SOUTH AMERICAN GEOCENTRIC REFERENCE SYSTEM SIRGAS

SOUTH AMERICAN GEOCENTRIC REFERENCE SYSTEM SIRGAS NEWSLETTER # 4 December 1996

TABLE OF CONTENTS EDITORIAL COMPOSITION OF THE PROJECT COMMITTEE WORKING GROUP I: REFERENCE SYSTEM WORKING GROUP II: GEOCENTRIC DATUM SCIENTIFIC COUNCIL INFORMATION ON WORKING GROUPS I AND II MEETINGS HELD FROM AUGUST 05 TO 09 1996 IN SANTIAGO, CHILE MEETINGS AGENDA REPORT ON THE WORKING GROUP I REFERENCE SYSTEM MEETING REPORT ON THE WORKING GROUP II GEOCENTRIC DATUM MEETING LIST OF THE MEETINGS ATTENDANTS PHOTOGRAPH OF THE ATTENDANTS GROUP SIRGAS Project Newsletter # 4 Page 1

EDITORIAL I present to readers the fourth edition of the SIRGAS Project Newsletter. During 1996, important progress was achieved towards the establishment of a geocentric reference system for South America. From this point of view, we have to emphasize the activities carried by the working groups, specially the meetings held from August 05 to 09 in Santiago, Chile, simultaneously to the IV Congreso Internacional de Ciencias de La Tierra, event organized by the Instituto Geográfico Militar of that country. During those meetings, the preliminary results of the SIRGAS Reference Network processing were presented and the procedures of integrating the national geodetic networks into that reference network were discussed, besides other not less important matters. More details about those meetings can be found in this newsletter. The next meeting of the project was scheduled to the end of March 97, at Margarita Island, Venezuela, when the final results of the Reference Network, proposed by the Working Group I, will be analyzed and discussed by the committee in order to be officially adopted at that time. Therefore, considering the importance of the decisions that will be emanated, the participation of each country representative on the committee is highly necessary on that next meeting. I would like to take this opportunity to wish to readers and family a happy and successful new year. LUIZ PAULO SOUTO FORTES President of Committee COMPOSITION OF THE PROJECT The complete and updated composition of the committee, working groups and scientific council is presented bellow. COMMITTEE ENG. LUIZ PAULO SOUTO FORTES President IBGE/DEGED AV. BRASIL 15671 PARADA LUCAS RIO DE JANEIRO, RJ, BRAZIL, CEP 21241-051 FAX: 55-21-481 2747 e-mail: fortes @ deged.ibge.gov.br AGRIM. RUBEN RODRIGUEZ Representative of ARGENTINA LUIS M. CAMPOS 1521-6B 1426 BUENOS AIRES, ARGENTINA FAX: 54-1-781 8901 e-mail: rubenro @ arg.siscotel.com SIRGAS Project Newsletter # 4 Page 2

