion of the Tethys ocean stream, the layers accompanied by alternately stacking underflow material deposition.Diagenetic debris flows may come from the ancient island with which surrounded Longmen mountain.The mineralization may be derived from debris flows in the Middle Triassic of India, Tethys height expansion, the westernal of Songpan-Ganzi geosyncline and the Triassic deep fault which give birth to the volcanic eruption. The manganese-rock series are currenting to the east on the rugged island in the sea area, including ferromanganese sheeted debris flows with Tethys ocean. After bocked by the rement arc erosion area of Longmen mountain and compensated with sedimentary material, it formed iron-manganese and silt(mud)rhythm precipitation in underwater depressions of Malcolm basin.It matches to that manganese in Heishui area deposit wiedly with a large-scale in low-grad.Through the summary we can learn about the relationship among sedimentary, metamorphis and mannganese deposit of this area. Along the tectonic evolution of the area, the mineral that is a metamorphic-sedimentary type formed through sedimentary and metamorphic procedure. Several recommendations should be made based on the theoretical of mineralization in the area.