COMMISSION XIV:

“CRUSTAL DEFORMATION”

 

S. Zerbini

 

The Terms of Reference of the Commission on Crustal Deformation (Commission XIV) are described in the following.

 

Space geodetic measurements provide nowadays the mean to observe deformation and movements of the Earth’s crust at global, regional and local scale. This is a considerable contribution to global geodynamics by supplying primary constraints for modeling the planet as a whole on the one hand, but also for understanding geophysical phenomena occurring at smaller scales. There are many geodetic signals, which can be observed and are representative of the deformation mechanisms of the Earth’s crust at different spatial and temporal scales. The time scales range from seconds to million of years in the case of plate tectonics and from millimeters to continental dimension for the spatial scales.

 

Gravimetry, both absolute and relative, is a powerful tool providing information to the global terrestrial gravity field and its temporal variations. Superconducting gravimeters allow a continuous acquisition of the gravity signal at a given site with precision of 10-10. This is important in order to be able to detect and model environmental perturbing effects as well as the weak gravity signals associated with vertical crustal movements of the order of mm/yr.

 

These geodetic observations together with other geophysical and geological sources of information provide the mean to understanding the structure, dynamics and evolution of the Earth system.

Commission XIV comprises the following sub-Commissions:

 

1.       Working group of European Geoscientists for the Establishment of Networks for Earth science Research (WEGENER, Chair: Luisa Bastos, Portugal);

  1. Geodetic and Geodynamics programs of the Central European initiative (CEI, Chair Janusz Sledzinski, Poland);
  2. Asia-Pacific Space Geodynamics program (APSG, Chair: Ye Shuhua, China);
  3. Central and South America (Co-Chairs: Alejandro Gutiérrez, Costa Rica and Rodrigo Barriga, Chile);
  4. Africa (Chair: Ludwig Combrink, South Africa);
  5. Antarctica (Chair: Alessandro Capra, Italy);

 

encompassing most of the tectonically active areas of the Planet. The sub-Commissions deal with main scientific objectives having common general aspects and, in parallel to these objectives, follow the development of technology and measurement techniques capable to best fulfil the scientific objectives. This allows a close interaction between the various sub-Commissions, which shall organize, on a regular basis, conferences or assemblies of the sub-Commissions themselves or, for selected scientific and technological subjects of common interest to most of them.

 

Primary, general objectives of Commission XIV are:

 

Commission XIV has the following structure:

Bureau

 

President:

          Susanna Zerbini (Italy, zerbini@df.unibo.it)

Vice-Presidents:

          Hans-Gert Kahle (Switzerland, hans-gert.kahle@geod.baug.ethz.ch)

          Bernd Richter (Germany, bernd.richter@bkg.bund.de)

Secretary:

          Tonie VanDam (Luxembourg, tvd@ecgs.lu)

 

Members:

          Rodrigo Barriga (Chile) rbarriga@igm.cl

          Luisa Bastos (Portugal) lcbastos@oa.fc.up.pt

          Geoffrey Blewitt (USA) gblewitt@unr.edu

          Yehuda Bock (USA)         ybock@ucsd.edu

          Claude Boucher (France) boucher@ensg.ign.fr

          Carine Bruyninx (Belgium) C.Bruyninx@oma.be

          Eric Calais (France) calais@faille.unice.fr

          Alessandro Capra (Italy) alessandro.capra@mail.ing.unibo.it

          Ludwig Combrink (South Africa) ludwig@hartrao.ac.za

          James Davis (USA)           jdavis@cfa.harvard.edu

          Martine Feissel (France) feissel@ensg.ign.fr

          Alejandro Gutiérrez           (Costa Rica) gechever@una.ac.cr

          Michael Pearlman (USA) mpearlman@cfa.harvard.edu

          Christoph Reigber (Germany) reigber@gfz-potsdam.de

          Robert Reilenger (USA) reilinger@erl.mit.edu

          Hans-Geog Scherneck (Sweden) hgs@oso.chalmers.se

          C. K. Shum (USA) ckshum@osu.edu

          Janusz Sledzinsky (Poland) sledzinski@gik.pw.edu.pl

          Shuhua Ye(China) ysh@center.shao.ac.cn

 

Activities 1999-2003

 

The Commission XIV Bureau met on four occasions:

·    September 21, 2000, San Fernando, Spain;

·    December 17, 2000, San Francisco, USA;

·    March 29, 2001, Nice, France;

·    September 4, 2001, Budapest, Hungary.

