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Niobrara Phase 5Larimer & Weld Counties, Colorado

220.50 mi2

Published: 12 April 2018

Geoph

ysic

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ursu

it 3-D

Su

rveys

Niobrara Phase 5Larimer & Weld Counties, Colorado

220.50 mi2

Acquisition ParametersRecording Template: 20 N-S receiver lines of 96 groups

NE-SW source lines with 45° slant

Receiver Geometry: 220ft @ 1,100ft lines (115.2/mi²)

Source Geometry: 220ft @ 1,320ft lines (96.0/mi²)

Energy Source Type: Vibroseis; 3 x 60,000lb

Energy Source Details: Four 6-96Hz sweeps of 12sec

Recording Instruments: IO RSR

Nominal Far Offset: 14,779ft

Nominal Fold: 80

Acquisition Bin Size: 110ft x 110ft

Record Length: 5 seconds @ 2ms

Acquisition Period: Q4 2013 – Q1 2014

Contractor: Geokinetics

Processing Sequence (archive datasets in bold)

1. Reformat & merge geometry2. Trace Edit3. Spherical Divergence Correction / Gain Recovery4. Noise Suppression/Removal5. Surface Consistent Amplitude Compensation6. Preliminary Velocity Analysis @ 1mi interval7. Refraction Statics Correction8. Surface Consistent Deconvolution9. Velocity Analysis Update @ 1mi interval10. Residual Statics Correction11. Data Regularization12. Kirchhoff PreStack Time Migration (K PrSTM) ½mi grid for velocity analysis13. Velocity Analysis for smoothed migration velocities14. Kirchhoff PreStack Time Migration ½mi velocity lines for QC15. Full Volume curved-ray K PrSTM (Raw PrSTM gathers unflattened)16. Final Stacking Velocity Analysis (½mi interval)17. Post migration conditioning (NMO corrected PrSTM gathers)18. Angle stacks (near, mid & far)19. Stack (Raw)20. Post stack conditioning (Conditioned)

Products:

A. Full offset 3D KPrSTM stack volume (SEG-Y)a. Rawb. Enhanced

B. Partial angle stack volumes (SEG-Y); Near, Mid & FarC. KPrSTM gathers (SEG-Y)

a. Raw w/ migration velocities removed (unflattened)b. NMO corrected, conditioned w/o mute

D. Velocity fieldsa. Migration (RMS SEG-Y)b. Stacking (RMS ASCII)

Published: 12 April 2018

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Surveys

Niobrara Ph1-5 2014 MergeWeld, Morgan & Larimer Counties, Colorado1,382.90 mi2

Published: 12 April 2018

Geoph

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Surveys

Niobrara Ph1-5 2014 MergeWeld, Morgan & Larimer Counties, Colorado1,382.90 mi2

Published: 12 April 2018

Acquisition ParametersInput Surveys: Niobrara Phase 1 788.68 sq mi

Niobrara Phase 2 197.08 sq miNiobrara Phase 3 333.03 sq miNiobrara Phase 4 39.14 sq miNiobrara Phase 5 220.50 sq mi

Processing Sequence by Tricon Geophysics, Inc. October 20141. Append Geometry @ 110x110ft grid2. Trace edit & spike suppression3. Refraction Statics; datum = 6,000ft, replacement velocity = 7,500ft/sec4. Noise Attenuation; shot domain5. Spherical Divergence gain recovery6. Surface Consistent Amplitude Compensation7. Surface Consistent Deconvolution8. Spectral Balancing9. Residual Statics & Velocity Analysis @ ½mi (3 passes) 10. Phase Match to Ph3 Cummins survey11. AGC; 750ms12. Residual Statics13. Flex Bin @ 110ft radius14. CMP consistent statics15. PrSTM target line Velocity Analysis; smooth for PrSTM16. TSUNAMI Kirchhoff PreStack Time Migration; 8,000ft radial aperture17. Gather flattening and final stretch 15% stretch mute18. Stack19. Trace Balancing20. 3D FXY Spatial Prediction Filtering21. Rotate phase -62°22. Filter

Products:A. Full offset PrSTM stack volume (SEG-Y)

a. Enhancedb. Enhanced +FXY