ENG. EZEQUIEL PALLEJA Substitute Representative of ARGENTINA JUNCAL 3699 PISO 10 (1425) BUENOS AIRES, ARGENTINA FAX: 54-1-383 2935 TTE. ENG. JOHNNY MOLLINEDO DEL VILLAR Representative of BOLIVIA INSTITUTO GEOGRAFICO MILITAR AVENIDA SAAVEDRA 2303 (ESTADO MAYOR) MIRAFLORES CASILLA No. 7641 LA PAZ, BOLIVIA FAX: 591-2-228329 ou 591-2-226912 SOF. 1RO. JAVIER GUZMAN GALLARDO Substitute Representative of BOLIVIA INSTITUTO GEOGRAFICO MILITAR AVENIDA SAAVEDRA 2303 (ESTADO MAYOR) MIRAFLORES CASILLA No. 7641 LA PAZ, BOLIVIA FAX: 591-2-228329 ou 591-2-226912 ENG. MAURO PEREIRA DE MELLO Representative of BRAZIL IBGE AV. FRANKLIN ROOSEVELT 194/GRUPO 207 CENTRO RIO DE JANEIRO, RJ, BRAZIL, CEP 20021-120 FAX: 55-21-262 7308 PROF. MILTON DE AZEVEDO CAMPOS Substitute Representative of BRAZIL UNIVERSIDADE FEDERAL DO PARANÁ - UFPR CAIXA POSTAL 19098, CURITIBA, PR, BRAZIL, CEP: 81531-970 FAX: 55-41-266 9222 e-mail: miltonac @ cce.ufpr.br MAYOR, OSCAR CIFUENTES ZAMBRANO Representative of CHILE NUEVA SANTA ISABEL 1640 SANTIAGO, CHILE FAX: 56-2-6988278 e-mail: igm @ reuna.cl MAYOR ENG. RODRIGO BARRIGA VARGAS Substitute Representative of CHILE NUEVA SANTA ISABEL 1640 SANTIAGO, CHILE FAX: 56-2-6988278 e-mail: igm @ reuna.cl ENG. ALBERTO GONZALEZ LOPEZ Representative of COLOMBIA IGAC CARRERA 30 NO. 48-51 OFIC 405 SANTAFÉ DE BOGOTÁ, DC, COLOMBIA FAX: 57-1-368 0991 MRS. ENG. SUSANA R. ARCINIEGAS Representative of ECUADOR ELDORADO, EDIFICIO DEL IGM QUITO, ECUADOR FAX: 593-2-569 097 e-mail: igm2 @ igm.mil.ec DR. CLAUDE BOUCHER Representative of FRENCH GUIANA INSTITUTE GEOGRAPHIQUE NATIONAL 136 BIS RUE DE GRENELLE 75700 PARIS, FRANCE FAX: 33-1-43 98 84 88 e-mail: boucher @ ign.fr SR. ABHAI KUMAR DATADIN Representative of GUYANA COMMISSIONER OF LANDS AND SURVEYS LANDS AND SURVEYS DEPARTMENT 22 UPPER HADFIELD STREET DURBAN BACKLANDS GEORGETOWN, GUYANA CAP. SEV. GEOG. JUAN CARLOS TORALES Representative of PARAGUAY DISERGEMIL ARTIGAS 920 ASUNCION, PARAGUAY FAX: 595-21-213 812 CAP.ENG. JUAN MUÑOZ CURTO Representative of PERU INSTITUTO GEOGRÁFICO NACIONAL AV. ARUMBURU 1198, SURQUILLO LIMA, PERU FAX: 51-14-753075 SIRGAS Project Newsletter # 4 Page 3

SR. R.H. WONG FONG SANG Correspondent of SURINAME CENTRAAL BUREAU LUCHTKAARTERING MAYSTRAAT 39 PARAMARIBO, SURINAME SR. HAYDEN NANTON Representative of TRINIDAD AND TOBAGO LAND AND SURVEYS DIVISION MINISTRY OF PLANNING AND DEVELOPMENT 18 ABERCROMBY STREET, P.O. BOX 1104 PORT OF SPAIN REPUBLIC OF TRINIDAD AND TOBAGO, W.I. FAX: 809-624 5982 PROF. ENG. AGRIM. ROBERTO PÉREZ RODINO Representive of URUGUAY INSTITUTO DE AGRIMENSURA FACULTAD DE INGENIERIA UNIVERSIDAD DE LA REPÚBLICA AV. J. HERRERA Y REISSIG 565, CASILLA DE CORREO 30 MONTEVIDEO, URUGUAY FAX: 598-2-715446 e-mail: rodino @ fing.edu.uy ENG. JOSE NAPOLEON HERNANDEZ Representative of VENEZUELA CARTOGRAFIA NACIONAL COORDINACIÓN GEODÉSICA EDIF CAMEJO - ESQUINA CAMEJO CSB PISO 2 - OFIC 216 CARACAS, VENEZUELA FAX: 58-2-5450374 e-mail: sagecan @ conicit.ve TTE. JOSE GONZALEZ BRICEÑO Substitute Representative of VENEZUELA DIGECAFA - MIN. DEFENSA FUERTE TIUNA - EL VALLE CARACAS, VENEZUELA FAX: 58-2-68 23405 DR. ENG. HERMANN DREWES Representative of IAG DGFJ, ABT. I MARSTALLPLATZ 8 D-80539 MUENCHEN, GERMANY FAX: 49-89-23031 240 e-mail: mailer @ dgfi.badw-muenchen.de TTE. CRNEL. FERNANDO MIGUEL GALBÁN Representative of PAIGH CABILDO 381 1426 BUENOS AIRES, ARGENTINA FAX: 54-1-776 1611 e-mail: pub @ gis.igm.gov.ar SR. JAMES A. SLATER Representative of DEFENSE MAPPING AGENCY MAIL STOP A-12 8613 LEE HIGHWAY FAIRFAX, VA 22031-2137, USA FAX: 1-703-285 9050 e-mail: slaterj @ pentagon-emh5.army.mil slaterj @ dma.gov WORKING GROUP I: REFERENCE SYSTEM DR. MELVIN JESUS HOYER ROMERO President CONSEJO NACIONAL DE CARTOGRAFIA UNIVERSIDAD DEL ZULIA APARTADO POSTAL 10311 MARACAIBO, VENEZUELA FAX: 58-61-512197 e-mail: mhoyer @ europa.ica.luz.ve MY. ENG.MIL. D. RICARDO ANTONIO TORCHETTI Principal Member CABILDO 381 1426 BUENOS AIRES, ARGENTINA FAX: 54-1-771 0498 SIRGAS Project Newsletter # 4 Page 4

