Acta Sedimentologica Sinica

By measuring and describing the section in detail,it comes to a discovery that the Lower Ordovician Panjiazui Formation in Yuanguping area is composed of deep-water carbonate rocks. The rocks are mainly gray micrite,calcarenite and bioclastic limestone. Three types of sediments are developed,namely,vertical landing sediments,gravity flow sediments and contourites. According to lithological characters,the contourites are divided into three types. They are respectively calcilutitic contourite,calcarenitic contourite,and bioclastic contourite. Among them,calcilutitic contourite is well developed,followed by calcarenitic contourite and bioclastic contourite. The development characteristics and the vertical sequences are summarized. Our study shows that there are three types of incomplete contourite sequences in the study area,namely,a single calcilutitic contourite sequence,a calcilutitic-calcarenitic contourite sequence,and a bioclastic-calcarenitic contourite sequence. In the section,the Panjiazui Formation is divided into three parts according to the type and extent of development. From PartⅠ to Part Ⅲ,the proportion of contourite thickness tends to increase. Considering the regional sedimentary background,the contour current strength of this area varied from weak to strong during the sedimentary period of Early Ordovician Panjiazui Formation on the whole,which should form in the mature period of the contourites,so it is significant to study the formation mechanism of this contourites and to define its distribution range.

Luo Shun

Chenji xuebao

Study on Characteristics of Lower Ordovician Contour Current Deposits in Yuanguping,Northern Hunan,China

中国湖南北部元古坪下奥陶统等深流沉积特征研究

Mixed sedimentary rock is referred to the rock composed of terrigenous clastics and carbonate components under mixed sedimentation.In a broad sense,it also includes the spatially alternating layers or intercalations of terrigenious clastic and carbonate components.On the basis of the research on a lot of materials and study on the lower Cretaceous mixed sedimentary reservoir in Qingxi depression of Jiuquan Basin,using methods such as thin-section observation,field-emission scanning electron microscope observation,bulk minerals and clay minerals analysis,mercury injection test and nano-CT,analysis on lithologic associations and reservoir characteristics has been carried out on the mixed sedimentary reservoir.Macroscopically,the mixed sedimentary rock is lithologically complex,composed of dolomitic mudstone,argillaceous dolomite,lime mudstone,lime dolomite and dolomitic limestone,and so on,and presenting three types of vertical profile associations as great suites of thick layers,thick layers intercalated with thin layers and interbedded layers of similar thickness.Microscopically,clay minerals,carbonate minerals and organic matters present laminated or massive distribution form.The mixed sedimentary reservoir develops micro-nanometer scale interparticle pores,intraparticle pores and microfractures.The composition and content of minerals are one of the main factors affecting reservoir space types.Most mixed sedimentary reservoir has low permeability and low porosity,being regarded as tight reservoir.

Li Ting

Characteristics of Mixed Sedimentary Reservoir:Taking the Lower Cretaceous mixed sedimentary rock of Qingxi depression in Jiuquan Basin as an example

混积型储层特征：以酒泉盆地青西凹陷下白垩统混积岩为例

The global glaciation happened in Hirnantian of the Late Ordovician,the lithofacies,biologic facies and sedimentary environment of Hirnantian Kuanyinchiao Formation in the eastern Chongqing and northern Guizhou region,were the response to the glacial event.There were 3 types of lithofacies as a whole.The first type was composed of grainstone with coral.could be subdivided into bioclast limestone,calcarenite,oolitic sparite limestone and spararenite.Which formed in the shoal with medium to high energy.The major components of the second one were the silty limestone and silty argillaceous limestone that formed in tidal flat,where the plentiful brachiopoda and a few trilobites lived.These two types of lithofacies were both the inshore carbonate sediments resulted from sea level drop.The associations of marlstone and calcareous shale,argillaceous siltstone and silty mudstone,and the carbonous marlstone,constituted the last type.And its mixed biofacies containing brachiopoda,trilobites,graptolite,especially the bloomed Hirnantia fauna,indicated the cold water environment and temperature drop of seawater in Principal Glacial Age(Hirnantian).The tidal flat distributed near the Qianzhong(Central Guizhou) Uplift,and the shoal also occupied local area upon the tidal flat,and shallow shelf distributed far away from uplift.As a whole,the sedimentary environment of Kuanyinqiao Formation was shallower than the black shales of Wufeng Formation and Longmaxi Formation formed in anoxic deep-water shelf,the sea-level and seawater temperature was much lower in Hirnantian.All of which were the results influenced by the glacier events in Hirnantian.

