seg post-convention workshop seam phase 1: initial results technical and operational overview of the...
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SEG Post-Convention WorkshopSEAM Phase 1: Initial results
Technical and Operational Overview of the SEAM Phase I Project
Michael Fehler
SEAM Mission
Advance the science and technology of applied geophysics through a cooperative industry
effort focused on subsurface model construction and generation of synthetic data
sets for geophysical problems of importance to the resource extraction industry.
What Do We want to Accomplish?
• State-of-the-art geophysical numerical modeling
• Develop datasets for testing geophysical imaging and characterization techniques
• First model is Deepwater Gulf of Mexico– Subsalt
– Variable-density acoustic and other geophysical datasets
• SEAM Phase I (This talk)
• SEAM RPSEA (Talk at 3:15)
SEAM Operation
• Board of Directors (BOD)– Bill Abriel, Chair
– Broad overview focused on future of SEAM and SEAM/SEG relationship
• Management Committee (MC)– Kevin Bishop, Chair
– Each participating company has one vote
– Make project-specific decisions
• Steve Danbom is liaison between BOD and MC
SEAM Technical Organization
• 6 Technical Committees composed of members from participating companies– Define and implement objectives and work plans– Program Manager coordinates work by and among
committees
• Communication through regular meetings and e-community– Technical committee co-chairs meet ~monthly– Management Committee meets quarterly
• One member from each participating company• Decision making body
SEAM Technical Committees and Co-Chairs
• Model Design Committee – Joe Stefani and Richard Day
• Numerical Design Committee – Scott Morton and John Anderson with help from Bill Symes
• Acquisition Design Committee– Chuck Meeder and Adam Seitchik
• NonSeismic– Michael Frenkel and Neville Barker
• Execution Committee– Peter Wang and Dan Ebrom
• Data Storage and Distribution Committee– Stew Levin
SEAM Vendors• Numerical Simulations done by Tierra Geophysical
– Careful evaluation prior to selection by Vendor Qualification Process
• Quality Control done on simulations by Nexus Geosciences Inc.– QC procedure to evaluate quality and reliability of data
delivered by Tierra Geophysical– Regularly communicate and report to Project Manager
• Data Storage & Distribution done by Landmark Graphics– Data are stored in compressed format (10:1 compression)– Delivery of either compressed or uncompressed data– Will store model files, all model description files, simulation
data, classic datasets
Model Parameters
• Dimensions– 35 km East-West
– 40 km North-South
– 15 km deep
• Gridded model on 10 m grid– 84 GB per parameter
• Velocity Range– 1490 km/s (water) to 4800 m/s (Cretaceous)
• Density Range 1.003 gm/cc to 2.904 gm/cc
Acquisition Parameters (Phase 1 Seismic)
• Variable-density acoustic• Frequency: <1 to >25 Hz• Source-receiver separation: max 9.9 km
– Receivers in rectangular grid around source
• Shot locations: 150 m grid over entire model• Shot, receiver depths: 15 m• Receiver spacing: 30 m• Sample interval 8 ms• Trace length: 16 s• Calculation grid: 30 km (for aperture)• 60K+ shots, 450K traces/shot• 3.5 GB data volume per shot (> 200 TB total)
Source and receiver depths are 15 meters.Npoles=8 f3db=26 Npoles=2 f3db=20Npoles=6 f3db=24 Npoles=1 f3db=5Npoles=4 f3db=22
Source wavelet Two ghosts 30 Hz high cut
SEAM Source Wavelet
Broad bandFlat spectrum after surface ghostsCausal
Source: C. Stork, Tierra Geophysical
Source: C. Stork, Tierra Geophysical
Status of Simulations, Phase IVariable-Density Acoustic
Number of Shots
Velocity at 4 km depth
40
30
20
10
0
Nor
th
Velocity at 4 km depth
40
30
20
10
0
Nor
th
Velocity at 4 km depth
40
30
20
10
0
Nor
th
Dark Blue: in StoragePurple: QC CompleteDark Red: Simulated
40
30
20
10
0
Nor
th
7599 Shots deliveredto participants
(about 3 TB compressed)
Blue: 2793-shot Classic DatasetRed: 9-line Classic Datasets – 15 and 17 m receiver depths – free and absorbing upper surface
40
30
20
10
0
Nor
th
Next 6 Talks about SEAM Development and Results
• Model Design and Construction
• Numerical Simulation Issues
• Acquisition Design and Classic Datasets
• Data Storage & Distribution including compression
• CSEM modeling
• Gravity modeling
Discussion of Phase II Project
• Begins at 4:00
• Two major options presented– 4D
– Land
• Your input and preference are solicited