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DOI	10.1016/j.palaeo.2019.109290
	Thermal maturity of carbonaceous material in conodonts and the Color Alteration Index: Independently identifying maximum temperature with Raman spectroscopy
	McMillan R.; Golding M.
发表日期	2019
ISSN	0031-0182
卷号	534
英文摘要	The Color Alteration Index (CAI) of conodont specimens is commonly used for identifying the maximum temperature to which units of sedimentary rock, particularly carbonates, have been heated. Observable color variations in these fossils are thought to be a result of the thermally-induced structural evolution of organic carbonaceous matter (CM). Such temperature history information is extremely valuable for applications in hydrocarbon exploration as well as for constraining other temperature-related geological processes in sedimentary systems. However, the identification of CAI depends on the qualitative visual assessment of color, which, along with a host of other potential complications, may yield inaccurate determinations of maximum temperature. Raman spectroscopy allows thermally-induced structural changes in CM to be quantified, and it has been used to estimate the thermal maturity in metasedimentary rocks for almost two decades. Here, we use Raman spectroscopy of carbonaceous material (RSCM) in conodont specimens and their Mississippian to Upper Triassic host rocks from British Columbia, Canada, to estimate maximum temperatures based on the transformation (structural reorganization) of disordered carbon to graphite. This study demonstrates that the maximum temperatures experienced by conodont specimens, as calculated from RSCM using the Iterative Fitting of Raman Spectra (IFORS) technique, correlate well with CAI but lie outside the suggested ranges in some instances. This may be due to complex thermal histories of these conodont specimens or the influence of diagenetic alteration, not thermal histories, on conodont color. We recommend the application of Raman spectroscopic analyses of CM in conodonts and their host rocks to obtain more confident, accurate, and precise estimations of maximum temperature that are independent of CAI. © 2019 Elsevier B.V.
英文关键词	Cache Creek Terrane; CAI; Haida Gwaii; Mississippian; Upper Triassic; Wrangell Terrane
语种	英语
scopus关键词	carbonaceous chondrite; conodont; diagenesis; fossil record; host rock; hydrocarbon exploration; identification method; index method; Mississippian; Raman spectroscopy; sedimentary rock; terrane; thermal maturity; Triassic; British Columbia; Cache Creek; California; Canada; Queen Charlotte Islands; United States
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150809
作者单位	Pacific Centre for Isotopic and Geochemical Research, Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia, 2020-2207 Main Mall, Vancouver, BC V6T 1Z4, Canada; Geological Survey of Canada, Pacific Division, 1500-605 Robson Street, Vancouver, BC V6B 5J3, Canada
推荐引用方式 GB/T 7714	McMillan R.,Golding M.. Thermal maturity of carbonaceous material in conodonts and the Color Alteration Index: Independently identifying maximum temperature with Raman spectroscopy[J],2019,534.
APA	McMillan R.,&Golding M..(2019).Thermal maturity of carbonaceous material in conodonts and the Color Alteration Index: Independently identifying maximum temperature with Raman spectroscopy.Palaeogeography, Palaeoclimatology, Palaeoecology,534.
MLA	McMillan R.,et al."Thermal maturity of carbonaceous material in conodonts and the Color Alteration Index: Independently identifying maximum temperature with Raman spectroscopy".Palaeogeography, Palaeoclimatology, Palaeoecology 534(2019).