| Western Kunlun Orogen is located in the Northwest of Qinghai-Tibet Plateau. It adjoins Tarim Plate on the northward, connects the Qiangtang block with Karakorum Fault on the southward. Altyn Tagh comparts Western Kunlun Orogen stretches into Iran and Pakistan along the Pamir Mountain Area. It is the important part of Central Orogenic Belt of China,has complicated tectonic evolution process, and the important belt on which people research the uplifting and evolution of Qinghai-Tibet Plateau. Because of its abominable natural conditions, it is also one of most important belts in China.This paper is mostly researched on the eastern part of Western Kunlun Orogen, some contents of it come down to the whole Western Kunlun area. The major achievements gained by the author based on the two years studies,are indicated as follows:1. The author clears up the Precambrian strata systematically, based on the former researchers' studies and our own field and indoor researches. The author set up the early-Precarabrian Hongliutan Group (unofficially stratigraphic unit), and for the first time found the granulite and retreated metamorphic granulite faces metamorphic rock in early-Precambrian Hongliutan Group and Karakorum Group. Based on the rock association,metamorphism anddeformation characteristics, and the age-dating data, the author departs Precambrian of Western Kunlun into three tectonic-rock-stratum units as early-Precambrian (Ar-Pti) metamorphic crustal rock series tectonic unit, Mesoproterozoic (Pt2) volcanic-sedimentary rock series tectonic unit (arc-trench system) and Neoproterozoic-Sinian(Pt3-Z) after-orogenic cover strata. According to the isotopic age-dating data, the author mergers the era of the Paleoproterozoic Ailiankate Group into Mesoproterozoic Jixian period.2. The study on the Jixian period Ailiankate Group of the eastern part of Western Kunlun put forwards that the lower part of the Group is typical converse evolution bimodal volcanic rock association, the upside is flysch, on the top there is a spot of molasses. The sedimentary series denotes the formation, development and vanish of the sedimentary basin. The geochemical characteristics of the bimodal volcanic rock indicate that the early rhyolite comes from partial melting of continental crust. The laminar alkaline basalt, interlining the rhyolite, have high S REE and typical trace element characters of intraplate basalt , and the basalt , locates in the upside of the bimodal volcanic rocks ,has the geochemical characteristics of oceanic tholeiite.Based on the stratigraphical and rock geochemical characteristics,the author points out that the bimodal volcanic rock is formed in the continental margin rifting background. Intergrating flysch's sedimentary characters,the author indicates that Ailiankate Group is formed in the rear arc basin tectonic background.3.For the first time, the author identifies Mesoproterozoic JLxian period arc volcanic rock series (Taxidaban Group) at Yutian-Minfeng district of Western Kunlun. This arc volcanic series mainly consists of (basaltic) andesite,and thimbleful rhyodacite and marble stripe. The thickness of the crop out is more than 2000m. The (basaltic)andesite has ultra-low EREE and typical arc volcanic rock trace element characters. The rhyodacite has high Z REE and the mighty similar REE chondrite-normalized pattern with that of the (basaltic) andesite,which suggests they both come from the same source region,formed with the interaction between the subduction oceanic crust and mantle material ,and provides important geological evidences for the researching work of the evolution of Mesl-Neoproterozoic plates in this area.4. Based on the detailed field and indoor studies on the testing data, the author brings forward different viewpoints on "Kudi ophiolite", the author considers the ultramafic rock in "Kudi ophiolite" is Alaskan-type annular complex,not the metamorphic peridotite of upper mantle. The basalt at Yixiekegou of Kudi and the upper so-called ophiolitiferous f lysch is a suit of nonmetamorph...
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