The study area; Abakaliki and
its environs is of great geological importance due to its position in the Benue trough and the tectonic activities witnessed in the
area. It is underlain by shales of the
Abakaliki formation of the Albian
Asu River
Group. This study area is part of the Southern Benue Trough in the South
eastern part of Nigeria.
The Southern Benue Trough is part of the Benue
depression which comprises mainly the Abakaliki Anticlinorium and Afikpo
syncline to the east and the Anambra basin to the west.
The Asu River
Group was first described by Bain (1924) as lower Shales. Reyment (1965)
described the litho and biostratigraphy of the Asu River Group with its type
locality along Asu
River. A
middle Albian
age was assigned to the group by Reyment (1957) on the basis of ammonites such
as Oxytropidoceras hausa and Oxytropidoceras manuaniceras sp.
Deposition was under marine conditions giving rise to deposits of alternating
shales and siltstones with occurrence of sandstones.
A sequence of mafic
lavas, pyroclastic flows, tuffs and agglomerates forms part of the Cretaceous
succession within the Benue Trough of Nigeria. These volcanic rocks are
best exposed in the area round the interpretation of the different rock types
encountered, to reconstruct and interpret their depositional environments and
paleogrography by using the various lithofacies, their stratigraphic
relationship, structures and sedimentological character and paleontology. Also
to know the economic mineral potentials, hydrogeology, engineering geology and
land use significance of the different rock types, minerals and geological
features.