新疆克拉麦里地区中及上志留统划分与对比

根据岩性和生物组合特征,该区的志留纪地层划分为:中志留统白山包组,上志留统下部红柳沟组,上部苦水泉组.白山包组为粉砂岩和细砂岩,夹钙质砂岩和少量砾岩,钙质砂岩中含腕足类化石:Tuvaella rackovskii,T.gigangea, Stegerhynchus angaciensis,Tannusp-irifer,Spiriferina,Zygospiraella,Resserella obicularia,Leptostrophia elegestica等,以及三叶虫:Encrinurus.红柳沟组为钙质细砂岩、泥质灰岩、生物碎屑灰岩,灰岩中化石十分丰富,含床板珊瑚:Favosites cf.zhifangensis,Mesofavosites shang-siensis,Hil aepora,Pseudoplasmopora;四射珊瑚:Amsdenoides,Laccophyllumetc.:三叶虫:Encrinurus,Phacops:头足类:Geisonoceras,Michelinoceras等.与白山包组整合接触.苦水泉组整合在红柳沟组之上,为中厚层状凝灰质粉砂岩、细砂岩、沉凝灰岩,夹少量钙质砂岩和砾岩,在下部发现床板珊瑚(Favosites)、四射珊瑚(Petraia,Hapsiphyllum,Syringa-xon)、三叶虫(Encrinurus)、腹足类及放射虫化石.该区中及上志留统可与中国新疆北部、东北、内蒙、蒙古及苏联等地同期地层进行对比.

DIVISION AND CORRELATION OF MIDDLE AND UPPER SILURIAN IN THE KELAMAILI REGION OF XINJIANG

The Kelamaili Region is located in the southern part of the Kelamaili deep fracture of the eastern Junggar region in Xinjiang, analogous to the western part of the Tuvaella biographical province. Based on lithologics and biotic association character, the Silurian strata in the region can be divided into Middle and Upper Series as follows: the Middle Silurian -Baishanbao Formation, the lower part of the Upper Silurian-Hongliugou Fm., the upper part of the Upper Silurian-kushuiquan Fm. Baishanbao Fm.consists of grey, greyish-green siltstone and fine sandstone with calcareous sandstone and a little coglomerate, thickness 181-237m.The faunas from the calcareous sandstone include brachiopods such as Tuvaella rackovskii, T. gigan-tea, Stegerhynchus angaciensis, Tannuspirifer, Spirigerina, Zygospiraella, Resserella obicularia, Leptostrophia elegestica etc. and trilobite (Encrinurus) . The strata can be compared with the same strata in Northeast China, Inner Mongolia and Altai, Tuva, the Far East of USSR, as well as Mongolia. Hongliugou Fm. are composed of dark grey, brownish-grey, purplish-red calcareous fine sandstone, pelitic limestone, bioclastic limestone, having a thickness of 63-333m. The fossil faunas from the limestone are rich and varied, in eluding Tabulate ( Favosites cf. zhifangensis, Mesofavosites shangsiensis, Hillaepora, Pseudoplasmopora) , Rugosa corals (Amsden-oides, Laccophyllum etc.) , Trilobite ( Encrinurs, Phacops) and Cephalopods (Geison-oceras, Michelinoceras) . The strata He conformably in contact with the Baishanbao Fm.. Kushuiquan Fm. is inconformity with the Hongliugou Fm.. The rocks are dark grey, greyish-green, purplish-red midium-thick bedded tuffaceous, fine sandstone, tuffite with a little calcareous sandstone and conglomerate, having a thickness of 381-671m.A few Tabulate (Favosites) , Rugosa corals (Petraia, Hapsiphy-llum, Syringaxon) Trilobite (Encrinurus) Gastropoda and Radiolaria are discovered in the lower part of the Formation. The Upper Silurian in the region can be compared with the same strata in the northern part of Xinjiang, Northeast China, Inner Mongolia, and USSR, Mongolia as well.