The objectives of the Commission on Recent Crustal Movements(RCM) are:

- to promote the study of recent crustal movements,

- to promote and coordinate international cooperation in research of recent crustal movements, and

- to support to exchange information and to publish the results of international studies.

We decided the programs of activities for these objectives as:

- investigation of recent crustal movements by space techniques and conventional methods from the global viewpoint of geodynamics,

- improvement of methods for monitoring recent crustal movements of various scales as well as for data processing and analysis to develop modelling the dynamical process and to understand the mechanism of the movements,

- cooperation with CSTG and geophysical study groups in order to promote the above activitites, and

- cooperation with oceanic science research groups in order to understand the crustal movements under the ocean bottom.

National Representatives:

F.J.J. Brouwer (The Netherlands)

G.Carrera (Canada)

K.Feigl (France)

B. Ducarme (Belgium)

K.Heki (Japan)

I.Joo (Hungary)

J. Krynski (South Africa)

J.Mierlo (Germany)

J. B.Minster (USA)

E.R.Pujol (Spain)

A. Tealeb (Egypt)

Bureau:

President: T. Tanaka (Japan)

Vice-president: P.Vanicek (Canada)

H.G. Kahle (Switzerland)

Secretary: Wolfgang Augath (Germany)

Member of Bureau: P.Vyskocil (Czech)

Chair of Subcommissions:

African Subcommission: A. Tealeb (Egypt)

Central and South America Subcommission: Heinz G. Henneberg (Venezuela)

Geodetic and Geodynamic Programmes of the Central European Initiative Subcommission: H.J. Sledzinski (Poland)

Activity in 1995 – 1999

IAG Regional Symposium on Deformations and Crustal Movements Investigations Using Geodetic Techniques

The Symposium was held from August 31 to September 5, 1996 in Szekesfehervar Hungary. The main topics were 1. Crustal deformations, 2. Recent crustal movements, 3. Data processing and data analysis, 4. Applications of up-to-date geodetic and seismological techniques, and 5. Deformations of special engineering structures. The symposium was organized by Geodesy Department of College for Surveying and Land Management of the University of Forestry and Wood Sciences, lead by Prof. I.Joo. 47 people participated from 14 countries and presented papers. The proceedings were also published by the College, which include 34 papers. The following resolutions were agreed to issue by the participants.

Resolution 1: The Symposium on Deformations and Crustal Movements

Investigations:

Noting the Resolutions No.3 and No.4 of the IAG Subcommission for Europe(EUREF) accepted in its last symposium held in Ankara, Turkey, May 22-25, 1996. Recognizing the importance of establishment of the recommended fundamental height reference system to be used in recent crustal movement studies for the whole area of the European continent; and Recommends that all the CRCM specialists and collaborating institutions work in their respective countries for realizing this goal. Similar unified height system should be suitable for other continents.

Resolution 2: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing the importance of space technique, and especially GPS technology for RCM studies. Recommends to all specialists and cooperating institutions to exchange experiences in planning, organizing GPS measurements and analyzing data at the establishment of local or regional networks. Furthermore emphasizes the necessity to investigate the conditions under which GPS technology can be applied to crustal movement studies including heights. It is also useful to calculate combined leveling and GPS networks together.

Resolution 3: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing the importance of the present results of the latest investigations for deformations and recent crustal movement (RCM) studies; Points out that the uplifting- subsiding tendencies of several regions are not supported geodetically; thus Recommends to establish new investigation lines at typical areas and to repeat their measurements at regular intervals.

Resolution 4: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing the importance of geological, geophysical, tectonic information in connection with deformations and crustal movement investigations; Recommends the usage of these information.

Resolution 5: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing that in many cases the effects of technogen interventions and crustal movements appear jointly; Recommends to consider the above mentioned at analysing measurement data and to separate them from one another as it is possible.

Resolution 6: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing that deformations of smaller intensity (movements of smaller velocity) can be investigated by repeated measurements executed within longer periods; Recommends the analysis of the data of previous measurements and their usage if they are suitable in the present investigations.

Resolution 7: The Symposium on Deformations and Crustal Movements

Investigations:

Recognizing the importance of the activities of the CERCOP group establishing CEGRN as a frame network for local geodynamic studies in Central and Eastern Europe recommends to give this initiative support from the IAG Commission "Recent Crustal Movements".

