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GEOPHYSICAL PURSUIT, INC.1740 Westheimer

Suite 200Houston, TX 77098

(713) 529-3000

2895 Highway 190Suite 227

Mandeville, LA 70471(985) 727-6720

Niobrara Phases 1 & 2 Weld County Colorado 985.76 mi2

Acquisition and Processing by:

Published: 19 November 2015

Geoph

ysical Pu

rsuit 3

-D S

urveys

GEOPHYSICAL PURSUIT, INC.1740 Westheimer

Suite 200Houston, TX 77098

(713) 529-3000

2895 Highway 190Suite 227

Mandeville, LA 70471(985) 727-6720

Niobrara Phases 1 & 2 Weld County Colorado 985.76 mi2

Acquisition and Processing by:

Acquisition Parameters Phase 1 & 2 (bright yellow) Phase 1 Ext. (green) Recording Template: 16 E-W receiver lines of 140 groups 16 E-W receiver lines of 140 groups NNW-SSE source lines with 14° slant NNW-SSE source lines with 14° slant Receiver Geometry: 1,155ft @ 165ft (146.5/mi2) 1,155ft @ 165ft (146.5/mi2) Source Geometry: 1,155ft @ 165ft (146.5/mi2) 825ft @ 165ft (204.8/mi2) Energy Source Type: Vibroseis; 3 x 60,000lb Vibroseis; 3 x 60,000lb Energy Source Details: Four 6-96Hz sweeps of 12sec Two 6-96Hz sweeps of 16sec Recording Instruments: Sercel 428 Sercel 428 Nominal Far Offset: 14,821ft 14,821ft Nominal Fold: 80 112 Acquisition Bin Size: 82.5ft x 82.5ft 82.5 x 82.5ft Record Length: 5 seconds @ 2ms 5 seconds @ 2ms Acquisition Period: Jan 2011- Jan 2012 Jul-Nov 2011 Contractor: Geokinetics 309 Geokinetics 309

Processing Sequence (archive datasets in bold) by Geokinetics April 2012

1. Reformat & merge geometry 2. Trace Edit 3. Spherical Divergence Correction / Gain Recovery 4. Noise Suppression/Removal 5. Surface Consistent Amplitude Compensation 6. Preliminary Velocity Analysis @ 1mi interval 7. Refraction Statics Correction 8. Surface Consistent Deconvolution 9. Velocity Analysis Update @ 1mi interval 10. Residual Statics Correction 11. Data Regularization 12. Kirchhoff PreStack Time Migration (PrSTM) ½mi velocity lines 13. Velocity Analysis for smoothed migration velocities @ ½mi 14. PrSTM ½mi velocity lines for QC 15. Full Volume curved-ray 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 (Enhanced)

Products:

A. Full offset PrSTM stack volume (SEG-Y) a. Raw b. Enhanced

B. Partial angle PrSTM stack volumes (SEG-Y); Near (5-17°), Mid (15-27°) & Fars (25-37°) C. PrSTM CMP gathers (SEG-Y)

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

D. Velocity fields a. Migration RMS smoothed (SEG-Y) b. Stacking RMS (ASCII)

E. Field shots w/ geometry (SEG-Y)

Published: 19 November 2015

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

Acquisition by:

Published: 1 June 2016

Geoph

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

Acquisition by:

Published: 1 June 2016

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