福建永安丰海晚二叠世—早三叠世早期菊石动物群及地层意义  

LATE PERMIAN AND EARLY EARLY TRIASSIC AMMONOID FAUNA OF FENGHAI, YONG'AN, FUJIAN AND THEIR STRATIGRAPHIC SIGNIFICANCE

作　　者：王明倩[1] 

机构地区：[1]福州大学地质采矿工程系

出　　处：《古生物学报》1990年第6期755-773,799-802,共19页Acta Palaeontologica Sinica

基　　金：国家自然科学基金

摘　　要：一、前言福建中部和西部处于东特提斯海域的东缘,晚二叠世晚期属于华夏陆地西侧局限海近滨含菊石粉砂质、泥质沉积区(周祖仁,1985)。二叠系与三叠系连续,由晚二叠世粉砂质、泥质沉积过渡为早三叠世早期的含泥质、粉砂质的碳酸盐岩沉积,含丰富的菊石。本区除雁石剖面二叠、三叠系作过比较系统的研究外(杨遵仪等,1987;吴顺宝等,1988),其他地区相当地层的系统研究做得较少。The ammonoid fauna described here from the successive strata of the uppermost Permian and the lowermost Triassic in western Fujian may be divided into four zones, i. e., the Tapashanites, Pseudotirolites-Pleuronodoceras, Rotodiscoceras and Hypophiceras zones in ascending order. Among them, the first three zones belong to the Upper Permian Changhsingian Stage, predominated by the abundant occurrence of the Cathaysian ammonoids, and the last one is referred to Lower Triassic characterized by the presence of the Hypophiceras fauna. The Permian-Triassic boundary is marked by the first appearance of Hypophiceras.DESCRIPTION OF NEW SPECIES Genus Pernodoceras Chao et Liang, 1971 Pernodoceras yonganense sp. nov. (P1. Ⅱ, fig. 9; P1. Ⅲ, fig. 2)Diagnosis Shell moderately large, with a diameter of 59 mm in large specimen, evolute, discoidal, with arched renter marked by medial keel Lateral sides rather flattened, ornamented with fine ribs in early stage, turning strong, with terminal nodes on the ventrolateral portion, and tending to become narrow and high, with about 20 nodes on the last volution. Umbilicus wide and shallow. U/D approximately 50% at maturity. Suture line unknown.Comparison The new species differs from all other representatives of the genus in its thin shell and dense nodes.Horizon and Locality Upper Permian Yanshi Formation, Yong'an, Fujian.Pernodoceras fenghaiense sp. nov. (P1. Ⅲ, fig, 1)Diagnosis Shell rather large, greater than 80 mm in diameter, evolute, discoidal. Venter rather arched, with a weak keel. Lateral sides rather flattened, inclining toward the umbilicus. Transverse ribs on side weak to strong; ventrolateral nodes small to large, with about 8—9 terminal nodes on the last volution. Umbilicus wide and shallow. U/D less than 50% at maturity. Suture line unknown.Comparison This new species differs from P. yonganense sp. nov. in having less but large terminal nodes.Horizon and Locality Ibid.

关 键 词：菊石 二叠世 三叠世 动物群 福建 

分 类 号：Q915.818.4[天文地球—古生物学与地层学]