Antarctic Neotectonics

John Manning¹ and Terry Wilson²

¹ Australian Surveying and Land Information Group - Canberra
² Department of Geological Sciences - Ohio State University

1. Introduction

Antarctica is characterised by a unique combination of active processes. Active crustal deformation (uplift, faulting) and active volcanism are widespread in West Antarctica and may occur beneath the ice sheet in East Antarctica where subglacial mountains and basins are present. Antarctica is also undergoing active glacial loading and unloading, which induces isostatic motions and applies unusual stresses to the crust. The association of glaciation with rifting and rift-flank uplift is unique. Active tectonic processes may influence the stability of the Antarctic ice sheets. The high-elevation Transantarctic Mountains may be characterised by unusually ancient landscapes preserved in the long-lived polar desert environment. The Antarctic continent appears to lack the intraplate seismicity that characterises all other continents and, coupled with abundant evidence suggesting rapid deformation, presents an unusual geodynamic paradox.

2. ANTEC Group of Specialists

At the SCAR XXV meeting in Concepcion, Chile, Prof. Dalziel, IUGS Delegate, presented to Delegates a joint recommendation from the Working Groups on Geology, on Solid-Earth Geophysics, and on Geodesy and Geographic Information, that SCAR should establish a new Group of Specialists on Antarctic Neotectonics (ANTEC). The presentation highlighted some unique aspects of the Antarctic continent such as:

· It lies at the centre of a lithospheric plate that, unlike any other, is almost entirely surrounded by spreading ridges and, furthermore, has been essentially in a polar position for the last 100 million years;

· It appears to lack the intra-plate seismicity that characterises all other continents;

· It includes at least one intra-plate rift system, stretching from the Ross Sea to the Weddell Sea, that has unique characteristics including possible implications for the stability of the West Antarctic Ice Sheet.; and

· It is covered by the only extant continent-scale ice sheet, which applies unusual stresses to the crust.

The presentation emphasised the current development of new technologies that are making possible new studies in geodynamics and neotectonics. These provide an opportunity for earth scientists and allow Antarctica to be placed more precisely in the global framework. (SCAR Bulletin 133, April 1999)

Delegates agreed that a Group of Specialists on Antarctic Neotectonics (ANTEC) should be established with the following Terms of Reference:

The preparation of an Implementation Plan that should include, but not be limited to:

· Identification and coordination of additional sites where permanent geodetic control is essential for geodynamic research purposes,

· Identification and coordination of additional sites where permanent seismic stations should be installed for addressing the structure beneath Antarctica (lithosphere and asthenosphere).

· Encouraging and coordinating installation of instruments at such permanent sites, and in regional networks of instruments (GPS, gravity, seismic) for focused studies,

· Facilitating the sharing of instrumentation,

· Ensuring that protocols for data collection, archiving and distribution best serve the needs of the research community.

The Promotion of scientific research opportunities and directions by:

· Holding workshops and symposia to identify promising research directions in neotectonics and geodynamics of Antarctica.

· Encouraging studies in relevant geoscience areas, such as stress determinations, micro faulting, geochronology (taking advantage of developments in high precision traditional techniques and the emerging cosmogenic radionuclide methods), landscape evolution, and petrology.

ANTEC membership was subsequently approved by the SCAR Executive Committee (see previous page).

3. Science Objectives

The goal of the ANTEC program is to improve understanding of the unique character of the neotectonic regime of the Antarctic plate. Within that goal, specific objectives and the questions which they should address were identified at the inaugural meeting of the group in March 1999 as:

Differentiate between glacial and tectonic kinematic signals

· Which tectonic features are active?

· What rebound patterns are resulting from mass load changes?

· Are glacio-tectonic features active (or were they active in the Neogene) ?

Map the deep structure of the Antarctic lithosphere and asthenosphere

· How are the mechanical properties and properties of the lithosphere distributed?

· Are there mantle plume signatures?

Document seismo-tectonic features of the Antarctic plate

· Is the continent truly aseismic?

· Do patterns of seismicity / aseismicity relate to ice-mass loads?

· What kinematics and dynamics are indicated by the seismicity?

Better understand nature of coupling between tectonics, climate and erosion

· What is the distribution of active faulting?

· Age and evolution of landscape patterns?

· Rates of uplift and denudation?

· Relation of uplift to active and post-glacial faulting?

· Active rift basins?

· Links between active volcanism, postulated mantle plumes, uplift and tectonism?

