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present. -65 my. Seismic Direct Dinosaur Indicator (DDI)?. ~. -90 my. Time (myr). Imaging Dinosaur Fossils by Seismic Tomography and GPR. Travis Crosby, Min Zhou, Dave Sheley, Scott Sampson , Paul Gettings and GT Schuster (U Utah) Craig Lipus (Geometrics). Outline.
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present -65 my Seismic Direct Dinosaur Indicator (DDI)? ~ -90 my Time (myr)
Imaging Dinosaur Fossils by Seismic Tomography and GPR Travis Crosby, Min Zhou, Dave Sheley, Scott Sampson, Paul Gettings and GT Schuster (U Utah) Craig Lipus (Geometrics)
Outline • Motivation & Objective • S. Utah Hadrosaur Site • Seismic Tomography & GPR Experiments • Results & Problems
Solution: Seismic/GPR DDI? Dinosaur Fossil Detection Problem: Where are dinosaurs? Paleontologists dig rocks!
Outline • Motivation & Objective • S. Utah Hadrosaur Site • Seismic Tomography & GPR Experiments • Results & Problems
Outline • Motivation & Objective • S. Utah Hadrosaur Site • Seismic Tomography & GPR Experiments • Results & Problems
0.5 m 12 m 24 geo/line 8 m Site Photographs
0.5 m 12 m 24 geo/line 8 m GPR Survey
Outline • Motivation & Objective • S. Utah Hadrosaur Site • Seismic Tomography & GPR Experiments • Results & Problems
11.2 ft Comparison with Adjacent Trench
Shot Gather (400 Hz) 0 ms >80K Traveltime Picks 3D Traveltime Tomography 1-2 m Wavelength 60 ms
Residual vs Iter. # 1.8 ms RMS Residual 1.6 ms 1 20 Iteration #
N-S Vertical Section Tomograms 1.5 km/s 0 km/s 0 m 3 m 0 m 3m 1.5 km/s 0 km/s 0 m 3 m 1.5 km/s 0 km/s 0 m 12 m
Radar Data Preliminary Results
Outline • Motivation & Objective • S. Utah Hadrosaur Site • Seismic Tomography & GPR Experiments • Results & Problems
Potential Problems Data Quality Control Anisotropy Attenuation
Data QC:Edit SHOT # Geophone #
Attenuation? 0 ms 25 ms
1500 m/s 1500 -1500 -1500 m/s -2000 m/s 2000 m/s Anisotropy? Dx=0-2 m Dx=2-6 m Dx=0-12 m -2000 -2000 m/s 2000 -2000 m/s
Depth Slice Tomograms 1.5 km/s 0 km/s 0 m 8 m Z=1 m 0 m 8 m 1.5 km/s 0 km/s Z=2 m 0 m 8 m 1.5 km/s 0 km/s Z=3 m 0 m 12 m
Conclusions • Seismic Tomography not DDI • Seismic Tomography IDDI • GPR Preliminary • Near-Surface Problems: • Attenuation, Anisotropy, QC • Is a hadrosaur fossil low or Hi velocity?