Commercial accumulations of liquid hydrocarbons have remained elusive in East Africa, despite numerous shows and seeps. Could a reanalysis of the Petroleum Systems lead to renewed exploration?
Vol. 4, No. 5
Time-lapse seismic is now a proven technology for monitoring fluid movements and identifying undrained compartments in thick offshore clastic reservoirs. Several challenges still exist, however, in particular the use of the technology for carbonate and thin-bedded clastic reservoirs.
Reserve growth, the increase in successive estimates of recoverable hydrocarbons in existing fields, adds more oil to conventional reserves than new field discoveries. Large fields in mature petroleum provinces, it turns out, generally have the largest relative gains. Reserve growth appears to be the most important source for additional reserves in the United States, as explained in the article <a href="http://www.geoexpro.net/article/The_Reality_of_Reserve_Growth/b929e822.aspx" target="_blank">The Reality of Reserve Growth</a> written by Dr Mahendra K. Verma of the U.S. Geological Survey.
This is the ultimate experience for a keen geologist: Seven days of rafting through 300 million years of flat-lying sedimentary rocks of the Palaeozoic era and an intriguing record of Precambrian sedimentary and crystalline rocks. I doubt if there is a better way to get introduced to all kinds of rocks (sedimentary, magmatic and metamorphic) and geological processes. This is in particular true if you have a knowledgeable guide who lets you experience the pure joy of being in this nature’s wonder. If you ever get the chance, don’t miss it!
Logging While Drilling (LWD) is increasingly gaining popularity, with customers starting to look at drilling and evaluation services with a value-based, rather than a pure cost-based approach. GEo ExPro talked to Trond Graven in Baker Hughes INTEQ in Stavanger, Norway, about the status and future of LWD.
High-resolution, while-drilling electrical imaging provides a 360 degree map of the borehole wall in its most pristine state, before significant mud invasion and bore- hole degradation. This real-time information provides an instant look at the geology, essential to reservoir navigation and, for the first time, offers the definition needed for live geomechanical modeling.
Between 1995 and 2003, reserve growth from existing fields worldwide added three times more oil to conventional reserves than new field discoveries. Estimation of future reserve growth will be a critical factor for energy resource analysis.
The new assessment carried out by USGS indicates that northeastern Greenland may be a very important future petroleum province. If the mean estimate of 31 BBoE were discovered and proven, this huge basin would rank 19th out of the world’s 500 known petroleum provinces.
With exploration underway in almost every country in the continent, Africa is playing an important part in the exploitation of the world’s gas resources. Successful commercialisation of smaller fields, however, still presents challenges.