PHASE 45 LEVIATHAN Pre-Stack Kirchhoff Depth Migration

MULTI-CLIENT 2D SURVEY

ACQUISITION PARAMETERS

Acquisition Date: September 17, 1996 - September 19, 1998 Data Acquired By: Geco-Prakla

Mileage: 61,679 miles Shooting Orientation: Northeast/Southwest

Recording Instrument: DFS V / Nessie 3 / Nessie 4 Streamer Type: Geco-Prakla Transformerless GX600

Streamer Positioning: RGPS / Compasses Airgun Source: 7918 cubic inches

Gun Depth: 7.5 meters Shotpoint Interval: 37.5 meters

Group Interval: 25 meters Recording Channels: 240 / 320

Streamer Depth: 9 meters (+/-1.5 meters) Streamer Length: 6000/8000 meters

Record Length: 13/14 seconds Sample Interval: 4 milliseconds

Nominal Fold: 80/106

PROCESSING SEQUENCE Data processing performed by: Spectrum Energy & Information Technology Processing Completed August 2004

PSDM PROCESSING

Read radon CDP gather tapes from Phase 45 AGAIN Processing Input sediment only velocity file Depth migrate Interpret top of salt Salt flood the velocity model Depth migrate Interpret base of salt Output interval velocity field Final Kirchhoff prestack depth migration (Depth step of 5 meters) Apply residual velocity correction- output CDP gather tape Stack- output raw migration tape Filter and scale – output processed migration tape Convert back to time – output tape

AVAILABLE PSDM DELIVERABLES

Read radon CDP gather tapes from Phase 45 AGAIN reprocessing Pre stack depth migrated- processed (in depth – m or ft) Pre stack depth migrated-processed (converted back to time) Pre-stack depth migrated CRP gathers with residual NMO Final migration velocity volume (in depth – m or ft) Sediment interval velocity field (in depth –m of ft) Interpreted top of salt horizon (ASCII – m or ft) Interpreted base of salt horizon (ASCII – m or ft) Interpreted water bottom horizon (ASCII – m or ft) Post stack navigation – UKOOA

8 June 2015

TEXAS LOUISIANA

MISSISSIPPI ALABAMA

FLORIDA

Lund Walker Ridge

East Breaks

Atwater Valley Green Canyon

Garden Banks

Keathley Canyon

Alaminos Canyon

Mississippi Canyon

Galveston

High Island

Vermilion

Port Isabel

Lund South

Ship Shoal

Amery Terrace

Brazos Area

Mobile

Eugene Island

West Cameron

Main Pass

High Island South Addition

West Cameron South Addition

Viosca Knoll

South Timbalier

Sigsbee Escarpment

High Island E. Add, S. Ext

Mustang Island East Addition

Matagorda Island Galveston

South Addition

Main Pass S. & E. Addition

West Delta

Corpus Christi

Ewing Bank

Ship Shoal South AdditionEugene Island

South Addition

Brazos South Addition

South Timbalier South Addition

East Cameron

Lloyd Ridge

West Cameron West Addition

De Soto Canyon

Henderson

Vermilion South Addition

Destin Dome

East Cameron South Addition

High Island East Addition

Grand Isle

South Padre Island East Addition

South Marsh Island South Addition

North Padre Island East Addition

South Pass

Breton Sound

South Marsh Island North Addition

South Marsh Island

Pensacola

Chandeleur

West Delta South Addition

Florida Plain

Grand Isle South Addition

South Pelto

South Pass S.& E. Addition

Sabine Pass

Chandeleur East Addition

Bay Marchand

88°W

88°W

92°W

92°W

96°W

96°W32

°N 32°N

28°N 28

°N

24°N 24

°N

PHASE 45 LEVIATHANMULTI-CLIENT 2D SEISMIC SURVEY

0 30 60 90 12015

MilesN:\Public\GIS\Arc Map Documents\GoM\SpecSheetMaps\2D\Phase 45 Leviathan Spec Sheet (Port).mxd

June 04, 2015