冀东太古宙高级变质区深部构造相韧性变形条带的成因及演化

GENESIS AND EVOLUTION OF THE DUCTILE DEFORMATIONAL BANDS IN DEEP TECTONIC FACIES IN THE ARCHAEAN HIGH GRADE METAMORPHIC AREA, EAST HEBEI

冀东太古宙片麻岩中的条带状构造极其发育,经研究认为它们是深部构造相韧性变形带的主要结构构造特征。按成因类型将其划分为变余沉积条带、变质分异条带、复合条带和构造置换条带等。并研究了不同成因条带的组成特征、形成演化及识别标志。这一研究对认识下部地壳构造特征具有重要意义。

The banded structures in the Archaean gneiss area in East Hebei are well developed, They are the chief structural features of the ductile deformational bands in the deep tectonic structure facies (corresponding to granulite facies). They are divided, according to their genesis, into four major types, i. e. sedimentary band, metamorphic differentiated band (further subdividedinto four types, mechanical differentiated band, chemical differentiated band, partial melting band and emplacing band of rock body in solid-state), composite band and structural transposition band. Meanwhile,a study on constituting characteristics, formation evolution, and distinguishing marks of different genetic band is made, having a great significance in the research on characteristics of lower crustal structure.