Geophysical Mapping in Ethiopia

Geophysical Mapping in Ethiopia
MINERAL RESOURCES OF
Airborne geophysics has been carried
out during the last 50 years for
different purpose. The Govern ment
intents to cover the entire country
with low–medium resolution mapping.
Background
Basic geoscience mapping is helpful in
natural resources development, infrastructure
development, environmental
protection, natural hazard identification,
and for scientific research and education.
More systematic geoscience mapping in
the country began when the Geological
Survey of Ethiopia (GSE) was established
in 1968. The mapping was done either
independently by the Ethiopian government
or in collaboration with other international
organisations. Given the in -
creasing importance of geoscience mapping
for the public, the GSE recently reorganised
the internal procedures and integrated
regional geoscience mapping activities
into the ‘Basic Geoscience Mapping
Core Process’.
Rogers in 1951, Hunting in 1968 and
1971, Survair in 1970, Geosurvey in 1976,
Aeroservice in 1983, Dighern in 1993/94
and Geological Survey of Finland (GTK) in
1996 have carried out airborne geophysics
surveys in various parts of the country.
Airborne magnetics and radiometrics in
the 1970s were used for ore mineral exploration
and in the 1990s the coverage was
extended using airborne magnetics, radiometrics
as well as electromagnetics.
Magnetics was used for exploration of
petroleum in the Ogaden and Gambala
basins and for geothermal exploration in
the Afar Depression. Further magnetic surveys
were carried out in the Adola gold
field in the southern part of the Rift Valley
and in north and west Ethiopia.
These surveys cover 30% of the country.
For the last three to four decades,
Lake
Tana
High-grade Precambrian
Undifferentiated gneisses
and schists
Low-grade Precambrian
Metavolcano-sediments
Metaultramafic-mafics
Addis Ababa
Main Ethipoian Rift
Precambrian
Phanerozoic Intrusives
Gabbro
Diorite
Granite-tonalite
Palaeozoic Rocks
Tillites
Simplified geological map of Ethiopia.
1:500 000 scale land gravity survey coverage.
Mesozoic Rocks
Undifferentiated sediments
Geology: Modified from Mengesha et al.(1996)
Geological map of Ethiopia, second edition, 1:2,000,000
Cenozoic Rocks
Early-Mid Tertiary basalt
Upper Tertiary-Quaternary - basalt
Mid Tertiary-Quaternary - felsic rocks
Early Tertiary sediment
Upper Tertiary-Quaternary sediment

Airborne Surveys (purpose, flightline)
, 10
gold exploration, 0.2
hydrocarbon exploration, 3
hydrocarbon exploration, 4.8
hydrocarbon exploration, 5
hydrocarbon exploration, 7
hydrocarbon exploration, 8
mineral exploration (unspecified), 1
Capital
City
Regions
Dry Road
Main Road
Ministry of Mines of Ethiopia
Dear Investors,
MINERAL RESOURCES OF
Airborne geophysical (EM, Rad, Mag) survey coverage of Ethiopia.
gravity surveys on different scales have been
carried out in different parts of the country.
However, more systematic, regional gravity
surveys (1:500 000) were conducted from
1985 to 1996 in south and southwest
Ethiopia with the financial assistance of
SIDA/SAREC (the Swedish Government) and
in collaboration with the Geophysical Ob -
servatory of Addis Ababa University. From
2001, the GSE has independently conducted
the regional gravity survey. At present 80% of
the country is covered.
Future projects
km
0 50 100 200 300 400
The Ethiopian Government has approved a
five-year growth and transformation strategic
plan (2011-2015). In line with this strategic
framework it has been decided to:
• Cover the country by low–medium resolution,
airborne geophysical surveys
• Compile 1:500 000 scale gravity map of
Ethiopia
• Increase the coverage of the 1:250000
scale gravity map to 49%.
We take this opportunity to welcome you
to Ethiopia.
We promise to make every possible effort
to provide you with all required information
on the mineral sector in Ethiopia.
If you require information on the mining
law, licensing conditions and the investment
climate in Ethiopia, please contact
the Mineral Licensing and Administration
Department:
Ministry of Mines
Mineral Licensing and Administration
Department
P.O. Box 486
Addis Ababa, Ethiopia
Tel. +251 11 6461214
Fax +251 11 6463454
Email: information@mome.gov.et
www.mome.gov.et
The plane used by the Geological Survey of Finland
(GTK) for airborne geophysical measurements.
Photos. Kai Nyman.
If you require information on the geology
and mineral opportunities in Ethiopia,
please contact the Geological Survey of
Ethiopia (GSE):
Geological Survey of Ethiopia
P.O. Box 2303
Addis Ababa, Ethiopia
Tel. +251 6 463325
Fax +251 6 463326
Future geoscience mapping projects.
Email: Survey@ethionet.et
www.geology.gov.et
We are looking forward to your mining
investment in Ethiopia.
Prepared with assistance from GEUS.
December 2010