摘要
尽管地壳最上部的构造、岩性和地球化学条件控制着内生金属矿床的就位,然而最大量金属富集的地点和空间分布却常被幔根构造间断面(mantlerootedstructuraldiscontinuity)所控制。这些构造间断面延长几百到几千km,这表明它们是在比地壳最上部更为均质环境的应力分布下产生的。这些构造间断面与其它的近于垂直的深部构造的交切面界定了主要的岩石圈块体并提供了热、岩浆和成矿流体上升的通道。金属趋向于富集在这些块体的角上,以及构造间断面与板块边缘、裂谷构造或造山带的穿插部位。对上述组合型式的幔根构造间断面和它们在地表地质投影的识别,可确定金属聚集有较大潜力的靶区。文章还提供了来自不同地质环境的实例。
Although structural, lithological and geochemical conditions in the uppermost crust control the emplacement of endogenic ore deposits, the location and space distribution of the largest metal concentrations is at the same time usually controlled by patterns of mantle rooted structural discontinuities. These discontinuities extend for hundreds or thousands of kilometers, indicating they originated under stress distribution in a more homogeneous environment than that of the uppermost crust. Intersections of these discontinuities with other near vertical deep seated structures define major lithospheric blocks and provide channelways for the ascent of heat, magmas and ore forming fluids. Metals tend to concentrate near the corners of the blocks and in places where the discontinuities penetrate plate margins, rift structures or orogenic belts. Recognition of such patterns of mantle rooted structural discontinuities and their projection over the surface geology allows to define target areas with a higher potential for concentration of metals. Examples from different geological environments are presented.
出处
《地学前缘》
EI
CAS
CSCD
1999年第1期29-53,共25页
Earth Science Frontiers
基金
IGCP项目
关键词
幔根构造间断面
矿床成矿
成矿控制
地壳破裂
structural controls of ore deposits, stress distribution, mantle rooted structural discontinuities