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Cenozoic tectonics in the Rennick Glacier area (northern Victoria Land, Antartica): Implications for the separation between East and West Antartica
No full textThe brittle structural architecture of the region between the Pacific Coast and the Outback Nunataks (northern Victoria Land, Antarctica): Integrating structural and fission track data
No full textWe report a synthesis of the structural data collected during the WISE campaign over northern Victoria Land, Antarctica. These data are integrated with the available apatite fission track data from the neighbouring regions to place new constraints on the kinematics and chronology of the brittle deformation along the eastern shoulder of the Wilkes Subglacial Basin. Brittle faulting is consistent with the regional Cenozoic tectonic pattern of north Victoria Land and responds to the increasing phases of denudation that accompanied extension/ transtension of the Rennick Graben flanks since 40-50 Ma. The discovery of pseudotachylyte-bearing fault rocks at the Pacific termination of the Rennick Graben is also reported for the first time. The dating of the pseudotachylyte-bearing fault zone opens new perspectives for the reconstruction of the brittle tectonic evolution of the region. Results coming from these studies combined with the analyses of the new samples collected for the fission track dating may generate permissive kinematic and geodynamic models for the Cenozoic tectonic evolution of the entire northern Victoria Land region
Raman microspectroscopy: a non-destructive tool for routine calibration of apatite composition for fission-track analysis.
No full textTectonic and denudational history of the Rennick Graben (northern Victoria Land): Implications for the evolution of rifting between East and West Antarctica.
No full textPolyphase structural evolution of northern Victoria Land (Antarctica) in the light of Gondwana break-up and the development of the Australia-New Zealand-Antarctica plate fragments (ANZAPF)
No full textThe Australia-New Zealand-Antarctica plate fragments (ANZAPF) evolved as consequence of break-up and
fragmentation of Gondwana since the late Early Jurassic. Antarctica occupied the centre of Gondwana, and
it thus holds a key position for any plate tectonic reconstruction. Northern Victoria Land (NVL) is located at
the Pacific end of the Transantarctic Mountains, a high-elevation mountain chain that stretches for >3500 km
from the Atlantic to the Pacific oceans across the entire Antarctic continent. The modern Transantarctic
Mountains represent the uplifted western shoulder of the Cenozoic West Antarctic Rift System. The main
uplift commenced around the Eocene-Oligocene boundary due to inversion of a wide mid-Jurassic to early
Paleogene sedimentary basin (“Mesozoic Victoria Basin”). The basement rocks of the Transantarctic
Mountains formed by orogenic processes due to subduction of the Palaeopacific Ocean beaneath East
Gondwana during the ?latest Ediacaran to early Palaeozoic Ross Orogeny. This long-lasting geological
history of NVL produced a highly anisotropic crust, which is very much susceptible to repeated reactivation.
Here, we present multi-methodological evidence for the polyphase structural evolution of NVL after initial
break-up of Gondwana in this region indicated by the ca. 180 Ma Ferrar volcanic event. A post-34 to 30 Ma
old, predominantly Neogene NW-SE striking dextral strike-slip belt with local transtension and transpression
has overprinted and in parts obliterated older structures and controls the present structural architecture of
NVL. It may be interpreted in terms of dynamic response to intra-oceanic fracture zone arrays between
Australia and Antarctica reaching into the NVL crust and extending further into the Ross Sea
The brittle structural architecture of the region between the Pacific coast and the Outback Nunatacks (northern Victoria Land, Antarctica): integrating structural and fission track data
No full textIn this paper we report a synthesis of the structural data collected during the WISE campaign on north Victoria Land, Antarctica. These data are integrated with the available apatite fission track data from the neighbour regions in order to place constraints to the kinematics and chronology of the brittle deformation along the western shoulder of the Wilkes Basin. Brittle faulting is consistent with the regional Cenozoic tectonic pattern of north Victoria Land and respond to the increasing phases of denudation that accompanied extension/transtension of the Rennick Graben shoulders since 40-50 Ma. The discovery of pseudotachylyte-bearing fault rocks at the Pacific termination of the Rennick Graben is also reported. The dating of the pseudotachylyte-bearing fault zone opens new perspectives for the reconstruction of the brittle tectonic evolution of the region. Results coming from these studies with the analyses of the new samples collected for the fission track dating may generate permissive kinematic and geodynamic models for the Cenozoic tectonic evolution of the entire northern Victoria Land region
Erosional patterns constrained by fission-track grain-age distribution of detrital apatites: preliminary results from the Po River modern sands.
No full textLong low-temperature thermal histories and zircon fission-track annealing: a case study from Corsica.
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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