Comparative study of Cambrian lobopods <Emphasis Type="Italic">Miraluolishania</Emphasis> and <Emphasis Type="Italic">Luolishania</Emphasis>

The rare fossil Miraluolishania described by Liu et ah from the Lower Cambrian Chengjiang Lagerstatte in 2004 is regarded as an arthropod sphinx because it bears mosaic features of both Iobopods and arthropods. The discovery of this rare transitional form offers direct fossil evidence for exploring the relationship between Iobopods and arthropods. However, some scientists consider Miraluolishania to be a junior synonym of Luolishania because the former superficially resembles the latter in general appearance. Considering the significant differences between the two taxa, a thorough comparative study of Miraluolishania and Luolishania leads to the conclusion that there are definitely two different genera. Nevertheless, the ＂Luolishania＂ of the Haikou area is indeed ＂Miraluolishania＂, whereas Luolishania is most likely the typical genus of the Maotianshan area of Chengjiang County.     

A new section of Kaili Formation （Cambrian） and a biostratigraphic study of the boundary interval across the undefined Cambrian Series 2 and Series 3 at Jianshan,Jianhe County,China with a discussion of global correlation based on the first appearance datum of Oryctocephalus indicus （Reed, 1910）

A trilobite biostratigraphic study of a new section of the Kaili Formation at Jianshan, Chuandong Village, Jianhe County, Guizhou is reported. Additional occurrences of key species associated with the Ovatoryctocara granulata-Bathynotus holopygus Zone and the overlying Oryctocephalus indicus Zone that were originally defined from the trilobite assemblages at the WuliuZengjiayan section of the Kaili are reported from this new section. The first appearance datum （FAD） of Oryctocephalus indicus occurs at the 44.52 m above the base of the unit. Based on study of abundant specimens （n = 800） from the Kaili Formation, we argue that Oryctocephalus indicus is a widespread taxon with a global distribution. O. reticulatus （Lermontova, 1940） from the middle part of the Kounamkites Zone of the Amganian Stage in the Molodo River region of Siberia and O. americanus （Sundberg and McCollum, 2003） from Nevada, North America are similar to representatives of O. indicus which occur in the O. indicus Zone of the Kaili Formation. O. reticulatus and O. americanus are here synonymized with O. indicus （Reed, 1910）. This study strengthens the Wuliu-Zengjiayan section of the Kaili Formation as a candidate section for a Global Stratotype for the base of the unnamed Cambrian Series 3.     

四川盆地周缘筇竹寺组泥页岩储层特征

通过地表地质和井下地质相结合,运用岩石学和岩石物理学方法,探讨了四川盆地周缘下寒武统筇竹寺组泥页岩储层特征.结果表明,四川盆地周缘下寒武统筇竹寺组厚40～400m,为一套黑色碳质泥页岩、灰色含粉砂泥岩、粉砂岩、细砂岩、灰岩及含泥灰岩建造.筇竹寺组下部岩性主要由富有机质(碳质)非纹层状泥页岩、泥岩、钙质泥岩、粉砂岩、纹层...