Diagenesis of Sandstones and Limestones in the Foreland Shelf of Kansas

点击翻译按钮获取中文摘要

Entry of heated brines into foreland shelf sediments of the US Midcontinent accompanied the Ouachita orogeny during the Pennsylvanian and Permian. The water brought heat and possibly other constituents at the same time to promote diagenesis in foreland areas and contributed to formation of oil and mineral deposits. A diagenetic scenario involving lateral motion of hot water at shallow depths differs from most models. This research will attempt to establish the importance of this regional heating for Middle and Late Pennsylvanian sandstones and limestones in southeastern Kansas. Earlier work has shown that limestones and sandstones there acted separately during late diagenesis, forming baroque dolomite-like cements from constituents derived from different sources. The proposed research will develop a diagenetic model for a small pilot area. The model will assess the importance of regional events and local controls in diagenesis of the area and will integrate diagenesis and sandstones and limestones. Research will include optical, cathodoluminescence, and back- scattered electron microscopy to investigate relations of diagenetic phases and stratigraphy of the cements. Fluid inclusion, isotope, and trace-element data will establish conditions of diagenesis and sources of constituents.