江西白垩纪—新近纪陆相红色盆地的盆缘类型划分与盆地充填样式

Basin-margin types and basin-fill types of Cretaceous-Neogeneterrestrial red basins in Jiangxi

根据在江西白垩纪—新近纪陆相红盆地中1∶50000地质填图对盆地的盆缘类型和盆地充填样式研究的新认识,以及陆相红盆地的形成、发展机制与盆地边缘岩石的成生性质,将盆缘划分为基底盆缘和新生盆缘2类;又依据盆缘的原始自然坡度和形态特征划分为缓坡型、折坡型、陡坡型(或断坡型)和新缓坡型、新折坡型、新陡坡型等6型。根据陆相红盆地中不同构造期(幕)不同沉积环境沉积的沉积体的空间展布特征及其各种有序叠置组合形式,厘定了辫状河—湖三角洲—浅湖型、冲积扇—辫状河—湖三角洲—浅湖型、冲积扇—浅湖型、近岸水下扇—浅湖型、冲积扇—辫状河型和河流—沼泽(湿地)型等6种盆地充填样式。

During 1∶50000 regional geological mapping of Cretaceous-Neogene terrestrial red basins in Jiangxi Province, the authors got some new ideas about the study of basin-margin types and basin-fill types. According to these new ideas, coupled with the formation and development mechanism of the terrestrial red basins and the genetic properties of basin-margin rocks, basin margins may be divided into basement basin margins and rebirth basin margins, and according to the primary physical grade and morphological features of basin margins, six types may be further distinguished; they are the gentle slope type, slope break type, steep slope type (or fault ramp type), rebirth gentle slope type, rebirth slope break type and rebirth steep slope type. Finally, on the basis of the spatial distribution characteristics of sedimentary bodies and their various orderly superposition patterns in different tectonic stages (phases) and different sedimentary environments, six types of basin fill are identified; they are the braided river-lake delta-shallow lake type, alluvial fan-braided river-lake delta-shallow lake type, alluvial fan-shallow lake type, near-lake underwater fan-shallow lake type, alluvial fan-braided river type and river-marsh (wetland) type.