Exploration and analysis of oil and gas field ( 3D seismic survey)

Post on 16-Apr-2017

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Exploration & Production Life Cycle

• Exploration• Appraisal • Development• Production• Decommissioning

Petroleum System

Seismic Survey

Performance rate• Survey location • Time of year • Survey size, particularly sail line length• Vessel configuration • Line orientation and prevailing current direction • Fishing and shipping activity in the survey area • Other seismic operations • Marine mammal activity • Drilling and subsea equipment maintenance

Types of Seismic Survey

• 2-D Seismic Survey• 3-D Seismic Survey• 4-D Seismic Survey

2-D Seismic Survey

2- D Seismic Interpretation

Advantages of 2-D Seismic Survey• Easiest survey method• Inexpensive

Disadvantages of 2-D Seismic Survey

• Not effective in some location• Anomalies are harder to map,• Not of better quality • Exploration drilling success rate using 2D seismic data is very less (25%)

3-D Seismic Survey

Acquisition of a typical 3D marine seismic survey

Effect of Azimuth Angle

Comparison between images acquired with narrow-azimuth and wide-azimuth methods

Towing-Depth Trade-Offs

Ghost multiples, or reflections at the underside of the sea surface

4-D Seismic Survey

3-D Time 4-D

Benefits of 4-D seismic Survey

The flow of the hydrocarbons within can be

traced and better

understood

Helps geologists to understand

how the reservoir

reacts to gas injection or

water flooding

Help to locate untapped

pockets of oil or gas within the reservoir

Comparison Between 2-D and 3-D

1. Survey Line

2-D and 3-D seismic Survey Line

2. Image Quality

Analogical comparison of quality of image in 2-D and 3-D

3. Economic Analysis

Comparisons of 2D and 3D activities in Western Canada for the year of 1997