A new map of the Earth’s gravitational force based on satellite measurements may make it much less resource-intensive to find new oil deposits. The map could be particularly useful as the ice melts in the oil-rich Arctic regions. Ole Baltazar Andersen, senior scientist at DTU Space, the National Space Institute at the Technical University of Denmark, headed the development of the map.
The U.S. company Fugro, one of the world’s leading oil
exploration companies, is one of the companies that already have made use of
the gravitational map. The company now has initiated a research partnership
with DTU Space. "Ole Baltazar’s gravitational map is the most precise and
has the widest coverage to date,” says Li Xiong, vice president and head
geophysicist with Fugro. “On account of its high resolution and accuracy, the
map is particularly useful in coastal areas, where the majority of the oil is
Andersen’s map shows
variations in gravitational force across the surface of the Earth, and
knowledge about these small variations is a valuable tool in oil exploration.
Subterranean oil deposits are encapsulated in relatively light materials, such
as limestone and clay, and because these materials are light, they have less
gravitational force than the surrounding materials. Andersen’s map is based on satellite measurements and
has a hitherto unseen level of detail and accuracy. With this map, it is said
to be easier to find new deposits of oil underground.
The gravitational map from DTU Space is unique on account of
its resolution of only 2 km (about 1.24 miles) and the fact that it covers both
land and sea regions. Oil companies use the map in the first phases of oil
exploration. Previously, promising areas typically were selected using
protracted, expensive measurements from planes or ships. These areas appear
clearly on the map, and companies, therefore, can plan exploration much more
"The map will also be worth its weight in gold when the
ice in the Arctic seriously begins to melt, revealing large sea regions where it
is suspected that there are large deposits of oil underground. With our map,
the companies can more quickly start to drill for oil in the right places
without first having to go through a resource-intensive exploration
process," notes Andersen.
The success of the gravitational map is due in large
part to the fact that it is not based on direct gravitation measurements, but
on observations of the height of the sea, which reflects the gravitation.
"Height measurements have the advantage that it is possible to determine
the gravitational field very locally and thus make a gravitational map with a
resolution of a few kilometers. For comparison, the resolution of satellite
measurements of gravitational force typically is around 200 km (or 124 miles).
Satellite gravitation measurements are used, for example, to explore conditions
in the deeper strata of the Earth, but are not well suited to our
purposes," explains Andersen.
Satellites Reveal New Oil Finds
March 9, 2009