Resolution 8: The Symposium on Deformations and Crustal Movements

Investigations:

Considers the symposium and other events related to it as successful and fruitful and a remarkable advance in RCM studies, and expresses their heartfelt thanks to the Local Organizing Committee chaired by Prof. Istvan Joo for this wonderful organization and hospitality offered to all of participants during their stay in Szekesfehervar.

Report of the Ninth International Symposium on Recent Crustal Movements (CRCM'98)

The Symposium was originally scheduled to be held in Luxor. But due to the outrageous terrorist attack in Luxor in November 1997, there was a long e-mail discussion between the Local Organizing Committee and the IAG to decide under which security conditions the IAG would confirm its sponsorship to the Sympopsium to be held in Egypt. By big efforts of A.Tealeb, the Chair of the local Organizing Committee, and Egyptian colleagues, and K.-P.Schwarz, the President of IAG, and the supports by IAG officers, members of Scientific Organizing Committee and Convenors the place of the Symposium was eventually moved to Cairo and the IAG confirmed its sponsorship. The Symposium was successfully held in Cairo as scheduled from November 14 to 19, 1998 under quiet and comfortable conditions.

Session topics were (1) Advances in geodetic techniques applied to crustal movements, (2) Modelling of crustal movements for geophysical parameter estimation, (3) Global-scale crustal movements and the stability of plate interiors, (4) Crustal movements around plate boundaries, (5) Quaternary crustal movements and comparison with geodetic motion, (6) Application of geodesy to natural hazards research, and (7) Local deformation monitoring and regional control.

The number of participants were 46 from Egypt and 48 from 15 other countries, and about 70 papers were actually presented. The folloowing Symposium Recommendations were approved by the participants;

1. The 9th International Symposium on Recent Crustal Movements (RCM'98) in Cairo, 14-19 Nov.1998 looks forward to a continued support of IAG to international cooperation for the study of crustal deformations.

2. Recognizing the significant contribution to crustal deformation studies of consistent global references provided by the ITRF and the IGS GPS orbits, the 9th International Symposium on Recent Crustal Movements thanks the International Earth Rotation Service (IERS) and the International GPS Service for geodynamics (IGS) for their excellent work, and requests all stations of regional and even local RCM (recent crustal movements) projects to be connected to the ITRF.

3. Recognizing the importance of measuring crustal deformations at the regional scale for understanding the geophysical phenomena involved in the collision of the Africa, Arabia and Eurasia plates, the 9th International Symposium on Recent Crustal Movements strongly encourages the establishment of multi-national projects between interested countries for this purpose.

4. The 9th International Symposium on Recent Crustal Movements welcomes the proposal of the Finnish Geodetic Institute and Finnish National Committee of IUGG to host in Finland an International symposium on crustal deformations. It is suggested that this symposium concentrates on a limited number of themes.

Report of CRCM Meetings

1. Date: September 5, 1997 , 13:15-14:15

Place: Rio Centro Room G1, Rio de Janeiro , Brasil

Attendants: Ruizhi Chen, Jean Dickey, Martine Feissel, Marco Fermi, Erich Gubler, Heinz G. Henneberg, Salah Mahmoud, Juhani Kakkuri, Fabio Radicioni, Kamal Sakr, Buskhasel Schaffin, B. Kolimershe Sledzinski, Habil Janusz Sledzinski, Torao Tanaka, Petr Vanicek

Items :T.Tanaka reported the IAG Regional Symposium held at Szekesfehervar in Hungary from Aug.31 to Sept.5, 1996.

J. Sledzinski, Chairman of Subcommission "Geodetic and Geodynamic Programs of the DEI(Central European Initiative)", reported the establishment of Subcommission and its activity following the printed report, "Geodetic and Geodynamic Programmes of the CEI(Central European Initiative)" & poster S3.2-07-P). Attendants mourned the death of Prof.Yu.Boulanger (Bureau member of CRCM), and agreed to send our condolatory compliments to Mrs Boulanger.

