Types and distribution
Types and distribution of copper mines. According to their geological and industrial types, they can be divided into: (1) porphyry type, (2) sandstone type, (3) copper-nickel sulfide type, (4) pyrite type, (5) copper-uranium-gold type, (6) native copper type, (7) vein type, (8) carbonatite type, (9) skarn type. Porphyry type: Porphyry copper ore is a copper deposit with large reserves and low grade that can be mined by large-scale mechanized open-pit mining. The ore reserves often reach hundreds of millions of tons, and the copper grade is often less than 1%. According to statistics on 103 porphyry deposits in the world, the average ore volume of a single deposit can reach 550 million tons, with a copper grade of 0.6%. It is one of the important types of copper mines in the world. Distribution: Known porphyry copper deposits are mostly distributed in: (1) the Pacific Rim, including the South. The narrow porphyry copper belt on the margin of the North American continent, such as Lonex and Valicopa in Canada, Bingham, Butte, Morency, Erie, Santa Rita in the United States, Cananea and La Caridadela in Mexico, Cerro Colorado in Panama, Michiquile and Cerro Verde in Peru, El Abra, Chuquicamata, La Escondida, El Salvador and El Terente in Chile, etc. (3) Central Asia - Mongolia, important deposits include Karmakor in eastern Uzbekistan, Kounrad north of Lake Balkhash in Kazakhstan, Tsagansuburga south of Erdetujan Obo in central and northern Mongolia, and Alennor deposit in the east.
Sandstone-shale type: Sandstone-shale copper deposit refers to strata-bound copper deposits in sedimentary rocks of different ages. The deposits are produced in a set of sedimentary rocks or sedimentary metamorphic rocks. It is one of the main industrial types of copper mines in the world, accounting for about 30% of the world's copper reserves. The deposits are characterized by their large scale, high grade, and rich associated components, so their economic value is huge.
Massive sulfide ore: This modern deposit was first discovered on the East Pacific Ridge near 21 degrees north latitude in 1978. Although the copper and zinc grades are very high (6% copper, 29% zinc), a polymetallic massive sulfide deposit with a length of 970 meters, a width of 200 meters, a height of 35 meters, and a 25 million tons of ore volume was found on the ridge. For the first time, it met the requirements of an industrial deposit. The ore contains up to 11% copper, 0.8% zinc, and a small amount of silver (PPM), molybdenum (0.03%) and tin (0.03%).
Other types: In addition to the above types, there are vein type, natural copper type, carbonate type, skarn type, etc., which together account for only 3.6% of the world's total copper reserves, but these types may be important to different countries. For example, skarn type is a very important industrial type for my country, accounting for 28% of my country's total copper reserves. Therefore, all countries should look for high-quality deposits with the most economic value according to their specific geological environment, that is, deposits with high grade, large scale, suitable shape, and obvious ore belt boundaries. The ore is easy to handle and contains valuable by-products to ensure high profits and long-term production. The most important of these factors is high grade. The most likely source of such high-grade copper deposits will be pyrite copper deposits of volcanic origin, layered deposits, and some skarn deposits.
