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Seismic logistics operation map & Base camp mapping
Seismic logistics risk map (Source: WesternGeco)
Seismic operations are complex logistical undertakings. As such a logistics risk map will help identify potential hazards, obstacles, unsuitable terrain, sand dunes, and patches of dense vegetation that will impact on the operational process of a seismic crew. These maps are delivered on the project/license scale.
A seismic survey design aims at providing an acquisition geometry that is optimal for the geophysical goal whilst ensuring safety, meeting quality requirements and being financially viable. It is likely that there is a compromise between the ideal situation and restrictions placed by the terrain.
The selection process for locations suitable for use as base camps, fly camps, helipads and equipment drop zones needs to consider potential exposure to HSE (Health, Safety and Environment) risks and logistics planning by establishing the existing lay of the land and the current infrastructure in place.
HSE considerations will vary depending on the purpose of the location selected; however, the main points will include access, flood liability, any clearance required, sanitation and waste disposal, fuel storage and spill response mitigation and emergency response times to key locations around the project. Considerations for helipads and drop zones additional to the land clearance required include; elevation models, prevailing wind roses, tree height estimates and existing infrastructure like power lines (which all should be assessed when planning pad locations), fly away zones and long line corridors.
Logistics considerations include predicted travel time to various key locations throughout the project area to minimise both time exposure to risks travelling to and from any given operation area and to coordinate operations much more smoothly, with reduced travel times leading to more efficient and cost effective operations.
Understanding available access types and seasonal changes to their usability will help with decisions regarding the optimum time to conduct an operation, considering both risk exposure and potential time and cost savings.
A seismic logistics map is an integrated product in that the result is a cost map that uses a variety of products and aligns risk associated to each feature mapped. A seismic logistics risk map will help drive survey design, the scouting operation and daily operations on a seismic crew. The map should be flexible (meaning it has to be frequently updated) to adapt to changing conditions (access, weather, political etc.).
Known restrictions / limitations
Lifecycle stage and demand
Geographic coverage and demand
Global coverage (with a few restrictions see below). Demand in remote regions is high.
Input data sources
Optical: VHR1, VHR2, HR1, HR2, MR1
Spatial resolution and coverage
Spatial resolution: 1 m – 90 m pixel size
Minimum Mapping Unit (MMU)
Variable, depending on source data resolution MMU as small as 0.5 ha is possible.
Accuracy / constraints
Thematic accuracy: 80-90%
Spatial accuracy: The goal would be one pixel, but depends on reference data
Accuracy assessment approach & quality control measures
Stratified random points sampling approach utilizing in-situ measurements and any available published data or reports. Statistical confusion matrix with user’s and producer’s accuracy as well as kappa statistics for hydrological network and catchment area mapping.
Frequency / timeliness
Observation frequency: Archive data can be used although new acquisition may be a requirement in some situations. The frequency is constrained by client needs, satellite revisit and acquisition, but also processing requirements. Depending on the requirements of the customer the best suitable satellite sensor has to be chosen regarding spatial / spectral resolution as well as revisit frequency.
Timeliness of delivery: Delivery in time with project planning requirements. Archive data can be used to good effect if the prevailing conditions are known and the time of year is accounted for.
Delivery / output format
|Peer Review:||Hatfield Consultants|
Seismic logistics operation map & base camp mapping
# of Pages:
Internal – Project consortium and science partners
External – ESA
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