ENG a. KATIA DUARTE PEREIRA Principal Member IBGE/DEGED AV. BRASIL 15671 PARADA LUCAS RIO DE JANEIRO, RJ, BRAZIL, CEP 21241-051 FAX: 55-21-481 2747 e-mail: katia @ deged.ibge.gov.br PROF. MILTON DE AZEVEDO CAMPOS Substitute Member UFPR CAIXA POSTAL 19098, CURITIBA, PR, BRAZIL, CEP: 81531-970 FAX: 55-41-266 9222 e-mail: miltonac @ cce.ufpr.br CAP. RODRIGO MATURANA NADAL Principal Member NUEVA SANTA ISABEL 1640 SANTIAGO, CHILE FAX: 56-2-6988278 e-mail: igm @ reuna.cl MRS. ENG. SUSANA R. ARCINIEGAS Principal Member ELDORADO, EDIFICIO DEL IGM QUITO, ECUADOR FAX: 593-2-569 097 e-mail: igm2 @ igm.mil.ec SR. HERVE FAGARD Principal Member INSTITUTE GEOGRAPHIQUE NATIONAL SGN BP 68 94160 SAINT MANDE, FRANCE FAX: 33-1-43 988450 e-mail: herve.fagard @ ign.fr DR. ENG. HERMANN DREWES Scientific Consultant DGFI, ABT. I MARSTALLPLATZ 8 D-80539 MUENCHEN, GERMANY FAX: 49-89-23031 240 e-mail: mailer @ dgfi.badw-muenchen.de PROF. DR. GUNTER SEEBER Scientific Consultant INSTITUT FÜR ERDMESSUNG UNIVERSITY OF HANNOVER SCHNEIDERBERG 50 D-30167 HANNOVER, GERMANY FAX: 49-511-762 4006 e-mail: seeber @ mbox.ife.uni-hannover.de DR. MUNEENDRA KUMAR Scientific Consultant DEFENSE MAPPING AGENCY/IOG 4600 SANGAMORE ROAD BETHESDA, MD 20816, USA FAX: 1-301-227 2582 e-mail: kumarm @ dma.gov WORKING GROUP II: GEOCENTRIC DATUM MAYOR RODRIGO BARRIGA VARGAS President NUEVA SANTA ISABEL 1640 SANTIAGO, CHILE FAX: 56-2-6988278 e-mail: igm @ reuna.cl SR. LORENZO A. CENTURION Vice-president DISERGEMIL ARTIGAS 920 ASUNCION, PARAGUAY FAX: 595-21-213 812 MY. ENG.MIL. HUGO RUBÉN BÉRTOLA Principal Member CABILDO 381 1426 BUENOS AIRES, ARGENTINA FAX: 54-1-776 1611 ENG. ROBERTO TEIXEIRA LUZ Principal Member IBGE/DEGED AV. BRASIL 15671 PARADA LUCAS RIO DE JANEIRO, RJ, BRAZIL, CEP 21241-051 FAX: 55-21-481 2747 e-mail: roberto @ deged.ibge.gov.br SIRGAS Project Newsletter # 4 Page 5

