CAJ | 학술논문

安徽巢湖平顶山地区上二叠统大隆组主要为硅质泥岩和泥岩互层沉积.通过对该剖面微体古生物化石丰度的统计分析发现,其演化可划分出4个阶段:I(繁盛阶段)→II(衰亡阶段)→III(恢复阶段)→IV(大衰亡阶段).利用微量元素Cu、Ni和Zn估算了巢湖平顶山剖面古生产力,其平均值为1.48 gC/m~2 d,与北美二叠系黑色页岩的古生产力平均值(1.40 gC/m~2 d)和现代海洋大陆架的初级生产力(如委内瑞拉大陆架为1.50 gC/m~2 d)较为一致.大隆组中有机碳质量分数为0.26%～5.49%,有机质富集程度和古生产力大小与岩性关系密切:泥岩和粉砂质泥岩里有机质最为富集且古生产力较高;而在硅质泥岩中,两者含量相对较低.分析了有机质富集过程(从生物物质到沉积有机质,再到埋藏有机质)中各环节的主要影响因素,表明海洋古生产力是有机质富集的主导因素和前提条件,直接影响沉积物中的有机质含量,而海洋表层初级生产力的大小受上升流、营养盐和海水深度等环境因素综合影响;在埋藏有机质阶段,其主控因素为沉积环境中的氧含量和沉积速率等.综合研究表明,本剖面中有机质富集为生产力模式,即:岩石中有机质的富集受古生产力的影响最大,其次为沉积环境中的氧含量.其中,古生产力由生产者贡献,但是受消费者的丰度影响较大.
안휘소호평정산지구상이첩통대륭조주요위규질니암화니암호층침적.통과대해부면미체고생물화석봉도적통계분석발현,기연화가화분출4개계단:I(번성계단)→II(쇠망계단)→III(회복계단)→IV(대쇠망계단).이용미량원소Cu、Ni화Zn고산료소호평정산부면고생산력,기평균치위1.48 gC/m~2 d,여북미이첩계흑색혈암적고생산력평균치(1.40 gC/m~2 d)화현대해양대륙가적초급생산력(여위내서랍대륙가위1.50 gC/m~2 d)교위일치.대륭조중유궤탄질량분수위0.26%～5.49%,유궤질부집정도화고생산력대소여암성관계밀절:니암화분사질니암리유궤질최위부집차고생산력교고;이재규질니암중,량자함량상대교저.분석료유궤질부집과정(종생물물질도침적유궤질,재도매장유궤질)중각배절적주요영향인소,표명해양고생산력시유궤질부집적주도인소화전제조건,직접영향침적물중적유궤질함량,이해양표층초급생산력적대소수상승류、영양염화해수심도등배경인소종합영향;재매장유궤질계단,기주공인소위침적배경중적양함량화침적속솔등.종합연구표명,본부면중유궤질부집위생산력모식,즉:암석중유궤질적부집수고생산력적영향최대,기차위침적배경중적양함량.기중,고생산력유생산자공헌,단시수소비자적봉도영향교대.
The Upper Permian Dalong Formation in Pingdingshan section, Chaohu area, is an interbedding deposition composed mainly of siliceous mudstone and mudstone. Through the statistical analysis of the micro-fossils abundance in Pingdingshan section, we found that its evolution can be divided into four stages: the flourish stage, the decline stage, the recovery stage and the large decline stage. The average paleoproductivity calculated by Cu, Ni, and Zn in this section is 1. 48 gC/m~2d, which is consistent with the previously reported data (1. 40 gC/m~2d) for the black shale of the Phosphoria Formation, a Permian phosphate deposit in northwestern United States, and also similar to that of the modern deposit in the Cariaco Basin, Venezuela (1.50 gC/m~2d). The content of total organic carbon (TOC) in the Upper Permian Dalong Formation ranges from 0. 26% to 5. 49%. TOC and the paleoproductivity is closely related with the host lithology. The results show that high TOC and high paleoproductivity occur in the mudstone and the silty mudstone, while relatively low in the siliceous shale. This paper analyzes the main factor affecting the organic matter enrichment process, which is from organisms to deposited organic matter to burial organic matter. It indicates that the paleoproductivity which controls the organic matter in sediments is the predominant factor and the prerequisite for the enrichment of organic matter in rocks. The primary productivity of the marine surface is influenced by several environmental factors, such as upwelling, nutrient salts, depth and so on. And the main factors which affect the organic matter enrichment are the sedimentation rate and the oxygen content at the stage of deposited organic matter. The comprehensive research indicates that the main factors which affect organic matter enrichment in this section are the paleoproductivity, and then the oxygen content of sedimentary environment. The paleoproductivity is determined by the abundance of primary producers, while, affected mainly by the abundance of customers.