Reports of subcommission activities: S.Mahmoud and K.Sakr reported that Egyptian colleagues were preparating satisfactorily the CRCM'98 Symposium in Luxor, Egypt. Attendants agreed the change of the chairman of the Central and South America Subcommission from Prof. Milton de Azevedo Campos to Prof.Heinz Henneberg. J.Dickey and T.Tanaka introduced the idea and proposal about "Crustal Deformation Bureau", which is a kind of expansion of the previous ICRCM(International Center for Recent Crustal Movements)

Information of future Symposium/Congress;

1. Current Crustal Movementand Hazard Reduction in East Asia and South-east Asia, in Wuhan, PR. China, Nov.4-7, 1997.

2. CRCM'98 International Symposium in Luxor, Egypt, Nov.14-19, 1998.

3. IUGG/IAG General Assembly, in Birmingham UK, July 18-30, 1999.

The National Representative for the Netherlands is Dr. Ir. Frits J.J. Brouwer, Phone: +31-15-2691111, Fax: +31-15-2618962, e-mail: f.j.j.brouer@mdi.rws.minvenw.nl

2. Date: November 16, 1998

Place: Movenpik Hotel(Cairo)

Attendants: Makoto Murakami, Yoshimitsu Okada, Gero W. Michel, Istvan Joo, Johani Kakkuri, Salah M. Mahmoud, St.Stiros, A.Tealeb, A.Grachev, T.Grachev, T.Guseva, S.Baranova, S.Takemoto, P.Bridle, W.Augath, K.Sakr, M.Dubrov, M.T.Prilepin

Items: M.Feissel explained the recent policy of IAG that CRCM as well as holding the next CRCM International Symposium should be reviewed and the reforming and the future of CRCM be discussed at the IAG Executive Committee Meeting since crustal deformation (movements) has now become an important subject not only in IAG but also Geophysics and other field.

Participants discussed the future activity of CRCM and agreed that the continuation and extension of the present activity in CRCM and holding International Symposium are important and necessary for the future development in the RCM research, and these opinions were included in the Resolutions. As to the next CRCM Symposium, J.Kakkuri commented that the Finnish Geodetic Institute/Finnish National Committee of IUGG would be able to organize the next meeting of the CRCM if accepted.

3. Date: July 22, 1999, 18:00-19:00

Place: Room 111, Law Building, University of Birmingham, UK

Attendants: Suzanna Zerbini, M.Negusin, Alessandro Capra, J.Kakkuri, Kosuke Heki, Ashraf Mousa, Salah Mahmoud, Janusz Sledzinski, H.Tealeb, M.Kumar, Heinz Henneberg, Jaroslav Simek, Petr Holota, Clark R.Wilson, Jack A.Weightman, Martine Feissel, Torao Tanaka

Items: T.Tanaka reported briefly the activity of CRCM in the term from 1995 to 99 based on the draft of the IAG Travaux. H.Tealeb reported the Ninth International Symposium on Recent Crustal Movements (CRCM'98) held in Cairo, from November 14 to 19, 1998. Attendants thanked H.Tealeb and Egyptian colleagues for their efforts. H.Henneberg, Chairman of Central and South America Subcommission, H.Tealeb, Chairman of African Subcommission and J.Slezinski, Chairman of Subcommission "Geodetic and Geodynamic Programs of the DEI(Central European Initiative)" gave brief reports of their activities as summarized in the Appendixes [1],[2] and [3] in the following. T.Tanaka reported that the IAG has decided the change of Commission VII Recent Crustal Movement to"Crustal Deformation Commission" and S.Zerbini has been elected as the president of the Commission. According to the Symposium Recommendation approved at the CRCM'98 in Cairo, the CRCM Meeting asked J.Kakkuri about the possibility of holding the next Symposium in Finland. Since the next IAG Scientific Meeting is planned to be held in 2001, the next Symposium should be held in 2002. J.Kakkuri commented that it will be possible to prepare to hold the Symposium in 2002. S.Zerbini mentioned the future of the Crustal Deformation Commission in IAG should be discussed in the next two years, and that the topics and themes of the next symposium in Finland are also considered and fixed in this new Commission.

Regarding the activity of new Commission, H.Henneberg commented importance of role of North American members especially, not only for the Central and South American Subcommission but also for the RCM community, and asked to the new president to include the members from the United States and Canada in the New Commission and expect active cooperation. M.Feissel and T.Tanaka gave their sincere thanks to the participants for their kind contributions to CRCM.

