Metallic and non-metallic deposit types formed in sedimentary and weathering environments are reviewed. The deposits formed in sedimentary environment are divided into those formed by 1) mechanical deposition, 2) chemical deposition and 3) biogenic deposition. The deposits formed by mechanical deposition further subdivided into jewel stone deposits, quartz-pebble conglomerate deposits, heavy sand deposits, silica sand deposits and clay deposits. The deposits formed by chemical deposition include caliche, brine, evaporite, carbonate deposits, bedded manganese deposits, banded iron formation and manganese nodule/crust. The deposits formed by biogenic deposition include limonite, phosphate, limestone, diatomite and chert. The phosphate deposits are quite variable, including guano, shallow-marine sediments and deep-marine mud.
The deposits formed in weathering environment are separated into residual deposits in a broad sense and deposits formed by the weathering of specific host rocks and minerals. The broad sense residual deposits are classified into 1） the residual deposits in a narrow sense in which minerals are derived directly from the host rocks, and 2） those in which minerals are formed in supergene weathering environment, such as iron and manganese deposits, bauxite deposits and kaolinite deposits. The deposits formed by weathering of specific host rocks and minerals include weathered carbonatite deposits, laterite nickel deposits from mafic-ultra mafic rocks, ion-adsorption deposits from granite, syenite and felsic volcanic rocks, kaolinite deposits from anorthothite, vermiculite deposits from biotite- and chlorite-bearing rocks, and supergene and/or exotic copper deposits from hypogene sulfide copper orebodies.
However, it is very common that these deposits in these environments formed by overprinting of multiple different processes, and exact appraisal of the involved processes will help the exploration and evaluation of the mineral resources.
