摘要
以秦皇岛柳江盆地新元古界为研究对象,重点研究长龙山组沉积特征、沉积相及古水流。通过野外踏勘、大比例尺剖面测量、岩层结构构造描述、交错层理及面理的测量分析,表明秦皇岛柳江盆地新元古界长龙山组发育多套粗粒石英砂岩、中粒石英砂岩、细粒石英砂岩、粉砂岩、泥岩、页岩、灰岩旋回,反映出长龙山组时期到景儿峪组时期曾发生多次海进海退事件。得到秦皇岛柳江盆地长龙山组-景儿峪组两条剖面(张岩子剖面、李庄北剖面)剖面测量结果,显示长龙山组以砂岩为主,分选较好,磨圆度较高。通过室内薄片观察,粒度分析结果显示秦皇岛柳江盆地长龙山组时期主要发育海相沉积,且底部有河流相参与,砂岩粒度主要分为海滩相及浅水陆棚相两个相带。根据层理产状玫瑰花图推断长龙山组时期古水流方向为135°左右。
The subject of this study is Neoproterozoic Sedimentary Characteristics in Liujiang Basin in Qinhuangdao.The key study is the Depositional feature,Sedimentary facies and Paleocurrent.Through field reconnaissance,large scale profile measurement,description of rock structure,staggered bedding and measurement analysis of Qinhuangdao Liujiang Basin Neoproterozoic Changlongshan group and Jingeryu formation mainly developed multiple sets of coarse-grained quartz sandstone,Medium grained quartz sandstone,Fine-grained quartz sandstone,Powder sandstone,shale and limestone cycling,reflecting the changlongshan formation period to Jingeryu formation period occurred repeatedly transgression and regression.The field profile measurement were measured and Liujiang Basin in Qinhuangdao of Changlongshan formation of two section-(ZhangYanzi profile,Lizhuangbei profile) profile measurements revealed the Changlongshan formation is sandstone,better sorting and grinding roundness is higher.Through indoor slice observation,grain size analysis results show that marine sediments at the bottom of the main development of Qinhuangdao Liujiang Basin of Changlongshan formation period is coherent and river deposition,sandstone grain size is divided for beach facies and shallow shelf two facies belts.According to the stratification that rose diagram of Changlongshan formation period paleocurrent direction is about 135 degrees.
出处
《中山大学研究生学刊(自然科学与医学版)》
2015年第3期56-64,共9页
Journal of the Graduates Sun YAT-SEN University(Natural Sciences.Medicine)
关键词
新元古界
沉积特征
沉积相
古水流
Neoproterozoic
Sedimentary characteristics
Sedimentary facies
Palaeocurre