Appendix [1] :

Report of Sub Commission Centro-South America of IAG Commission on Recent Crustal Movement (CRCM)

Introduction

The chairman of the subcommission designated in Boulder-Colorado 1995 during the last General Assembly of IUGG did not report any activities in this area, and was not present in the Scientific Assembly of IAG in Rio de Janeiro 1997. During this Assembly of IAG in Rio, the president of CRCM, Prof. Torao Tanaka, on occasion of the CRCM-Meeting proposed to reappoint the undersigned to organize again the subcommission as acting chairman, which was accepted by the present members.

Summary of the CRCM Sub-Commission Report presented at the 3. Venezuelan Congress on Geodesy, February 1998-cosponsered by IAG.

A. Transcription (partial) of the CRCM Meeting, Sept.5, 1998, Rio de Janeiro, Rio Centro Room G.1.

B. Introduction. Historical overview of the origen of the subcommission.

C. Geodynamics of the Caribbean:

a) Near field and middle range neotectonic Geodesy.

b) Continental and global neotectonic Geodesy.

c) General Aspects of recent crustal movements and earth surface changes - national and international cooperation.

D. Different Progress Reports of the Sub Commission.

E. Report of the Geotraverse of the Venezuelan Andes ( Saler-Linkwitz).

F. Large Scale Absolute Gravity Control in South America (The Jilag Campaigns).

G. Tectonic Movement Control of "El Tigre Fault in Argentina".

H. The Panama Report.

I. Report Costa Rica.

J. The CASA 93 program.

K. The Geodynamic Interaction of the mayor tectonic plates. Cocos, Nazca, South America, Caribbean.

L. Crustal Deformation along the Caribbean-South American plate Boundary derived from the CASA GPS project.

Remark:

a) The full report contains 17 pages with references in detail and is publishes in the proceedings of the congress 1998.

b) Independently, copies of the report were sent to: President of CRCM of IAG, President of IAG, Secretary of IAG.

1998 – 1999: Recent Developments, Contacts and Meeting Results.

1. 20 years of high precision gravimetric control along Bocomo Fault - Venezuelan Andes - Maracaibo 1998. (Hermann Drewes, Herbert Tremel, Klaus Stuber, Melvin Hoyer, Eugen Wildermann, Napoleon Hernandez, Angel Daal).

2. Crustal Deformations along the limit of the tectonic plates (Caribbean and South American ) in Venezuela determined by the CASA Project - Maracaibo 1998. (Hermann Drewes, Klaus Kaniuth, Klaus Stuber, Herbert Tremel, Napoleon Hernandez, Melvin Hoyer, Eugen Wildermann, Hans Gert Kahle, Christian Straub).

3. High precision Near Field Geodetic Measurements, 1999, in the Mucubaji - Mitisus and Bocono Networks in Venezuela (field campaigns in execution at present) (Antonio Gonzalez).

4. Space Geodetic Observations of Nazca - South America Convergence across the Central Andes. (Edmundo Novabuena, Lisa Leff ler-Griffin, Ailin Mao, Timothy Dixon, Seth Stein, I.Selwyn Sacks, Leonidas Ocola, Michael Ellis - Science 1998, Vol.279).

5. Report "Brazil".

1) nominated and accepted Prof.Paulo Cesar L.Segantine (Univ. of Sao Paulo) as National Delegate of the CRCM Sub Commission.

2) Prof.H.Erwes reports. Strong earth surface movements in the mountain areas near Novo Friburgo (North of Rio de Janeiro). These movements affected very strongly roads and their environments. He proposes the application of terrestrial photogrammetry to evaluate the damages and to look for solutions ( reconstruction).

6. Splitting of the "Humboldt-Glaciar" (Andes Venezolanos). First observations were realized 10 years ago by CEAPRIS(Comision Especial de prevencion de Riesgos Sismicos), the movement goes on - no measurements were realized (Seismic swarms were observed in no traditional areas).

