中国煤炭地质
中國煤炭地質
중국매탄지질
COAL GEOLOGY OF CHINA
2014年
7期
15-20,32
,共7页
龙潭组%微量元素%沉积环境%沉积相%盘县土城向斜
龍潭組%微量元素%沉積環境%沉積相%盤縣土城嚮斜
룡담조%미량원소%침적배경%침적상%반현토성향사
Longtan Formation%trace element%sedimentary environment%sedimentary facies%Tucheng syncline,Panxian
为探讨盘县土城向斜龙潭组物源及沉积环境,对ZK402号孔龙潭组样品进行微量元素及稀土元素测试分析,结果显示:龙潭期的水体为微咸水-半咸水的淡水环境,水体分层不强的厌氧环境-水体分层及底层水体呈现H2S的厌氧环境;泥岩中稀土含量高,源岩主要为钙质泥岩和碱性玄武岩。根据砂岩粒度分析、薄片鉴定、电子探针等综合分析,在龙潭组中识别出三角洲和障壁砂坝-潟湖沉积相以及三角洲前缘、下三角洲平原、上三角洲平原、潮坪、潟湖等亚相,龙潭早、晚期以潟湖相为主,龙潭中期以分流河道和分流间湾广泛发育为特征。
為探討盤縣土城嚮斜龍潭組物源及沉積環境,對ZK402號孔龍潭組樣品進行微量元素及稀土元素測試分析,結果顯示:龍潭期的水體為微鹹水-半鹹水的淡水環境,水體分層不彊的厭氧環境-水體分層及底層水體呈現H2S的厭氧環境;泥巖中稀土含量高,源巖主要為鈣質泥巖和堿性玄武巖。根據砂巖粒度分析、薄片鑒定、電子探針等綜閤分析,在龍潭組中識彆齣三角洲和障壁砂壩-潟湖沉積相以及三角洲前緣、下三角洲平原、上三角洲平原、潮坪、潟湖等亞相,龍潭早、晚期以潟湖相為主,龍潭中期以分流河道和分流間灣廣汎髮育為特徵。
위탐토반현토성향사룡담조물원급침적배경,대ZK402호공룡담조양품진행미량원소급희토원소측시분석,결과현시:룡담기적수체위미함수-반함수적담수배경,수체분층불강적염양배경-수체분층급저층수체정현H2S적염양배경;니암중희토함량고,원암주요위개질니암화감성현무암。근거사암립도분석、박편감정、전자탐침등종합분석,재룡담조중식별출삼각주화장벽사패-석호침적상이급삼각주전연、하삼각주평원、상삼각주평원、조평、석호등아상,룡담조、만기이석호상위주,룡담중기이분류하도화분류간만엄범발육위특정。
To explore Longtan Formation provenance and sedimentary environment carried out trace elements and rare earth elements testing analysis for Longtan Formation samples from borehole ZK402. The result has shown that the water body Longtan Formation de-posited was in brackish water-fresh water environment, not obviously stratified anaerobic environment-stratified with bottom layer presented H2S anaerobic environment;high rare earth elements content in mudstone, source rocks mainly have calcareous mudstone and alkali basalt. Based on integrated analyses of sandstone grain-size, thin section authentication, electron probe etc., have identified delta and barrier bar-lagoon sedimentary facies and delta front, lower delta plain, upper delta plain, tidal flat, lagoon subfacies. Dur-ing early and later stages of Longtan Formation were mainly lagoon facies, middle stage characterized by widely developed distributary channel and interdistributory bay.