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In Sanqingshan and its surrounding areas, the magmatic action started from Meso-Neoproterozoic. And the most frequent and strongest magmatic action is the Yanshan Period of Mesozoic in which the granite formed a granite field of typical significance with features of "two belts and three types".

M-type oceanic plagiogranite in Meso-Neoproterozoic mixed distributes in metaperidotite in Xiwan in the north of Sanqingshan. According to the research of Shu Liangshu (1995), metaperidotite is the product of the basic component differentiation of ophiolite suite. In the fault contacting belt between metaperidotite and phyllite in Xiwan, there are highly-pressed and degenerative glaucophane rocks.

Granite in Yanshan Period is of features of "two belts and three types”.

"Two belts" are the north belt, copper factory-Yinshan tectonic magmatic belt, and the south belt, Huaiyu Mountain-Ling Mountain tectonic magmatic belt. The north belt is the intermediate-acidic hypabyssal porphyry-subvolcanic rock belt in mid-late Jurassic with features of little stocks, outputting bosses and negative landform; the south belt distributes in Huaiyu Mountain area and its southeast areas and is the cretaceous granite belt which is composed of Ling Mountain batholith and Huaiyu Mountain batholith. According to physical and geographic materials, these two mountains is connected in deep and forms the Huaiyu Mountain Chain which is the important scenic rok.

"Three types" means granites exposed in Sanqingshan are in three different genetic types those are Type I, Type S and Type A orderly according to their genetic time and their composition evolution from super acid and meta-alkalescence.

Copper factory-Yin Mountain tectonic magmatic belt is composed of hypabyssal granodiorite stock in Fujiawu, copper factory and Zhushahong and cryptovolcanic cryto-explosive dacite-porphyrite rock mass in Yin Mountain. According to the research of Shao Kezhong (1957) and Zhu Xun (1989), the above two are Type I granite which is intermediate-acid rock suite (SiO2 60%~66%), the crust-mantle mixed melting magmatite with 170~160Ma Rb-Sr timeline isotopic age value and the product of early orogenesis mid-late Jurassic. 

Huaiyu Mountain-Ling Mountain tectonic magmatic belt exposes two genetic types of granites. One is Ling Mountain composite rock mass in north-west orientation and of oval shape. The Wangxian Rock mass, located in the center of Ling Mountain composite rock mass, is poly-ring spot hornblende biotite monzonitic granite and contains plenty of microcrystalline diorite inclusion mixed by injection magma. It is positioned through the partial tension of fracture junctions between north-earth and north-west in later period of late Jurassic and earlier period of early cretaceous and its K—Ar isotopic age value is 140Ma; in later period of f early cretaceous, Ling Mountain rock mass is geode granite and its lithological character is hornblende biotite alkali-feldspar granite or biotite alkali-feldspar granite. It develops the geode structure and evolves to be rich in sodium (Na2O 3.7 %) which is the Type A granite based on researches of Jiang Yaohui (1999). The stretching and tension environment formed in late orogenic period is passively positioned along the residual pipelines of Wangxian Rock mass and the K—Ar isotopic age value of Ling Mountain Rock mass is 115.6 Ma. The Wangxian Rock mass located in the core of round composite rock mass is gentle and placid while the Ling Mountain Rock mass located in outer ring turns into peak cluster. Huaiyu Mountain granite Miscellaneous batholith exposed in Sanqingshan, Huaiyu Mountain and Damao Mountain areas, in overall is Type A granite and formed by multi-instrusion of magma and is the latest instrusion granite rock mass in this region whose K—Ar isotopic age value in main instrusion period is l15 Ma and K—Ar isotopic age value in complementary period is 96.6~87.4 Ma. Sanqingshan granite, located in the east part of Huaiyu Mountain batholith, is component of Huaiyu Mountain granite batholith.



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