Geological Society of America, Abstracts with Programs; (United States), Mar 1, 1994
During the final phase of the Alleghanian Orogeny, which ended probably in the mid-Permian, inten... more During the final phase of the Alleghanian Orogeny, which ended probably in the mid-Permian, intense thrusting created a high mountain range with relief of up to 4.5 km and a width of 250--300 km. The drainage divide presumably lay within the Piedmont or Blue ridge Provinces, and probably ran subparallel to the present-day mid-Atlantic coastline. In the Middle and Late Triassic this mountain range was disrupted by the initial phases of rifting between the African and North American Plates. Many of the Alleghanian thrusts were reactivated as listric normal faults, creating a series of long, narrow asymmetric half grabens, and resulting in extensive delamination and thinning of the crust, particularly in the eastern Piedmont. South of the Salisbury Embayment the western limit of the Triassic basins steps consistently eastward, mirroring the offset of the ocean floor anomalies south of the Bermuda Fault Zone. The offset is also reflected by the easterly displacement of the present-day Appalachian drainage divide in southern virginia. This strongly suggests that the divide is largely inherited from the Triassic faulting episode. Rivers flowing westwards from the present-day Appalachians, including those like the New River crossing the Valley and Ridge Province, have retained more or less theirmore » pre-Triassic orientation, when they flowed down the western flanks of the Alleghanian mountains. The Triassic basins were separated by coast-parallel ranges with as much as 1 km of relief; these were largely eroded in the mid-Jurassic, so that by the Early Cretaceous the south-central Appalachians had more or less their present appearance. Subsequent erosion has probably resulted in westward retreat of the drainage divide.« less
Palaeolimnadiopsis bassi sp. nov. is described from the mid-Triassic Hawkesbury Sandstone of the ... more Palaeolimnadiopsis bassi sp. nov. is described from the mid-Triassic Hawkesbury Sandstone of the Sydney Basin, New South Wales. It is distinguished from other species of the genus by its paired growth lines, moderately large size, nonterminal umbo, and small larval valve. Macrolimnadiopsis, Pteriograpta, and Limnadia (Falsisca) are considered to be synonymous with Palaeolimnadiopsis, and Belgolimnadiopsis with Euestheria.
In salinity prone catchments, effective management of water resources involves balancing the requ... more In salinity prone catchments, effective management of water resources involves balancing the requirements of sustainable resource allocation with salinity mitigation programs and ecosystem protection. Understanding groundwater recharge and discharge processes is a key component to achieving this balance. In this study, surface and sub-surface features are linked with recharge and discharge processes by incorporating GIS and remote sensing mapping techniques
In salinity prone catchments, effective management of water resources involves balancing the requ... more In salinity prone catchments, effective management of water resources involves balancing the requirements of sustainable resource allocation with salinity mitigation programs and ecosystem protection. Understanding groundwater recharge and discharge processes is a key component to achieving this balance. In this study, surface and sub-surface features are linked with recharge and discharge processes by incorporating GIS and remote sensing mapping techniques
The East Antarctic Craton contains only one substantial outcrop of Palaeozoic–Mesozoic strata bet... more The East Antarctic Craton contains only one substantial outcrop of Palaeozoic–Mesozoic strata between 0° and 150°E; this lies in Mac. Robertson Land, on the eastern margin of the northern Prince Charles Mountains. These rocks are known as the Amery Group (Mond 1972, McKelvey & Stephenson 1990) and comprise dominantly fluviatile sandstones, with subordinate shales, coals and conglomerates. The lower formations of the Amery Group, the Radok Conglomerate and Bainmedart Coal Measures, contain a diverse Stage 5 palynomorph assemblage indicating a Baigendzhinian–Tatarian age (late Early–Late Permian, hereafter abbreviated as mid–Late Permian; Dibner 1978).
Journal of the Geological Society of Australia, Apr 1, 1981
A review of the large number of stratigraphically controlled isotopic age determinations relevant... more A review of the large number of stratigraphically controlled isotopic age determinations relevant to the Triassic shows that the ages of the Triassic‐Jurassic and Permian‐Triassic boundaries are approximately 200 Ma and 245 Ma, respectively. Estimates for the period boundaries within the Triassic are as follows: Norian‐Carnian—215 Ma; Carnian‐Ladinian—225 Ma; Ladinian‐Anisian—235 Ma; Anisian‐Scythian—240 Ma. Because of the many uncertainties inherent in these estimations, both stratigraphic and radiometric, the ages of the Triassic system and stage boundaries given above are assigned an error of ± 5 Ma.
... Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. We... more ... Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. Webb, J. and Fielding, CR (1999). Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. In AJ Miller and A. Gupta (Ed.), Varieties of Fluvial form (pp. ...
