东昆仑山北坡早三叠世Spathian期菊石群的发现  

DISCOVERY OF SPATHIAN AMMONOID FAUNA FROM EASTERN KUNLUN MOUNTAINS

作　　者：王义刚[1] 杨志荣 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008 [2]新疆地质矿产局第一区域地质调查大队,新疆奇台831800

出　　处：《古生物学报》1992年第3期350-356,399,共7页Acta Palaeontologica Sinica

摘　　要：东昆仑山北坡早三叠世Spathian期的菊石群由Procarnites kokeni(Arthaber),P. kunlunensis sp. nov. 和Proptychitoides trigonalis(Arthaber)组成。它们的出现表明早三叠世的海水已到达东昆仑山,所谓的三叠纪古昆仑山,至少其东部尚不存在,其古海岸线至少应划在阿尔金山与昆仑山之间。Procarnites-Proptychitoides菊石群的出现被看作是陆架深水或斜坡相的标志。由此推测,当前Procarnites-Proptychitoides群落的产地以北,应有陆架浅水相的沉积。同时,以阿尔金山为北缘、昆仑山为南缘的柴达木盆地的下面很可能隐伏有海相三叠系。从邻区布尔汗布达山(作为东昆仑山的东延部分)发育良好的旱、中三叠世海相沉积,笔者推测东昆仑山的海侵起自早三叠世,并延续至中三叠世。A Spathian ammonoid fauna of the late Early Triassic has been found for the first time from the northern slope of the Eastern Kunlun Mountains about 100km south of Qiemo (Qarqan) county, Xinjiang. The fauna contains 2 genera with 3 species, namely, Procarnites kokeni (Arthaher), P. kunlunensis sp. nov. and Proptychitoides trigonalis (Arthaber). Their appearance indicates that the sea water of Early Triassic could go across the Kunlun Mountains. At that time, the socalled Palaeo-Kunlun Mountains, at least its eastern part, was untenable, and the coastal line at least should be drawn between the Kunlun and Altun Mountains. Recently, the appearance of the ammonoid Procarn#es-Proptychitoides community was recognized as a mark of deeper shelf or slope facies (Wang, 1988). However, in normal case, there should be a shallow shelf facies lying north of the present locality with the occurrence of the Procarnites-Proptychitoides community. Therefore, it is reasonable for us to conjecture that the transgressive water might have extended into the Altun Mountains at that time. It is also wor.thwhile for us to think deeply about whether or not the Qaidam Basin with the Altun Mountains as northern fringe and the Kunlun Mountains as southern fringe has ever developed marine ,Triassic deposits underground. Based on the well developed marine Lower and Middle Triassic in Mt. Burhan Bud which is the eastern extension of the Kunlun Mountains, it can be inferred that the marine transgression might have ranged from Early Triassic to Middle Triassic in the area of the Eastern Kunlun Mountains, and even the Altun Mountains. DESCRIPTION OF NEW SPECIES Procarnites kunlunensis sp. nov. (P1. Ⅰ, figs. 7—9; Text-fig. 3) Description Only one specimen observed. Shell medium-sized, 44.1mm in diameter, with whorl 17.5mm in width, 22.0mm in height and umbilicus 7.9mm in width. Widest point situated at the inner part of flank. Venter gently arched; ventrolateral shoulder subangular. Sur

关 键 词：东昆仑山 Spathian期 菊石群 

分 类 号：Q915.818.4[天文地球—古生物学与地层学]