Wang Yuan

The Sedimentary Response to Gondwana Glaciation in Hirnantian(Ordovician) of the Eastern Chongqing and the Northern Guizhou Region,South China

中国华南重庆东部和贵州北部地区早奥陶世赫南特期冈瓦纳冰期沉积响应

Saturated hydrocarbons in source rock from member 8 of Yanchang Formation( Upper Triassic) in Ordos Basin were analyzed by GC-MS. Different isomers of monomethylalkanes( MMAs)( carbon number ranging from 12 to31) have been measured on a rock sample from Well Wu 56 located in Wuqi area. MMAs,with different substituted methyl ranging from the second carbon to the middle carbon,have shorter retention time than the corresponding n-alkanes with identical carbon number. 2-methylalkanes and 3-methylalkanes are the most abundant compounds among MMAs,while 4-methylalkanes and other MMAs are relatively low. The positions of the substituted methyl in the MMAs can be identified through typical fragment ions,recombination pattern for chemical bonds,and retention time by mass spectrometry. For example,it has been found that the substituted methyl positions of C22-MMAs are C2-C11.The mass spectrometry is similar to the n-alkane with the same carbon number,m / z57 or m / z 71 is their base peak.They also show a predominant M+peak and( M-15)+peak,suggesting a branched methyl. Moreover,the relative abundance decreases as the total carbon increases. When the methyl position is exceeding the fifth carbon,in comparison with n-alkanes,their major characteristic fragment ions are such m / z126,140,154,as even CnH2 n,which are important to identify MMAs. Generally,a table about the characteristic fragment ions of MMAs are concluded. As well as gas chromatographic unseparated monomethylalkane isomers were resoluted by mass spectrometric deconvolution.Finally,by using of the Kovats index and the homomorphy factors for precise retention prediction and identification of the monomethylalkanes.

Qian Y

Analysis and Identification of Monomethylalkanes in Source Rocks

源岩中单甲基烷烃的分析与鉴定

A prerequisite for the dynamic monitor of modern cave is to provide a reliable basis for the interpretation of a variety or multiple proxies from modern carbonate( Ca CO3) sediment – stalagmites in cave,and to make full use of the multiple proxies from modern carbonate( Ca CO3) sediment in field cave monitoring,and compared to local measuring meteorological data each other and correction,is the key of the accurate and quantitative interpreting multiple climate proxies in stalagmites.The four hydrological years of the meteoric precipitation,cave drips,modern carbonate sediments for 5 sites in No.15 branching cave of Seven Star Cave in Guilin during 2008-2011 were continuously monitored,and the correlation between the δ18O of cave drip and modern carbonate( Ca CO3) and δ18O of the meteoric precipitation were also discussed. The study results have shown that the annual average δ18O value of cave drip and modern carbonate( Ca CO3)is very close to δ18O of the meteoric precipitation and the same change trend,and indicated that the δ18O of cave drip and modern carbonate( Ca CO3) came mainly from δ18O of the meteoric precipitation,that is,it is obviously controlled by δ18O of the meteoric precipitation.In four hydrological years,the year( or annual) change and or many years change trends of δ18O record from the modern secondary chemical carbonate sediments( Ca CO3) and drop water in cave are basically the same and show obvious change characteristics of four peak( low value area of δ18O) and four trough( high value area of δ18O),and has obvious rule of the seasonal change and year change and has the same seasonal characteristics of the meteoric precipitation or heat. The research results shown that δ18O of drip water and modern carbonate( Ca CO3) sediments in cave can record the climate change signal at local or at the top of the cave. So that it has been considered that δ18O of modern carbonate( Ca CO3) sediment in cave is mainly taken as the alternative proxies of the summer monsoon intensity and rainfall amount.

