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新的研究成果认为西准噶尔褶皱带超基性岩体已分出晚加里东期及中华力西期。前者侵入下古生界中,在下泥盆统底砾岩内普遍见到超基性岩砾石及碎屑。该期岩浆上侵发生同褶皱阶段,原岩浆成分相对贫铝,不利于生成铬矿床。后者侵入泥盆、石炭系中,上覆下二叠统砾岩中有超基性岩砾石及铬尖晶石。晚古生代地槽是在下古生界褶皱基底上发生和发展的,因此,岩浆侵入虽也发生在褶皱同时,但壳层厚度增大,地质环境相对稳定,加之原岩浆中富铝,有利于岩浆分异形成铬矿床,是区内重要的成(铬)矿时期。
The new research suggests that the ultra-basic rock mass in the fold belt of the West Junggar has been divided into late Caledonian and Chinese Reixi period. The former intrudes into the Lower Paleozoic and ultramafic rocks and gravels are generally seen in the Lower Devonian conglomerate. During this period, magmatic intrusion occurred in the same fold stage, and the original magma component was relatively poor in aluminum, which was not conducive to the formation of chromium deposits. The latter intruded into the Devonian and Carboniferous. The overlying Permian conglomerate contains ultrabasic rock gravel and chromium spinel. The Late Paleozoic geosynclinal occurred and developed on the lower Paleozoic fold base. Therefore, although the magma intrusion occurred in the fold at the same time, the thickness of the crust increased and the geological environment was relatively stable. In addition, the primary magma was rich in aluminum and was favorable to the magmatic fraction Chromite heterogeneous deposits, is an important area into the (chromium) ore period.