摘要
在洋壳板片俯过程中,洋中脊到达海沟时通常与海沟有一定的夹角。若洋中脊在俯冲期间继续扩张就会形成板片窗构造。此外,非洋脊俯冲过程中板片撕裂或断离产生板片间隙,该间隙也称为板片窗。板片窗通常出现在活动大陆边缘,其一旦形成就会改变所在区域的局部地幔循环模式,导致在板片窗上覆板块中出现异常的地质效应,包括异常于普通俯冲带的岩浆活动、变质作用、地貌表现、流体活动以及特殊地球物理特征。板片窗特殊的地质效应控制着金、铜等特殊的金属矿产分布。综述了板片窗的形成机制、几何形态以及多种地质效应模式,以期为今后板片窗构造的研究提供借鉴。
In the process of ocean crust subduction, the ocean ridge always arrives and meets the trench in an angle. The slab window forms if the ocean ridge continues rifting. In the case, the slab will subduct without ridge, but tears or breaks-off. As the result, the slab window is formed. The slab window commonly occurs along the convergent margin. It will change the regional mantle circula- tion, and leads to such abnormal geological effects as abnormal magmatism, metamorphism, topogra- phy, fluid activity and geophysical characteristics. The specific geological effects of the slab window control the distribution of specific metallic deposits, such as gold and copper. This paper made a re- view of the formation mechanism, geometry and geological effects of the slab window for the purpose to provide helpful references.
出处
《海洋地质前沿》
2015年第12期1-10,共10页
Marine Geology Frontiers
基金
国家自然科学基金"雅浦海沟洋脊俯冲的构造作用研究"(41476046)
中国科学院前沿科学重大突破择优支持课题"深渊浅层构造特征及其与深渊底部流体活动的关系"(Y410131TP1)
关键词
板片窗
洋脊俯冲
板片撕裂
板块构造
汇聚边缘
slab window
ridge subduction
slab tearing
plate tectonics
convergent margin