黑龙江黑河西北洪业家推覆剪切构造带地质特征及其意义

黑龙江黑河西北洪业家推覆剪切构造带呈EW向展布于落马湖中间隆起带南侧与罕达气古生代褶皱带北结合部位,据变形强弱划分了北、中、南三个强变形带.宏微观构造观察表明,其剪切运动方向为自北向南的推覆剪切.强应变带内三件不同时代岩石的K-Ar同位素年龄为155~158Ma,表明推覆剪切时代为中侏罗世末.该构造带的发现支持了古亚洲构造域对东北微陆块区的影响一直延续到中侏罗世的观点. 

GEOLOGICAL CHARACTERISTICS OF THE HONGYEJIA THRUST SHEAR ZONE NORTHWEST OF HEIHE IN THE HEILONGJIANG RIVER VALLEY AND ITS SIGNIFICANCE

The Hongyejia thrust shear zone northwest of Heihe in the Heilongjiang River valley extends in an E-W direction in the junction between the southern side of the Luomahu median uplift and the northern margin of the Paleozoic Handaqi fold belt.According to the degree of deformation the north,central and south strong deformation belts may be distinguished.Macroscopic observations indicate that the sense of shear movement is south-directed.Three samples of rocks of different ages in the strong strain belts give K-Ar ages of 155 to 158 Ma,suggesting that the age of the thrust shear is terminal Middle Jurassic.The discovery of this tectonic zone supports the view that the influence of the Paleo-Asiatic tectonic domain on the Northeast China microblock persisted till the Middle Jurassic.