Changes

===Callovian (about 164 Ma)===

===Callovian (about 164 Ma)===

The breakup of Pangea continued in Callovian time with spreading in the Central Atlantic and the complete detachment of Africa from North America (Figure 8). A rifting event along the future axis of the North Atlantic Ocean caused the development of a network of roughly parallel rift basins along the Iberian margin and Newfoundland. Oceanic crust was also forming between India and Arabia, following an Early Jurassic rifting stage. In the Tethys area the situation was more complex (Barrier and Vrielynck, 2008), due to the existence of an extensional regime in the west (spreading in the Alpine Tethys, also known as the Penninic Ocean) and to the south (spreading in the Mesogea Ocean) and to the onset of the Neo-Tethys subduction along the southern margin of Laurasia, which followed the docking of the peri-Gondwanan blocks with Laurasia in early Middle Jurassic time (Middle Cimmerian orogeny). The northward subduction of the Neo-Tethys was responsible for the development of a volcanic belt bordering to the north the subduction zone, whereas retro-arc basins formed between the margin of Laurasia and the volcanic arc. Sedimentation in the backarc basins ranged from deep to shallow marine carbonates and clastics. The opening of the Mesogea Ocean separated the margin of Arabia and North Africa from a major continental block, composed of a large carbonate platform and related peri-platform basins, which would later form part of the Turkish jigsaw and the Dinaride-Pelagonian blocks. The southern coast of the Mesogea Ocean was marked by coastal deposits along present-day northern Africa (Guiraud and Bosworth, 1999), whereas shelf carbonates were deposited on most of the eastern to southern Arabia. The latter, bordered to the north by the Mesogea Ocean, faced to the south the new oceanic seaway, which began to separate Arabia from India. This geodynamic position, between two extensional basins, probably favored the development of deep seaways (at least partially controlled by extensional tectonics, as the Arabian Basin) on the Arabian shelf.

The breakup of Pangea continued in Callovian time with spreading in the Central Atlantic and the complete detachment of Africa from North America ([[:file:M106Ch01Fig08.jpg|Figure 8]]). A rifting event along the future axis of the North Atlantic Ocean caused the development of a network of roughly parallel rift basins along the Iberian margin and Newfoundland. Oceanic crust was also forming between India and Arabia, following an Early Jurassic rifting stage. In the Tethys area the situation was more complex (Barrier and Vrielynck, 2008), due to the existence of an extensional regime in the west (spreading in the Alpine Tethys, also known as the Penninic Ocean) and to the south (spreading in the Mesogea Ocean) and to the onset of the Neo-Tethys subduction along the southern margin of Laurasia, which followed the docking of the peri-Gondwanan blocks with Laurasia in early Middle Jurassic time (Middle Cimmerian orogeny). The northward subduction of the Neo-Tethys was responsible for the development of a volcanic belt bordering to the north the subduction zone, whereas retro-arc basins formed between the margin of Laurasia and the volcanic arc. Sedimentation in the backarc basins ranged from deep to shallow marine carbonates and clastics. The opening of the Mesogea Ocean separated the margin of Arabia and North Africa from a major continental block, composed of a large carbonate platform and related peri-platform basins, which would later form part of the Turkish jigsaw and the Dinaride-Pelagonian blocks. The southern coast of the Mesogea Ocean was marked by coastal deposits along present-day northern Africa (Guiraud and Bosworth, 1999), whereas shelf carbonates were deposited on most of the eastern to southern Arabia. The latter, bordered to the north by the Mesogea Ocean, faced to the south the new oceanic seaway, which began to separate Arabia from India. This geodynamic position, between two extensional basins, probably favored the development of deep seaways (at least partially controlled by extensional tectonics, as the Arabian Basin) on the Arabian shelf.

[[file:M106Ch01Fig09.jpg|thumb|300px|{{figure number|9}}Global paleogeography (top) and major depositional settings in the southern margin of the Tethys (below) during Aptian time (about 120 Ma).]]

[[file:M106Ch01Fig09.jpg|thumb|300px|{{figure number|9}}Global paleogeography (top) and major depositional settings in the southern margin of the Tethys (below) during Aptian time (about 120 Ma).]]