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Full-Text Articles in Social and Behavioral Sciences
Late Quaternary Mega-Lakes Fed By The Northern And Southern River Systems Of Central Australia: Varying Moisture Sources And Increased Continental Aridity, T Cohen, G Nanson, John Jansen, B Jones, Z Jacobs, J Larsen, J.-H May, P Treble, D Price, A Smith
Late Quaternary Mega-Lakes Fed By The Northern And Southern River Systems Of Central Australia: Varying Moisture Sources And Increased Continental Aridity, T Cohen, G Nanson, John Jansen, B Jones, Z Jacobs, J Larsen, J.-H May, P Treble, D Price, A Smith
B. G. Jones
Optically stimulated and thermoluminescence ages from relict shorelines, along with accelerator mass spectrometer 14C ages from freshwater molluscs reveal a record of variable moisture sources supplied by northern and southern river systems to Lake Mega-Frome in southern central Australia during the late Quaternary. Additional lacustrine, palynological and terrestrial proxies are used to reconstruct a record that extends back to 105 ka, confirming that Lakes Mega-Frome and Mega-Eyre were joined to create the largest system of palaeolakes on the Australian continent as recently as 50-47 ka. The palaeohydrological record indicates a progressive shift to more arid conditions, with marked drying after …
On The Possible Origins Of An Unusual (Mid To Late Holocene) Coastal Deposit, Old Punt Bay, South-East Australia, Brian Jones, Adam Switzer, S Haslett, Dale Dominey-Howes, D Everett, C Courtney, B Mamo, L Strotz
On The Possible Origins Of An Unusual (Mid To Late Holocene) Coastal Deposit, Old Punt Bay, South-East Australia, Brian Jones, Adam Switzer, S Haslett, Dale Dominey-Howes, D Everett, C Courtney, B Mamo, L Strotz
B. G. Jones
An unusual coarse, shelly sedimentary unit is found elevated above present mean sea level in a sheltered pocket embayment at Old Punt Bay in south-eastern Australia. The coarse sediments, diverse microfauna, and large shelly macrofauna of mixed affinity suggest that the deposit is the result of high-energy deposition. The deposit was previously thought to have been deposited 1000-1300 cal bp based on one shell dated using 14C and amino acid racemisation. However, additional 14C dating indicates a likely age of ~2500 cal bp. Regardless of age constraints, the presence of rock-encrusting oyster shells and large articulated bivalves, suggests that the …
The Influence Of Palaeoenvironment And Lava Flux On The Emplacement Of Submarine, Near-Shore Late Permian Basalt Lavas, Sydney Basin (Australia), Paul Carr, Brian Jones
The Influence Of Palaeoenvironment And Lava Flux On The Emplacement Of Submarine, Near-Shore Late Permian Basalt Lavas, Sydney Basin (Australia), Paul Carr, Brian Jones
B. G. Jones
Lava flux and a low palaeoslope were the critical factors in determining the development of different facies in the Late Permian Blow Hole flow, which comprises a series of shoshonitic basalt lavas and associated volcaniclastic detritus in the southern Sydney Basin of eastern Australia. The unit consists of a lower lobe and sheet facies, a middle tube and breccia facies, and an upper columnar-jointed facies. Close similarities in petrography and geochemistry between the basalt lavas from the three facies suggest similar viscosities at similar temperatures. Sedimentological and palaeontological evidence from the sedimentary units immediately below the Blow Hole flow suggests …
Recognition Of Late Cretaceous Hasanbag Ophiolite-Arc Rocks In The Kurdistan Region Of The Iraqi Zagros Suture Zone: A Missing Link In The Paleogeography Of The Closing Neotethys Ocean, Sarmad Ali, S Buckman, K Aswad, B Jones, S Ismail, A Nutman
Recognition Of Late Cretaceous Hasanbag Ophiolite-Arc Rocks In The Kurdistan Region Of The Iraqi Zagros Suture Zone: A Missing Link In The Paleogeography Of The Closing Neotethys Ocean, Sarmad Ali, S Buckman, K Aswad, B Jones, S Ismail, A Nutman
B. G. Jones
The Hasanbag igneous complex is situated near Sidekan, 100 km northeast of Erbil city, Kurdistan Region, within the Iraqi Zagros suture zone. It forms part of an ophiolite-bearing terrane referred to as the "Upper Allochthon" or Gemo-Qandil Group. The Hasanbag igneous complex consists predominantly of calc-alkaline basaltic andesites to andesites cut by microgabbro and diorite dikes, which previously were interpreted as a part of the Eocene Walash volcanic group. However, 40Ar-39Ar dates on Hasanbag igneous complex kaersutite (magmatic hornblende) indicate an Albian-Cenomanian age (106-92 Ma). This reveals a previously unrecognized portion of the Late Cretaceous, Neotethyan ophiolite-arc complexes in the …