7. Report Drewes 1999.

The 1999 CASA campaign along the Caribbean - South American plate Boundary was realized this year from March 3 to March 15. In Colombia a tide gage station was included in the measurements. (in Venezuela, tide gage stations were already included in the campaigns 1993 and 1996) (The complete paper will be presented in IUGG General Assembly 1999).

8. The Linkwitz Report - April 1999 (Extract of the personal contribution).

"Remarks for the continuation of the research work of the Andes Traverse (A.T.)". The research in the AT started 1988. Between 1983 - 1995 were realized several field campaigns and published. From the scientific point of view it is desirable to continue the geodetic research work toward the future. The following items are the contents of this "Free Air Laboratory". Measurement techniques, Cinematics in networks, Geoid changes, 3D Crustal Deformation (Bocono Fault), effectivity of inclination measurements in the fault area ( a clinometric system is already installed) application of photogrammetry to study cinematic point fields, height reference sistems in the context of levelling, GPS, trigonometric height transfer and special items for interdisciplinary research (Geodesy, Geology, Geophysics). This Report 1999 was finished the 5th of May 1999 in Pechina ? Spain, Heinz G. Henneberg, Acting Chairman, Sub-Commission Central and South America of CRCM-IAG. Email: emalco@larural.es

Appendix [2]

Report of the "Sub-Commission RCM in Africa"

The activities of the "Sub-Commission in Africa" during the period 1995 - 1999 were slow according to various problems related with the situation in Africa as the finance needed for the cooperations between the African countries and running the proposed programs. For that reason most of the African countries are working individually and only for local problems. There is no any motions for the bulk of the African countries to cooperate in regional problems such as the establishment of a unified geodetic reference for Africa.

Except of the above mentioned conditions, different activities exist such as;

-- Operating laser ranging stations in Egypt (Helwan) and South Africa,

-- Operating permanent GPS station in Egypt (Helwan), Kenya and South Africa,

-- Cooperation between different countries to study the geodynamics of the east Mediterranian region (USA, Turkey, Bulgaria, Greece, Egypt, ...)

-- Cooperation between different countries to study the geodynamics of the west Mediterranian region (Italy, France, Aspain, Algeria, Morocco, ....)

-- The establishment and GPS measurement of different regional geodetic networks to study the geodynamics of different i,portant areas in Egypt (Sinai, greater Cairo, Aswan),

-- Setting programs for the geodynamic studies of Red Sea using GPS technique,

-- Operating earth tide gravimeter in Egypt (Helwan),

-- The establishment and measurement of geodetic networks to study local problems (El- Asnam in Algeria, Aswan in Egypt, ...)

-- Holding the 9th International Symposium on RCM in Cairo, Egypt from 14-19 November 1998.

Other Programs were prepared in order to study the geodynamics of;

-- The east African rift system,

-- The Red Sea, which of course need intensive cooperations between the interested African countries and international support.

Appendix [3]

Progressive Report of the Subcommission "Geodetic and Geodynamic Programmes of the Central European Initiative (CEI)"

1. Introduction

In February 1996 the present subcommission was founded to initiate the cooperation links between CEI WGST Section C and IAG. Prof.Dr.J.Slezinski(Poland) was elected as the Chairman.

The general charter duties are:

(1) coordination and/or integration of the international geodetic and geodynamic programmes supported by IAG and CEI,

(2) creation of close links between running projects of IAG and those of CEI (e.g. CEL CERGOP -Central Europe Regional Geodynamics Project and IGS and EUREF, use of CEI permanent GPS stations within IGS and other programmes for maintenance of the ETRF and ITRF, etc.),

(3) initialisation of common geodetic and geodynamic projects for the region of Central Europe and Europe,

(4) fostering the cooperation among universities and research centres from Central Europe and Western countries in the filed of geodesy and geodynamics, promoting actions contributing to the development of innovative technologies and participation of CEI scientists in international IAG research programmes.

