小兴安岭与松辽盆地新生代耦合关系

Coupling relationship between Lesser Khingan Range and Songliao Basin in Cenozoic

通过遥感影像判读、野外高精度GPS定位和数字高程模型分析,查明小兴安岭层状地貌的类型、级数、高程、组成物质和空间展布情况。研究结果表明,新生代以来小兴安岭形成了2级夷平面和5级河流阶地。采用线性函数和二次函数两种统计模型对逊克、嘉荫地区的新生代层状地貌单元相对高度与松辽盆地相应时期沉积物厚度作回归分析,统计模型回归平方和与总离差平方和的比值R^2=0. 944～0. 968,回归方程的整体拟合度很高,该结果显示小兴安岭新生代各个阶段的隆升幅度与松辽盆地的沉降幅度呈正相关关系。新生代期间小兴安岭隆升幅度为449 m,其中第四纪以来的隆升幅度为250 m。第四纪期间小兴安岭平均隆升速率为102. 88 mm/ka。小兴安岭间歇性隆升与松辽盆地间歇性下降是同一构造背景下盆山耦合的两种不同表现形式。

On the basis of remote sensing image interpretation,high-precision GPS positioning in the field and digital elevation model analysis,the types,quantities,altitudes,constituents and spatial distributions of stratiform landforms in the Lesser Khingan Range are worked out. The results show that second-order planation surfaces and fifth-order river terraces have been developed in the Lesser Khingan Range since Cenozoic. Taking linear and quadratic functions as statistical models,the regression analysis on the relative heights of Cenozoic stratiform landforms at Xunke and Jiayin and the thicknesses of simultaneous deposits in Songliao Basin have been carried out. The ratios of regression square sums to total deviation square sums(R^2) are between 0. 944 and 0. 968,showing that the fitting degrees of the regression equations are very high and the uplift range of the Lesser Khingan Range in every stage during Cenozoic is in positive correlation with the subsiding amplitude of the Songliao Basin. The uplift range of the Lesser Khingan Range is 449 m during Cenozoic,and is 250 m in Quaternary. The average uplift rate of the Lesser Khingan Range is 102. 88 mm/ka in Quaternary. The intermittent uplifting of the Lesser Khingan Range and the intermittent subsidence of the Songliao Basin are the two different manifestations of basin-range coupling at the same tectonic background.