河口凹陷为济阳坳陷的一个次级构造,位于黄河入海口附近。由地层等厚图,构造图及重力图分析得知,在河口凹陷接受第三系沙河街组沙三段沉积时,凹陷的南、西、北三面均表现为高的地势,分别为陈家庄、义和庄和埕子口凸起;东边则是孤岛低隆起。凹陷内部的 The estuary depression is a secondary structure of the Jiyang Depression, located near the mouth of the Yellow River. Based on the isopachograms, tectonic maps and gravimetric analysis of the strata, it is known that when the estuary depression receives the deposition of the third member of Shahejie Formation in the third member of the Shahejie Formation, the south, west and north sides of the depression show high terrain, namely Chenjiazhuang, Yihezhuang and Jizi mouth raised; the east is the island lows. Inside the depression