Structural and stress analysis of the area between al-Akeider and mughayer as-Sirhan, Northwestern Badia-Jordan

Abstract EN

Major tectonic elements of Jordan have been investigated in many studies, in which attention was mainly given to the Dead Sea Transform fault and the associated deformation.

However, on a finer scale, our lack of knowledge about the geologic structures as well as the stress regimes of different parts of Jordan is an impediment to understanding the tectonic activities in detail.

In this regard, the present study presents the first structural results obtained from fault-slip data, extensional fractures and conjugate shear fractures of the Paleocene- Eocene rock units in northwestern Badia.In aggregate, 142 fault-slip data and 579 fractures were analyzed.

Results show that two stress regimes have been distinguished in the study area.

The first stress regime is strike-slip which is characterized by σ1SHmax oriented NNW-SSE and the second stress regime is extensional (normal faulting) in which σ1 is vertical, σ2(SHmax) and σ3(Shmin) is swinging mainly around NE-SW.

At least four stress states associated with these regimes were distinguished.

The first stress state is characterized by NNW- SSE σ1corresponding to the main compression direction in the study area and resulting in the formation of the folds and the related N-S sinistral and WNWESEdextral fault sets.

The other three states are of extension direction (σ3); the first is oriented NNE-SSW, and the second is oriented ENE-WSW.

These two trends correspond to the main extension defined during the Neogene.

The third extension direction is WNW- ESE to E-W which is related to a very late extensional event in Miocene to Pleistocene.