Pergamidia在川西昌台纳楞海三叠系的发现及时代意义  

THE DISCOVERY OF LATE TRIASSIC PERGAMIDIA IN NALENGHAI,CHANGTAI AREA OF WESTERN SICHUAN AND ITS BIOSTRATIGRAPHIC SIGNIFICANCE

作　　者：庞艳春[1] 王新利[2] 王晓宇[1] 

机构地区：[1]成都理工大学沉积地质研究院,四川成都610059 [2]鑫达金银开发中心,北京100054

出　　处：《地层学杂志》2010年第3期298-302,共5页Journal of Stratigraphy

基　　金：国家自然科学基金项目(No.40472013);成都理工大学青年基金(No.2006QJ26)联合资助

摘　　要：对于Pergamidia的时代,一直存在不同的观点:多数人认为它是诺利克期的典型化石,但也有认为其时代为卡尼克期至诺利克期,以Pergamidia为主的化石组合则出现在诺利克期。在四川西部昌台地区的纳楞海—国营种畜场剖面中,产出了大量的双壳类化石,包括前人发现的双壳分子组合Halobia yunnanensis-Halobia pluriradiata(Hy-Hp组合)及本次观测纳楞海剖面时采集的以Pergamidia属的分子为主的新化石组合,由Pergamidia eumenea,Pergamidia attalea,Pergamidia timorensis,Pergamidiaeumenea hoqingensis等组成。新化石组合在该剖面中的层位位于Hy-Hp组合的底部,资料证实Hy-Hp组合为卡尼克中、晚期典型化石组合。区域上的Perga-midia时代延限为卡尼克期—诺利克期,以Pergamidia属为主的双壳类化石组合面貌既可以出现于诺利克期也可出现在卡尼克期;川西昌台地区的Pergamidia在具有酸性火山活动末期的环境中聚集、繁盛,并从纳楞海开始向周围环境扩散。The stratigraphic range of Pergamidia is uncertain. Some paleontologists believe that Pergamidia occurs in the Norian Stage,whereas others think that Pergamidia ranges from the Carnian to the Norian Stage. A large number of bivalve fossils have been found at the Nalenghai section,Changtai area western Sichuan,including members of the bivalve Halobia yunnanensis Reed-Halobia pluriradiata Reed （Hy-Hp） assemblage described by previous investigators,as well as new bivalve fossil.The new fossil include Pergamidia eumenea Bittner,Pergamidia attalea Bittner,Pergamidia timorensis Krumbeck,Pergamidia eumenea hoqingensis J. Chen and others. The new fossils co-occur with the Hy-Hp assemblage in the Nalenghai section. Previous investigators have established that the Hy-Hp assemblage is of middle to late Carnian Stage.Thus,Pergamidia probably ranges from the Carnian to the Norian Stage. In the Changtai area of western Sichuan,Pergamidia thrived after felsic volcanic eruptions and spread from the Na-lenghai to the other regions.

关 键 词：Pergamidia 时代 三叠纪 纳楞海 昌台地区 四川 

分 类 号：P534.51[天文地球—古生物学与地层学]