松辽盆地三肇地区泉头组三段上部介形类化石的指相意义  

ENVIRONMENTAL SIGNIFICANCE OF OSTRACOD FOSSILS FROM UPPER PART OF 3RD MEMBER OF QUANTOU FORMATION,SANZHAO AREA, SONGLIAO BASIN

作　　者：张智礼[1] 杨湘宁[1] 蒙启安[2] 曹立君[3] 张莹[2] 

机构地区：[1]南京大学地球科学系,南京210093 [2]大庆油田有限责任公司勘探开发研究院,黑龙江省大庆163712 [3]大庆石油管理局农工商联合公司,黑龙江省大庆163458

出　　处：《古生物学报》2005年第2期260-266,共7页Acta Palaeontologica Sinica

摘　　要：松辽盆地三肇地区白垩系下统泉头组三段上部(杨三组—杨一组)以大套的紫红、红色砂、泥岩沉积为主,在紫红色泥岩中含有较丰富、完整的介形类及其它门类化石。以往认为,这套以红色为基调的地层属河流相沉积。对其中介形类等化石的古生态、埋藏特征及丰度变化的研究表明,该地层的沉积环境应为浅水湖泊环境,而非河流等水上环境。湖相沉积自杨三组就已存在,向上分布范围不断扩大,反映了湖泊水域面积呈现逐渐扩大的趋势。The upper part of 3rd member of the Early Cretaceous Quantou Formation is primarily composed of purple and red sandstones and mudstones in Sanzhao area, Songliao Basin. Previous studies suggested that the red mudstones, in which abundant and well-preserved ostracods and other fossils have been found, could be considered as fluvial deposits. Based on results of a comprehensive analysis of the abundance variation of ostracod species, their ecologic and taphonomic features, we interpret the mudstones in the upper part of 3rd member of the Quantou Formation was formed in a shallow lacustrine environment. Regional data has further suggested that the lacustrine environment had been existed in the early period and gradually expanding when the oil-generating Yang-3 Formation was deposited.

关 键 词：三肇地区 松辽盆地 泉头组 介形类化石 指相意义 河流相沉积 红色泥岩 埋藏特征 湖泊环境 沉积环境 湖相沉积 分布范围 水域面积 白垩系 古生态 地层 丰度 

分 类 号：Q911.2[天文地球—古生物学与地层学]