Calibration of Seismic Attributes for Reservoir Characterization ...

Figure 23: The combined seismic facies using multiple traces. ................................................... 31Figure 24: Conventional thin-bed tuning model with notations for our data set. ......................... 33Figure 25: Modeled seismic response........................................................................................... 34Figure 26: Seismic features through the main delta system.......................................................... 34Figure 27: RMS Amplitude plotted against summed thickness of sandstone and limestone. ...... 35Figure 28: Inverted impedance curves using the GRNN model at 36 wells................................. 37Figure 29: Crosslines 171 (a) and 125 (b) of the inverted impedance data .................................. 38Figure 30: Inverted impedance volume (GRNN model) with different opacity cut-offs. ............ 38Figure 31: Inverted impedance data using the PNN model. ......................................................... 39Figure 32: Crossline 117 of the invertedimpedance volume using the PNN model..................... 40Figure 33: Actual sandstone and limestone thickness plotted against predicted .......................... 40Figure 34: Estimated sandstone thickness of Caddo main delta system (PNN model) ................ 40Figure 35: Traverse line showing the inverted impedance using CSSI model ............................. 41Figure 36: Inverted impedance volume using the CSSI with different opacity cut-offs. ............. 42Figure 37: 3D perspective view of the sand structure................................................................... 44Figure 38: Smoothed production history of the 4500-ft reservoir ................................................ 44Figure 39: Inverted (legacy data) volume showing acoustic impedance ...................................... 45Figure 40: Time-lapse difference mapped on the 4500-ft horizon .............................................. 45Figure 41: Changes in P-wave velocity (Vp), Poisson’s ratio (PR............................................... 46Figure 42: Predictions for Amplitude-versus-Offset effect. ......................................................... 46Figure 43: Amplitudes extracted from the partial-offset data for the 4500-ft reservoir ............... 47Figure 44: Amplitudes extracted from the partial-offset data over the Little Neighbor. .............. 47Figure 45: A traverse through the inverted acoustic impedance volume...................................... 48Figure 46: Cartoon schematic ....................................................................................................... 49Figure 48: (Approximate) location of the seismic survey............................................................. 51Annual Technical Progress Report Michigan Technological University DE-AC26-98BC15135October, 2001 Page 7