| Popis: |
In the Ain Zalah field of northern Iraq broad epeirogenic movements were the style of tectonic activity through the Albian to lower Campanian. In the late Campanian-Maestrichtian two phases of syndepositional normal faulting created a regional horst-and-graben structural regime in the pre-upper Campanian rocks. In what is now the Ain Zalah structure, in the lower Shiranish, the first phase of faulting produced an east-northeast-west-southwest graben. This was followed in the late Shiranish by the second phase of faulting which again created a horst-and-graben type structure, but this time with northeast-southwest trends. There was no apparent movement on the first-phase fault system during the activity of the second phase of faulting. Following the end of the Cretaceous, he diastrophism reverted again to the epeirogenic style until the Taurus-Zagros orogenic folding of late Miocene-Pliocene time. This formed the present Jebel of Ain Zalah, which is a fairly steep-flanked, competently folded anticline. Thus, the near-vertical normal faulting of the Late Cretaceous was folded, leading to the interpretation that apparent reverse faulting in the structure is actually folded normal faulting. |
