造山带古地理和盆地分析基础 :　露头的复原与复位——以前龙门山中北段泥盆系为例

DETERMINATION OF DEPOSITIONAL POSITION OF OROGENIC BELT STRATA IN PALEOGEOGRAPHY AND BASIN ANALYSIS

造山带地层露头非原地性广为标识，但其复原与复位并未引起重视。以扬子地台西缘前龙门山中北段泥盆系为例，进行露头展平宽度、剥蚀宽度复原，对露头原始位置进行尝试性复位，并讨论的存在问题和可能的发展方向。

Nothing has been done for the determination of depositional position of orogenic belt strata although it is well know that they are thrusted and slided away from their host basin. In the paper, the author proposes that there are four steps to determine the primitive postion for nappes by researching Devonian in the middle northern Fore Longmenshan area. The first step is to cut and to measure the cross section along the axis of fold, the second is to calculate level width of exposure on a formula, the third is to determinate the shoreline by calculating the eroded width, and the fourth is reversely to drive the leveled exposure to host strata on the basis of thrusting and sliding direction and distance of the nappe. Furthermore, some problems and developments of this subject are discussed in the end of the paper.