青岛近海古河道断面特征与古地理变迁关系研究

通过对青岛近海1 561 km的高分辨率浅地层测量剖面解译，在多条剖面中发现研究区存在多期发育的古河道，虽然保存较完整的地层不多，但大部分河流亚相地层被保存。测年资料表明，这些河流多形成在37 000～11 000 a之间，河流床底最大埋深（海底起算）约－32 m，一般在－20～－28 m，最大单个河面宽约1 500 m。根据现在所见河道的轮廓形态，可分为六种类型:即发育有滩心洲的河道、平底河道、不对称河道、连续多期发育的河道、窄陡型河道和对称型河道。并对河流的形成机理和古地理特征作了初步分析。

Relationship Between River Cross Section Characters and Change of Ancient Geography of Offshore in Qingdao Bay

Based on high resolution seismic profiles surface of offshore 1 561 km nearby Qingdao, we discovered that there were multi stage developed ancient river ways in this area and river sedimentary system was not well preserved in many stratums in the most of them only some of the river subfacies stratums are preserved. The character of river cross section to the east of 120°30′is relatively well preserved. The data of age measurement showed that these rivers were mostly formed 37 000～11 000 years ago, that the largest burial depth(from the bottom of modern sea to river bottom) of riverbed was about 32m and the usual burial depth was between 20～28 m and that the widest part of the river orientation was approximately 1 500 m. The river section can be divided into 6 types according to the present visible figures, which are watercourse developed with channel bar, flat base continuous multi stage developed, steep narrow, asymmetric. This paper also includes the general analysis of formation mechanism of rivers and ancient geography environment.