【作者】 刘东鹰；

【导师】 彭平安；

【作者基本信息】 中国科学院研究生院（广州地球化学研究所） ， 地球化学， 2004， 博士

【摘要】 江苏下扬子区位于淮阴—响水断裂、郯庐断裂东南，指具有扬子型海相沉积分布的江苏省中南部地区。大地构造位置位于扬子板块东部的下扬子区的东部。勘探面积约7.7万平方千米。该区经历多期构造活动改造，海相中、古生界构造变形极为复杂。本文应用多种地球化学方法，研究了海相中、古生界的生烃演化特征、油气显示的分带和来源、剖析了油气藏的特征和成藏期次、探讨了油气藏的控制因素等，取得了如下主要认识： 海相中、古生界烃源岩经历了多期构造运动，形成了多期生烃过程。通过采用裂变径迹、镜质体发射率、包裹体温度、粘土矿物演化特征等多种分析手段，建立了多旋回演化区复杂的埋藏史模型，在此基础上，恢复了烃源岩多期生烃历史。全区累计生油146.23亿吨，生气6379.19千亿方，合计6525.42(亿吨，千亿方)。阶段生烃增长量最多的是志留纪，其次晚白垩世、石炭-二叠纪、寒武—奥陶纪、三叠纪、早第三纪，分别为总生烃量的39.3％、14.5％、14.3％、11％、10.5％、9％。其中晚期生烃占总生烃量的1／4。下古生界烃源岩晚期生烃强度大的地区分布在苏北一带，上古生界烃源岩晚期生烃强度大的地区分布在句容—海安一带。 海相中、古生界油气显示宏观上可分为南带沥青显示，中带轻质油、烃类气、二氧化碳气显示和北带普通重质油、烃类气显示。利用碳同位素、生物标记化合物、成熟度特征对比认为南带沥青显示分别来自下志留-中上奥陶统、中上寒武统、下寒武统和震旦系三套同位素分布有异的源岩；中带油及油显示主要来自下三叠统青龙组和二叠系源岩；北带油和油显示主要来自第三系源岩，盐城气的源岩为下二叠统栖霞组。南、中、北带的不同类型的显示分别对应下古生界早期生烃中心、上古生界晚期生烃中心和第三系生烃凹陷区。 应用包裹体分析技术，确定了本区典型油气藏的成藏期次。句容地区油藏为一次成藏，油藏成藏期为90Ma左右。这一时期正是上古生界烃源岩大量生烃时期，油气运移活跃，生、储、盖配套关系良好。盐城朱家墩气藏天然气充注有两期，第一期为三垛组沉积时期，该期天然气充注较弱，油气包裹体含量少；第二期为盐城组沉积时期，是气藏的主要成藏期，油气包裹体含量高。黄桥气藏有三期充注过程，第一期在90Ma左右，油气充注为主；第二期在60Ma左右，油气充注为主，并伴有二氧化碳期运移成藏现象；第三次充注在25Ma左右，二氧化碳气充注，并驱替了早期的烃类。成藏期次分析表明，本区现存的油气藏成藏期晚，均在晚白垩纪以后，说明晚期成烃、成藏对本区油气勘探具有现实意义。 在分析了生烃演化过程、油气显示及油气藏特征的基础上，研究了油气藏类型、形成阶段，探讨了油气成藏控制因素，认为与海相中、古生界有关的油气藏类型多样，有古生古储(自生自储)型、古生新储(下生上储)型和新生古储型三大类。油气藏成藏分两个阶段，加里东期—印支期前的油气藏成藏阶段和晚燕山—喜山期的油气藏成藏阶段，其中后一阶段形成的油气藏具有现实意义。油气成藏的主要控制因素包括三个方面：一是印支—早燕山运动对早期形成的油气藏起破坏作用；二是生烃中心控制油气藏的分布，晚期生烃中心具有重要意义；三是陆相中新生界覆盖对现存油气藏保存具有重要作用。 本文应用多种方法对江苏下扬子区海相中、古生界的油气成藏特征和控制因素进行系统研究、探讨，在油气来源、油气藏形成期次及油气分布规律和控制因素等方面取得了一系列新的认识，对该区的油气勘探具有重要的指导意义，同时对我国南方海相油气藏的成藏研究具有借鉴作用。更多还原

