气候变化领域集成服务门户(CCPortal): Carbonate clumped isotope (Delta(47)) thermometry and its application in paleoelevation reconstruction

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DOI	10.1360/N972019-00032
	Carbonate clumped isotope (Delta(47)) thermometry and its application in paleoelevation reconstruction
	Xiong, Zhongyu; Ding, Lin; Xie, Jing
通讯作者	Ding, L (通讯作者)
发表日期	2019
ISSN	0023-074X
EISSN	2095-9419
起始页码	1722
结束页码	1737
卷号	64 期号:16
英文摘要	Paleoaltimetry provides crucial constraints on tectonic processes and precise paleotemperature measurement is an important component in paleoelevation reconstruction. Carbonate clumped isotope thermometry is based on homogeneous isotope equilibrium and is used to provide direct estimation of carbonate formation temperature independent of delta O-18 of the parent water from which the carbonate formed. The error regarding clumped isotope temperature estimation can be reduced to +/- 2 degrees C. The characteristics of temperature-dependence, and the small uncertainty using carbonate clumped isotope thermometry, greatly improve accuracy and precision in paleoelevation reconstruction. In this review, we introduce the basic theory, laboratory methodology and standardization processes underpinning carbonate clumped isotope thermometry. Theoretical calculations indicate a linear relationship between parameter Delta(47) and 1/T-2, which establishes the foundation from which carbonate clumped isotopes provide reliable paleotemperatures. The laboratory treatment of carbonate includes two systems: the modified Kiel IV device for small weight samples (0.15-0.2 mg) installed within microvolume nitrogen traps and packed microvolume columns; and a heavy sample device that is installed with McCrea/common bath acid digestion devices, nitrogen traps and packed columns. These systems are designed to remove potential interference from water and hydrocarbons in the CO2. The measurement of purified CO2 is finished on gas source isotope mass ratio spectrometry (IMRS), especially on MAT 253 and 253 Plus machines. The standardization of the Delta(47) to an absolute reference frame (ARF) accounts for the non-linearity and scaling effect of the IMRS, and the ARF also enables direct comparison of data from different laboratories. The practical procedure for the standardization includes interpolating the relationship between the measured delta(47) and Delta(47) of the equilibrium gases, and conversion of the measured Delta(47) to theoretical values to derive an empirical transfer function. Due to the great potential for solving Earth science problems, empirical calibration of the carbonate clumped isotope thermometry has been explored over a wide range of temperature in different types of carbonates, but is still plagued by discrepancies between different calibrations, probably due to variability in acid preparation, CO2 purification and data reduction methods. We summarized all the published synthetic calcite data to ARF with the same acid fractionation factor and yield a composite empirical calibration that could resolve the discrepancies between different calibrations. However, bio-genetic carbonates still fail to yield a universal empirical calibration, even when using the same methodology. The cause of this difference is probably due to different environmental, species discrimination and vital effects. The application of carbonate clumped isotope thermometry to paleoaltimetry is based on the theory that the delta O-18 of precipitation (meteoric water) decreases proportionally as elevation increases. Knowing the formation temperature and delta O-18 of carbonate, we can trace back to the precise value of delta O-18 in precipitation, and then, using the theoretical model, or empirical relationship, between the delta O-18 of precipitation and elevation, reconstruct paleoelevation. Furthermore, clumped isotope thermometry can be used to test for diagenetic effects on pedogenic samples to ensure they retain original sedimentary isotopic compositions. We summarized previous applications of carbonate clumped isotope thermometry to accurately and precisely reconstruct the paleoelevation of the Andes mountains, Western North America and the Tibetan Plateau to provide insights into the uplift history and geodynamic process of those regions. Despite the great potential for carbonate clumped isotopes in paleoelevation reconstruction, there are still challenges regarding equilibrium mechanisms, the discrepancies between different calibrations and the broader application in different carbonates. To resolve these challenges, more theoretical research is needed, as well as improving the resolution of IMRS.
关键词	LUNPOLA BASIN CENTRAL ANDES ACID FRACTIONATION MIOCENE ELEVATION TIBETAN PLATEAU C-13-O-18 BONDS SOUTHERN TIBET SURFACE UPLIFT NORTHERN TIBET TEMPERATURE
英文关键词	carbonate clumped isotope; Delta 47; paleothermometer; paleoelevation
语种	英语
WOS研究方向	Science & Technology - Other Topics
WOS类目	Multidisciplinary Sciences
WOS记录号	WOS:000496452900007
来源期刊	CHINESE SCIENCE BULLETIN-CHINESE
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259415
推荐引用方式 GB/T 7714	Xiong, Zhongyu,Ding, Lin,Xie, Jing. Carbonate clumped isotope (Delta(47)) thermometry and its application in paleoelevation reconstruction[J]. 中国科学院青藏高原研究所,2019,64(16).
APA	Xiong, Zhongyu,Ding, Lin,&Xie, Jing.(2019).Carbonate clumped isotope (Delta(47)) thermometry and its application in paleoelevation reconstruction.CHINESE SCIENCE BULLETIN-CHINESE,64(16).
MLA	Xiong, Zhongyu,et al."Carbonate clumped isotope (Delta(47)) thermometry and its application in paleoelevation reconstruction".CHINESE SCIENCE BULLETIN-CHINESE 64.16(2019).