Features of gas released from heated igneous rock, Tarim Basin
-
摘要: 采用加热释气法对塔里木盆地塔北和塔中地区二叠系火成岩中所含流体特征进行了研究,以揭示与岩浆活动相伴生的深部来源流体的特征。塔中地区2个火成岩样品释气总量分别为1 902.7μL/g和1 517.7μL/g,塔北地区5个样品释气总量在515.2～691.5μL/g之间;塔中地区火成岩中流体含量显著高于塔北地区。无论塔中和塔北地区,气体释放量都在中温阶段(700℃)达到高峰。CO2为火成岩所释放气体中最主要的组成部分,在每个样品的每个温度阶段都有较高的含量,最高可达91.47%;N
2和SO2也是所释放气体中的主要组成部分,在部分样品中含量较高;所释放气体中都或多或少含有一定量的CO,H2及烃类气体、稀有气体等组分。火山岩所释放气体的40Ar/36Ar值较高,在450.3～1 170.3之间,反映了深源的特点。但气体中3He/4He值除一个辉绿岩样品较高(0.35Ra)外,其他的都较低,位于0.0091～0.091Ra之间,具有壳源的特征;其原因是火成岩所包裹的He与地壳He发生了相互扩散而混合。 Abstract: The fluid entrapped in Permian igneous rocks collected from the north and the center of the Tarim Basin has been studied using heating method so as to analyze the features of fluid from deep strata.The total amounts of gas released from the 2 igneous rock samples collected in the central Tarim region are 1 902.7 μL/g and 1 517.7 μL/g,much higher than those of the 5 igneous rock samples collected in the northern Tarim region(515.2-691.5μL/g).In both the central and the northern Tarim regions,gas release amounts reach a peak during the medium temperature stage(700℃).CO2 is the dominant compound in released gas from each sample during each temperature stage,and reaches as high as 91.47%.N2 and SO2 are also important compounds in released gas,and have high contents in some samples.CO,H2,hydrocarbon and noble gas are found in released gas more or less.The 40Ar/36Ar ratios of released gas are high,usually between 450.3 and 1 170.3,indicating deep source.However,the 3He/4He ratios of released gas are low(0.0091-0.091Ra) except for one diabase sample(0.35 Ra),indicating crust source.The reason is that He in igneous rocks mixes with that in crust due to diffusion effect. -
Key words:
- noble gas /
- gas released by heating /
- deep fluid /
- igneous rock /
- Tarim Basin
-
[1] 戴金星,宋岩,戴春森,等.中国东部无机成因气及其气藏形成条件[M].北京:科学出版社,1995. [2] 李先奇,戴金星.中国东部二氧化碳气田(藏)的地化特征及成因分析[J].石油实验地质,1997,19(2):215-221. [3] 金之钧,朱东亚,胡文瑄,等.塔里木盆地热液活动地质地球化学特征及其对储层影响[J].地质学报,2006,80(2):245-253. [4] 朱东亚,金之钧,胡文瑄,等.塔里木盆地深部流体对碳酸盐岩储层影响[J].地质论评,2008,54(3):348-354. [5] 吕修祥,杨宁,解启来,等.塔中地区深部流体对碳酸盐岩储层的改造作用[J].石油与天然气地质,2005,26(3):284-289,296. [6] 钱一雄,陈跃,陈强路,等.塔中西北部奥陶系碳酸盐岩埋藏溶蚀作用[J].石油学报,2006,27(3):47-52. [7] 张铭杰,王先彬,李立武.对幔源岩中流体组成的不同测定方法评价[J].地质论评,2000,46(2):160-166. [8] 刘刚,王先彬,李立武.张家口大麻坪碱性玄武岩内地幔岩包体气体成分的初步研究[J].科学通报,1996,41(19):1775-1777. [9] Javoy M,Pineau F.The volatiles records of a "popping"rock form the Mid-Atlantic Ridge at 14°N:Chemical and isotopic compositions of gas trapped in the vesicles[J].Earth and Planetary Science Letters,1991,107(3-4):598-611. [10] Pineau F,Mathez E A.Carbon isotopes in xenoliths from the hualalai volcano,Hawaii,and the generation of isotopic variability[J].Geochimica et Cosmochimica Acta,1990,54(1):217-227. [11] 李立武,刘刚,王先彬.幔源岩流体包裹体气态物质组成质谱分析[J].质谱学报,1998,19(3):25-27. [12] 叶先仁,吴茂炳,孙明良.岩矿样品中稀有气体同位素组成的质谱分析[J].岩矿测试,2001,20(3):174-178. [13] 马锦龙,陶明信.郯庐断裂带中段幔源岩包体中的流体组成特征[J].兰州大学学报:自然科学版,2004,40(1):85-89. [14] 张铭杰,王先彬,刘刚,等.中国东部新生代碱性玄武岩及幔源捕虏体中的流体组成[J].地质学报,1999,73(2):162-166. [15] 胡桂兴,王先彬,文启木.原始太阳一星云条件下Fischer-Tropsch反应中的碳同位素分馏[J].中国科学D辑:地球科学,1997,27(5):395-400. [16] 王先彬.稀有气体同位素地球化学和宇宙化学[M].北京:科学出版社,1989:153-220. [17] Staudacher T,Kurz M D,Allegre C J.New noble gas data on glass samples from Loihi Seamount and Hualalai and on dunite samples from Loihi and Reunion Island[J].Chemical Geology,1986,56(3-4):193-205. [18] Moreira M,Kurz J,Allegre C J.Rare gas systematics in Popping Rock:Isotopic and elemental compositions in the upper mantle[J].Science.1998,279(5354):1178-1181. [19] Staudacher T,Sarda P,Allegre C J.Noble gas systematics of Reunion Island,Indian Ocean[J].Chemical Geology,1990,89(1-2):1-17. [20] 孙省利,陈践发,郑建京,等.塔里木盆地寒武系底部硅质岩的稀有气体同位素组成特征[J].中国科学D辑:地球科学,2008,38(S2):105-109. -
点击查看大图
计量
- 文章访问数: 2726
- HTML全文浏览量: 34
- PDF下载量: 821
- 被引次数: 0
下载:
苏公网安备32021102000780号