 

The last Bureau meeting will take place in July 2003, in Sapporo, during next IUGG.

 

During the first meeting, the Board membership, Subcommissions organization and Commission activities were discussed and revised. During the subsequent meetings particular attention was given to support and coordinate the work carried out by the Subcommissions. In particular, the Bureau agreed that a major activity of Commission XIV be the support to the formation of a global "velocity field" from the combination of regional contributions along the lines of the GPSVEL Project (see WEGENER section of this report).

 

A meeting with the representatives of the Central (including the Caribbean area) and South America Subcommission took place in Miami prior to the December 2000 Bureau meeting in San Francisco. They agreed to survey the relevant activities underway and the resources available. The South America co-chair announced the international Symposium on "Recent Crustal Deformation in South America and Surrounding Areas". This event, supported by the Commission took place in Santiago, Chile, in October 2002 (see South America section of this report).

 

Commission XIV co-sponsored the "Tenth International Symposium on Recent Crustal Movements held in Helsinki, Finland, August 27-31, 2001. There were more than 70 participants in the symposium and 60 presentations covering a wide variety of topics. As a result, a special issue of the Journal of Geodynamics (2003) has been produced containing 13 manuscripts.

 

Commission XIV has a web site at the following address: http://www.df.unibo.it/commXIV/.

 

In the following the activities of the Subcommissions are described.

 

Publications

          Journal of Geodynamics, Special Issue, Crustal Deformation, 2003, vol. 35 N. 4-5.

 

WEGENER

 

During the period 1999-2003 the main objectives of the WEGENER sub- commission were maintained. Therefore, the activities were centered on:

·    study of the three-dimensional deformations and gravity along the African-Eurasian plate boundaries and in the adjacent deformation zones in order to contribute to a better understanding of the associated geodynamical processes;

·     monitoring of three-dimensional deformations in a large region centered around Fennoscandia in order to determine the magnitude and extent of the present-day postglacial rebound in that area, thereby extending our knowledge about the viscoelastic properties of the Earth;

·    investigation of height and sea-level variations in order to identify and separate the processes contributing to these variations.

 

Within this period the WEGENER board had the following meetings:

·    Nice, France, April, 27, 2000;

·    San Fernando, Spain, September, 21, 2000;

·    Nice, France, March 26, 2001;

·    Budapest, Hungary, September, 5, 2001;

·    Athens, Greece, June 14, 2002.

 

The main decisions and outcomes of these meetings were:

 

·    to promote the cooperation of researchers from different geosciences and to strengthen the cooperation with African research groups with enlargement of activities in Africa;

·    to support the GPSVEL project, managed by Geoffrey Blewitt, by promoting the interest and willingness to provide GPS data/solutions within the WEGENER area of interest. As a result, several contributions were sent including solutions from more than 100 stations distributed all over Europe;

·    to support the interest for the realisation of a coordinating Center that could produce "WEGENER solutions" mainly (but not exclusive) from permanent GPS stations and episodic campaigns. There was agreement on the realisation of such a center that should also address issues such as data quality and control and comparison of processes and products. As a first step, the WEGENER Directing Board decided to start the setup of a Data Base Center supporting the generation of a detailed velocity field in the WEGENER study area. This may be seen as a part of the global GPSVEL-Project (Blewitt et al., 2000).

 

This project should start with the collection and combination of GPS and other solutions for coordinates and/or velocity estimates. The center should act in order to guarantee the quality for non-IGS or non-EUREF sites, and should not superimpose, but be complimentary to these Services, by dedicating also special attention to the use of GPS data from episodic campaigns.

 

A second step should be the application of an integrated approach to a selected region where data from different geosciences would be jointly analyzed and interpreted.

 

A first a document entitled “Processing and Submission Guidelines for GPS Solutions to be integrated to a WEGENER Data Base” was prepared by Matthias Becker, Carine Bruyninx and Rui Fernandes to be disseminated among potential contributors. This document contains guidelines and requirements to be followed for submission of solutions to such a Center and concentrates on how GPS campaigns of finite duration can be processed and correctly tied to the ITRF. It was first delivered to the participants of the 11th General Assembly of the WEGENER project that took place in Athens in June 2002.

 

During the period 1999-2002, two General Assemblies were organized. One took place at San Fernando, in Spain, in September 2000, hosted by the Real Instituto Y Observatorio de la Armada, and the other one at Vouliagmeni (Athens), in Greece, in June 2002, hosted by the Department of Rural and Surveying Engineering of the National Technical University of Athens. The main themes for these Assemblies were:

·    Geodynamics;

·    Plate tectonics;

·    Integrated observation techniques.

