On the Spot GIS: Geospatial Technologies Make Image-Based Mapping Truly Mobile September 8, 2008Posted by Bahadir Sahin in English, Haber (News).
Tags: image based mapping, imagery data, spatial analysis tools, spatial imagery
Companies that earn their money by extracting resources from below the ground have an enormous amount of work to do on the Earth’s surface before they can ever sink a spade or lower a drill bit, and most of that work is simply establishing an accurate picture of what that surface looks like.
Not only before exploration and production projects, but on an ongoing basis after pipeline production has begun, oil and gas companies need to continue to create and maintain reliable maps showing natural and man-made features and updates to existing facilities.
Technologies converging in the mapping space, such as global positioning systems, portable geospatial hardware, and image compression, are making field mapping considerably easier, and big companies such as Chevron and Enbridge are taking advantage of the benefits.
Chevron’s Technical Computing Information Management Group in Houston maintains an Oracle database that supports the wide variety of mapping projects that precede construction of pipelines, drill sites, gas plants, access roads and housing.
Nearly every project requires an exhaustive collection of surface data so that accurate analyses can be made of hydrology, hydrography, vegetative cover, soils, lithology and environmental conditions. Cultural features such as roads, buildings and houses must also be mapped with details relating to their size, condition and construction type. Richard Bosley, a Chevron GIS analyst, says that the information gathered by Chevron’s field crews is used “from the very early stage of scoping the project…all the way up to final as-builts.”
Until a few years ago, the recording of feature locations and collection of attribute data had to be performed manually by Chevron’s survey crews taking written notes. And the construction and maintenance crews of another company, Enbridge Inc., navigated its entire pipeline territory using paper maps. “This was a slow and frustrating process,” says Jason De Leon, a field designer in Enbridge’s Pampa office outside of Amarillo. “Often our field people were given coordinates for their destinations, but were not able to find those coordinates on the paper map. Also, the maps made by the Texas Department of Transportation did not necessarily show all the roads that we have up here. Crews spent a lot of time driving around in circles. You’d get instructions like, ‘Go to the windmill that’s losing one of its blades and turn right, then turn left when you see three cows.’”
Today, both companies do nearly all field mapping and navigation digitally.
Field work usually begins with a high-resolution satellite image. Bosley’s group at Chevron uses QuickBird images from DigitalGlobe of Longmont, Colo. Bosley stores as many as nine QuickBird scenes totaling 200 gigabytes on a portable hard drive and carries it with him to the project area. The 0.6-meter spatial resolution of these digital images makes them ideal base maps compared to vector line maps because surface features and land cover types as small as a manhole cover can readily be identified.
“Imagery is the backdrop for all of the work we do on the ground,” says Bosley.