中国西北部造山带中几个古生代俯冲增生楔的识别与确认

中国西北部涉及古亚洲和特提斯两大构造域,造山带结构复杂,成矿地质条件优越。为推进地质找矿突破行动计划,中国地质调查局在各成矿(造山)带部署了一批1∶5万、1∶25万区域地质调查与基础地质综合研究项目,取得了一批新发现、新进展,有效提升了对各成矿带成矿地质条件的认知程度,尤其是在阿尔泰南缘、南天山、南昆仑等地识别并确认出规模可观的、成矿作用优越的板块俯冲增生楔,是造山带中的增生造山亚带,是寻找斑岩型铜、构造蚀变岩型金及多金属矿的最有利区带。"增生造山带"的构造、岩浆活动及空间展布等的确认,为地质找矿突破提供了强有力的技术支撑。

Recognition and confirmation of paleozoic accretionary wedges in Subducted orogenic zone,Northwest China

The northwest China is located at the superimposed tectonic domain of the Tethyan belt and the Paleo-Asian Ocean. This superimposed tectonic setting and composite structure result in favorable metallogenic conditions of polymetallic ore deposits. In order to promote the prospecting breakthrough and strategic action, the China Geological Survey deployed a number of 1∶50 000, 1∶250 000 regional geological survey and basic geological studying projects in northwest China. These projects achieve a number of discoveries and progress which are helpful to understand the metallogenic conditions. Considerable scale subduction-accretionary wedges with favorable metallogenic conditions are recognized and confirmed, especially in the southern margin of Altai region, the South Tianshan Mountains and South Kunlun. These accretionary wedges are subzone of orogenic zone, which are the most favorable areas for porphyry copper deposits and fault-altered rock type gold polymetallic deposits. Further research on the structure, magmatic activity and spatial distribution of the accretion orogenic zone will provide strong technical support for prospecting breakthrough.