time (myr)

Time (myr)Time (myr)-90 my -65 my

~present

Seismic Direct Dinosaur Indicator (DDI)?Seismic Direct Dinosaur Indicator (DDI)?

Imaging Dinosaur Imaging Dinosaur Fossils by Seismic Fossils by Seismic

Tomography and GPRTomography and GPRTravis Crosby, Min Zhou, Dave Sheley, Travis Crosby, Min Zhou, Dave Sheley, Scott Scott

SampsonSampson, Paul Gettings and GT Schuster (U Utah), Paul Gettings and GT Schuster (U Utah)Craig Lipus (Geometrics)Craig Lipus (Geometrics)

OutlineOutline1.1. Motivation & ObjectiveMotivation & Objective

2.2. S. Utah Hadrosaur Site S. Utah Hadrosaur Site

3.3. Seismic Tomography & GPR Seismic Tomography & GPR ExperimentsExperiments

4.4. Results & ProblemsResults & Problems

ProblemProblem: Where are dinosaurs?Where are dinosaurs?

Dinosaur Fossil DetectionDinosaur Fossil Detection

Paleontologists dig rocks!Paleontologists dig rocks!

SolutionSolution: Seismic/GPR DDI?Seismic/GPR DDI?

Site Location MapSite Location Map

ViewView

Seismic and GPR Survey AreasSeismic and GPR Survey Areas

Hadrosaur QuarryHadrosaur Quarry

Site PhotographsSite Photographs

8 m8 m

0.5

m0.

5 m

24 g

eo/li

ne24

geo

/line 12 m12 m

GPR SurveyGPR Survey

8 m8 m

0.5

m0.

5 m

24 g

eo/li

ne24

geo

/line 12 m12 m

3-D Velocity Tomogram3-D Velocity Tomogram

Comparison with Adjacent Comparison with Adjacent TrenchTrench

11.2 ft11.2 ft

Shot Gather (400 Hz)Shot Gather (400 Hz)0 ms0 ms

60 ms60 ms

>80K Traveltime Picks>80K Traveltime Picks3D Traveltime Tomography3D Traveltime Tomography1-2 m Wavelength1-2 m Wavelength

Residual vs Iter. #Residual vs Iter. #1.8 ms1.8 ms

1.6 ms1.6 ms11 2020Iteration #Iteration #

RM

S R

esid

ual

RM

S R

esid

ual

0 m0 m

3 m3 m

0 m0 m

3m3m

0 m0 m

3 m3 m

N-S Vertical Section TomogramsN-S Vertical Section Tomograms

0 m 12 m0 m 12 m

1.5 km/s1.5 km/s

0 km/s0 km/s

1.5 km/s1.5 km/s

0 km/s0 km/s

1.5 km/s1.5 km/s

0 km/s0 km/s

Preliminary ResultsPreliminary Results

0.00 1.25 2.50 3.75 5.00 6.25 7.50

0

2

4

6

8

10

Position in metres

Dept

h in

met

res

LINE 7.5 Depth Section

0.00 1.25 2.50 3.75 5.00 6.25 7.50

-2

0

2

4

6

8

Position in metres

Dept

h in

met

res

LINE8.5 Depth Section

Radar Data

Potential ProblemsPotential Problems1.1.Data Quality ControlData Quality Control

1.1.AnisotropyAnisotropy

1.1.AttenuationAttenuation

Geophone #Geophone #

SHO

T #

SHO

T #

Data QC:Data QC: EditEdit

Data QC: ReciprocityData QC: Reciprocity

Attenuation?Attenuation?0 ms0 ms

25 ms25 ms

-2000-2000 20002000-2000 m/s-2000 m/s -2000 m/s-2000 m/s

-1500-1500

150015001500 m/s1500 m/s

-1500 m/s-1500 m/s-2000 m/s 2000 m/s-2000 m/s 2000 m/s

AnisotropyAnisotropy??

Dx=0-2 mDx=0-2 m

Dx=2-6 mDx=2-6 m

Dx=0-12 mDx=0-12 m

0 m0 m

8 m8 m

0 m0 m

8 m8 m

0 m0 m

8 m8 m

Depth Slice TomogramsDepth Slice TomogramsZ=1 m

Z=2 m

Z=3 m

0 m 12 m0 m 12 m

1.5 km/s1.5 km/s

0 km/s0 km/s

1.5 km/s1.5 km/s

0 km/s0 km/s

1.5 km/s1.5 km/s

0 km/s0 km/s

ConclusionsConclusions

• Seismic Tomography not DDISeismic Tomography not DDI

• Seismic Tomography IDDISeismic Tomography IDDI

• GPR PreliminaryGPR Preliminary• Near-Surface Problems:Near-Surface Problems: Attenuation, Anisotropy, QCAttenuation, Anisotropy, QC Is a hadrosaur fossil low or Hi velocity?Is a hadrosaur fossil low or Hi velocity?

Differential GPS: cm AccuracyDifferential GPS: cm Accuracy

time (myr)

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