【作者】 郝诒纯； 万晓樵；

【Author】 Hao Yichun Wan Xiaoqiao (Beijing Graduate School of Wuhan College of Geology)

【机构】 武汉地质学院北京研究生部；

【摘要】 <正>西藏南部海相白垩、第三系目前主要发现于岗巴、定日、仲巴等地。1980—1981年,地质部高原地质调查大队第十一分队在岗巴、定日一带做了较详细的地层研究。岗巴地区的地层情况已由作者另文发表,本文在室内古生物研究工作的基础上对定日地区海相白垩、第三系的发育情况提出一些看法。更多还原

【Abstract】 The marine Cretaceous and Tertiary strata of Tingri (定日) occur mostly in Gongza (贡札),Chagnag (查那),Duimi(堆米) and Entong (恩同) districts. They were once believed as of Eocene in age,overlying the Zongpu Forma- tion (宗浦群),and named as Zhepure Group (遮普惹群).In our researching work,not only the larger foraminifers in the upper limestone are further identified,but also abundant planktonic foraminifers are discovered.They are Rotalipora,Globotruncana,Praeglobotruncana,Hedbergella,Ticinella,Globiger- inelloides,etc..This has provided a powerful evidence for the existence and dating of the strata. The stratigraphic development of Gongza section is similar to that of the Cretaceous and Tertiary strata of Gangba (岗巴) region,and composed of the Dongshan Formation (东山组),Chaqiela Formation (察且拉组),Leng- qingre Formation (冷青热组),Xiawuchubo Formation (夏吾除波组),Jiubao Formation (旧堡组),Jidula Formation (基堵拉组) of Cretaceous and Zongpu Formation (宗浦群) of Tertiary.The foraminifer assemblages in each forma- tion compare directely with those of Gangba region. It is concluded that (1) Tingri and Gangba regions are a part of the same stratigraphic area.Marine Cretaceous and Tertiary strata of both regi- ons develop correspondently.The features of foraminifer assemblages are alike with the same stratigtaphic age.The age previously determined for the Zhepure Group does not hold water.(2) Abundant planktonic foraminifer fossils are found in Cretaceous of both regions,with their evolutional process identical and with obvious character of development by stages.The Cretace- ous planktonic foraminifer zones of Southern Xizang might be set up after more detailed study;(3) The youngest marine strata of both regions are constrained in Lutetian of Middle Eocene,and the youngest ones of Zhongba (仲巴) region should be no younger than Middle Eocene too.Therefore,it is reliable that the ingression of Southern Xizang came to an end in Middle Eocene.更多还原