The Oligocene represents a key interval during which coralline algae became dominant on carbonate ramps and luxuriant coral reefs emerged on a global scale. So far, few studies have considered the impact that these early reefs had on ramp development. Consequently, this study aimed at presenting a highresolution analysis of the Attard Member of the Lower Coralline Limestone Formation (Late Oligocene, Malta) in order to decipher the internal and external factors controlling the architecture of a typical Late Oligocene platform. Excellent exposures of the Lower Coralline Limestone Formation occurring along continuous outcrops adjacent to the Victoria Lines Fault reveal in detail the three-dimensional distribution of the reef-associated facies. A total of four sedimentary facies have been recognized and are grouped into two depositional environments that correspond to the inner and middle carbonate ramp. The inner ramp was characterized by a very high-energy, shallow-water setting, influenced by tide and wave processes. This setting passed downslope into an inner-ramp depositional environment which was colonized by seagrass and interfingered with adjacent areas containing scattered corals. The middle ramp lithofacies were deposited in the oligophotic zone, the sediments being generated from combined in situ production and sediments swept from the shallower inner ramp by currents. Compositional characteristics and facies distributions of the Attard ramp are more similar to the Miocene ramps than to those of the Eocene. An important factor controlling this similarity may be the expansion of the seagrass colonization within the euphotic zone. This expansion may have commenced in the Late Oligocene and was associated with a concomitant reduction in the aerial extent of the larger benthonic foraminifera facies. Stackingpattern analysis shows that the depositional units (parasequences) at the study section are arranged into transgressive-regressive facies cycles. This cyclicity is superimposed on the overall regressive phase recorded by the Attard succession. Furthermore, a minor highstand (correlated with the Ru4/Ch1 sequence) and subsequent minor lowstand (Ch2 sequence) have been recognized. The biota assemblages of the Attard Member suggest that carbonate sedimentation took place in subtropical waters and oligotrophic to slightly mesotrophic conditions. The apparent low capacity of corals to form wave-resistant reef structures is considered to have been a significant factor affecting substrate stability at this time. The resulting lack of resistant mid-ramp reef frameworks left this zone exposed to wave and storm activity, thereby encouraging the widespread development of coralline algal associations dominated by rhodoliths.
At the southern margin of the Central Anatolian Plateau (CAP), marine deposits that overlie the Central Tauride units at up to 2 km of elevation were used to constrain the onset of uplift to the middle‐late Miocene. This study demonstrates that much younger marine deposits cap the southern margin. We recognize the Last Common Occurrence of Neogloboquadrina spp. (sin) (0.61 Ma) and Pseudoemiliania lacunosa (0.467 Ma), which points to an early middle Pleistocene age. The benthic fauna indicates an epibathyal marine environment (400 to 500 m paleodepth), with an associated paleocoastline now at ~1,500 to 1,600 m above sea level. Our new results imply uplift rates of up to 3.21–3.42 mm/yr for the CAP southern margin since the deposition of the young marine units. In the area, the evaluation of late Pleistocene and Holocene uplift rates of ~1 mm/yr points to a post early middle Pleistocene short‐lived period of rapid uplift of the CAP southern margin, which can correlate the short‐lived surface uplift signal in numerical models of slab breakoff. Overall, this work demonstrates that the majority of the modern topography at the CAP southern margin (1,500 to 1,600 m) was only recently acquired, pointing to the absence of a significant orographic barrier along the southern plateau margin prior to 500 ka. The multiphased uplift recognized at the CAP southern margin by previous authors, as well as the fast uplift rate documented in this work, can be linked to lithosphere delamination and subsequent slab breakoff during the Arabian‐Anatolian continental collision.
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