元古代Mporokoso群底部的含金砂岩和砾岩是在树枝状河系中沉积的。碎屑砂物质有石英、绢云母和赤铁矿,而砾石为脉石英、燧石、酸性火山岩、硅化变质沉积岩和碧玉铁质岩。河流沉积物的岩石学研究指出,氧化硅和在较小程度上的氧化铁曾在河系范围内流动。在岩石中发育有碧玉铁质岩砾石、玉髓球粒和球皱晶,大量的石英细脉,硅化火山碎屑。碎屑赤铁矿形成岩浆成因磁铁矿假晶。 Gold-bearing sandstones and conglomerates at the base of the Paleoproterozoic Mporokoso group were deposited in dendritic river systems. Chromite materials are quartz, sericite and hematite, while gravel is vein quartz, chert, acidic volcanic rocks, silicified metasedimentary rocks, and jasperite. Petrological studies of river sediments indicate that silica and, to a lesser extent, iron oxide have flowed in the river system. In the rock are developed jasper iron rock gravel, cornelian pellets and ball crumbs, a large number of quartz veins, silicified volcanic debris. Debris Hematite Formation Magnetism Magnetite Fake.