On the genesis of the lead-zinc deposits in Nigerians Benue rift (
aulacogen) a re-interpretation.
In a larger-scale context, the Baltic dolerites and the alkaline rocks of northeastern Poland were preceded by magmatic activity in the Pripyat palaeorift in southern Belarus which represents the northwestern continuation of the Dnieper-Donetsk
Aulacogen in Ukraine.
The study area lies at the transition zone between the Arkoma Basin and the Ouachita orogenic belt and could also be associated with northwest trending faults associated with the southern Oklahoma
aulacogen [26, 27].
The basin fill thickens to the northeast, into the Oklahoma
aulacogen, and thins to the south and west, toward the Llano uplift and the Bend arch, respectively The Barnett Shale also thins to the west over the Bend arch where it interfingers with the Chappel Formation [14-17].
However, if they represent an
aulacogen (Failed-arm) type swarm (Fig.
Evolution of Nigeria's Benue Trough (
Aulacogen): A tectonic model: Geological magazine 112(6): 93-103.
Anomalies associated with Proterozoic structures include thicker crust (53 km) beneath the Kapuskasing uplift, a Paleoproterozoic intracratonic thrust (e.g., Percival, 1994), and thinner crust (35 km) beneath the Nipigon plate, a Mesoproterozoic
aulacogen developed on Superior Province basement.
The New Madrid fault zone is thought to be an
aulacogen - the failed arm of a plate tectonic rift system.
Evolution of the Nigeria's Benue Trough (
aulacogen): a tectonic model.
Tectono-sedimentological evolution of an elongate intracratonic basin (
Aulacogen): The case of the Benue Trough of Nigeria.
Thus, the negative DLFI zone outlined at the upper Amazon river
aulacogen may also infer a prospective sedimentary basin for oil and gas exploration.