秦岭—巴山地区成矿背景和成矿作用的新进展

NEW ADVANCES IN THE STUDY OF ORE-FORMING BACHGROUN AND MINERALIZAATION IN QINLING-BASHAN REGION

“八五”—“九五”期间秦岭的多项研究中 ,主要取得以下新进展 :1 创立了抽拉—逆冲岩片构造新理论 ,丰富和发展了岩石圈板块或壳块运动方式的多样性。 2 发现了东西向的秦岭造山带从显生宙以来有南北向的隆升带和沉积盆地 ,特别是太白、宝鸡—佛坪—汉南隆升带的发现 ,将从根本上改变秦岭乃至中国中东部构造格架的认识。 3 南北向沉积盆地转变为东西向造山带的Ⅱ型造山带 ,深部构造岩片抽拉 -逆冲推覆在中 (新 )生代陆相沉积盆地之上所形成的Ⅲ型造山带 ,为地壳表层增添了两种新型的造山带。 4 首次提出秦岭造山带中存在三类沉积盆地 ,三种盆—山转换 ,三个发展阶段及三种型式 (Ⅰ、Ⅱ、Ⅲ )的造山带 ,这在国内外均属首创。 5 重新厘定商丹带、勉略带和二郎坪带的构造属性、形成时代 ,首次提出秦岭受三种体制 ,四个发展阶段的新观点 ,受抽拉构造形成的陆内造山带是秦岭最重要的划时代发展阶段。 6 最先提出立交桥式结构观点。 7 发现了一批前震旦系变质地层结晶岩系、重新厘定了一些地层的时代 ,特别是西秦岭、西成铅锌矿田中元古界地层的发现和超大型厂坝矿床产于其中 ,有重大的理论和实际意义。 8 提出准浊流态流体的新概念。 9 创立了在统一地质

During the 'Eighth Five' and 'Ninth Five', following new advances have been made in the geological study in Qinling Bashan Region: (1) Created the new theory, i.e., drawing out thrust sheet tectonics, which enriched and developed the diversity of the movement of lithosphere plates or crust blocks. (2) Discovered north south trending uplift zones and sedimentary basins in the east west trending Qinling. These discoveries, especially, those of Taibai uplift zone and Baoji Foping Hannan uplift zone, will change the cognition of the tectonic framework of Qinling, even China. (3) Identified type II orogenic belt and type III orogenic belt. The former is a east-west trending one that formed from north south extending sedimentary basin, and the later is such that formed by drawing out and thrusting of deep tectonic sheets over Meso or Cenozoic continental sedimentary basins. Both of them are new types of orgenic belts that have never been reported before. (4) Recognized three types of sedimentary basins, three models of basin mountain transformation, three development stages and three types of orogenic belts (types II, III and I) for the first time. (5) Collated and stipulated the tectonic nature and forming time of Shangdan tectonic belt and Mianxian Lueyang tectonic belt anew. For the first time, it is considered that the development of Qinling orogenic belt is controlled by three tectonic systems and four evolution stages and that the intracontinental orogenic belt formed by drawing out tectonism was the most important development stage. (6) First advanced the cross bridge shaped structure of Qinling. (7) Discovered some Pre Sinian metamorphic strata, collated and stipulated the time of some strata. It should be addressed that the discovery of Mid Proterozoic strata in the Xicheng zinc lead ore field of west Qinling where the ultra large Changba ore field occurs, have both theoretical and practical significance. (8) Advanced the new concept of para turbiditic fluid. (9) Created the ore controlling theory of multiple tectonic sheets and tectonic mineralizing system determined by universal geological mineralizing field. For the first time, we proposed that there are three types of universal geological mineralizing field, three tectonic-mineralizing systems, three mineralizing models and three models for regional ore prospecting. (10) First put forward the viewpoint that the enrichment locations of ultra-large ore deposits and the formation of ultra large ore deposits are controlled by sheath folds. (11) Got new understandings of the genesis of some ore deposits, especially those of Xicheng zinc lead deposit and Zhangla gold ore deposit, which will play a directive role in ore prospecting. (12) Determined three prospective lands of grade 3, thirteen of grade 4 and twenty seven of grade-5 (which may be subdivided into 11 prospective lands of grade A, 9 of grade B and 7 of grade C). Furthermore, we pointed out ten suggested regions for searching large ore deposits and Mulongtao type gold deposit.