They concluded that HEGF is an effective and efficient method which can increase the oil production rate by a factor of 2 to 3. It has also been experimentally observed that HEGF is rather suitable for exploratory wells or wells with natural fissures around them (Yang et al. 1992; Wu et al. 2012).
To a certain extent, the conservative nature of the O&G industry is understandable, since it deals with high-risk, high-cost exploration projects with long return periods, and drilling of exploratory wells involves decisions with extremely high costs and risks, especially in frontier regions.
The British oil giant initially planned to drill four exploratory wells by 2017, with a further six wells by 2020, in an attempt to find what could be vast oil reserves in the Ceduna basin system that lies beneath the waters of the Great Australian Bight.
16 of the 17 exploratory wells are located in the area with hydrocarbon expulsion intensity greater than 50×104 t/km2.
With the oil price so low, the number of planned exploratory wells is down this year to between eight and 13, with appraisals below five.
Cairn Energy, a British company, has drilled several exploratory wells off Greenland in recent months, so far with little success.
Partnering with Great Britains Enterprise Oil Ltd., Enserch Exploration has targeted 10 to 12 new exploratory wells; if just 2 hit, the size of the company could double.
Over five years, Chevron says it hopes to conduct seismic surveys and to drill exploratory wells on a 1.6 million-acre area called the Oleska Block, which is heavy with shale rock deposits.
(The Railroad Commission's permits cover exploratory wells only).
Numerous oil companies have drilled 31 exploratory wells in Kenya over the last 50 years without success.
