Discovery, Geological Characteristics and Genesis of Sedimentary Metamorphic Manganese Carbonate Deposit in Muhatayi, Western Junggar, Xinjiang

The discovery of the Muhatayi manganese deposit marks a breakthrough in the exploration of manganese deposits in the western Junggar region. The manganese deposit is located in the northern part of the Muhatayi ophiolite melange belt in West Junggar, and the ore body is hosted in siliceous rocks. In the deep part, it appears as siliceous rocks with variegated breccia, distributed in a layered manner. According to rock and mineral identification, phase analysis, back scattering, and laser Raman analysis, the surface manganese is manganese oxide, and no manganese carbonate is found; Deep manganese consists of Rhodochrosite, a small amount of Rhodonite and variant manganese triclinite, and most of Rhodochrosite occurs in tectonic hydrothermal veinlets. More than 10 manganese oxide ore bodies have been delineated on the surface, and 4 Manganese carbonate ore bodies have been delineated in the deep. The Manganese carbonate may be produced in the primary layer of manganese. The surface manganese ore body has a large scale along the strike direction, extending up to 2 kilometers on both sides, and the ore body has expanded on the east side, resulting in a significant increase in ore veins. The average grade of deep Manganese carbonate ore body is 17.95%, reaching the general industrial index of lean manganese ore, indicating that the area has good manganese prospecting potential. The deposit type is a sedimentary metamorphic hydrothermal superimposed and reformed manganese deposit that occurs in the ophiolitic melange, which is the first discovery of this type of manganese deposit in the western Junggar region. In recent years, there have been more and more reports about the discovery of manganese deposits in ophiolite melange. The oceanic slab strata in the accretionary Orogenic belt are the best places for the occurrence of ancient oceanic Manganese nodule. The deep-sea pelagic Radiolaria siliceous rocks are an important part of the oceanic slab strata, with good prospects for ore prospecting.