Changes

The latitude and relative position of the Pangea and the Tethys therefore favored the deposition of source rocks, whereas the continuous and time-transgressive generation and evolution of different sedimentary basins controlled the creation of reservoirs and traps (such as those related to tectonic inversion of extensional structures), leading to the impressive concentration of oil and gas fields in this area.

The latitude and relative position of the Pangea and the Tethys therefore favored the deposition of source rocks, whereas the continuous and time-transgressive generation and evolution of different sedimentary basins controlled the creation of reservoirs and traps (such as those related to tectonic inversion of extensional structures), leading to the impressive concentration of oil and gas fields in this area.

The distribution of giant oil fields is related to the nature of the sedimentary basins. According to Mann et al.,<ref name=Mannetal_2003>Mann, P., Gahagan, L, and Gordon, M. B., 2003, Tectonic setting of the world’s giant oil and gas fields, in M. T. Halbouty, ed., Giant oil and gas fields of the decade 1990- 1999: AAPG Memoir 78, 15-105.</ref> most of the giant oil and gas fields known until 2000 are related to continental passive margins facing the major ocean basins (34.66%), continental rifts and overlying sag basins (especially failed rifts at the edges or interiors of continents; 30.90%), and collisional margins produced by terminal collision between two continents (19.73%). These types of basins are common in the succession of North Africa and the Middle East. Due to the geodynamic evolution of this area, rift basins (mainly formed due to the opening of the Tethys oceans and to the extensional events affecting North Africa) rapidly evolved to passive margins (e.g., evolution of the peri-Gondwanan blocks) and then to active margins, with the development of collision-related basins (e.g., foredeep related to the accretion of the peri-Gondwanan blocks to the southern margin of Eurasia).

The distribution of giant oil fields is related to the nature of the sedimentary basins. According to Mann et al.,<ref name=Mannetal_2003>Mann, P., Gahagan, L, and Gordon, M. B., 2003, [http://archives.datapages.com/data/specpubs/memoir78/CHAPTER_2/CHAPTER_2.HTM Tectonic setting of the world’s giant oil and gas fields], in M. T. Halbouty, ed., Giant oil and gas fields of the decade 1990- 1999: [http://store.aapg.org/detail.aspx?id=1247 AAPG Memoir 78], 15-105.</ref> most of the giant oil and gas fields known until 2000 are related to continental passive margins facing the major ocean basins (34.66%), continental rifts and overlying sag basins (especially failed rifts at the edges or interiors of continents; 30.90%), and collisional margins produced by terminal collision between two continents (19.73%). These types of basins are common in the succession of North Africa and the Middle East. Due to the geodynamic evolution of this area, rift basins (mainly formed due to the opening of the Tethys oceans and to the extensional events affecting North Africa) rapidly evolved to passive margins (e.g., evolution of the peri-Gondwanan blocks) and then to active margins, with the development of collision-related basins (e.g., foredeep related to the accretion of the peri-Gondwanan blocks to the southern margin of Eurasia).

As a consequence, different types of sedimentary basins were continuously created by the movement of continental blocks, so that at any time different basin types can be recognized (e.g., divergence on the southern side of the Tethys and convergence on the Asian margin) in North Africa and the Middle East. Therefore, favorable conditions for the development of petroleum plays were almost continually present. Though there are some differences in tectonic evolution across the margin plate scale, correlations of stratigraphy and thus petroleum systems are possible.<ref name=Murris_1980 /> <ref name=Beydoun_1986 /> <ref name=Beydoun_1988 /> <ref name=Beydoun_1991 /> <ref name=May_1991 /> <ref name=Sharlandetal_2001 />

As a consequence, different types of sedimentary basins were continuously created by the movement of continental blocks, so that at any time different basin types can be recognized (e.g., divergence on the southern side of the Tethys and convergence on the Asian margin) in North Africa and the Middle East. Therefore, favorable conditions for the development of petroleum plays were almost continually present. Though there are some differences in tectonic evolution across the margin plate scale, correlations of stratigraphy and thus petroleum systems are possible.<ref name=Murris_1980 /> <ref name=Beydoun_1986 /> <ref name=Beydoun_1988 /> <ref name=Beydoun_1991 /> <ref name=May_1991 /> <ref name=Sharlandetal_2001 />