IGGCAS OpenIR  > 兰州油气中心
Formation phases of carbonate cements and sedimentary environments in lower Jurassic sandstones of the Lenghu V tectonic belt, North Qaidam Basin, China
Guo, Jiajia1,2; Sun, Guoqiang1; Liu, Weiming1,2
2019-12-01
Source PublicationCARBONATES AND EVAPORITES
ISSN0891-2556
Volume34Issue:4Pages:1367-1379
AbstractBased on petrography and geochemistry, formation phases of carbonate cements and their sedimentary-diagenetic environments in Jurassic clastic rocks from the Lenghu V tectonic belt are determined. The results demonstrate that studied successions are mainly dark gray or black mudstone with interbedded thin gray siltstone and a few greywacke layers. Sandstones are lithic and feldspathic lithic greywacke with high kaolinite content. Calcite and ferrocalcite are the main carbonate cements. The carbon isotope values(delta C-13) of the carbonate cements range from - 15.6 to 9.2 parts per thousand (average - 3.2 parts per thousand) with a bimodal distribution. One peak is 4 parts per thousand, which includes samples from the upper Xiaomeigou Formation (Fm) and the other one is - 12 parts per thousand, which mainly represents the lower section. The oxygen isotope values(delta O-18) have a wide range from - 18.5 to - 8.3 parts per thousand (average - 13.31 parts per thousand). Combined with microscopic observations, two phases of carbonate cements are distinguished according to their isotopic characteristics. The earlier carbonate cements are mainly calcite and ferrocalcite, and they were precipitated in eodiagenesis stage. The carbon source of calcite was inorganic, and ferrocalcite was mixed with carbon from methanogenesis. This mixture led to a positive bias in the delta C-13 curve, which artificially inflated the paleosalinity. The later carbonate cements, formed in mesodiagenesis stage, were ferrocalcite. Decarboxylation of organic matters led to lower delta C-13 values. The major and trace elements data show that Sr, Ba, Fe and Mn have weak correlation with Al, Ti. So, they are effective to interpret the sedimentary environment. The Sr/Ba ratio < 1 indicates fresh water environment, Sr/Ca, Sr/Cu and Fe/Mn ratios suggest humid climate, and V/(V + Ni) ratio shows suboxic-anoxic environment. The carbon and oxygen isotopes, together with elemental geochemistry, show that the climate during the Early Jurassic was warm and wet and the studied successions were deposited in fresh water. The variations in elemental ratio curves indicate that climate became wetter and warmer later in the Early Jurassic.
KeywordCarbon isotope Oxygen isotope Carbonate cements Sedimentary environment Qaidam Basin
DOI10.1007/s13146-018-0439-9
WOS KeywordISOTOPIC COMPOSITION ; GEOCHEMISTRY ; MINNESOTA ; ULM
Language英语
WOS Research AreaGeology
WOS SubjectGeology
WOS IDWOS:000496621400013
PublisherSPRINGER
Citation statistics
Document Type期刊论文
Identifierhttp://ir.iggcas.ac.cn/handle/132A11/95835
Collection兰州油气中心
Corresponding AuthorSun, Guoqiang
Affiliation1.Chinese Acad Sci, Inst Geol & Geophys, Gansu Prov Key Lab Petr Resources Res, Key Lab Petr Resources, Lanzhou 730000, Gansu, Peoples R China
2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
First Author AffilicationInstitute of Geology and Geophysics, Chinese Academy of Sciences
Corresponding Author AffilicationInstitute of Geology and Geophysics, Chinese Academy of Sciences
Recommended Citation
GB/T 7714
Guo, Jiajia,Sun, Guoqiang,Liu, Weiming. Formation phases of carbonate cements and sedimentary environments in lower Jurassic sandstones of the Lenghu V tectonic belt, North Qaidam Basin, China[J]. CARBONATES AND EVAPORITES,2019,34(4):1367-1379.
APA Guo, Jiajia,Sun, Guoqiang,&Liu, Weiming.(2019).Formation phases of carbonate cements and sedimentary environments in lower Jurassic sandstones of the Lenghu V tectonic belt, North Qaidam Basin, China.CARBONATES AND EVAPORITES,34(4),1367-1379.
MLA Guo, Jiajia,et al."Formation phases of carbonate cements and sedimentary environments in lower Jurassic sandstones of the Lenghu V tectonic belt, North Qaidam Basin, China".CARBONATES AND EVAPORITES 34.4(2019):1367-1379.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Guo, Jiajia]'s Articles
[Sun, Guoqiang]'s Articles
[Liu, Weiming]'s Articles
Baidu academic
Similar articles in Baidu academic
[Guo, Jiajia]'s Articles
[Sun, Guoqiang]'s Articles
[Liu, Weiming]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Guo, Jiajia]'s Articles
[Sun, Guoqiang]'s Articles
[Liu, Weiming]'s Articles
Terms of Use
No data!
Social Bookmark/Share
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit Add to Technorati
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.