The Early–mid Cretaceous marks the confluence of three major continental-scale events in eastern Gondwana:(1)the emplacement of a Silicic Large Igneous Province(LIP)near the continental margin;(2)the volcaniclastic f...The Early–mid Cretaceous marks the confluence of three major continental-scale events in eastern Gondwana:(1)the emplacement of a Silicic Large Igneous Province(LIP)near the continental margin;(2)the volcaniclastic fill,transgression and regression of a major epicontinental seaway developed over at least a quarter of the Australian continent;and(3)epeirogenic uplift,exhumation and continental rupturing culminating in the opening of the Tasman Basin c.84 Ma.The Whitsunday Silicic LIP event had widespread impact,producing both substantial extrusive volumes of dominantly silicic pyroclastic material and coeval first-cycle volcanogenic sediment that accumulated within many eastern Australian sedimentary basins,and principally in the Great Australian Basin system(>2 Mkm^(3)combined volume).The final pulse of volcanism and volcanogenic sedimentation at c.105–95 Ma coincided with epicontinental seaway regression,which shows a lack of correspondence with the global sea-level curve,and alternatively records a wider,continental-scale effect of volcanism and rift tectonism.Widespread igneous underplating related to this LIP event is evident from high paleogeothermal gradients and regional hydrothermal fluid flow detectable in the shallow crust and over a broad region.Enhanced CO_(2)fluxing through sedimentary basins also records indirectly,large-scale,LIP-related mafic underplating.展开更多
The stratigraphy,sedimentary history and paleontology of the northern Eromanga Basin are reviewed in the light of extensive field effort,searching for Cretaceous vertebrate fossils,in particular dinosaurs.Prolonged no...The stratigraphy,sedimentary history and paleontology of the northern Eromanga Basin are reviewed in the light of extensive field effort,searching for Cretaceous vertebrate fossils,in particular dinosaurs.Prolonged non-marine deposition throughout the Jurassic was followed by Lower Cretaceous marine incursions which extended to the late Albian.Whilst biostratigraphy is underpinned by microfloral assemblages there are three distinct marine faunas preserved from the late Aptian,early middle Albian and late Albian.Effective regression caused by sediment oversupply in the latest Albian heralded the final phase of non-marine deposition in the Eromanga Basin which continued into the Cenomanian.A distinct floral assemblage is accompanied by a modest fossil vertebrate assemblage.展开更多
文摘The Early–mid Cretaceous marks the confluence of three major continental-scale events in eastern Gondwana:(1)the emplacement of a Silicic Large Igneous Province(LIP)near the continental margin;(2)the volcaniclastic fill,transgression and regression of a major epicontinental seaway developed over at least a quarter of the Australian continent;and(3)epeirogenic uplift,exhumation and continental rupturing culminating in the opening of the Tasman Basin c.84 Ma.The Whitsunday Silicic LIP event had widespread impact,producing both substantial extrusive volumes of dominantly silicic pyroclastic material and coeval first-cycle volcanogenic sediment that accumulated within many eastern Australian sedimentary basins,and principally in the Great Australian Basin system(>2 Mkm^(3)combined volume).The final pulse of volcanism and volcanogenic sedimentation at c.105–95 Ma coincided with epicontinental seaway regression,which shows a lack of correspondence with the global sea-level curve,and alternatively records a wider,continental-scale effect of volcanism and rift tectonism.Widespread igneous underplating related to this LIP event is evident from high paleogeothermal gradients and regional hydrothermal fluid flow detectable in the shallow crust and over a broad region.Enhanced CO_(2)fluxing through sedimentary basins also records indirectly,large-scale,LIP-related mafic underplating.
文摘The stratigraphy,sedimentary history and paleontology of the northern Eromanga Basin are reviewed in the light of extensive field effort,searching for Cretaceous vertebrate fossils,in particular dinosaurs.Prolonged non-marine deposition throughout the Jurassic was followed by Lower Cretaceous marine incursions which extended to the late Albian.Whilst biostratigraphy is underpinned by microfloral assemblages there are three distinct marine faunas preserved from the late Aptian,early middle Albian and late Albian.Effective regression caused by sediment oversupply in the latest Albian heralded the final phase of non-marine deposition in the Eromanga Basin which continued into the Cenomanian.A distinct floral assemblage is accompanied by a modest fossil vertebrate assemblage.