PROF. EDVALDO FONSECA JUNIOR Substitute Member UNIVERSIDADE DE SÃO PAULO EPUSP - PTR CAIXA POSTAL 61548 CEP 05424-970 CIDADE UNIVERSITÁRIA SÃO PAULO, BRAZIL FAX: 55-11-818 5716 e-mail: edvaldoj @ usp.br MRS. ENG. SUSANA R. ARCINIEGAS Principal Member ELDORADO, EDIFICIO DEL IGM QUITO, ECUADOR FAX: 593-2-569 097 e-mail: igm2 @ igm.mil.ec ENG. FABIÁN SANTAMARÍA Substitute Member ELDORADO, EDIFICIO DEL IGM QUITO, ECUADOR FAX: 593-2-569 097 SR. JOSE NAPOLEON HERNANDEZ Principal Member CARTOGRAFIA NACIONAL COORDINACIÓN GEODÉSICA EDIF CAMEJO - ESQUINA CAMEJO CSB PISO 2 - OFIC 216 CARACAS, VENEZUELA FAX: 58-2-5450374 e-mail: sagecan @ conicit.ve SCIENTIFIC COUNCIL TTE. JOSE GONZALEZ BRICEÑO Substitute Member DIGECAFA - MIN. DEFENSA FUERTE TIUNA - EL VALLE CARACAS, VENEZUELA FAX: 58-2-68 23405 SR. DON BEATTIE Scientific Consultant GEODETIC SURVEY OF CANADA 615 BOOTH ST. OTTAWA, ONTARIO K1A 0E9 CANADA FAX: 1-613-995 3215 e-mail: beattie @ geod.emr.ca DR. ENG. HERMANN DREWES Scientific Consultant DGFI, ABT. I MARSTALLPLATZ 8 D-80539 MUENCHEN, GERMANY FAX: 49-89-23031 240 e-mail: mailer @ dgfi.badw-muenchen.de DR. MUNEENDRA KUMAR Scientific Consultant DEFENSE MAPPING AGENCY/IOG 4600 SANGAMORE ROAD BETHESDA, MD 20816, USA FAX: 1-301-227 2582 e-mail: kumarm @ dma.gov Scientific consultants that advise the committee. PROF. DR. CAMIL GEMAEL RUA JESUÍNO LOPES, 305 SEMINÁRIO, CURITIBA, PR, BRAZIL CEP: 80310-610 DR. KNUD PODER GEODETIC DIVISION, KMS RENTEMESTERVEJ 8 DK - 2400 COPENHAGEN, NV DENMARK FAX: 45-35-87 5052 e-mail: kp @ kms.dk DR. IVAN MUELLER 4361 SHIRE CREEK COURT HILLIARD, OHIO, 43026 USA FAX: 1-614-292 2957 e-mail: mueller@mps.ohio-state.edu SIRGAS Project Newsletter # 4 Page 6

PROF. DR. HEINZ G. HENNEBERG ESCUELA DE GEODESIA, FACULTAD DE INGENIERIA UNIVERSIDAD DEL ZULIA APARTADO POSTAL 6 MARACAIBO, VENEZUELA FAX: 58-61-516225 58-61-517252 e-mail: henneber@europa.ica.luz.ve DR. GALO CARRERA GEOMETRIX GEODETIC AND HYDROGRAPHIC RESEARCH INC. 53 HAWTHORNE STREET DARTMOUTH, NOVA SCOTIA CANADA B2Y 2Y7 FAX: 1-902-466 3678 gcarrera@fox.nstn.ns.ca INFORMATION ON WORKING GROUPS I AND II MEETINGS HELD FROM AUGUST 05 TO 09 1996 IN SANTIAGO, CHILE MEETINGS AGENDA Monday, August 05: 1. Introduction 1.1 Welcome to the participants (Major Rodrigo Barriga, IGM Chile) 1.2 General status of the SIRGAS project and objectives of the meetings (Eng. Luiz Paulo Souto Fortes, President of the Committee) 2. Working Group I Meeting 2.1 Report of WG I President (Prof. Melvin Hoyer) 2.2 Report of Processing Centers: 2.2.1 DGFI/I 2.2.2 IBGE Tuesday, August 06 Working Group I Meeting (continuation) 1. Report of Processing Centers 1.1 1.2 Discussion about the processing, results (including comparison and validation) and interesting aspects Wednesday, August 07 Working Group II Meeting 1. Report of WG II President (Major Rodrigo Barriga) 2. Integration of National GPS networks available SIRGAS Project Newsletter # 4 Page 7

