New data on deep-seated folding of Mesozoic series (by the example of Yevlakh-Agdzhabedinsky trough, Azerbaijan)

Geological and geophysical studies carried out in the second half of the last century on the north-eastern side of the Yevlakh-Agdzhabedinsky Trough revealed the oil and gas potential of the deep-seated Upper Cretaceous Mesozoic horizons and shallower Paleogene and Miocene series. Oil and gas bearing pay intervals are identified within Muradkhanli, Zardab, Shykhbagi, and Jafarli structures, which are the parts of the Zardab-Muradkhanli-Jafarli Tectonic Belt. Oil and gas occurrence is lithologically associated mainly with Upper Cretaceous fractured effusive and carbonate rocks, and also with Middle Eocene sedimentary-igneous rocks, and partially with Maykop-Chokrak terrigenous reservoirs belonging to structural traps. A number of researchers concluded that in favorable geological conditions on the northeastern side of the trough, the Mesozoic formations may also contain commercial oil and gas accumulations. Based on this, the bulk of exploratory drilling and geophysical investigations in recent years has been focused in the Yevlakh-Agdzhabedinsky Depression, where, in addition to the Paleogene-Miocene, the Mesozoic formations are widely developed. These studies resulted in updating the deep structural and tectonic architecture and petroleum potential of both southwestern and northeastern trough slopes. It was found that in accordance with hydrocarbon saturation, the northwestern and southeastern slopes differ from each other both in structural, tectonic terms, and in oil and gas potential, which is possibly related to different the Cenozoic and Mesozoic folding cycles