Geochemical Characteristics of Saturated Hydrocarbons from Strata Inferred from the Multitubular Cores of the Prydz Bay and the Sources/Environmental Variations  

作　　者：Yang Dan Zhang Yicheng Han Xinbin Zhao Jun Xu Xuedan Zhang Huijuan Zhang Haisheng 

机构地区：[1]Key Laboratory of Marine Ecosystem and Biogeochemistry,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China [2]Key Laboratory of Submarine Geosciences,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China

出　　处：《Meteorological and Environmental Research》2019年第5期96-102,共7页气象与环境研究（英文版）

基　　金：Supported by Special Project for Comprehensive Survey and Assessment of the Environment in the Arctic and Antarctic(CHINARE2012-01-02,CHINARE2013-01-02,CHINARE2013-04-01);National Natural Science Foundation of China(41576186,41106046,41306202);Special Funds for Basic Scientific Research of Second Institute of Oceanography,State Oceanic Administration(JT1309)

摘　　要：The content and distribution of saturated hydrocarbons (n-alkanes,isoprenoid,steranes and terpanes) in the multitubular cores ANT29-M2 from the Prydz Bay of the Antarctic were analyzed using gas chromatography-mass spectrometry,and the organic matter sources,sedimentary environments and geochemical parameters of the sediments were discussed.The results showed that the carbon number of the multitubular samples ANT29-M2 was between C14 and C32 with low-carbon single peak group and main peak carbon of C18 .n-alkane gas charomatography fingerprint spectra indicated that unmixable complex compounds displayed a significant bulge,and the obvious UCM shape suggested a large input of bacteria.The ∑C21^-/∑C22^+ values varied from 1.82 to 3.9,and C21^+C22 /C28 ^+C 29 values ranged from 1.26 to 6.30,indicating that the sedimentary organic matter mainly originated from marine algae.The CPI and OEP values varied from 1.54 to 2.29 and from 4.48 to 4.82,respectively,with a significant odd even predominance.Pr/Ph values ranged from 0.34 to 0.76,significantly smaller than 1,with a clear distribution of C29 >C27 >C28 and C27 >C29 >C28 for regular steranes and a V-shaped C29 predominance and C27 predominance.This indicated that the sedimentary organic matter in the Prydz Bay originated from a mixed marine/continental source,and was deposited under a strongly reducing environment.The maturity parameters of the sedimentary strata from the Prydz Bay displayed significant inconsistency.Geochemical parameters of hopane C 32 22S/C 32 (22S+22R) and sterane C 29 αββ/(αββ+ααα) suggested a high maturity,but other geochemical parameters such as C29 ααα20S/C29 ααα(20S+20R),CPI and OEP reflected that those of columnar strata were within the range of modern marine sediments (lowly mature to immature),probably resulting from the development of microorganisms.The content and distribution of saturated hydrocarbons（n-alkanes,isoprenoid,steranes and terpanes） in the multitubular cores ANT29-M2 from the Prydz Bay of the Antarctic were analyzed using gas chromatography-mass spectrometry,and the organic matter sources,sedimentary environments and geochemical parameters of the sediments were discussed. The results showed that the carbon number of the multitubular samples ANT29-M2 was between C14 and C32 with low-carbon single peak group and main peak carbon of C18. n-alkane gas charomatography fingerprint spectra indicated that unmixable complex compounds displayed a significant bulge,and the obvious UCM shape suggested a large input of bacteria.The ∑C21-/∑C22+ values varied from 1. 82 to 3. 9,and C21+ C22/C28+ C29 values ranged from 1. 26 to 6. 30,indicating that the sedimentary organic matter mainly originated from marine algae. The CPI and OEP values varied from 1. 54 to 2. 29 and from 4. 48 to 4. 82,respectively,with a significant odd even predominance. Pr/Ph values ranged from 0. 34 to 0. 76,significantly smaller than 1,with a clear distribution of C29> C27> C（28） and C27> C29> C（28） for regular steranes and a V-shaped C29 predominance and C27 predominance. This indicated that the sedimentary organic matter in the Prydz Bay originated from a mixed marine/continental source,and was deposited under a strongly reducing environment. The maturity parameters of the sedimentary strata from the Prydz Bay displayed significant inconsistency. Geochemical parameters of hopane C3222 S/C32（22 S +22 R）and sterane C29αββ/（αββ + ααα） suggested a high maturity,but other geochemical parameters such as C29ααα20 S/C29ααα（20 S +20 R）,CPI and OEP reflected that those of columnar strata were within the range of modern marine sediments（lowly mature to immature）,probably resulting from the development of microorganisms.

关 键 词：PRYDZ BAY Sediment CORES Saturated hydrocarbons GEOCHEMICAL characteristics Environmental significance 

分 类 号：P[天文地球]