【Abstract】 Jiangsu lower Yangtze area is in the southeast of Huaiyin-Xiangshui and Tanlu fracture, and the area have sea facies aggradation distributing in middle and south of Jiangsu Province. In tectonic framework, it is in the east of the lower Yangtze area of the east of the Yangtze plate. The exploration acreage is about 77,000 km2. The area had come through many times reformation of tectonic cycle, the tectonic distortion of marine facies Mesozoic group and Proterozoic erathem were very intricate. The article used multi-method of geochemistry to research character of making hydrocarbon and evolvement of marine facies Mesozoic group and Proterozoic erathem, and distributing and source of oil and gas show, and took apart pool character and a period of time, and discussed control factor of pool, and etc. We obtained as follows main cognition:Marine facies Mesozoic group and Proterozoic erathem oil source rock came through many times tectonic movement, and formed many times course of making hydrocarbon. We got across many analyse artifice , for example fission track , vitrinite reflectance ratio, inclusion temperature , the evolvement character of clay mineral etc, and created complex imbed history in many gyration evolvement area. According as these, we resume many times making hydrocarbon history of oil source rock. The whole area accumulative total maked 14,623 bill ton oil, and 637,919 thousand bill square gas , add up 652,542(bill ton, thousand bill square). Most of phase making hydrocarbon quantity is Silurian period, the second is Late Cretaceous, Carboiferous to Permian , Cambrian to Ordovician, Triassic, early Tertiary, every part is 39.3%,14.5%,14.3%,11%,10.5%,9% of total making hydrocarbon quantity. Thereinto, afternoon is quarter of all. The larger area of the lower Proterozoic erathem making hydrcarbon intension is in Subei . The larger area of the higher Proterozoic erathem making hydrcarbon intension is in Jurong-Haian.Oil & gas show of marine facies Mesozoic group and Proterozoic erathem in macroscopy can set off show cincture that asphaltum in south, light oil & hydrocarbon gas & CO2 in middle, general weighty & gas in north. Using carbon isotopes and organism sign compound and character of maturity to compare, we think that asphaltum show in south cincture is from three set source rock of different carbon isotopes-lower Silurian to middle and upper Ordovician, middle and upper Cambrian lower Cambrian & Sinian; oil & oil show in middle is from source rock of Qinglong formation of lower Triassic and Permian: oil & oil show in north is from source rock of tertiary, the source rock of Yanchcng ga.; is from Qixia formation of lower Permian. The different type in south, middle and north fit separate makinghydrocarbon center from forepart in lower Proterozoic erathenu afternoon in upper Proterozoic erathem and indentation in tertiary.Using inclusion analysis technology, we made sure times of representative pool in this area. Jurong pool is once-form, the time is about 90Ma. The time just grow hydrocarbon fastigium in upper Proterozoic erathem, oil & gas move active, and have good collocate relationship. Zhujiadun natural gas store have two times to immit, firstly is Sanduo formation sediment time that natural gas immit less and have little inclusion; secondly is Yancheng formation sediment time that is gas store main form time and have much inclusion. Huangqiao gas store have three times to immit,firstly is in about 90Ma that mostly immit oil & gas; secondly is in about 60Ma that mostly immit oil & gas and have CC moving and form store; the third is in about 25Ma that CC2 immit and drive out early hydrocarbon. The result of analysis form store’s times, the area’s oil & gas store of preserving now were form later, after late Cretaceous at all, these ideas explain that hydrocarbon and store form later is important to prospect for this area and have real sense.The base on analysis course of making hydrocarbon and evolvement> oil & gas show and character of oil & gas store, after we researched the type of更多还原