 

Two special issues of international journals were produced. In 2000, the Journal of Geodynamics published a special issue, which compiles six manuscripts resulting from presentations made during the eighth WEGENER general assembly. In 2002, a special issue of Global and Planetary Change was published dealing with height and sea-level variations resulting from the SELF II project .

 

One concern in the organization of these Assemblies was to bring together researchers from different disciplines (geodesy, geophysics, geology, seismology, etc.) in order to contribute to merge expertise and solutions towards a more comprehensive and correct interpretation of the analysis results.

 

Special support was given to the participation of Colleagues from North African Countries. Pursuing the goal of taking the general Assemblies to different countries of the WEGENER area, and with the purpose to strengthen the cooperation with North Africa, there was a proposal for organizing the next WEGENER Assembly in a North African Country. The Colleagues from Morocco kindly agreed to host the next (12th) general assembly in 2004.

 

Publications

Blewitt G., Lavallée D., Clarke P.J., Nurutdinov, Holt W.E. Kreemer C., Meertens C.M. Shiver W.S., Stein S., 2000, GPSVEL Project: Towards a Dense Global GPS Velocity Field. In Book of Extended abstracts of the 10th General assembly of the WEGENER Project, San Fernando, Spain, 18-20 September 2000, Boletin ROA, N.3/200,

 

Journal of Geodynamics, 2002, Special Issue WEGENER: Observations and Models, vol. 30, N. 3, pp.287-388.

 

Global and Planetary Change, 2002, Special Issue Sea Level Fluctuations in the Mediterranean: Interactions with Climate Processes, vol. 34, N. 1-2, pp 1-140.

 

Geodetic and Geodynamic Programs of the Central European Initiative (CEI)

 

Plan of action of the CEI Section C "Geodesy" includes:

·    realisation of the Project CERGOP (Central Europe Regional Geodynamics Project) and post-UNIGRACE (UNIfication of GRAvity system in Central and Eastern european countries) actions;

·    activities of 13 CERGOP Study Groups;

·    activities of the CEGRN (Central European GPS Reference Network) Consortium and

·    actions of two Section's Working Groups on University Education Standards and on Satellite Navigation Systems;

·    cooperation with the European Geophysical Society (EGS).

·     

The first phase of the Project CERGOP was concluded in 1998. Since 1998 the second phase of the Project is being realized. The proposal of the second phase of the Project CERGOP-2 "A Multipurpose and Interdisciplinary Sensor Array for Environmental Research in Central Europe (CERGOP-2/Environment)” was selected by the European Commission and will be financially supported during the next three years. Fourteen European countries participate in the second phase of the project and the total number of CERGOP-2 stations is 63. About 30 CERGOP-2 points are permanent stations that are also contributing to other international projects. Many CEGRN sites are part of the IGS permanent network. Some CERGOP Processing Centers are also EUREF Local Analysis Centers (EUREF LOC) and process routinely data for the EPN (European Permanent Network). Monitoring GPS CEGRN campaigns were performed in 1999 and 2001 (CERGOP-2). Next campaign is scheduled for 2003. Five CERGOP Processing Centers compute velocity vectors of the stations in the Central European area. One of the main parts of the international activities within the CERGOP project is the work of CERGOP Study Groups (CSG). At present, there are 13 study groups covering particular fields of activity supporting the realisation of the Project and, in general, they form the relevant ”workpackages” of the EU Project CERGOP-2/Environment. In particular, the activities of seven study groups concern the geodynamics of particular European regions such as the Eastern Alps and the North and Eastern Adriatic Sea, Romania Plate, Pannonian Basin, Plitvice Lakes/Croatia, Tatra Mountains, Northern Carpathians and Balkan Peninsula. A set of eight volumes of geotectonic monographs was published; the publications include the main scientific results obtained for the regions studied by CERGOP study groups and summarize the main achievements of all studies. Suggestions are also presented for the further continuation by means of advanced technologies.

 

The CERGOP was an impulse for establishment of the CEGRN Consortium of institutes involved in the realisation of the Project. The Consortium was created with the aim to maintain, currently upgrade and develop the CEGRN established in the frame of CERGOP, as well as to perform coordinated monitoring of satellite CEGRN campaigns and to organize and maintain the CEGRN (CERGOP) Data and Processing Centers. The Consortium will also be a seedbed of new European projects and initiatives. At the moment 14 European institutions are members of the Consortium.

