Using coalfield boreholes, well logging and paleontological data carried out lower Cretaceous coal-bearing strata sequence stratigraphic framework analysis in the Jalai Nur depression, Hailar Basin, Inner Mongolia. According to regional surface of unconformi⁃ty, incised valley channel sand body scouring surface and paleontological assemblage mutation surface has divided the lower Creta⁃ceous coal-bearing strata into two third-order sequences, established isochronal sequence stratigraphic framework and studied sedi⁃mentary facies and coal accumulation characteristics. The result has shown: Sequence I has perfectly developed 3 systems tracts in southern depression, only upper highstand systems tract (HST) developed in northern part that is a thick shallow lake shore mudstone deposit. Sequence II developed 3 systems tracts, completely preserved, lowstand systems tract (LST) developed mainly thick distribu⁃tary channel sandstone;lacustrine transgressive systems tract (LTST) developed mainly delta plain, deltaic interdistributory bay and riv⁃er mouth bar deposits; highstand systems tract (HST) developed mainly thick lake shore siltstone, mudstone and coal seam deposits. Coal accumulation environment in Jalai Nur depression is mainly low-lying areas between delta plain and delta lobe, coal-rich zones are situated in western and northeastern parts of the depression, coal seam thickness can be 30m as high.%利用煤田钻孔、测井及古生物等资料对内蒙古海拉尔盆地扎赉诺尔凹陷下白垩统含煤岩系层序地层格架进行分析。根据区域不整合面，下切谷河道砂体冲刷面及古生物组合突变面把研究区下白垩统含煤岩系分为两个三级层序，并建立等时层序地层格架，对沉积相及聚煤特征进行了研究。结果表明：层序I在凹陷南部3个体系域发育完整，在北部仅发育上部的高水位体系域，为厚层滨浅湖泥岩沉积。层序II的3个体系域发育、保存齐全，低水位体系域主要发育厚层分流河道砂岩；湖侵体系域主要发育三角洲平原、三角洲分流间湾和河口坝等沉积；高水位体系域主要发育厚层的滨湖粉砂岩、泥岩和煤层沉积；扎赉诺尔凹陷的聚煤环境主要是三角洲平原及三角洲朵叶体之间的低洼地带，富煤带主要位于凹陷西部和东北部地区，煤层单层厚度可达30m。
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