Objective
- Define the structure of the land
https://mpcl.com.pk/processing/
https://www.slb.com/products-and-services/delivering-digital-at-scale/software/omni
https://mpcl.com.pk/
# Softwares
- Schlumberger (Mega 2)
# Geo mapping (Interpretation)
The waves are synthetically (artificially generated)
- Explosive
- Vib
- Air gun
Acquisition is done using detector
- Digitized using a unit
Activity is based on the on demand survey
- Dimensions are given in 2d 3d
- Recording is for a time period
Department: Exploration
Survey
Services
- Drilling
- Seismic Activity
- MSU
- Alpha, Beta, Charlie
Real time survey points (RTA)
Drilling survey
- Explosive
Recording
-
Processing
Acoustic Incident (Density contrast)
- Reflection
- Refraction
Area of Interest
- 14 KM to 20 KM
Sonic Logging ...*
From seismic data, especially in the context of exploration geophysics and subsurface analysis, several key performance indicators (KPIs) can be derived. These KPIs help in understanding the subsurface structures, assessing the quality of seismic surveys, and making decisions about potential resource extraction or other geotechnical applications. Here are some of the most important KPIs that can be calculated from seismic data:
# Signal-to-Noise Ratio (SNR)
- Definition: Measures the quality of the seismic signal relative to the background noise.
- Use: High SNR is critical for accurate interpretation of subsurface features.
- Categorization:
- Classification:
# Seismic Velocity
- Definition: The speed at which seismic waves travel through different layers of rock.
- Use: Helps in determining the types of rocks and their porosity, which is useful for resource exploration.
# Amplitude Variations
- Definition: Variations in the seismic wave amplitudes, often analyzed using Amplitude Versus Offset (AVO) techniques.
- Use: Can indicate changes in lithology, fluid content, or porosity in subsurface layers.
# Reflection Coefficient
- Definition: A measure of how much seismic energy is reflected at an interface between two rock layers.
- Use: Helps in identifying rock boundaries and the properties of those layers.
# Frequency Content
- Definition: Analyzing the frequency spectrum of seismic signals.
- Use: Lower frequencies penetrate deeper, while higher frequencies provide more detail of shallow structures. This KPI helps balance depth penetration with resolution.
# Seismic Attribute Analysis
- Definition: Attributes such as coherence, curvature, and instantaneous frequency are computed from the seismic data.
- Use: These attributes are used to highlight features such as faults, fractures, or fluid deposits.
# Travel Time
- Definition: The time it takes for seismic waves to travel from the source to the receivers.
- Use: Helps in building time-depth relationships for subsurface imaging.
# Stacking Velocity
- Definition: The velocity used in processing stacked seismic data to compensate for the effects of dipping layers.
- Use: Important for accurate imaging and correcting for distortions in the seismic reflection data.
# Porosity and Density Estimation
- Definition: Using seismic inversion techniques, porosity and density can be estimated from the seismic reflection data.
- Use: Critical for resource exploration, especially for identifying hydrocarbon reservoirs.
# Seismic Inversion Quality
- Definition: The accuracy of converting seismic reflection data into subsurface rock properties (e.g., impedance).
- Use: Determines the reliability of the inversion models used in resource estimation.
# Seismic Event Picking Accuracy
- Definition: The precision of identifying reflection events (peaks, troughs) in the seismic data.
- Use: Accurate picking is essential for detailed seismic interpretation and subsurface mapping.
# Seismic Data Coverage
- Definition: The extent to which the seismic survey area has been covered by seismic traces.
- Use: Ensures adequate coverage of the region of interest, reducing uncertainties in the final interpretation.
# Residual Moveout (RMO)
- Definition: The difference between the expected and observed travel times after migration.
- Use: Used to assess the quality of seismic migration, which corrects for the effects of dipping layers.
# Fault and Horizon Mapping Accuracy
- Definition: How well the seismic data can delineate subsurface faults and horizons.
- Use: Critical for structural interpretation, particularly in tectonically complex areas.
# Reservoir Characterization KPIs
- Definition: These KPIs include net pay thickness, fluid contacts, and hydrocarbon saturation derived from seismic data.
- Use: Important for evaluating the economic potential of oil and gas reservoirs. These KPIs can be computed through specialized software that processes and analyzes seismic data, transforming raw seismic traces into meaningful geological information.