Present-day temperatures of magma chambers in the crust beneath Ninger volcanic field, southwestern China: Estimation from CO2-CH4 carbon isotope geothermometer
文献类型：期刊论文
| 作者 | Zhao CiPing1; Wang Yun1; Zhou Zhi1; Li ZhongPing2; Xing LanTian2 |
| 刊名 | ACTA PETROLOGICA SINICA
 |
| 出版日期 | 2017 |
| 卷号 | 33期号:1页码:231-249 |
| 关键词 | Magma Temperature Carbon Isotopic Geothermometer Co2 And Ch4 Thermal Spring Gases Ninger Volcanic Field |
| ISSN号 | 1000-0569 |
| 文献子类 | Article |
| 英文摘要 | Temperature is an important physical parameter of magma. To access and monitor temperature parameter of magma favors better understanding variations of the physical and chemical properties and behavior of magma, the evaluation of activity and eruption risk of a volcano. Volcanic magma and hydrothermal system enrich carbon bearing gases. Therefore the carbon isotopic thermometers can be employed to acquire the magma temperature of subsurface dormant volcano. Here we conduct 2 years of continuous and 2 times of parallel observation on carbon isotope composition of CO2 and CH4 of 4 thermal springs in highest strength of ground geothermal anomaly area in Ninger Volcanic Field (NVF). Using observational data, we identify whether CO2 and CH4 gases come from magma, and judge whether carbon isotope fractionation between CO2 and CH4 attain equilibrium. Using Horita CO2-CH4 carbon isotope equilibrium fractionation equation we calculate the source temperature of volcanic gases escape from the NVF. Our results show that, of 4 thermal springs in NVF, CO2 and CH4 from 1 are of non-magmatic origin, but that from the other 3 are mainly of magmatic origin, and that after excluding non-magmatic origin data, carbon isotope fractionation between CO2 and CH4 of the rest data attain equilibrium according delta-Delta plot method, and that gases source temperature of CO2 and CH4 of these 3 thermal springs are 425 similar to 475 degrees C, 941 similar to 995 degrees C and 1179 similar to 1578 degrees C, respectively. Combining our data and the uppermost crust temperature field results, we conclude that, there exist 2 magma chambers in NVF at present day, which located south to Ninger Volcano and north to Tongguan Volcano, respectively, that the temperature of Ninger magma chamber is up to 1179 similar to 1578 degrees C, that of Tongguan magma chamber, 941 similar to 995 degrees C, which reach to rhyolite (600 similar to 900 degrees C), andesites (800 similar to 1100 degrees C) and the basaltic magma (1000 similar to 1250 degrees C) formation temperature, and that intensive magnitude 6 earthquake cluster activity in space in Simao-Puer seismic zone can be explained by stronger activity level of Ninger magma chamber. The delta-Delta plot guidelines of determining the carbon isotope fractionation equilibrium between CO2 and CH4 should be amended as follows: under the conditions that the sign of the slope of the two fitting lines keep always opposite, the delta C-13(CO2) Delta(CO2-CH4) fitting straight line and the delta(13) C-CH4-Delta(CO2-CH4) one should intersect near the delta-axis with intercept difference Delta(b) <= 0.16. |
| WOS关键词 | EQUATION-OF-STATE ; MOLECULAR-DYNAMICS SIMULATION ; SATSUMA-IWOJIMA ; HYDROTHERMAL SYSTEMS ; CH4-CO2-H2O SYSTEM ; GAS-DISCHARGES ; 10 GPA ; CO2 ; METHANE ; CH4 |
| WOS研究方向 | Geology |
| 语种 | 英语 |
| WOS记录号 | WOS:000393257900019 |
| 出版者 | SCIENCE PRESS |
| 源URL | [http://ir.iggcas.ac.cn/handle/132A11/53105]  |
| 专题 | 地质与地球物理研究所_兰州油气中心 |
| 通讯作者 | Zhao CiPing |
| 作者单位 | 1.Earthquake Adm Yunnan Prov, Kunming 650124, Peoples R China 2.Chinese Acad Sci, Inst Geol & Geophys, Lanzhou Ctr Oil & Gas Resources, Lanzhou 730000, Peoples R China |
| 推荐引用方式 GB/T 7714 | Zhao CiPing,Wang Yun,Zhou Zhi,et al. Present-day temperatures of magma chambers in the crust beneath Ninger volcanic field, southwestern China: Estimation from CO2-CH4 carbon isotope geothermometer[J]. ACTA PETROLOGICA SINICA,2017,33(1):231-249. |
| APA | Zhao CiPing,Wang Yun,Zhou Zhi,Li ZhongPing,&Xing LanTian.(2017).Present-day temperatures of magma chambers in the crust beneath Ninger volcanic field, southwestern China: Estimation from CO2-CH4 carbon isotope geothermometer.ACTA PETROLOGICA SINICA,33(1),231-249. |
| MLA | Zhao CiPing,et al."Present-day temperatures of magma chambers in the crust beneath Ninger volcanic field, southwestern China: Estimation from CO2-CH4 carbon isotope geothermometer".ACTA PETROLOGICA SINICA 33.1(2017):231-249. |
入库方式： OAI收割
来源：地质与地球物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。