Citation: | LI Xin, CAO Hong, GENG Wei, SUN Zhilei, ZHANG Xilin, YAN Dawei, QIN Shuangshuang, XU Cuiling, ZHANG Xianrong, ZHAI Bin, WANG Libo. Research progress in carbonate associated sulfate[J]. Marine Geology & Quaternary Geology, 2020, 40(3): 119-131. doi: 10.16562/j.cnki.0256-1492.2019090801 |
Carbonate associated sulfate, or CAS in brief, is one of the important indicators for paleoenvironmental restoration. Trace sulfate may enter carbonate lattice and replaces the carbonate during diagenesis. The CAS has the capability to preserve the isotopic composition of seawater sulfate and to record the sulfate concentration of seawater, as well as the changes in the paleoenvironment. In recent years, CAS has attracted great interest and attention from the geological society. In this paper, attempt has been made to address CAS with emphases on its pre-treatment methods, influencing factors, isotopic composition and its significance in paleoenvironmental reconstruction. The application of CAS to the restoration of different sedimentary environments is discussed, in addition to the future research directions. We hope that the introduction may raise interests and attentions from researchers.
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Correlation of δ34SCAS versus δ18OCAS(data from reference[ 25])
Recommended protocol for the extraction of CAS (CAS is carbonate associated sulfate, CRS is chromium-reducible sulfur[2, 31])
CAS isotopic composition versus inverse concentration with all Anticosti Island specimens[57]
δ18OCAS versus δ34SCAS values of Gulf of Mexico seep carbonates grouped by dominant mineral composition (Black cross corresponds to δ18O and δ34S composition of modern seawater (SW)sulfate[48])
δ18OCAS versus δ34SCAS values of seep carbonates from modern seafloor (Red for modern aragonite and green for ancient calcite[48])
The Studies of the high-resolution sulfur isotope stratigraphy of seawater sulfate[64, 74-75]
Walker Lake sulfate concentration between 1900 and 1995 AD[82]
CAS versus Walker Lake sulfate concentration[82]