The members and respective areas of activities are :

Janusz Sledzinski(Poland) - Chairman of the Subcommission,

Jozsef Adam(Hungary) - links between national geodetic/geodynamic networks and EUREF,

Kazimierz Czarnecki(Poland) - cooperation between European universities (links between CEI and FIG or IAG similar bodies, the Subcommission scientific secretary,

Istvan Fejes(Hungary) - links between CERGOP and other geodynamic IAG projects,

Jan Hefty(Slovakia) - problems of coordinate systems, EUREF,ITRF and ETRF,

Iginio Marson(Italy) - interregional gravimetric connections, gravimetric projects of IAG/CEI,

Peter Pesec(Austria) - geodynamic use of CEI permanent GPS stations within IGS programmes,

Ewald Reinhart(Germany) - links/coordination and fostering a collaboration among projects of EU (e.g.ESA) and those of IAG and CEI,

Jerzy Rogowski(Poland) - geodynamic use of CEL permanent GPS stations within

IGS and other IAG programmes,

Jaroslav Simek(Czech Republic) - problems of homogeneity and time changes of precise levelling networks and vertical datum in Central Europe.

2. Geodynamic Programmme CERGOP and Its Relation to Other European Projects

The main objectives of the project are: to integrate the geodynamic research in the Central European region based on high accuracy space geodetic measurements, to investigate the most profound geotectonic features in the Central European region, the Teisseyre-Tornquist zone, the Carpathians, the Bohemian Massif, the Pannonian Basin and the Alpine-Adria region as well as to provide a stable Central European GPS Reference Network(CEGRN) for sub-regional, local or across the borders investigations and deformation studies. 11 countries joined the Project in 1994.

Since 1994 five epoch monitoring campaigns of satellite GPS (Global Positioning System) have been carried out on this network in 1994, 1995, 1996, 1997 and 1999. The CERGOP Data Centre was established in 1994 and is hosted by the Observatory Lustbuhel, Graz, Austria. In a later stage of the project the number of processing centers increased to 8. A major development of the project was the establishment of CERGOR Study Groups(CSGs). The groups were formed by the collaboration of scientists from two or more member countries to carry out research in a particular field. The project participants have met regularly at the semi-annual CERGOP Working Conferences. The proceedings of these conferences were published in REPORTS ON GEODESY, by the Warsaw University of Technology. The scientific results were mainly presented at the bi-annual International Seminar on " GPS in Central Europe", organized by the FOMI Satellite Geodetic Observatory, Penc, in Hungary. The proceedings were also published in the REPORTS ON GEODESY series. Based on the results of CERGOP the velocity fields in the regions have been evaluated and the EUREF reference frame maintained.

First phase of the Project was concluded on 30 June 1998. The second phase of the project CERGOP-2 will include three new member countries; extension of the CEGRN will result in accepting in total more than 65 CERGOP(CEGRN) sites. There is a number of complementary investigations to CERGOP-2 which overlap our region and contribute to the understanding of the geophysical and structural complexity of Central Europe. The most significant overlapping projects are WEGENER, EUROPROBE, DOSE and UNIGRACE.

3. CEGRN and Levelling Networks: Status of Works on Levelling Networks and Vertical Datum in CEI Countries

The work has been mainly based on the activities of the study group CSG6,"CEGRN and Precise Height Determination". The main objective is to assign a couple of quantities, one geometrical and one physical -ellipsoidal height and geopotential number, respectively- to each CEGRN station and to investigate their possible time changes. The activities of the CSG6 are closely related to a number of projects developed under the umbrella of different scientific and governmental institutions.

At the initial stage the work of the CSG6 was mainly concentrated to the determination of geopotential numbers of CEGRN stations, namely a joint adjustment of primary levelling networks of CEI countries within the Unified European Levelling Network (UELN), and regional and local connection of CEGRN stations to UELN nodal points. The next stage is repeated CEGRN height determinations and interpretation of gravity field changes and geopotential model testing. The workshop of the CSG6 was held in Prague in April 25-26, 1996. Altogether 16 participants of 7 CEI countries took part in the workshop.

Up to now the necessary requirement for the unification of national vertical networks has been fulfilled in most CEI countries thanks to the activities of the BKG Frankfurt am Main (Aussenstelle Leipzig). At present the UELN is extended, in addition to "historical UELN countries" like Germany, Austria and Italy to the territories of Poland, Czech Republic, Slovak Republic, Hungary and Slovenia. Necessary levelling connections have been made between Croatia and Hungary, as well as between Slovakia, Hungary and Ukraine.