 

The UNIGRACE project was launched in 1997 as multipurpose interdisciplinary project and it ended in 2002. It consisted in the establishment of absolute gravity stations covering the area from the Baltic Sea to the Adriatic and the Black Seas.  It constitutes an excellent frame for the connection of the national gravimetric networks and it provides a unified precise gravity frame in Central and Eastern Europe linked to the Western European network. Ten absolute gravity intraplate and seven tide-gauge stations were measured in 12 countries. The gravity observations were carried out by means of five absolute gravimeters from Austria, Finland, France, Germany and Poland. The observation campaigns of the UNIGRACE project were successfully performed in 1998/1999 and 2000/2001. The analyses of the gravity data of the UNIGRACE campaigns indicate that there are unclear considerable changes of the gravity values at some absolute stations. These changes cannot be explained by accounting for the effects of station point displacements, water table level variations, atmospheric effects or other known factors. For this reason, all countries participating in UNIGRACE agreed to continue, as a UNIGRACE follow-up action, the further investigation of the gravity time variations/change at main European stations. In 2003, a detailed programme of the project will be adopted and the funding aspects will be discussed as well.

 

Section C Working Group on University Education Standards organizes yearly an international educational seminar/workshop or symposium. The subjects of these events include satellite DGPS techniques and field training for application to different geodetic purposes. Lately the WG has initiated close cooperation with the professional organization FIG (Federation International de Geometres). Working Group on Satellite Navigation Systems has organized several planned actions in 2000, 2001 and in 2002. The actions considerably contribute to exchange of information and to initiate the broad application of satellite positioning systems to land, marine and air navigation in CEI countries.

 

Cooperation with EGS results in the yearly organization of a symposium on the geodetic and geodynamic programs carried out in the frame of the international cooperation of CEI countries.

 

CEI Section C "Geodesy" and the Subcommission "Geodetic and Geodynamic Programs of the Central European Initiative (CEI)" declares to supply and release to the aims of the Commission XIV the following results:

·    results of the GPS campaigns of CEGRN carried out in the frame of CERGOP;

·    velocity vectors of about 60 sites in Central Europe computed by the CERGOP Processing Centers from the CERGOP, EXTENDED SAGET, EUREF campaigns;

·    information on progress in determination of quasi-geoid in the Tatra Mountains;

·    information on local geodynamic projects realized in Central Europe within the CEI bilateral and multilateral cooperation;

·    information on work progress concerning the 7 CERGOP Study Subgroups CSG.5/i of the CSG.5 "Geotectonic analysis of the region of Central Europe";

·    information on geotectonic monographs prepared by the CERGOP Study Subgroups CSG.5/i "Geotectonic analysis of the region of Central Europe";

·    information on progress in the realisation of the post-UNIGRACE actions.

 

CEI has developed a web page at the following address: http://www.gik.pw.edu.pl/igwiag/cei.html

 

Asia-Pacific Space Geodynamics program (APSG)

 

The APSG was endorsed by the IAG on its Boulder Meeting in 1995.  The early shape of APSG was formed in the First APSG Workshop, May 13-17, 1996 in Shanghai, China.  In Tahiti, French Polynesia, May 12-16, the Second APSG Workshop was held.  The Third APSG Workshop was held in Tsukuba, Japan, on Oct. 20, 1999, along with the International GPS Symposium. The Fourth APSG Workshop came back to Shanghai on May 14-19, 2001.

 

On the 2001 Shanghai Workshop, the Scientific Working Group N. 4, Gravimetry in the Asia-Pacific Region, was established. Numbers 1-to-3 are Geodynamics and Natural Hazards of the Indo-Eurasian Collision, Geodynamics and Natural Hazards of the Western Pacific Region and Impact of Sea Level variations on the Asia-Pacific Region.

 

The Management Board consists of representatives from 9 Countries, namely: Australia, China, France, Germany, Indonesia, Japan, South Korea, Russia and USA.

 

Beginning from 1997, APSG VLBI Experiments including 6 VLBI stations in the Asia-Pacific region were organized, to support the yearly campaign of APRGP (Asia-Pacific Regional Geodetic Project).  Scientific results of the Scientific Working groups mentioned above have been reported and exchanged on the APSG Workshops and relevant meetings.

 

The Gravimetry Group has a plan to perform Precise Gravity Observation in East Asia with Super Conducting and Absolute Gravimeters (FG-5) in China, Japan and Indonesia, in the 2003-2005 time frame.

