Structural geometry and evolution of the Rukwa Rift Basin, Tanzania: Implications for helium potential

The Rukwa Rift Basin, Tanzania is regarded as a modern example of cratonic rift zone despite complex polyphase extensional and episodic inversion structures. We interpret 2D seismic reflection data tied to wells identify describe structures controlling stratigraphic sequences (Late Carboniferous Pleistocene) in two main segmented domains, A B, which are controlled by the Chisi Saza shear zones. Fault geometry stratal patterns illustrated relation their kinematic interaction with folds. Fold reflect both compressional deformation were mapped particular interest for helium potential. illustrate fault bend folds, propagation folds monoclines that related extension events. Folds compression exhibit various structural styles reflecting at least phases widespread inversion. First, Early Jurassic phase involved multi-faulted anticlines Karoo strata. Second, mild during Pleistocene characterised symmetrical asymmetrical styles. Taken together, fold structures, juxtapositions unconformities define packages widely distributed form potential subsurface traps helium-nitrogen–rich gases, from some seep surface, evidently documented thermal springs across region.