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近年来,通过对西北地区地槽褶皱带深入研究结果表明,具成铬远景的超基性岩带,赋存于特定的构造部位,即沿褶皱带与基底隆起(地槽中间隆起带或地块)带接合处的深断裂带分布。这里活动性最强,一般都是地槽向洋迁移起步地带,断裂生成早,且继承性长期活动,曾多期次下切地幔导致大量基性、超基性岩浆侵入和分异作用。因而沿这类断裂带形成明显的基性、超基性岩带。岩带中的岩体数量多,总面积常为全区诸岩带之冠。伴生的基性侵入体发育程度亦居首位。岩带总体基性度偏高,由多岩相组成,铬铁矿化较普遍,产有工业矿床。例如,西准噶尔华力西中期优地槽褶皱带西南部,由南而北依次出现拉巴—达拉布特弧形超基性岩带,玛依勒弧形超基性岩带及塔斯特弧形超基性“岩带”。其中以拉巴—达拉
In recent years, through deep research on the geosynclinal fold belt in the northwestern China, the results show that the ultrabasic rock belt with chromic prospect exists in a specific tectonic part, ie along the fold belt and basement uplift Block) Deep fracture distribution with joints. The most active here, are generally to the migration of the trench to the start of the zone, the fracture generated early, and long-term succession activities, has undergone many times cut the mantle caused a large number of basic, ultrabasic magmatic intrusion and differentiation. Thus along these types of faults to form a clear basic, ultrabasic rock belt. The number of rock mass in the rock belt is large, and the total area is often the highest among the rock belts in the whole area. Accompanying basic invasive body development also ranks first. The rock mass is generally of high basicity and is composed of multi-facies facies, and chromite mineralization is more common, with industrial deposits. For example, the western Junggar Walsh western Mesozoic trough fold belt in the southwestern region, from south to north there are successively Laba-Dalbott arcuate ultramafic rock belt, Ma Yilu arc-shaped ultramafic rocks and Tarst Arc-shaped ultra-basic “rock belt.” Among them, Laba-Dala