Petrology, Porosity Evolution, and Geochemistry of Upper Cambrian and Lower Ordovician Strata in Southern Missouri

密苏里州南部的上寒武统和下奥陶统碳酸盐岩是该地区主要的密西西比河谷型(MVT)矿藏的所在地。此外，它们是该地区的主要淡水含水层。这项研究将研究：1)岩石学(包括孔隙度和渗透率)和2)这些单元的地球化学。这些信息将被用来解释该地区的成岩历史，特别是关于导致MVT矿床的区域盆地流体迁移。这项研究还将评估与区域矿化有关的晚期成岩胶结物的体积，并在区域矿化开始之前和密苏里州南部矿化期间的不同阶段估计孔隙度和渗透率。这些信息将有助于模拟晚古生代成矿作用期间中大陆的盆地流体流动，更好地了解现今含水层，并将为了解盆地流体对台地碳酸盐的晚期成岩蚀变作用提供有益的案例研究。

Upper Cambrian and Lower Ordovician carbonate rocks of southern Missouri host the major Mississippi Valley-type (MVT) mineral deposits of the region. Additionally, they are the principal fresh water aquifers for the area. This study will investigate: 1) petrology (including porosity and permeability) and 2) geochemistry of these units. This information will be used to interpret the diagenetic history of the region, particularly with regard to regional basin fluid migration that resulted in MVT ore deposits. The study will also evaluate the volume of late diagenetic cements, related to regional mineralization, and estimate porosities and permeabilities prior to the onset of regional mineralization and at various stages during mineralization in southern Missouri. This information will be valuable for modeling basinal fluid flow on the midcontinent during late Paleozoic mineralization, gaining a better understanding of the present day aquifers, and will serve as a useful case study for the understanding of late diagenetic alteration of platform carbonates by basinal fluids.