Crustal lineaments and shear zones in Africa: Their relationship to plate movements

doi:10.1016/0301-9268(84)90068-8

Precambrian Research

Volume 24, Issue 1, February 1984, Pages 27-45

https://doi.org/10.1016/0301-9268(84)90068-8 Get rights and content

Abstract

Many of the major lineaments in southern Africa are major ductile shear zones with large displacement, occurring within, though often bounding orogenic belts. An example is the boundary to the Limpopo belt in Botswana and Zimbabwe. However, some of these shear zones only record slight displacement when considered on a crustal scale; they are merely planes recording differential movement on much larger, flat to gently dipping, shear zones where the boundary to the orogenic belt is a low-angle thrust zone. These different types of shear zones are clearly shown in the Pan-African belt of Zambia where large ENE-trending lineaments have been recorded. Recent work has shown the northern group of shears to be large lateral ramps; for example, the rocks of the copper belt are part of an ENE-verging thrust package, the southern boundary of which is a major, oblique to lateral ramp. In southern Zambia shears are more analogous to major transform faults; they form as tear faults separating zones of different thrust vergence. A possible plate tectonic model is given for this part of Africa, showing the different relative plate movement vectors estimated from the geometry of the Pan-African shear zones.

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Research paperCrustal lineaments and shear zones in Africa: Their relationship to plate movements

Abstract

Precambrian Res.

J. Struct. Geol.

J. Struct. Geol.

Tectonophysics

J. Struct. Geol.

Structure, seismic data, and orogenic evolution of southern Canadian Rocky Mountains

Bull. Can. Petrol. Geol.

The Pre-Karroo geology of the Rufunsa area, Zambia with special reference to structure and metamorphism

Thrust systems

Am. Assoc. Petrol. Geol.

Tectonic displacements and thermal activity in two contrasting Proterozoic mobile belts from Greenland

Philos. Trans. R. Soc. London, Ser. A

The terminology of structures in thrust belts

J. Struct. Geol.

Archaean deformation patterns in southern Africa

Philos. Trans. R. Soc. London, Ser. A

The tectonic history of the Damaran Belt

Bull. Geol. Soc. S. Afr.

The movement pattern across the northern margin of the Limpopo mobile belt, southern Africa

Bull. Geol. Soc. Am.

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Can. J. Earth Sci.

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Bull. Can. Petrol. Geol.

Precambrian geology and structure in central Northern Rhodesia

Mem. Geol. Surv. N. Rhodesia

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Research paper
Crustal lineaments and shear zones in Africa: Their relationship to plate movements