MAASTRICHTIAN GREEN HOUSE IMPACT ON THE RUDIST RICH RESERVOIR WITHIN MIXED CARBONATES-SILICICLASTIC SUCCESSION, FROM KURDISTAN FORELAND AND PLATFORM, NE-IRAQ

The new discoveries of giant oil and gas fields from the last hydrocarbons frontier (kurdistan region.NE/Iraq) in the Middleast of great importance nowadays.Therefore, we pay attentions to the Maastrichtain green house impact on the Rudist rich reservoir from Kurdistan foreland and platform basin. Extensive field data along ten traverses and five wells have been integrated and correlated for the reconstructions of the biostratigraphic ,chronostratigraphic,and sequences stratigraphic frameworks.The Kurdistan foreland facies association changes during middle Maastrchtian from Flysch- turbidites to Rudist carbonates facies.While in kurdistan platform the Rudist reef was deposited in shallow warm marine water conditions, that shows progressive shallowing upwards without indications for forced regressions.The green house evolution shows outer,middle and inner ramp facies associations, that is combined by paleo depth and paleoshore line migrations.The outer ramp facies associations(150m,thick) is predominated by the large foraminifera (Lepidorbitoides socials var pustules,Orbitoides media, Orbitoides tissoti,Omphalocyclus macroporus, Loftuisa minor,and red algae).They are either bioclastic rich grindstone or packstone facies, alternated occasionally with Globotruncanides wackstone facies.The massive carbonate (345m,thick) of the middle ramp facies association is characterized by the abundance of Hippurites (Rudist), Acteonella, Graphyea, Glycemeris, Echinoidea and Green calc -algae (Cymopolia tebeticca, Cympolia kurdistanesis ).They found as Rudist Boundstone and Baffeslostone microfacies.The inner ramp facies associations(205m,thick) rich in green calc algae and benthonic foraminifea especially, Miliolides and soritoides.The inter and intera porosity, in all sections are mostly enhanced by the secondary porosity,especially the middle part.The green house condations are clearly impacts the shape, size,ornamentation, evolution trends and mass extinctions of most of the Maastrichtian faun as well as the reservoir characteritics.