Geological Society of America, Abstracts with Programs; (United States), Mar 1, 1994
During the final phase of the Alleghanian Orogeny, which ended probably in the mid-Permian, inten... more During the final phase of the Alleghanian Orogeny, which ended probably in the mid-Permian, intense thrusting created a high mountain range with relief of up to 4.5 km and a width of 250--300 km. The drainage divide presumably lay within the Piedmont or Blue ridge Provinces, and probably ran subparallel to the present-day mid-Atlantic coastline. In the Middle and Late Triassic this mountain range was disrupted by the initial phases of rifting between the African and North American Plates. Many of the Alleghanian thrusts were reactivated as listric normal faults, creating a series of long, narrow asymmetric half grabens, and resulting in extensive delamination and thinning of the crust, particularly in the eastern Piedmont. South of the Salisbury Embayment the western limit of the Triassic basins steps consistently eastward, mirroring the offset of the ocean floor anomalies south of the Bermuda Fault Zone. The offset is also reflected by the easterly displacement of the present-day Appalachian drainage divide in southern virginia. This strongly suggests that the divide is largely inherited from the Triassic faulting episode. Rivers flowing westwards from the present-day Appalachians, including those like the New River crossing the Valley and Ridge Province, have retained more or less theirmore » pre-Triassic orientation, when they flowed down the western flanks of the Alleghanian mountains. The Triassic basins were separated by coast-parallel ranges with as much as 1 km of relief; these were largely eroded in the mid-Jurassic, so that by the Early Cretaceous the south-central Appalachians had more or less their present appearance. Subsequent erosion has probably resulted in westward retreat of the drainage divide.« less
Palaeolimnadiopsis bassi sp. nov. is described from the mid-Triassic Hawkesbury Sandstone of the ... more Palaeolimnadiopsis bassi sp. nov. is described from the mid-Triassic Hawkesbury Sandstone of the Sydney Basin, New South Wales. It is distinguished from other species of the genus by its paired growth lines, moderately large size, nonterminal umbo, and small larval valve. Macrolimnadiopsis, Pteriograpta, and Limnadia (Falsisca) are considered to be synonymous with Palaeolimnadiopsis, and Belgolimnadiopsis with Euestheria.
In salinity prone catchments, effective management of water resources involves balancing the requ... more In salinity prone catchments, effective management of water resources involves balancing the requirements of sustainable resource allocation with salinity mitigation programs and ecosystem protection. Understanding groundwater recharge and discharge processes is a key component to achieving this balance. In this study, surface and sub-surface features are linked with recharge and discharge processes by incorporating GIS and remote sensing mapping techniques
In salinity prone catchments, effective management of water resources involves balancing the requ... more In salinity prone catchments, effective management of water resources involves balancing the requirements of sustainable resource allocation with salinity mitigation programs and ecosystem protection. Understanding groundwater recharge and discharge processes is a key component to achieving this balance. In this study, surface and sub-surface features are linked with recharge and discharge processes by incorporating GIS and remote sensing mapping techniques
The East Antarctic Craton contains only one substantial outcrop of Palaeozoic–Mesozoic strata bet... more The East Antarctic Craton contains only one substantial outcrop of Palaeozoic–Mesozoic strata between 0° and 150°E; this lies in Mac. Robertson Land, on the eastern margin of the northern Prince Charles Mountains. These rocks are known as the Amery Group (Mond 1972, McKelvey & Stephenson 1990) and comprise dominantly fluviatile sandstones, with subordinate shales, coals and conglomerates. The lower formations of the Amery Group, the Radok Conglomerate and Bainmedart Coal Measures, contain a diverse Stage 5 palynomorph assemblage indicating a Baigendzhinian–Tatarian age (late Early–Late Permian, hereafter abbreviated as mid–Late Permian; Dibner 1978).
Journal of the Geological Society of Australia, Apr 1, 1981
A review of the large number of stratigraphically controlled isotopic age determinations relevant... more A review of the large number of stratigraphically controlled isotopic age determinations relevant to the Triassic shows that the ages of the Triassic‐Jurassic and Permian‐Triassic boundaries are approximately 200 Ma and 245 Ma, respectively. Estimates for the period boundaries within the Triassic are as follows: Norian‐Carnian—215 Ma; Carnian‐Ladinian—225 Ma; Ladinian‐Anisian—235 Ma; Anisian‐Scythian—240 Ma. Because of the many uncertainties inherent in these estimations, both stratigraphic and radiometric, the ages of the Triassic system and stage boundaries given above are assigned an error of ± 5 Ma.
... Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. We... more ... Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. Webb, J. and Fielding, CR (1999). Debris flow and sheetflood fans of the northern Prince Charles Mountains, East Antarctica. In AJ Miller and A. Gupta (Ed.), Varieties of Fluvial form (pp. ...
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