Calcareous nannofossil biostratigraphy of the marine Oligocene and Miocene succession in some wells in Northern Egypt

The Oligo–Miocene closure of the Tethys Ocean and evolution of the proto-Mediterranean Sea

“…5, Table S3), indicative of carbonate dissolution rather than a decrease in productivity 29,30 . Indeed, the sedimentary hiatus across the Serravallian is well documented in previous studies of marginal sites from this region 7,[31][32][33][34] , and although it was previously assumed to represent a sea level drawdown associated with the glaciation of Antarctica 27 , its occurrence in the deepwater Leviathan-1 and Dolphin-1 wells suggests the impact of additional processes. The approximate Mid-Miocene water depth at this site is estimated to be ~ 2.5 km 35 and hence it is unreasonable that this hiatus reflects subaerial exposure nor is it likely that the deepest part of the basin experienced significant sediment winnowing, particularly preferential winnowing of CaCO 3 .…”

Biostratigraphic re-evaluation of the lower to middle Miocene succession in the Eastern Carpathians: a case study related to the oil fields of the Diapir Fold Zone, Romania

“…Usu ally, the early Mio cene age given by the lab re ports is based on spe cies with wider strati graphic ranges, such as Helicosphaera ampliaperta (Bramlette and Wilcoxon) rang ing from the Aquitanian to Langhian, or Sphenolithus heteromorphus (Deflandre) rang ing from the Burdigalian to Serravallian (Lourens et al, 2004). These spe cies oc cur to gether at many sites from the Paratethys, Med i ter ra nean and At lan tic re gions (e.g., Shafik et al, 1998;Mãrunïeanu, 1999;Rögl et al, 2002;AEoriae et al, 2004;Faris et al, 2016;Melinte-Dobrinescu and Stoica, 2013;Sant et al, 2019;Ukpabi et al, 2020) as mark ers for the late Burdigalian NN4 (Mar tini, 1971) or MNN4a (Fornaciari et al, 1996) zones.…”