Geochemistry of carbonate cements in Cretaceous sandstones, southeast Benue Trough, Nigeria: Implications for geochemical evolution of formation waters

The low δ18O value of some calcite cements (−11.62‰, −12.66‰, −14.31‰ PDB) suggests that an influx of meteoric water may have occurred in the Turonian-Coniacian, although the low value could also result from an abnormal geothermal gradient associated with tectonic activity in the trough. The elemental and isotopic composition of these cements varies as a function of the time of precipitation.