Добірка наукової літератури з теми "Metamorphism (Geology) South Australia Lofty, Mount, Ranges"

The received wisdom was and is that landscapes cannot be more than a few millions of years old. Nevertheless, consideration of local geology and age of sediments in adjacent basins convinced Paul S. Hossfeld that the summit surface of low relief preserved on the northern Mount Lofty Ranges of South Australia resulted from long-continued planation and that it is of Cretaceous age; that is, some 70 million years old. Hossfeld's apparently intuitive suggestion that very old landscapes exist, recorded in his graduate thesis but not further pursued by him, is the earliest known statement of this idea.

"February, 2005"
Bibliography: leaves 259-272.
ix, 272 leaves : ill. (some col.), maps (col.), plates (col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
"The Mount Lofty Ranges and flanking St Vincent and Western Murray Basins preserve a rich record of Australian intraplate neotectonic movements and their effects of landscape evolution and sedimentary basin development in this region of South Australia." "The major goal of this study is to develop a new tectonic model that contributes to our fundamental understanding of how neotectonic motions and deformations operate within this sector of the southern Australian Earth crust. The other main aim of this thesis is to provide a better understanding of the effects those neotectonic movements imposed on landscape evolution and sedimentation." --Introd.
Thesis (Ph.D.)--University of Adelaide, Faculty of Science, School of Earth and Environmental Sciences, Discipline of Geology and Geophysics, 2005

This item is only available electronically.
The Mount Painter Province in the Northern Flinders Ranges, South Australia is composed of Palaeoproterozoic to Mesoproterozoic basement overlain by 7-12 kilometres of Neoproterozoic to Cambrian sedimentary rocks and is associated with high lateral geothermal gradients. During the Early Paleozoic, deformation and metamorphism reached greenschist to amphibolite facies during the ~500 Ma Delamerian Orogeny. This study focuses on the subsequent thermal history of the area by studying an E-W profile through the Mount Painter Province using the widely used techniques of structural mapping, micro-structural analysis and 40Ar/39Ar thermochronology to characterise and date deformation and cooling (as a proxy for exhumation). The E-W trending profile, known as the Hamilton Fault, is south dipping oblique slip with a normal and dextral component overprinted by younger brittle structures and brecciation which is seen in the structural and micro-structural analysis.. It is proposed to have a very active past and there is evidence of movement in the Adelaidean due to an apparent formation offset of ~600 m. The regional context of the Hamilton Fault having a dextral and normal component suggests an ε3 uplift, an ε2 extension SW to NE and ε1 NW-SE shortening. This is similar in character to the N-S shortening which is seen in the Alice Springs Orogeny (ASO). Results from the 40Ar/39Ar thermochronology show the basement metasedimentary rocks have cooling ages of around ~350 Ma between 300 to 400 °C and 312 Ma at 150 °C. Interestingly, the younger Adelaidean metasedimentary rocks have an older cooling age of 390 Ma between 300 to 400 °C. The thermochronology data suggests differential cooling has occurred. The observations suggest that exhumation is driven following the Delamerian folding event and forced the earlier cooling of shallower samples at a slower rate and later cooling of the deeper samples at a faster rate, a process caused by differential tilting. The cooling paths are well represented in this example as shown by converging cooling paths. Overall I attribute this subsequent thermal history and structural similarity to the ASO, a major widespread dramatic orogenic event which has not been widely recognized as a significant tectonic event in the Adelaide Fold Belt.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Earth and Environmental Sciences, 2010