柴达木盆地第三系芳烃的地球化学─—二环芳烃与多环芳烃的关系

GEOCHEMISTRY OF THE TERTIARY AROMATIC HYDROCARBONS IN THE QAIDAM BASIN──RELATIONSHIP BETWEEN DICYCLIC AND POLYCYCLIC AROMATIC HYDROCARBONS

妥进才

Tuo Jincai

中国科学院兰州地质研究所, 730000

Lanzhou Research Institute of Geology, Academia Sinica

柴达木盆地西部第三系系半咸水一咸水湖盆沉积产物.西部的狮子沟盐湖从下第三系古一始新世开始,一直延续至上第三系中新世,以半咸水一咸水湖相为主.南翼山地区的盐湖则从渐新世开始到上新世消亡.主要的生油凹陷发育期是以微咸水一半咸水湖相沉积为主的中新世和上新世.有机地球化学研究表明,西部第三系生油岩有机质类型主要以混合型为主,兼有部分腐泥型和腐殖型.从二环芳烃与多环芳烃的变化关系及芳烃化合物与沉积环境和母源输入的关系来看,芳烃馏份中的蔡系、联苯系、惹烯等化合物与陆源高等植物之间存在着成因联系.而菲系、窟系以及苯并花和苯并蔡唆吩则可能与低等水生生物的关系更为密切.此外,有利于形成药系和硫药系列化合物的咸水还原环境,同样也有利于蔡系化合物的保存.

The Tertiary of the West Qaidam Basin was deposited in the environment of a brackish-salt lake basin.The Shizigou saline lake in the west existed from the Paleocene-Eoceneto the Miocene and was dominated by brackish-salt water lake factes,while the saline lake in Nanyishan area existing from the Oligocene to the Pliocene.The developing period of main oil-generating depressions is the Miocene and the Pliocene dominated by the deposit of brackish lake factes.Studies on organic geochemistry show that the organic matter of the Tertiary oil-generating rocks in the west is mainly mix-typed,and part of it belongs to sapropel and humic types.Judged by the'changing relationship of dicyclic aromatic hydrocarbons to polycyclic ones and the relationship of aromatic hydrocarbon compounds to sedimentary environment and mother rock inputs,there is genetic relationship between the naphthalene series,biphenyl series,retene and other compounds in aromatic hydrocarbon fractions and higher terrigenous plants.But phenanthrene series,chrysene series,benzopyren and benzonaphthalene thiophene probably have closer relationship to lower hydrobios.In addition,salt water reduction environment advantageous to the formation of fluorene series and sulfur fluories compounds is also advantageous to the preservation of naphthalene series compounds.

国家自然科学基金资助项目

https://doi.org/10.11781/sysydz199604406