1. Generation of 2D Wave Equation Synthetics Across Nissen-defined Cross- Sections of Dickman Field Rachel Barber, Susan E. Nissen, Kurt Marfurt Dickman Field is located on the western flank of the Central Kansas uplift, a northwest-trending anticline that was uplifted and eroded in post-Mississippian to pre- Desmoinesian time (Merriam, 1963), forming a pronounced regional unconformity surface. In Dickman Field, Desmoinesian Pennsylvanian strata unconformably overlie Mississippian reservoir rocks of the Meramecian Spergen and Warsaw Limestones. Karst development in Mississippian rocks beneath the pre- Pennsylvanian unconformity surface has been reported throughout western Kansas, including Ness County (e.g., Goebel, 1966; Nodine-Zeller, 1981; Montgomery et al., 2000). A solution-enhancement of natural fractures (rather than cavern formation) by karst processes is believed to influence oil and water production in these Mississippian reservoirs (Montgomery et al., 2000). The velocities were generated using the sonic log from the Dickman 6 well; centrally located in the area of study. A sequestration inspired project in Central Kansas has inspired further geophysical research for karst topography identification in seismic. There is an openly fractured unconformity in between the Mississippian reservoirs and Pennsylvanian formation, which is where the karsting is taking place. The Western Interior Plains aquifer system flows underneath depleated Mississippian reservoirs providing the fluid flow. The sequestration is driven by environmental concerns as well as enhanced oil recovery. The purpose of this research is to better identify karst in seismic data though making synthetics using wave modeling. Acoustic wave propagation through Karst model. (Tesseral 2D) Work Flow:  Use sonic log to determine velocities  Generate Model  Set acquisition parameters  Prepare model processing  Run Acoustic model  Merge grid for shot gathers  Merge grid for snap  Normalize  Run Kirchoff migration Model 1: Karst Model 2: Filled-Karst Susan Nissen, Timothy Carr, Kurt Marfurt, Charlotte Sullivan.Using 3-D seismic volumetric curvature attributes to identify fracture trends in a depleted Misssiisppian carbonate reservoir: Implications for assessing candidates for CO2 sequestration.Kansas Geological Survey.University of Kansas. Allied Geophysical Laboratories, UH. Pacific Northwest National Laboratories. Abstract image courtesy of http://www.kgs.ku.edu/PRS/publication /2004-56/reflector.html Intro images and general karst model courtesy of Sue Nissen. Tesseral 2D used to generate all models shown. Special thanks to Roderick Perez for all your help. Works Cited Sand, silt, and shale -12,000 ft/s Top Miss Gilmore City Limestone - 19,000 ft/s Cherty dolomite -15,000 ft/s Av vel from surface approx. 10,900 ft/s Base Penn Lime * All fractures are 10 ft wide 150 ft 30 ft General Karst model Base Penn Lime Top Cherokee Sand Top Conglome rate (Karst Fill) Top Mississipi an Top Gilmore City Ave.: 85.18 Ave.: 88.72 Ave.: 93.21 Ave.: 70.01 Ave.: 85.18 Sonic (ms/ft) Depth (ft) Synthetic seismogram Synthetic seismogram with Kirchoff migration