 

The Institute of Astronomy, RAS, and the Irkutsk State Technical University organized an APSG International Seminar on Aug. 5-10, 2002, at Irkutsk, Russia. At this seminar, by recognizing the very broad area of GPS applications with mm level of accuracy, a resolution on establishing a Working Group on the Methods of GPS Measurements and Data Processing was accepted. An International Seminar on this topic will be held in early June 2003, in Bishkek, Kyrgyzstan, to exchange and discuss the optimal allocation of observing networks, construction of geodetic monuments, analyses of GPS data, comparison of different software, parameters and processing methods. The seminar is timely and important for precise GPS measurements.

 

During the IAG/IUGG Meeting in Sapporo, a short APSG meeting will be held to discuss the results in recent years and plans for the future. The 5th APSG Workshop will be held in Hong Kong in 2004.

 

The Asia-Pacific region is been suffering for many serious natural hazards, APSG needs to be strengthened, and all colleagues interested in the program are warmly welcome to join.

 

The APSG Subcommission has a Web site at the following address: http://center.shao.ac.cn/APSG and can be contacted at the following e-mail: apsg@center.shao.ac.cn.

 

Central and South America

 

Central America

The activities in South America were mainly concerned with the establishment of RONMAC (Red de Observacion de Nivel del Mar para America Central) in Central America. The RONMAC project has been devised by the U.S. Government in direct response to the impact of Hurricane Mitch on four Central American countries: El Salvador, Guatemala, Honduras, and Nicaragua.  Participating Agencies are:

·    United States Agency for International Development (USAID), Funding Agency ;

·    Center for Operational Oceanographic Products and Services, National Oceanic and Atmospheric Administration (CO-OPS/NOAA), of the US Department of Commerce, as Administrating Agency ;

·    Unit for Sustainable Development and Environment of the Organization of American States (OAS/USDE), as Executing Agency;

·    Regional Committee for Water Resources (CRRH), as Regional Coordinating Agency;

·    National agencies in El Salvador, Guatemala, Honduras, and Nicaragua, as direct counterparts and beneficiaries of the RONMAC project.

 

The main objectives of this project are: a) support development and improvement of the geodetic framework of Central America; b) provide basic meteorological data to national and regional agencies; c) sea-level monitoring and establishment of long-term means sea level data series. At present, there are 11 operational RONMAC stations in Central America: Panama (2), Nicaragua (2), Honduras (1), El Salvador (3), Guatemala (2), Belize (1). There are also five satellite transmitting meteo-marine stations in Costa Rica to be upgraded as RONMAC type. LABCODAT has been established as a data quality control and spare parts center in Costa Rica.

 

Two training courses have been offered to Central American Meteorology and Geophysics technicians with the aim of providing them with the tools for appropriately operate and maintain the stations. Periodic refreshing courses will be conducted in the future.

 

RONMAC Web site (http://www.oas.org/ronmac/) where the user may download the data every three hours is available. Annual tide tables have been included in this site. It is expected this year the inclusion of a larger number of local predictions as well as periodic sea level and SST monthly control maps.

 

South America

In October 2002, an IAG international Symposium entitled "Recent Crustal Deformation in South America and Surrounding Areas", took place in Santiago de Chile. It was organized in 7 sessions, in which 41 oral and 25 poster presentations were given. Scientists from several countries attended. This event gave also the opportunity to south American geodesy practitioners and students to acquire new knowledge and experience from major experts in the field.

 

In parallel with the above-mentioned Symposium, a meeting dedicated to SIRGAS was held. The Geocentric Reference System for South America is intended to establish and maintain a reference network, together with defining a geocentric Datum. At this meeting, the current situation in each of the countries involved regarding the Reference Framework was presented. The main topic was the mission set for each country for the vertical control of data covering the continent.

 

The presence in Chile at Conception of the Transportable Integrated Geodetic Observatory (TIGO) is of major importance because of the increased interest that this generates for geodetic research on the continent. This is, in fact, the first and only fiducial geodetic station operating in South America.

 

Africa

 

The Hartebeesthoek Radio Astronomy Observatory (HartRAO) has in the past four years developed its Space Geodesy Programme to the extent that it has become one of five fiducial geodetic installations in the world. The three major space geodetic techniques; VLBI, SLR and GPS are supported. A DORIS system is also collocated with these three systems.

 

VLBI: 17 % of the 26 m radio telescope time has been allocated to geodetic VLBI, this leads to an average of 56, 24-hour experiments per year. Upgrade to MKV disk cartridge to replace the thin tape system has been budgeted for to keep abreast of latest developments.

