GPS as a geodetic tool for geodynamics in northern Victoria Land, Antarctica

The VLNDEF (Victoria Land Network for DEFormation control) project started in 1999 with the aim of detecting crustal deformation in Northern Victoria Land (Antarctica) over an area that had never been surveyed by a dense GPS network before. After a brief summary of the Italian geodetic activities carried out since 1991, the paper presents the results obtained from the processing of data collected from 1999 to 2003. In particular, processing strategies were dealt with, in order to produce horizontal and vertical displacement maps through GPS observations. Absolute motions in a global reference frame have been investigated using a double approach, which allowed us to make considerable progress in detecting movements and standardizing the data analysis. The analyses provide absolute horizontal velocities ranging between 17 mm yr−1 and 8 mm yr−1, with greater motions in the northernmost area. The subtraction of the rigid plate motion provides relative displacements, which may contribute to the understanding of neotectonics and geology, whereas the pattern of the vertical crustal motions detected, with average values of +1.3 mm yr−1, is essential to detect the effect of Glacial Isostatic Adjustment (GIA) and other geophysical signals, and to redefine theory and numerical models used without any direct measurements.

[1]  Walter H. F. Smith,et al.  Free software helps map and display data , 1991 .

[2]  Geoffrey Blewitt,et al.  Crustal displacements due to continental water loading , 2001 .

[3]  W. Peltier,et al.  Ice Age Paleotopography , 1994, Science.

[4]  C. Zweck,et al.  West Antarctic Ice Sheet Elevation Changes , 2013 .

[5]  Axel Rülke,et al.  Plate kinematics and deformation status of the Antarctic Peninsula based on GPS , 2004 .

[6]  L. Mervart,et al.  Bernese GPS Software Version 5.0 , 2007 .

[7]  E. Ivins,et al.  Lateral viscosity variations beneath Antarctica and their implications on regional rebound motions and seismotectonics , 2004 .

[8]  Geoffrey Blewitt,et al.  Effect of annual signals on geodetic velocity , 2002 .

[9]  Alessandro Capra,et al.  Terra Nova Bay GPS permanent station (Antarctica): data quality and first attempt in the evaluation of regional displacement , 2005 .

[10]  R. Dach,et al.  ITRF coordinates and plate velocities from repeated GPS campaigns in Antarctica – an analysis based on different individual solutions , 2001 .

[11]  T. Tin,et al.  Geophysical Research Abstracts , 2007 .

[12]  Francesco Salvini,et al.  Cenozoic tectonic lineaments of the Terra Nova Bay region, Ross Embayment, Antarctica , 1999 .

[13]  Y. Bock,et al.  Anatomy of apparent seasonal variations from GPS‐derived site position time series , 2001 .

[14]  Stephen Lichten,et al.  Gipsy-Oasis II: A High Precision GPS Data Processing System and General Satellite Orbit , 1995 .

[15]  E. Ivins,et al.  Antarctic glacial isostatic adjustment: a new assessment , 2005, Antarctic Science.

[16]  Michael B. Heflin,et al.  Quasi-continuous global positioning system measurements of glacial , 2004 .

[17]  Richard G. Gordon,et al.  No-net-rotation model of current plate velocities incorporating plate motion model NUVEL-1 , 1991 .

[18]  F. Storti,et al.  Structural architecture and displacement accommodation mechanisms at the termination of the Priestley Fault, northern Victoria Land, Antarctica , 2001 .

[19]  Richard G. Gordon,et al.  Current plate motions , 1990 .

[20]  Zuheir Altamimi,et al.  ITRF2000: A new release of the International Terrestrial Reference Frame for earth science applications , 2002 .

[21]  E. Ivins,et al.  Predictions of Antarctic crustal motions driven by present-day ice sheet evolution and by isostatic memory of the Last Glacial Maximum , 1998 .

[22]  Francesco Salvini,et al.  Cenozoic geodynamics of the Ross Sea region, Antarctica: Crustal extension, intraplate strike-slip faulting, and tectonic inheritance , 1997 .