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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。
There has always been a divergent view of the Pergamidia era: most consider it to be Norfolk’s typical fossil, but its age is thought to be from the period of Carnick to Norlich, and Pergamidia’s fossil assemblage appears in Norrick . A large number of bivalve fossils have been produced in the profile of the Namlehai-State stock farm in the Changtai region of western Sichuan, including the previously reported Halobia yunnanensis-Halobia pluriradiata (Hy-Hp combination) and this The new fossil assemblage of Pergamidia genus collected during the observation of the Narenhai section consists of Pergamidia eumenea, Pergamidia attalea, Pergamidia timorensis and Pergamidiaeumenea hoqingensis. The horizons of the new fossil assemblage in this section lie at the bottom of the Hy-Hp assemblage, and the data confirm that the Hy-Hp assemblage is the mid- and late-typical fossil assemblage of Carnick. In the Perga-midia period, the delineation of Perga-midia period is Carnick-Noril period. The assemblage of bivalve fossils, mainly of Pergamidia genus, may appear in Norick period and also in Carnike period. Pergamidia gathers, thrives in the environment of the end of acidic volcanic activity and begins to spread to the environment from the Leningrad Sea.