Thermal History And Uplifting Process Of Tulasu Basin Western Tianshan

Deposits persist or vanish after complicated geological process,of which the uplift-exhumation has a great influence on deposit reserves.As Xinjiang's most important epithermal gold polymetallic ore zone,Tulasu basin is similar to metallogenic conditions and metallogenic settings in the southwest Pacific porphyry system and the adjacent large scale porphyry metallogenic system in the Western Tianshan Mountains and then prospecting breakthrough in deep region of this basin is expected.In this work,I use fission track thermochronology method through systematically sampling and fission track analysis in the typical deposits and surrounding area to research the uplift exhumation process of Tulasu basin,finally receiving some achievements as follows:1?The ages of fission track data distribute in the Mesozoic mainly in Jurassic and Cretaceous and the earliest is in Early Permian.Those data indicate that the geosphere temperature is higher than the closure temperature of apatite and zircon as result of most of the area had a experience of intense tectonic movement.2 ? Combining with Ar-Ar dating of potash feldspar and series of geological phenomenon,the thermal history simulation from the main metallogenic period(360Ma)of Tulasu basin is got.There are two uplift process during about 340 ? 330 Ma and320 ? nowadays and two settlement process during 360 ? 340 Ma and 330 ? 320 Ma and the rate of those processes is different Obviously.3?The uplift-exhumation model since the carboniferous of Tulasu basin is obtained.Different regions of Tulasu basin is diverse as the center has a minor degree with the rate of about 1.1 ? 1.5 m/Ma and both sides of the basin edge have a superior degree with the rate of about 2.8 ? 3.62m/Ma which is with the NNW main tectonic line as the axis of symmetry distribution.The Axi Au deposit and the Tabei Pb-Zn deposit has a massive uplift-exhumation as well as the Tawuerbieke Au deposit and Tieliekesayi Kaolinite-di Kai ore has a light uplift-exhumation.There is not many reserves and production of gold in the Tawuerbieke Au deposit at present probably because of the lack of strata denudation,and the ore deposit is still in the deepposition.There is a great potential for porphyry deposit prospecting in the shallow area of uplift – exhumation in Tulasu basin.