石油实验地质
石油實驗地質
석유실험지질
EXPERIMENTAL PETROLEUM GEOLOGY
2013年
3期
320-324
,共5页
路清华%邵志兵%贾存善%岳勇%刘少杰
路清華%邵誌兵%賈存善%嶽勇%劉少傑
로청화%소지병%가존선%악용%류소걸
碳同位素%轻烃%生物标志化合物%地球化学%奥陶系%玉北地区%塔里木盆地
碳同位素%輕烴%生物標誌化閤物%地毬化學%奧陶繫%玉北地區%塔裏木盆地
탄동위소%경경%생물표지화합물%지구화학%오도계%옥북지구%탑리목분지
carbon isotope%light hydrocarbon%biomarker%geochemistry%Ordovician%Yubei area%Tarim Basin
玉北地区鹰山组原油为低凝固点、含硫、高蜡的中质油,饱和烃色谱正构烷烃分布完整,但色谱基线出现不同程度抬升,且原油非烃和沥青质碳同位素偏轻,族组分碳同位素发生倒转,表明该区原油经历了至少2期成藏过程,早期充注原油遭受生物降解作用后又与后期充注的高成熟原油相混合.地化分析主要表现为后期充注原油特征:弱植烷优势(Pr/ Ph≤1.0),较高含量的伽马蜡烷(G/ C30藿烷为0.24~0.4)及 C35升藿烷/ C34升藿烷>1.0的“翘尾巴式”特征,表明后期原油主要来源于还原—强还原生烃环境;正庚烷含量为46.47%~48.57%,C23-三环萜烷优势,较高的三环萜烷/藿烷,指示其生油母质为菌藻类;较高的庚烷值及四甲基萘指数表明原油处于高成熟演化阶段,推测来源于寒武系烃源岩.
玉北地區鷹山組原油為低凝固點、含硫、高蠟的中質油,飽和烴色譜正構烷烴分佈完整,但色譜基線齣現不同程度抬升,且原油非烴和瀝青質碳同位素偏輕,族組分碳同位素髮生倒轉,錶明該區原油經歷瞭至少2期成藏過程,早期充註原油遭受生物降解作用後又與後期充註的高成熟原油相混閤.地化分析主要錶現為後期充註原油特徵:弱植烷優勢(Pr/ Ph≤1.0),較高含量的伽馬蠟烷(G/ C30藿烷為0.24~0.4)及 C35升藿烷/ C34升藿烷>1.0的“翹尾巴式”特徵,錶明後期原油主要來源于還原—彊還原生烴環境;正庚烷含量為46.47%~48.57%,C23-三環萜烷優勢,較高的三環萜烷/藿烷,指示其生油母質為菌藻類;較高的庚烷值及四甲基萘指數錶明原油處于高成熟縯化階段,推測來源于寒武繫烴源巖.
옥북지구응산조원유위저응고점、함류、고사적중질유,포화경색보정구완경분포완정,단색보기선출현불동정도태승,차원유비경화력청질탄동위소편경,족조분탄동위소발생도전,표명해구원유경력료지소2기성장과정,조기충주원유조수생물강해작용후우여후기충주적고성숙원유상혼합.지화분석주요표현위후기충주원유특정:약식완우세(Pr/ Ph≤1.0),교고함량적가마사완(G/ C30곽완위0.24~0.4)급 C35승곽완/ C34승곽완>1.0적“교미파식”특정,표명후기원유주요래원우환원—강환원생경배경;정경완함량위46.47%~48.57%,C23-삼배첩완우세,교고적삼배첩완/곽완,지시기생유모질위균조류;교고적경완치급사갑기내지수표명원유처우고성숙연화계단,추측래원우한무계경원암.
@@@@The Ordovician oil in Yubei area has middle density, low freezing point and high waxy content. The distribution of normal alkane is complete while the baseline of saturated hydrocarbon chromatogram shows various degrees of excursion. It shows upside-down phenomenon that the δ13 C value of nonhydrocarbon and asphaltene is smaller than that of saturated and aromatic hydrocarbon. All of these indicate that the reservoir underwent no less than two periods of oil charging. The early charging oil experienced strong biodegradation and mixed with the lat-er higher mature charging oil. Geochemical properties are mainly attributed to the late charging oil with weak phytane predominance (Pr/ Ph≤1. 0), abundance of gammacerne (G/ C30 -hopanes 0. 14-0. 24), and higher C35-hopane / C34-hopane value ( >1. 0) characteristics, showing reduction-strong reduction sedimentary envi-ronment. The predominance of n-heptane (46. 47% -48. 57% ), and C23-tricyclic terpane and higher tricyclic terpane / hopane indicate that the original source materials of later oil are homonemeaes. High heptane value and tetramethylnaphthalene index suggest that the oil is in high mature stage and probably generated from the Cambri-an source rock.