3. Contributions for future procedure (Dr. Herman Drewes and others) 3.1 How to integrate new densifications 3.2 Transformations parameters of old systems Thursday, August 08 WG I and WG II joint meeting 1. Summary of previous sessions 2. Conclusions and recommendations 3. IAG Rio 97 4. Publication of final results 5. Next activities Friday, August 09 Visit to Instituto Geográfico Militar of Chile REPORT ON THE WORKING GROUP I REFERENCE SYSTEM MEETING (prepared by the President, Prof. Melvin Hoyer) 1. Report of Working Group I President 1.1. Presented the list of active members of WG I and justified the absentees from the meeting 1.2. Presented a summary of the more important activities carried out by WG I 1.2.1. La Plata meeting 1.2.2. Organization of the GPS campaign 1.2.3. Organization of the processing 1.3. GPS campaign Reported the more important aspects of the observation campaign: Stations (principal and eccentrics) Countries Instrumentation Dates SIRGAS Project Newsletter # 4 Page 8

Number of participant institutions Summary of the stations observations (total or partially available data, problematic data, not available data) It was emphasized the success of the observation campaign. 1.4 Generalities about the processing work. Informed about the visit of the WG I president to DGFI/I in Munich, between July 1995 and January 1996, coinciding with the initial and medial stage of the processing in this institute. Mentioned the request of report about the processing to DGFI/I, and IBGE to be distributed and known before the meeting of Santiago (all the centers answered). It was informed about the reasons why the University of Hannover didn t take part in the campaign processing. It was recognized the work of DGFI/I at the previous stage (initial to the processing) of receiving, revising and correcting the data received from all countries, that allowed to prepare the RINEX data to be used by all processing centers. 2. Report of Processing Centers 2.1. DGFI/I 2.1.1. Exposition of Dr. Herman Drewes Dr. Drewes presented the exposition entitled The SIRGAS data and processing center at DGFI/I where he made some references to: Sending of GPS-SIRGAS data from each country to DGFI/I Statistic information of GPS-SIRGAS data (files, Gbyte, observations, etc.) Observations summary per station Strategies and participants in the data processing 2.1.2. Exposition of Eng. Klaus Kaniuth Eng. Kaniuth presented the exposition titled The SIRGAS network adjustment carried out at DGFI/I referring to: SIRGAS Project Newsletter # 4 Page 9

Available measurements and introductory aspects regarding the processing Stations where two or more receivers of different manufactures were used The scheme of preprocessing with Bernese software and strategies for GPS networks adjustment which include several campaigns or great data volume. Sub-network by instruments (Ashtech, Trimble, Leica and Rogue networks) Repeatability of baselines in length Troposphere estimation on collocation sites Adjustment consistence per day Problem of the reference benchmark materialization Processing summary, pendent actions and aspects to be discussed 2.2. IBGE 2.2.1. Exposition of Eng. Katia Duarte and Eng. Roberto Texeira 2.3. The IBGE representatives titled their exposition as Processing of SIRGAS reference network at IBGE referring to: Objectives Main characteristics of the software used (Geonap) Data analysis Processing aspects, executed tests, ephemerides precision analysis, examples of baseline results per day, transformations residuals, etc. Next actions and expectations 2.3.1. Introduction by Dr. Jim Slater Dr. Slater exposed an introduction to the SIRGAS measurements processing in clearing up the activities developed until that moment, when the processing in two work groups, one using Trimble/Geolab software and the other processing with GIPSYII software. Referred to the preliminary character of the results and the desire of definitely concluding the processing only with the GIPSYII software. SIRGAS Project Newsletter # 4 Page 10

