中文摘要：

通过对南方海相层系多种烃源（烃源岩、固体沥青、沥青砂岩、原油/油苗）、天然气相关模拟实验及地球化学分析,发现海相层系存在多种烃源共存且相互转化、连续或叠置生烃特征,尤其南方海相烃源岩普遍存在生气母质的物质状态转换和生烃过程与贡献的接替,呈现出＂多源复合、多阶连续＂的天然气形成演化特点。根据母质继承效应、同位素分馏效应及累积效应,构建了以稳定同位素组成为基础,以组分、生物标志化合物、轻烃、非烃气体和稀有气体同位素、微量元素为重要手段的不同形式烃源转化成烃过程的示踪指标体系,可以示踪不同形式烃源转化成烃过程。进一步完善了天然气形成、成藏的三元示踪体系,提出了气源岩时代模型公式以及气-源对比、成因判识指标及其示踪,初步建立混源气识别及混源比例定量判识模型。

英文摘要：

Simulated experiments and geochemical analyses of different types of hydrocarbon sources （source rocks,solid bitumen,asphaltic sandstone,crude oil/oil seepages） in marine sequences of South China reveal the coexistence of multiple hydrocarbon sources and their mutual transformation and continuous or overlapping hydrocarbon generation.Marine source rocks in South China commonly feature in a state conversion of gas-generating parent materials and a relay of hydrocarbon generation process,presenting a characteristic that can be described as ＂coexistence of multiple sources and continuity of multiple gas generating phases＂.An index system for tracing is established in accordance with such effects as the parent material inheritance,isotopic fractionation and accumulation.It is based on stable isotopic components and important tracing means such as composition,biomarker,light hydrocarbon,non-hydrocarbon gases as well as rare gas isotopes and trace elements,and can be used to trace the process of transformation of different sources and hydrocarbon generation.The ternary tracing system of gas generation and accumulation is further improved.This paper presents a gas source rock timing model,gas-source correlation method,identification index of gas origin and their tracing,as well as a preliminary model for source identification and quantification of mixed gas.