一、前言黑龙江省东部地区(图1)中生代地层较为发育,含有丰富的煤炭资源。它们以鸡西群及龙爪沟群为代表。前者以陆相含煤沉积为主,夹有少量海相沉积,后者则以海陆交互相沉积为主,夹多层火山岩。两群剖面清楚,化石丰富,是研究我国侏罗—白垩系界限的重要地区之一。同时,对两群的正确划分与对比,也将有助于煤田普查、勘探及预测。 I. INTRODUCTION The Mesozoic strata in eastern Heilongjiang Province (Fig. 1) are relatively well developed and rich in coal resources. They are represented by Jixi Group and Longzhaogou Group. The former is dominated by continental coal-bearing deposits with a small amount of marine sediments while the latter is dominated by marine-continental interaction facies sedimentation and multi-layered volcanic rocks. Two groups of clear sections, rich fossils, is to study the boundary of Jurassic - Cretaceous one of the important areas. At the same time, the correct division and comparison of the two groups will also help the coalfield survey, exploration and prediction.