2.3.2. Exposition of Eng. Timothy Siems 3. Discussion The exposition title was SIRGAS-: Report of processing I where the following was presented : Used software: GPSurvey 2.0 (Trimble) and Geolab 2.4 Processing parameters Processing and adjustment strategies Network adjustment Preliminary results Conclusions 2.3.3. Exposition of Eng. Kurt Krueger Eng. Krueger titled his exposition: SIRGAS-: Report of processing II referring to: Used software: GIPSY II Processing parameters Processing and adjustment strategies Preliminary results Immediate actions Comparisons to other solutions The most important aspects discussed were: 3.1. Introduction by the WG I President about the methodology for the discussion 3.2. Alternated interventions by the attendants regarding several topics: Need for complete stations descriptions Need for reference stations for the principal benchmarks Convenience to provide orthometric height to the stations Reference system for computation (ITRF93 or ITRF94) Stations to define the reference system Stations to be included in or excluded from the definitive computation SIRGAS Project Newsletter # 4 Page 11

3.3. Resolutions regarding the processing 3.3.1. Convenience to prepare a stations catalogue Regarding: To revise the descriptions consigned by each country. To distribute again the description proposal sent by WG I before the campaign. To reiterate the need for describing (when exist) and for measuring (if it was not done) the reference points of each station to assure the station permanence. To ask for each country to carry out the levelling of the SIRGAS stations in order to provide orthometric heights (including the reference points). 3.3.2. Need for having all necessary values to tie the eccentric measurements Regarding: Information of the Bogota station is missing. 3.3.3. Reference system for computation After an intense discussion, it was defined that each computing center will process the computations choosing a system and similarity transformations between that system and ITRF94 or ITRFC1 will be performed later. 3.3.4. Selection of stations to accomplish 3.3.3 It was agreed to use four stations: Santiago, Arequipa, Fortaleza and Kouru. Rio Grande can be included depending on its quality. The stations mentioned above will be weighted on the computation and not constrained. 3.3.5. Possible exclusion of some stations from the definitive computations It was agreed to include all measured stations except CHIQUITOS (Bolivia), due to evident problems with data. 3.3.6. Date to get the final results It was requested to the processing centers to send to WG I president, before November 30, 1996, the definitive list and results of the processing. SIRGAS Project Newsletter # 4 Page 12

After consulting WG I members and the scientific consultants, WG I president will propose the most reliable result to the SIRGAS project committee through its president in order to adopt a definitive result in a possible meeting on March 1997. 3.3.7. WG I president final comments Thanks to Working Group members and scientific consultants for their work Thanks to the Processing Centers for their contribution to the project. Recognition of the contribution and support of the meeting participants Advised about the preliminary character of the coordinates provided by some processing centers and asked for the attendants to not use them officially Call to the Processing Centers for making efforts that allow getting homogeneous computations in order to facilitate the adoption of a unique solution Highly thanks to IGM Chile for its hospitality and collaboration on organizing and realizing the WG I meeting SIRGAS Project Newsletter # 4 Page 13

REPORT ON THE WORKING GROUP II GEOCENTRIC DATUM MEETING (prepared by the President, May.Ing. Rodrigo Barriga) The SIRGAS Working Group II, during the IV Congreso Internacional de Ciencias de la Tierra, at room 10 of the Diego Portales Building s Event Center, in Santiago, Chile, from August 05 to 09, 1996, adopted the following Recommendations and Resolutions. RECOMMENDATIONS 1. To integrate the existing National Networks of each country, member of SIRGAS, individually, by each of them. 2. To integrate the new surveys carried out by each country into this new South American Continental Network. 3. To coordinate the need of each country regarding the coordinates Adjustment and Transformation. 4. To recommend to the countries to keep the final objective of integrating themselves to the same South American Continental Network. 5. To establish the coordination in processing Training and Help, for the following countries: Colombia, Paraguay, Uruguay and Venezuela. Without prejudice of it, the other countries will get the support of the Scientific Consultants. 6. To formally consult each country that has not attended to this SIRGAS meeting if it needs help. A letter regarding this subject will be sent. 7. To present the Recommendations for the integration of national geodetic networks into SIRGAS system before August 20 to the WG II president by the representative of Argentina. Sending of Recommendations and Consultations : August 20-30, 1996. Consultations and Comments : September 20, 1996. Analysis and Recommendations writing : October 15, 1996. Recommendations revision : November 01, 1996. 8. Recommendations that each country assumes the processing, on its own facilities or requesting help to some SIRGAS Processing Center. SIRGAS Project Newsletter # 4 Page 14

