贵州青岩地区中三叠统新苑组碳酸盐岩碳氧同位素特征及古环境意义  

The C and O Isotopic Characteristics and Paleoenvironmental Significance of Carbonate Rocks of Middle Triassic Xinyuan Formation of Qingyan,Guizhou

作　　者：宁秋实[1] 喻美艺[1] 

机构地区：[1]贵州大学资源与环境学院,贵州贵阳550025

出　　处：《贵州地质》2016年第1期71-76,共6页Guizhou Geology

基　　金：国家自然科学基金项目(No.40830211):中生代初的生物环境事件与海洋生态系的重建

摘　　要：对青岩地区中三叠统新苑组营上坡段和雷打坡段碳酸盐岩进行了碳氧同位素分析。δ(13CPDB)值介于-0.65‰3.65‰,均值为1.24‰;δ(18OPDB)值介于-5.50‰-1.70‰,均值为-3.09‰。研究表明,营上坡段沉积时期是海平面上升,还原性增强,具有海洋生产力高和生物量富集的特点,温度先降低后升高、盐度整体趋于增大。雷打坡段沉积时期为温度逐渐升高、盐度逐渐降低。在雷打坡下段和中段沉积时期海平面几乎不变,海洋生产力较稳定;上段沉积时期是海平面下降,氧化性增强,其海洋生产力较低、生物贫乏。In this paper,carbon and oxygen isotope of carbonate rocks samples collected from middle triassic Yingshangpo and Leidapo segment at Qingyan was analysed. The δ（13CPDB） is between- 0. 65‰ to 3.65‰,and the average is 1. 24‰. The δ（18OPDB） is between- 5. 50‰ to- 1. 70‰,and the average is 3.09‰. The researches show that the sea level rised with strong reducible,the marine productivity and the biomass is high at Yingshangpo sedimentation period. In this area,the temperature decreased first and then raised,the salinity tended to increase. The temperature gradually raised and the salinity was decreased at Leidapo sedimentation period. The sea level was almost the same and the marine productivity was stable at middle and lower segment of Leidapo sedimentation period. The sea level and marine productivity dropped and lacked of organisms,the oxidation increased at the upper segment of Leidapo sedimentation period.

关 键 词：碳氧同位素 新苑组 古环境 贵州青岩 

分 类 号：P597.2[天文地球—地球化学]