2. Objectives
• Simple, flexible model to determine pipeline
routes
• A collaborative approach
• Open to use with various spatial datasets
• A methodology that can provide an auditable
approach
• Based on proven technologies
3. Data sources
• USGS Global GIS DVD
– Infrastructure (cities, gas fields etc.)
– Culture (road, rail, river etc.)
– Geology and land cover
– Slope and elevations
– Political and built-up areas
5. Map and model parameters
• Area of interest
– 41o49’N- 44o02'N / 68o06'E - 72o38'E
– S Kazakhstan across the border from Tashkent
– Gas refinery in Shymkent
– Gas field across Tien Shan mountains
• Projection
– UTM Zone 42N, WGS 84 datum69 ,oE central
meridian
• Factors
– Map scale = 1:1,000,000
– Map grid = 500 m
7. Cost surface
Vectors are first buffered (such as
proximity to roads or rivers)
Data are read as rasters (such as
elevation), or converted to raster (such
as buffers)
Data are classified according to factors
that translate into cost (such as granite
or wetlands being no-go zones)
All layers are then superposed into a
composite cost surface
9. Weighted overlay
All data are now grids.
(illustration from ESRI help files)
Each pixel of each theme is assigned
a suitability value - in this project,
the suitability values ranged from 0
to 20.
Some themes will have more
influence than others.
A composite map is produced,
showing the suitability ‘score’ for
each pixel.
11. Least cost path
Using the cost surface, the least cost
distance and directions are calculated.
These create cost directions from which
a cost path is derived.
Finally a vector representing the least
cost path becomes the proposed
pipeline.
As many environmental (such land use
classification) and physiographic ( such
as slope) factors as possible were thus
included.
13. Illustrations
Following are slides illustrating the process:
- Cost surface
- Routing model
- Various views in 3D
A movie from ArcGlobe also shows the full context
20. Results
• A costing model that can be made as
simple or as complex as warranted
• All data a geographically registered and
accurate for important distance, surface
and volume calculations
• This is applicable to many other aspects:
– E&P (seismic shot point and well positioning)
– Transportation (routing of ingress and egress traffic)
– Land use planning (positioning of various sites)
– Remediation (before-and-after state of areas)
