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Talos Dome is an ice dome on the edge of the East Antarctic plateau; it is adjacent to the Victoria Land mountains and overlies the eastern margin of the Wilkes Subglacial Basin. As part of the ITASE project, two traverse surveys were carried out in the Talos Dome area in November 1996 and January 2002. Airborne radar surveys were conducted in 1995, 1997, 1999 and 2001. Analysis of ERS-1 Radar Altimeter data allowed the positioning of Talos Dome about 50 km South of the 1960s location. A new plano-altimetric map of the Talos Dome area locates the dome culmination (159°04'21” E, 72°47'14” S, 2318.5 m) about 1.5 km north of the previous ERS-1 position. A surface strain network of nine stakes was measured using GPS in 1996, 1998 and 2002. Data indicates that ice at the TD site moves SSE a few centimetres per year. The other stakes move with radial velocities of 0.11 to 0.34 m a-1. The higher velocities are recorded in the steeper S-SW and E-NE slopes. Airborne radar measurements were carried out on 4320 km2 in the Dome area. Results indicate that the bedrock at the Talos Dome summit is about 400 m in elevation (WGS84) and that it is covered by about 1900 m of ice. Three hundred kilometres of snow radar (GPR) and GPS surveys show that the internal layering is continuous and horizontal up to 15 km from the dome, and highlight variations in the elevation of internal layers. The depth distribution analysis of layers reveals that accumulation decreases downwind of the dome (N-NE) and increases upwind (SSW). The palaeo-summit positions of the 4 layers are coherent and indicate that, over the past 500 years, the culmination of Talos Dome moved NNE at an average rate of about 1 m a-1. In order to calculate a preliminary age vs. depth profile for Talos Dome, a simple one-dimensional steady-state model was formulated; this model predicts that the ice 100 meters above the bedrock may cover more than one glacial/interglacial period (160-240 kyr).

This paper is aimed at mapping the submerged notch along the northeastern Adriatic coast and discussing the relations between the submerged notch, the seawater, the groundwater and the freshwater discharge along the coasts of the study area. Using hydrological and observational data collected during a solitary snorkel-swimming expedition along ~250 km-long route along the Istrian coasts and thermal and topographical data, we discuss the hydrogeological and topographical constraints on the origin and development of the submerged notch in the northeastern Adriatic Sea. The submerged notch was surveyed at depths ranging between -0.6 m m.s.l. and -2.6 m m.s.l. in the northern sector of the Gulf of Trieste (Italy), and at about -0.5/-0.7 m m.s.l along the Limski channel (Croatia). Along the Savudrija peninsula, a slightly carved submerged notch was surveyed at -0.5/-0.6 m m.s.l. The modern notch is completely lacking in the study area.Topographical data highlight that the submerged notch occurs in correspondence of plunging cliffs. Moreover, the submerged notch developed in correspondence of the submarine springs that allow mixing-zone dissolution. Data suggest that the mixing-zone dissolution, caused by the freshwater from submerged springs or from the largest rivers in the Gulf of Trieste, was a major factor in developing submerged notches. These new observations provide basic data for future studies on the development of the submerged notch along the northeastern Adriatic coast, previously linked almost exclusively to bioerosion. © 2014 Elsevier Ltd and INQUA.

Early geophysical studies hypothesized a continental rift structure beneath the Wilkes Subglacial Basin. Recent models favour a flexural origin for the basin linked to Transantarctic Mountains uplift and to East Antarctic Craton lithospheric rigidity. Flexural modelling predicts crustal thickening beneath the basin. Gravity modelling along the International Trans-Antarctic Scientific Expedition traverse (1998/99), however, reveals crustal thinning beneath the basin. At 75°S the crust thins from 37 km beneath the Transantarctic Mountains to 31 ± 2 km beneath the Wilkes Basin. The western flank of the basin features a sharp magnetic break. This signature may arise from a fault separating highly magnetic Precambrian craton crust from weakly magnetic Neoproterozoic(?) crust. Much later crustal extension may have focussed along the craton margin. The eastern flank of the Wilkes Basin exhibits a prominent aeromagnetic signature. Potential field modelling predicts 1-4 km thick sedimentary infill within the Wilkes extended terrane, interpreted mainly as Beacon Supergroup intruded by Jurassic Ferrar tholeiites. The adjacent Adventure Subglacial Trench is a narrow rift basin with 25±5 km thick crust and a 10±4 km sedimentary infill. © 2001 Elsevier Science B.V. All rights reserved.

An integrated study of onshore and offshore geology of the Ross Sea region (namely, Victoria Land, north of Ross Island, and the Ross Sea, Antarctica) has revealed a complex, post-Eocene tectonic framework. Regional NW-SE right-lateral, strike-slip faults are the outstanding feature of this framework and overprint an older Mesozoic extensional event, responsible for formation of N-S basins in the Ross Sea. The Cenozoic framework includes kinematic deformation and reactivation along the NW-SE faults, including formation of pull-apart basins, both positive and negative flower structures, and push-up ridges. N-S extensional faults are well developed between NW-SE faults and indicate E-W extension during the Cenozoic, produced by the NW-SE right-lateral strike-slip motion together with regional crustal extension. NNW-SSE compression, induced by the right-lateral, strike-slip kinematics, is indicated by locally inverted NE-SW faults and basins. The evolution, geometry, and location of the Rennick Graben and the Lanterman Range fit well into this model. Variations in the deformational style across the region can be linked to corresponding variations in the bulk crustal rheology, from brittle behavior in the west, to ductile deformation (at subseismic-scale resolution) near the Eastern Basin. A semibrittle region that favors N-S clustering of Cenozoic magmatic activity lies in between. In this region, Cenozoic volcanoes develop at the intersections of the NW-SE and the major N-S faults. The NW-SE faults cut almost continually from the Ross Sea to East Antarctica through lithospheric sectors with different rheology and thickness. At least two of the NW-SE faults correspond to older Paleozoic terrane boundaries in northern Victoria Land. The NW-SE faults link in the Southern Ocean with major transform faults related to the plate motions of Australia, New Zealand, and Antarctica.