9. Recommendations that countries integrate their Classical Networks into the SIRGAS Continental Network according to the WG I specifications. RESOLUTIONS 1. To adopt the second option proposed by the SIRGAS-DGFI Processing Center, from Germany, for integration of the National Networks into the SIRGAS Network. (The first proposed option consists of tying Individual Networks into a unique network, with the transformation to Geocentric Datum using coincident stations with SIRGAS; and the second option, approved by the assembly, consists of tying the networks individually into the SIRGAS frame (per countries), directly referring to the Geodetic Datum). 2. For the integration of National Networks, it must be kept as an aim, in a median and short time, the connection to a unique network. 3. The transformation parameters to convert the old information to the new SIRGAS system must be established. 4. The rules and/or technical procedures to apply only one adjustment methodology, common to all countries, must be established. 5. It is recommended to all countries, members of SIRGAS, to coordinate with WG II, the requirements and needs of scientific and technological support necessary to perform the National Networks transformation and adjustment to the new SIRGAS Continental Network Coordinates System. SIRGAS Project Newsletter # 4 Page 15

LIST OF THE MEETINGS ATTENDANTS Eng. Luiz Paulo Souto Fortes Dr.. Melvin Jesus Hoyer Romero May.Ing. Rodrigo Barriga Vargas President of SIRGAS Committee, Brazil President of WG I, Venezuela President of WG II, Chile Ing. Ruben Rodriguez Representative of Argentina in the Committee Ing. Alberto Gonzalez Representative of Colombia in the Committee Prof. Agrim. Roberto Perez Rodino Representative of Uruguay in the Committee Mr. José Napoleón Hernandez Representative of Venezuela in the Committee and Principal Member of WG II Tte. Jose Gonzalez Briceño Dr. Herman Drewes Substitute Representative of Venezuela in the Committee and Substitute Member of WG II Representative of IAG in the Committee and Scientific Consultant of WG I and WG II, German Tte.Crnel. Fernando Miguel Galbán Representative of PAIGH in the Committee, Argentina Mr. James Slater Representative of in the Committee, USA My.Ing.Mil. Ricardo A. Torchetti Eng. Katia Duarte Pereira Cap.Ing. Rodrigo Maturana Nadal Mr. Herve Fagard Mr. Lorenzo A. Centurion Carmona Eng. Roberto Teixeira Luz Prof. Edvaldo Simões da Fonseca Jr. Dr. Muneendra Kumar Principal Member of WG I, Argentina Principal Member of WG I, Brazil Principal Member of WG I, Chile Principal Member of WG I, France Vice-President of WG II, Paraguay Principal Member of WG II, Brazil Substitute Member of WG II, Brazil Scientific Consultant of WG I and WG II, USA SIRGAS Project Newsletter # 4 Page 16

Mr. Donald Beattie Ing. Geom. Juan Carlos Montero Eng. Kurtis Krueger Eng. Timothy Siems Ing. Juan Francisco Moirano Lic. Claudio Brunini Ing. Nardo Lopez Mr. Ricardo Zambrana Gutierrez Mr. Gordon Garrard Ing. Jose Calvo Rojo Eng. Angus Jones Scientific Consultant of WG II, Canada Participant of IGM, Chile Participant of, USA Participant of, USA Observer of Argentina Observer of Argentina Observer of Argentina Observer of Bolivia Observer Canada Observer of Uruguay Observer of USA PHOTOGRAPH OF THE ATTENDANTS GROUP SIRGAS Project Newsletter # 4 Page 17