## 4 Tectonic Evolution and Sedimentary Filling of the Basin
### Basin Sedimentary Filling  
The sedimentary filling and evolutionary processes of basins are shaped by a blend of diversity and uniformity in their depositional history, alongside the influence of basin tectonic activities, structural evolution, and sea-level changes. These factors collectively dictate the sedimentary filling and evolutionary patterns within basins, highlighting the intricate interplay between geological processes and environmental conditions in shaping basin development [63]. The sedimentary basin in the North African Craton, such as the Triassic Basin, underwent Pan-Cratonic sedimentary filling during the Paleozoic Era, depositing strata from the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods. Similar to the entire Sahara Platform, the basin was profoundly influenced by the Caledonian orogen, resulting in an uneven uplift [64]. Earlier sedimentary layers experienced varying degrees of erosion, leading to a widespread absence of Permian strata in the basin (Figure 5). During this sedimentary period, the primary developments were marine facies and transitional marine-continental facies, which collectively exhibited six transgressive-regressive sedimentary cycles. During the Cambrian to Early Ordovician period, the basin was primarily characterized by tensile rupture rafts. During the Cambrian, extensive fluvial silicous sandstone deposits were formed in the basin. During the Early Ordovician, a marine transgression from Morocco to the east led to the deposition of a set of marine anoxic mudstone strata (Gassi mudstone). By the late Early Ordovician, a marine regression occurred, resulting in the deposition of shallow marine quartz sandstone, marking the first transgressive-regressive cycle from continental to marine in the Paleozoic Era. In the Middle Ordovician, the basin experienced another marine transgression, resulting in semi-deep marine Azzel mudstone deposition. During the Middle-Late Ordovician, a second marine regression occurred, leading to shallow marine clastic sandstone deposition in the early Late Ordovician, forming the basin's second marine transgression-regression sedimentary cycle in the Paleozoic Era. In the Late Ordovician, as the climate cooled, glaciers became widespread, causing sea levels to drop and leading to the deposition of low sea level glacial clastic rocks in the Paleozoic. Accompanied by an early Silurian marine transgression, reaching its maximum transgression, extensive shelf mudstone was deposited over the glacial sediments--Silurian marine radiolarian shale was widely deposited, which became an important (world-class) hydrocarbon source rock for the North African basin. In the late Silurian, influenced by the Caledonian orogen, there was a marine regression, leading to the deposition of siliceous clastic sandstone, marking the Paleozoic's third marine transgression-regression sedimentary cycle. During the Early to Middle Devonian, the basin experienced its fourth sedimentary cycle in the Paleozoic Era, forming the primary hydrocarbon source rocks in the Gudmis and Iiz Basins. The Upper Devonian to Lower Carboniferous saw the development of the fifth sedimentary cycle composed of marine transgression-regression elastic rock deposition. In the Middle to Late Carboniferous, the basin formed its sixth sedimentary sequence of clastic rock deposition due to marine transgression-regression (Figure 6). During the Mesozoic depression stage, the basin primarily developed terrestrial facies sedimentation interspersed with marine facies sediments. Figure 6: Evolution of Paleozoic sedimentary infill on the Sahara Plateau. During the early Sinian period, the continental crustal basement along the southeastern edge of the central and upper Yangtze regions underwent extension. By the middle of the Sinian period, the central and upper Yangtze regions transitioned into a stable passive continental margin. Entering the Early Cambrian, continental rifting intensified.