防灾减灾学报
防災減災學報
방재감재학보
Seismological Research of Northeast China
2015年
3期
95-100
,共6页
化石碳酸盐岩%微相%下寒武统%沉积环境
化石碳痠鹽巖%微相%下寒武統%沉積環境
화석탄산염암%미상%하한무통%침적배경
fossil carbonate%microfacies%Cambrian%sedimentary environment
江苏省徐州市大北望剖面早寒武世馒头组的碳酸盐岩地层发育较好,沉积类型多样,成岩特征明显,是研究碳酸盐岩沉积及成岩作用的理想剖面之一。文章采用微相分析的方法,对该剖面碳酸盐岩的生物组合、颗粒成分、基质类型及其结构等微相特征做了研究。根据颗粒类型、沉积结构和化石,本区的碳酸盐岩可以被分为3个大类和10种化石碳酸盐岩微相类型:泥晶颗粒灰岩(微相1至微相5),颗粒泥晶灰岩(微相6至微相8)和泥晶灰岩(微相9和微相10)。每一种微相对应特定的沉积环境及演化特征。综合分析表明,研究区下寒武统形成于泻湖、局限台地、开阔台地和台地边缘的浅滩环境,据此建立了沉积相模式。在徐州大北望地区进行的关于碳酸盐岩微相的研究表明早寒武世晚期的馒头组继承了早寒武世中期的特点,且海侵持续扩大的持续沉降活动。
江囌省徐州市大北望剖麵早寒武世饅頭組的碳痠鹽巖地層髮育較好,沉積類型多樣,成巖特徵明顯,是研究碳痠鹽巖沉積及成巖作用的理想剖麵之一。文章採用微相分析的方法,對該剖麵碳痠鹽巖的生物組閤、顆粒成分、基質類型及其結構等微相特徵做瞭研究。根據顆粒類型、沉積結構和化石,本區的碳痠鹽巖可以被分為3箇大類和10種化石碳痠鹽巖微相類型:泥晶顆粒灰巖(微相1至微相5),顆粒泥晶灰巖(微相6至微相8)和泥晶灰巖(微相9和微相10)。每一種微相對應特定的沉積環境及縯化特徵。綜閤分析錶明,研究區下寒武統形成于瀉湖、跼限檯地、開闊檯地和檯地邊緣的淺灘環境,據此建立瞭沉積相模式。在徐州大北望地區進行的關于碳痠鹽巖微相的研究錶明早寒武世晚期的饅頭組繼承瞭早寒武世中期的特點,且海侵持續擴大的持續沉降活動。
강소성서주시대북망부면조한무세만두조적탄산염암지층발육교호,침적류형다양,성암특정명현,시연구탄산염암침적급성암작용적이상부면지일。문장채용미상분석적방법,대해부면탄산염암적생물조합、과립성분、기질류형급기결구등미상특정주료연구。근거과립류형、침적결구화화석,본구적탄산염암가이피분위3개대류화10충화석탄산염암미상류형:니정과립회암(미상1지미상5),과립니정회암(미상6지미상8)화니정회암(미상9화미상10)。매일충미상대응특정적침적배경급연화특정。종합분석표명,연구구하한무통형성우사호、국한태지、개활태지화태지변연적천탄배경,거차건립료침적상모식。재서주대북망지구진행적관우탄산염암미상적연구표명조한무세만기적만두조계승료조한무세중기적특점,차해침지속확대적지속침강활동。
The Mantou Formation of Dabeiwang section, in Xuzhou ,Jiangsu Province, is an ideal section for the study of the Early Cambrian carbonate rock because of the near perfect occurrence and fascinating sedimentary formation. In this paper, microfacies analysis is used, the microfacies characters of the carbonate rock, such as the biotic assemblage, grain composition, the type and texture of the matrix, have been deeply studied. According to types of grains, sedimentary structures and fossils, the carbonate rocks can be recognized as three types consisting of ten kinds of microfacies: grainstone (MF1 to MF5 microfacies) , wackstone (MF6 to GM8 microfacies) and mudstone (MF9 and MF10microfacies). Each microfacies corresponds a designated sedimentary environment and its evolution. It is inferred from the microfacies division and microenvironmental analysis that the Early Cambrian strata were deposited in the lagoon , restricted platform ,open platform and the organic sand at platform edge environments. A facies model has been constructed for the above-mentioned depositional environments. the late Early Cambrian, Mantou Formation inherited the characteristics of the Early Cambrian, transgression continued to expand.