摘要
通过对胶辽吉地区古元古代裂谷带的深入研究，提出了伸展构造环境下中深部地壳花岗质岩浆侵位的一种模式，即花岗质岩浆沿基底与盖层之间的拆离滑脱带多次贯入，形成岩席，之后随着地壳拉伸（或伸展）作用，这些岩席逐渐远离侵位中心，发生侧向迁移。这种大陆壳内中深部花岗质岩浆的侵位和地壳的侧向伸展的模式，与有些学者提出的大洋中脊玄武质岩浆的侵位和洋壳扩张的模式是基本相似的。这一模式也是大陆地壳快速生长加厚的一种有效机制。由于花岗质岩浆的上涌引起上覆盖层因重力失稳形成一系列顺层滑脱构造组合。
Based on study of Palaeoproterozoic palaeo rift of Jiao Liao Ji area,an emplacement model of granitoid magmas in mid and deep crust under extension is proposed here, i.e. multiple injected granitoid magmas emplaces along detachment surface or cover/basement interface and migrates gradually far away from emplacement center. The model of granitoid magmas emplacement and crustal extension in mid or deep crust likes that of mid ocean ridge mafic magmas emplacement and oceanic spreading exactly. It is perhaps an efficient mechanism of rapid crustal growth. A series of bedding slide structures (or bedding delamination structural series) are derived from gravitational instability of overlayered sedimendary cover coeval with granitoid magmas upwelling. We call structural assemblage of cover, basement or granite (core) and contact plane between cover and core as uplift bedding delamination structural series (UBDS).
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
1997年第2期189-202,共14页
Acta Petrologica Sinica
关键词
花岗岩
侵位模式
隆滑构造
古元古代
Middle and deep crust
Granite
Emplacement model
Uplift bedding delamination structure