Zhang Mei

Environmental Significance of δ~(18)O Record from Cave Drip Water and Recent Carbonate Deposit at No.15 Branching Cave of Seven Star Cave in Guilin

桂林七星岩15号支洞滴水及近期碳酸盐沉积物δ~(18)O记录的环境意义

The petrological and geochemical data of the Wufeng-Longmaxi Formations in the southern Sichuan Basin were recorded to restore the paleoenvironment and explore the mechanism of organic matter accumulation. The study shows that the Wufeng-Longmaxi Formations in the southern Sichuan Basin mainly developed siliceous shale,silty shale,argillaceous shale,and shell-bearing lime mudstone/muddy limestone. The average total organic carbon（TOC）of the Wufeng Formation is 3.36%,the TOC of the lower Longmaxi Formation is the highest,with an average of 3.99%,and the TOC of the middle and upper parts is low,with an average of 1.22%. Paleoproductivity proxies(Babio,Cu/Al,Ni/Al,and Siexcess)indicate that during most of the Ordovician-Silurian period（except for the Hirnantian period）,the surface water in the southern Sichuan Basin had a high primary productivity. The terrigenous influx proxies（Al,Zr,and Zr/Al）indicate that the terrigenous influx in the Wufeng period was moderate and varied greatly. The early Longmaxi period had a continuous low value,but it gradually increased in the middle and late periods.The correlation between redox-sensitive trace elements（Mo/Al,U/Al,and V/Al）and Mo-TOC shows that,during the Wufeng period,the ocean developed a strong restricted anoxic-euxinic environment. The water mass in the early stage of the Longmaxi maintained anoxic-euxinic conditions,the level of restriction was weakened,and the ocean evolved into an oxic environment in the middle and late periods. In the Late Ordovician,a favorable anoxic-euxinic environment and high productivity developed in the ocean,but the large amount of terrigenous influx weakened the organic matter accumulation. In the Early Silurian,sea level fluctuations caused multiple environmental parameters to coordinately change,which resulted in significant differences in the concentration of organic matter.

Huang ZiSang

Wang XingZhi

Yang XiYan

Zhu RuKai

Cui JingWei

LU YuanZheng

Li Yong

Gas Reservoir Geology

Exploitation

Constraints of Sedimentary Environment on Organic Matter Accumulation in Shale: A case study of the Wufeng-Longmaxi Formations in the southern Sichuan Basin

沉积环境对页岩有机质富集的制约——以四川盆地南部五峰-龙马溪组为例

Zhang MingYu

Chang Xin

HU LiMin

BI NaiShuang

Wang HouJie

Liu XiTing

Source-to-Sink Process of Organic Carbon on the Inner Shelf of the East China Sea and its Sedimentary Records

东海内陆架有机碳的源汇过程及其沉积记录

短名	CHENJI XUEBAO
期刊索引	北大核心中国科学引文数据库中国科技核心期刊目录

ISSN	1000-0550
h-index	16

涉及主题	sedimentologygeology
出版信息	出版商: Science China Press，出版周期: ，期刊类型: journal，开源期刊: 是
基本数据	创刊年份: 2019，原创研究文献占比: ，自引率:， Gold OA占比:
期刊费用	$详情
平均审稿周期	25 weeks

Acta Sedimentologica Sinica

期刊引文格式

有 1 位以上作者的期刊

有 2 位作者的期刊

有 3 位作者的期刊

有 5 位以上作者的期刊

书籍引用格式

学位论文引用格式

网页引用格式

专利引用格式

手工熬夜修改参考文献？研飞自动匹配期刊，一键轻松成稿，支持 Word/WPS

投稿经验分享

Study on Characteristics of Lower Ordovician Contour Current Deposits in Yuanguping,Northern Hunan,China

Characteristics of Mixed Sedimentary Reservoir:Taking the Lower Cretaceous mixed sedimentary rock of Qingxi depression in Jiuquan Basin as an example

The Sedimentary Response to Gondwana Glaciation in Hirnantian(Ordovician) of the Eastern Chongqing and the Northern Guizhou Region,South China

Analysis and Identification of Monomethylalkanes in Source Rocks

Environmental Significance of δ~(18)O Record from Cave Drip Water and Recent Carbonate Deposit at No.15 Branching Cave of Seven Star Cave in Guilin

Constraints of Sedimentary Environment on Organic Matter Accumulation in Shale: A case study of the Wufeng-Longmaxi Formations in the southern Sichuan Basin

Source-to-Sink Process of Organic Carbon on the Inner Shelf of the East China Sea and its Sedimentary Records

Constraints of Sedimentary Environment on Organic Matter Accumulation in Shale: A case study of the Wufeng-Longmaxi Formations in the southern Sichuan Basin

Source-to-Sink Process of Organic Carbon on the Inner Shelf of the East China Sea and its Sedimentary Records

Constraints of Sedimentary Environment on Organic Matter Accumulation in Shale: A case study of the Wufeng-Longmaxi Formations in the southern Sichuan Basin