After tracking the historical distribution of the pectinids being very capable of dispersion, it is easy to be found that the bivalves Chlamys (Chlamys) valoniensis (Defrance), Camptonectes (Camptonectes) auritus (von Schlo-theim) and Chlamys (Chlamys) textoria (von Schlotheim) first occurred in the Late Rhaetian, the end of the Triassic, or the earliest Hettangian, the earliest Jurassic of western Europe, and subsequently they spread into the southeastern coast of Palaeo-pacific through the Hispanic Corridor during the Hettangian or a little later. It has demonstrated that the Hispanic epicontinental seaway became established along the rifting area between North America and South America and Africa of the Pangaean supercontinent as early as Hettangian or even earlier, connecting western Tethys and eastern Palaeo-pacific and providing a corridor for migration and exchange of creatures between Tethys and Palaeo-pacific.
SHAJingengNanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China (e-mail: jgsha @nigpas.ac.cn)
最近在黑龙江省东部鸡西盆地穆棱河右岸青龙山一带穆棱组标准剖面地层中发现多属种海相沟鞭藻化石:Circulodinium cingulatum He et al,Circulodinium attadalucum(Cookson et Eisenack)Helby,Palaeoperidinium cretaceum Pocock,Oligosphaeridium totum Brideaux及Sentusidinium sp.,它们都是世界各地早白垩世海相地层中广泛分布的属种。这些化石的发现表明,在穆棱组沉积时期,鸡西盆地曾经历过海侵或海泛,修正了以往所谓的穆棱组为纯陆相沉积的观点,并为穆棱组地质时代的确认提供了新的依据,也为黑龙江省东部早白垩世古地理的重建提供了重要的海相沉积依据。
The low diversity agglutinated foraminifers are recovered from the Qihulin Formation of the Longzhaogou Group in eastern Heilongjiang, China. The foraminiferal fauna consists of 9 species of 5 genera. The common members are Cribrostomoides nonioninoides (Reuss), Haplophragmoides concavus (Chapman), H. gigas minor Nauss. Although the diagnostic zonal taxa are absent in the agglutinated fauna, according to the global stratigraphic distribution of the above-mentioned species, and the associated Pseudohaploceras ammonite fauna, the foraminiferal fauna may be of a Barremian-Aptian (Early Cretaceous) age.
LI Gang & YU Shanmao1. State Key Laboratory of Paleobiology Stratigraphy, Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China
Newly discovered marine dinoflagellates from the lower-middle parts of the Lower Cretaceous Muling Formation of the Jixi Basin, eastern Heilongjiang Province, China, were identified as Circulodinium cingulatum He et al., C. attadalicum (Cookson et Eisenack) Helby, Palaeoperidinium cretaceum Pocock, Oligosphaeridium totum Brideaux and Sentusidinium sp. Most of these species are distributed in the marine Lower Cretaceous strata of Europe, North America, Africa, Australia and Asia. It demonstrates that a transgression occurred in eastern Heilongjiang Province during the deposition of the Muling Formation, which was previously considered to be a coal-bearing continental stratigraphic unit. The marine dinoflagellates indicated that the Muling Formation is Barremian in age. The Palaeogeographic framework of eastern Heilongjiang Province in Late Mesozoic era should be rebuilt through systematic facies analyses of the marine, paralic and terrestrial deposits.