An important step towards unification of European vertical datums is the establishment of the European Vertical Network(EUVN). The realization stage of the project EUVN started in May 1997 by the EUVN GPS campaign with the participation of all CEI countries. The progress in unification and improvement of national vertical networks is summarized in national reports of individual countries presented every year at the EUREF symposia.

Most CEI/CERGOP countries make efforts towards the establishment of national geodynamical networks or at least local geodynamical networks in tectonically active areas.

A new project UNIHIP, directed to the merging and common analyses of national geodynamical networks of Hungary, Poland, Slovakia and the Czech Republic, was initiated in April 1999.

The joint effort of CEI countries resulted in formulation of a new project UNIGRACE which is directed to the homogenization and improvement of gravity reference frames of Central and East European countries. Successful is also the work on the unification of gravity networks of several CEI countries on the basis of long-term gravity measurements performed in mutual cooperation (e.g. Unified Gravity Network of Hungary, Slovakia and the Czech Republic).

4. Interregional Gravimetric Connections

The main core of the activities of the Subcommission in the field of interregional gravimetric connections and gravimetric projects has been the establishment and coordination of absolute gravity projects in Central Europe. Since an advanced technology in absolute gravimetry is now available in several academic and scientific institutions in Europe, a joint effort of members of IAG and of Subcommission has made it possible to coordinate and in some cases also to establish absolute gravity projects. The first project has seen the cooperation of absolute gravity teams of Finland, Germany, Austria, Italy and USA under a project coordinated by the Gravity Commission of IAG that was aimed at the establishment of absolute gravity sites in Croatia, Slovenia, Poland, Hungary, Lithuania, Latvia and Estonia. A second project, with the endorsement of the European Union, has been promoted and is presently carried out. The project, UNIGRACE (Unification of Gravity Systems in Central and Eastern Europe), is aimed at the establishment of absolute gravity in 17 sites in Germany (Wettzell and Rostock), Austria (Graz), Bulgaria(Sofia, Burgos), Czech Republic (Pecny), Finland (Metsahovi), Hungary (Penc), Italy (Trieste), Poland (Jozefoslaw, Wladyslawowo), Romania (Gilau, Constanta), Slovakia(Moda Pesky), Slovenia (Ljubliana, Zagreb) and Croatia(Dubrovnik). The gravity observations have been and will be made by five absolute meters from Austria, Finland, Germany, Italy/France and Poland in two observation campaigns in 1998 and 1999/2000.

Four review UNIGRACE conferences are planned in Germany, Poland, Bulgaria and Italy. The First UNIGRACE Working Conference was held in Frankfurt am Main (Germany) on 2-3 February 1998. The second was organised in Warsaw on 15-16 February 1999. 5. Geodynamic Use of CEI Permanent GPS Stations in IGS and Other IAG Programmes.

The great importance of permanent stations for practical geodetic works in every country and for research has been fully recognized in the research programmes of the Central European Initiative (CEI). The programme of the Section C recommends that each member country should establish and maintain at least one permanent station. The current situation indicates that at present (as on June 1999) there are about 40 permanent GPS stations operating in CEI countries: 15 permanent stations involved in the IGS international service and 25 stations in the maintenance of the EUREF. However it should be noted that all permanent stations are located on the territory of 8 CEI countries (Austria, Bulgaria, Czech Republic, Hungary, Italy, Poland, Slovakia, Ukraine). Eight CEI countries have not yet established any GPS permanent station (Albania, Belarus, Bosnia&Herzegovina, Croatia, FYROM-Macedonia, Romania, Slovenia). 6. Cooperation with Other Organisations

In the reporting period, links and coordination of the two projects within CEI * Central European Regional Geodynamics Project (CERGOP), and * Unification of Gravity Systems in Central Europe (UNIGRACE) were established and maintained to other international organisations and agencies. In order to coordinate the contacts to the EUREF Subcommission of IAG, a close cooperation was established with the Technical Working Group (TWG) and the Analysis Centres of EUREF.

Contacts are established and maintained to the International Gravity Commission (IGS) of IAG and especially to Working Group 2,"World Gravity Standards". It is intended to provide the results of the project for the establishment of a unified Gravity System for all of Europe.

The cooperation between the CEI WGST Section C "Geodesy" and the European Geophysical Society (EGS) is also worth mentioning.

