Hydrotest, gas composition, injection fluid, mass spectrometer, and U-tube gas sample analysis data gathered during SECARB project at Cranfield oil site in Mississippi. Geochemical data collected as part of geologic characterization phase of SECARB. Associated Publications: Lu, J., Cook, P. J., Hosseini, S. A., Yang, C., Romanak, K. D., Zhang, T., Freifeld, B. M., Smyth, R. C., Zeng, H., and Hovorka, S. D., 2012, Complex fluid flow revealed by monitoring CO2 injection in a fluvial formation: Journal of Geophysical Research, v. 117, B03208, doi:10.1029/2011JB008939. Lu, J., Kharaka, Y. K., Thordsen, J. J., Horita, J., Karamalidis, A., Griffith, C., Hakala, J. A., Ambats, G., Cole, D. R., Phelps, T. J., Manning, M. A., Cook, P. J., and Hovorka, S. D., 2012, CO2‒rock‒brine interactions in Lower Tuscaloosa Formation at Cranfield CO2 sequestration site, Mississippi, U.S.A.: Chemical Geology, v. 291, p. 269‒277. Yang, C., Hovorka, S. D., Treviño, R. H., and Delgado-Alonso, J., 2015, Integrated framework for assessing impacts of CO2 leakage on groundwater quality and monitoring-network efficiency: case study at a CO2 enhanced oil recovery site: Environmental Science &Technology, v. 49, p. 8887–8898, doi:10.1021/acs.est.5b01574.