This study, considering original detrital compositions and diagenetic alterations, relates sandstone and shale mineral and chemical composition to provenance and mass balance between the sedimentary assemblage and its provenance. Mature quartz-rich sandstones and siltstones with clay-rich shales in cores at depths of 60 m–5.2 km and burial temperatures of <50 to >150 °C from over 50 wells were utilized in this work. These provide the material for analysis of compositions and alterations in coastal and shallow marine clastic sedimentary rocks of the Middle Ordovician Simpson Group in Oklahoma and Kansas, U.S.A. Mineral and geochemical data were obtained by optical petrography, X-ray diffraction, scanning electron microscopy, electron microprobe, and whole rock X-ray fluorescence and ICP/MS analyses. Results of the study show significant progressive diagenetic changes with increased burial depth and temperature. Mineralogically and chemically, less altered rocks are comparable to modern quartz-rich sands and kaolinitic muds in siliciclastic sediments developed during humid tropical weathering in crystalline basement shield provenance in Africa and South America. By analogy to modern tropical cases, muds composed of major kaolinite with minor smectite and illite at deposition, were diagenetically transformed to illite-rich rocks by possible microbial action, at surface to shallow (<200 m, <40 °C) burial with influx of K, Rb and Mg from seawater. In sandstones, early open system diagenesis with calcite cementation and quartz overgrowths occurred at <1 km depth and < 40 °C. Further closed system silica diagenesis and K-metasomatism, occurred with deeper burial (to 3+ km and 100 °C) in the Pennsylvanian and Permian and later, during and following uplift of the Arbuckle and Wichita Mountains, with establishment of a new fold and thrust belt structural and hydrologic regime. Pressure solution of quartz and the illite to muscovite transformation in shales in the depth range 3–8 km, yielded silica for later generation quartz cement (10- >20%) in sandstone buried >3 km. During deep burial, high temperature (>110 °C) calcite cement from deep basin sources was precipitated in sandstones. Geochemical mass balance estimates, physical, and chemical evidence suggest quartz cement was sourced from within clastic rocks of the Simpson Group with minor external contribution of SiO2. Na is in low abundance due to loss in solution during weathering in the provenance. Rare earth elements (REE) have typical abundances and distributions in shales with enrichment in light REE; littoral environment siltstones and matrix-rich sandstones display enrichment of heavy REE in phosphatic brachiopod shell fragments.