论沉积盆地内成岩相系划分及类型

Classification and types of diagenetic lithofacies systems in the sedimentary basin

沉积盆地内成岩作用和成岩相系划分研究,不仅有助于提升对沉积盆地内金属矿产、非金属矿产、能源矿产(石油、天然气、煤和铀矿)等同盆共存富集与协同成岩成矿成藏作用等方面的研究水平,也有助于提升对沉积盆地形成演化历史、盆山和盆山原耦合转换等大陆动力学过程的深入研究。将沉积盆地内成岩作用和成岩相系划分与地球化学岩相学识别技术紧密结合,采用构造岩相学与地球化学岩相学研究思路和方法,以成岩事件序列为主线,将沉积盆地内成岩相系划分为:①成盆期埋深压实物理-化学成岩作用和成岩相系;②盆地改造期构造-热事件成岩作用与构造热事件改造成岩相系;③盆内岩浆叠加期构造-岩浆-热事件成岩作用和岩浆叠加成岩相系;④盆地表生变化期表生成岩作用和表生成岩相系。从地球化学岩相学成岩机理上,对成岩相系的成岩环境和成岩机理进行识别,促进非金属矿产、金属矿产-油气资源-煤-铀等同盆共存与协同富集成矿成藏机理研究和深部矿产资源预测。

Classification of diagenesis lithofacies systems in sedimentary basin may help promote the research level of enrichment and synergistic diagenesis-mineralization for metallic and nonmetallic deposits and such energy mineral resources as oil,gas,coal and uranium deposits in the same basin;moreover,it may encourage researchers to get a better understanding of geodynamic process in basin evolution and formation,coupling transitions of basin-mountain,and coupling transitions of basin-mountain-plateau.In this study,systems of diagenetic lithofacies in the basin were categorized based on the principal line of diagenesis events in the basin,using means of tectonic lithofacies and geochemical lithofacies,and combining diagenesis and systems of diagenetic lithofacies with recognition technology of geochemical lithofacies.Systems of diagenetic lithofacies in the basin were classified into four systems,i.e.,diagenesis system formed by buried compaction to chemical diagenesis at the stage of basin formation,renovated diagenesis system formed by tectonic-thermal events at the stage of basin renovation,magmatic superimposed diagenesis system formed by thermal events of tectonics-magmatism at the stage of magmatic intrusions in the basin,and supergene diagenesis system at the stage of supergene modification in the basin.Therefore,environments of diagenetic lithofacies and diagenetic mechanisms may be recognized from the mechanism of geochemical lithofacies.This may help promote the research level of enrichment and synergistic diagenesis-mineralization for metallic and nonmetallic deposits,such energy mineral resources as oil,gas,coal and uranium deposits and predication of deep mineral systems in the same basin.