7. International Conferences and Symposia

Several international symposia sponsored by the IAG and/or by other organisations in the field of geodesy and geodynamics were organised in CEI countries in the last years. The EUREF Subcommission continued to have its yearly symposia in CEI countries in Sofia, Bulgaria, 7th Symposium, 4-7 June 1997, and Prague, Czech Republic, 9th Symposium, 2-5 June 1999. International seminar series on "GPS in Central Europe" was also continued at Penc, Hungary. The Second Continental Workshop on the Geoid in Europe was held in Budapest, Hungary on 10-14 March 1998. An IAG Regional Symposium on recent crustal movements was held in Szekesfehervar, Hungary in August-September in 1996.

8. Publication of Proceedings

The proceedings of the conferences and symposia organised by CEIWGST Section C "Geodesy" are published in the series PERORTS ON GEODESY edited by the Institute of Geodesy and Geodetic Astronomy of the Warsaw Univerity of Technology. 25 volumes were published so far.

Appendix [4]

The dissoluition of ICRCM, Proposal of Crustal Deformation Bureau, and the Future of CRCM

The International Center on Recent Crustal Movements (ICRCM) was dissolved as an IAG organization on July 1, 1996. This was decided at the IAG Meeting in Boulder in July 1995. ICRCM has done great contributions to the extension and promotion of international cooperations of recent crustal movement studies under the leadership of Dr. P. Vyskocil, the Director of ICRCM. The Executive Committee of IAG established an ad-hoc planning committee to investigate the neccessity of a new structure such as "Crustal Deformation Bureau". Prof. W. Prescott was nominated as the Chair of the committee.

The next is the notice by Prof. Prescott:

Ad Hoc Planning Group

Establishment of a Crustal Deformation Bureau Chairman: W. Prescott (United States)

I. Function

It has been suggested that the time is ripe for the formation of a Crustal Deformation Bureau, which would play a role in the coordination of international crustal deformation activities similar to the role of the International Earth Rotation Service for earth rotation activities. It is the aim of this study group to evaluate this idea and make a recommendation as to whether the Association should move forward with plans for such a Bureau. In order to make this decision it is necessary to clearly define the activities and structure envisioned for such a Bureau. If a decision is made that such a Bureau is worthwhile, the discussion of activities and structure will serve as a useful starting point for the design of the Bureau.

II. Objectives

1. To consider the necessity and usefulness of the formation of a Crustal Deformation Bureau,

2. To make recommendations about the scope of activities of such a Bureau.

3. To make recommendations for how such a Bureau would be structured.

III. Membership

[To be determined]

Until then Review Board "Current Activities and Future Needs of the International Center on Recent Crustal Movement (ICRCM)" had considered the findings of the ICRCM Review Committee and current and future needs of the international geodetic and larger geophysical communities as follows: The desirable activities of such a center had evolved and increased since the formation of ICRCM. The ICRCM provided useful services, particularly in the area of education and linkages to developing countries; however, it was not meeting all the current scientific needs. With maturing space technologies (GPS and others) and the wealth of data available, the Review Board proposed the formation of a Crustal Deformation Bureau (CDB) in which the demands would be met by a network of centers. The structure proposed parallels that of the International Earth Rotation Service(IERS). Three coordinating centers are suggested based on three measurement types: classical terrestrial, space geodetic, and remote sensing techniques. Further, the data archiving would be based at regional centers. A Central Bureau would act as the main contact point; activities would be overseen by a Directing Board. Remote sensing techniques (such as Interferometric Synthetic Aperture Radar) are now under development. One would envisage this service being formed in a two step process with the first two coordinating centers being formed at the outset of the CDB and the third center based on Remote Sensing initiated later as the techniques evolve and mature. The scope of the Bureau was envisaged to encompass both marine and continental crustal deformation. As such, it would serve the following associations: IAG, IASPEI, IAVCEI, IAPSO, IAHS, and IAGA, IAG being the leading association. Linkages would be made with the ICL, IERS, and the International GPS Service. Appropriate representation would be sought for the Directing Board.

Central Bureau-------Directing Board
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Coordinating Centers.

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Ground-Based Space Geodesy                             Remote Sensing Measurements
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Regional centers         Regional centers                         Regional centers