Geoelectrical Structure and Chromitite Prospecting of Sartohay Ophiolite Complex, NW China

Ophiolite suites are mostly the parent and host rocks for ophiolitic chromite deposits. The Sartohay ophiolite complex, which located in the West Junggar Ophiolite Belt in Xinjiang Autonomous Region, China, is the second-largest chromite mine district and one of the earliest ophiolite complex to undergo integrate chromitite exploration in China. Systematic gravity, magnetic, and electrical surveys have been conducted around the main rock body and vicinity of Sartohay, however, the spatial distribution of buried ophiolites remains unclear, so as to the understanding of the structure of the entire mining district and the deep resource prospects of the main ore belt. In 2016, Xinjiang Autonomous Region Bureau of Geology (Tacheng Geological Team) found a ore body with a thickness of some 2.3 m, another drilling carried out in 2025 intersected ore body of 5.28 m. A newly deposit group is found. Since then, the Tacheng Geological Team carriouted out a comprehensive survey, and the Institute of Geology and Geophysics, Chinese Academy of Sciences, conducted audio magnetotelluric sounding (AMT) in Sartohay ophiolite complex. The AMT profile is used to present the exploration achievements and discovery process of Sartohay. The internal electrical structure characteristics of the ophiolite within Sartohay and their correspondence with mineralization are analyzed. Using the resistivity-alteration-domain prediction model, favorable mineralization zones are predicted. It is prespected that a relatively large concealed ophiolite body may exist in the southern belt, and even its peripheral areas. This indicate greater resource prospects and exploration potential in the covered zone of the southern Sartohay district.