 

SLR: MOBLAS6 achieved operational status in mid 2001, achieved superior performance level in mid 2002, and is constantly in the top ten SLR tracking sites as far as performance is concerned.

 

GPS: HartRAO joined the TIGA pilot project of the IGS as regional data enter and associate analysis center, in addition to being an IGS regional data center. Two GPS systems have been collocated with tide gauges, a further similar system is in progress. To support densification of the ITRF and the GPSVEL project, a total of seven permanent GPS systems have been installed, two of which are in other countries (Botswana and Zambia). A project has been established to equip each of the 14 Southern Africa Development Community (SADC) countries with at least one permanent GPS system. This will contribute greatly towards studies of the East African Rift system, evaluation of the African plate motion as consisting of the Nubian and Somalian plates, and will facilitate the conversion of the SADC region from obsolete datums (e.g. Clark 1880) to ITRF.

 

Several projects have been initiated to further the study of crustal dynamics. Analysis of data and development of reduction techniques is showing great promise to determine vertical crustal motion due to earth tide effects as determined by GPS. This will allow calibration of gravity changes due to earth tide effects at installations such as superconducting gravimeters, and the longer term component could be used to calibrate satellite (e.g. CHAMP) orbits.

 

HartRAO has collaborated with several institutions to develop space geodetic applications in the region, especially for geodynamics. Future plans include the conversion of MOBLAS6 to a Lunar Laser Ranging capability and the replacement of MOBLAS6 with an SLR2000 system.

 

Antarctica

 

The sub-commission promoted activities contributing to the study of crustal deformation processes in Antarctica and enhanced the co-operation with the GIANT (Geodetic Infrastructure of Antarctica) program of SCAR (Scientific Committee on Antarctic Research) WGGGI (Working Group on Geodesy and Geographic Information). The geodynamics studies were performed in close collaboration with the members of the SCAR Antarctic Neotectonics Group of Specialists (ANTEC), an interdisciplinary group empanelled to improve the understanding of the unique character of the neotectonics regime of the Antarctic plate.

 

The main activities focused on:

·    periodic measurement campaigns for crustal deformation monitoring continued in 2001, 2002 and 2003 as well as field campaigns by GPS networks and GPS permanent trackers. At continental level, observations were performed within the SCAR GPS Epoch (Dietrich et al., 2001) and, at regional level, within VLNDEF (Victoria Land Network for DEFormation control) and TAMDEF (Trans Antarctic Mountain DEFormation control). These latter ones were carried out by the Italian Geodesy Project (Capra et al., 2001) and by the NSF scientific Project (Hothem et al. 02).

·    Development of permanent geodetic observatories (GPS, DORIS, VLBI, tide gauges, absolute and cryogenic gravimetry) and the applications of collocation techniques. Integration of local and regional networks was encouraged, particularly by the data processing for international reference frame definition. AUSLIG (Australia) started the TIGA Project, a GPS Tide Gauge benchmark monitoring Pilot Project, regarding the whole Antarctica continent.

 

Publications

Capra A., Gandolfi S., Mancini F.,Sarti P., Vittuari L.(2001) VLNDEF project:  geodetic contribution   to geodynamics study of Victoria land, Antarctica. Proceedings of Gravity, Geoid and Geodynamics GG2000 IAG symposium, Banff, Alberta, Canada, July 2000 ,pp. 379-385.

 

Capra A., Gandolfi S., Mancini F.,Sarti P., Vittuari L . (2001) “VLNDEF project for crustal deformation control of northern Victoria land”.  AGS ’01 (Antarctic Geodesy Symposium), St.Petersburg, Luglio 2001, SCAR Report N.21, pp.8-10, January 2002.

 

Dietrich R., Dach R., Engelhardt G., Ihde J., Korth W., Kutterer H.J., Lindner K., Mayer M., Menge F., Miller H., Muller C., Niemeier W., Perlt J., Pohl M., Salbach H., Schenke H.W., Scohne T., Seeber G., Veit A., Volksen C. (2001) “ITRF coordinates and plate velocities from repeated GPS campaigns in Anatrctica – an analysis based on ndifferent individual solutions”. Journal of Geodesy,74:756-766.

 

Hothem L., Wilson T., Willis M. (2002) “TAMDEF. GPS measurements of bedrock crustal deformations. Reports of AGS 02 Symposium, Wellington, N.Z.

http://www.scar-ggi.org.au/geodesy/ags02/