4. Strategies for Antarctic Neotectonic Research

ANTEC is developing strategies to take advantages of recent advances in technology and increasing availability of continent-wide space imagery and geophysical data. To progress its objectives four principal areas of research have been identified with a further need for technical development and general co-ordination. The principal research areas are:

Geodesy and Remote Sensing (Contacts: Bell, Capra, Dietrich, Manning)

Responsibilities include:

· Co-ordination of data collection and exchange for existing permanent GPS stations and for regional GPS epoch based networks.

· Integration of predicted horizontal and vertical motions due to tectonics and glacial rebound in planning for new permanent stations.

· In collaboration with other groups plan location of new stations inland from coastal regions taking into account crustal block boundaries and model predictions from rebound related uplift patterns

· Facilitation of the application of new satellite remote sensing data and techniques (gravity, laser altimetry, and radar interferometry) to Antarctic neotectonic research.

Seismology (Contacts: Ibanez, Morelli)

Responsibilities include:

Assessments and Compilations of:

· Current operational status of permanent seismic stations

· Availability of station data

· Locations and results of seismic studies of deep structure

· Known earthquakes within Antarctica

Formulate plans for:

· Improving availability of data from permanent seismic stations

· Systematic study of existing data archives to improve earthquake detection and develop cumulative data set

· Develop data base of focal mechanisms and stress data

· Workshop to establish science objectives of future seismological research and, based on these, identify optimum localities for new permanent seismic stations and target areas for regional temporary seismic instrument deployments.

Neotectonic Geology and Glacial Rebound (Contacts: Wilson, Bell, James)

Responsibilities include:

· Provide framework for planning optimum geodetic station configurations to isolate rebound and tectonic signals.

· Improve integration of relative sea level geodetic data into rebound modelling.

· Encourage collaboration between researchers investigating ice sheet mass balance, sea level change, and tectonics.

· Provide neotectonic framework for planning geodetic and seismologic station arrays and regional target areas for instrument deployment campaigns.

· Promote compilation and integration of results in the following areas:

· Structural geology/Tectonics: active and Neogene faulting; kinematic and dynamic interpretations of faults and fractures; integration of active fault studies from outcrop geology & geophysical data (offshore & onshore); Neogene and younger basin analysis.

· Volcanology: distribution of active and Neogene volcanism; petrologic evidence for mantle processes.

· Landscape evolution: tectonic geomorphology; timing and rates of uplift; landscape surface ages; raised beach levels.

An additional two general areas were also identified for specific action:

Technological Development (Contacts : Wilson, Manning, Ibanez)

Responsibilities include:

· Address urgent need for solving problems related to power and communications for continuously operating geodetic and seismologic instruments

· Arrange Technological Development workshop to bring together all parties involved in developing improved power & communications for continuous GPS & seismic stations

General Co-ordination (Contact: Wilson)

In order to promote completion of research focused on neotectonic issues, ANTEC should:

· organise appropriate symposia at relevant national & international scientific meetings, and make sure these are widely advertised

· organise science planning workshop to encourage interdisciplinary and co-operative research

· organise thematic publications, possibly including continent wide map(s) (e.g., the ANTOSTRAT volumes published in AGU Antarctic Research Series)

· Consider how to foster 'Information clearing house' on relevant activities currently in progress

More detailed research plans will be developed for each area with the overall ANTEC activities made available on the ANTEC web site: <http://www.scar-ggi.org.au/geodesy/antec/antec.htm>

3. Geodesy and Remote Sensing

5.1 Geodesy

The Geodesy component will use existing data to build on the work of SCAR WG-GGI Geodetic Infrastructure program (GIANT) to provide best three dimensional movement vectors at existing permanent GPS, VLBI and DORIS base stations. This will provide a framework to extend observations for a more complete general coverage of the continent. It will facilitate a comparison of contemporary surface geodynamics with the long term geological record.

Existing sites

The results from existing continuous GPS sites are available from the International Earth Rotation Service (IERS), Figure 1, has been complied from International Terrestrial Reference Frame (ITRF) information contained in Sinex files available on the web site:

Meta data details of existing permanent stations already compiled by SCAR WG-GGI; information available on their web site:

http://www.scar-ggi.org.au/geodesy/perm_ob/sites.htm

Details of recent SCAR GPS epoch campaigns, co-ordinated by Germany, and resultant velocities are published in

"The Geodetic Antarctic Project GAP95 - German Contributions to the SCAR 95 Epoch Campaign" (Dietrich 96).

Results from these epoch surveys will be further collated with those from the permanent sites and made web accessible.

New Geodetic sites

The existing SCAR network of GPS permanent base stations is principally built on coastal rock sites at manned stations as a geodetic infrastructure for homogeneous spatial data. But there is a current technical limitation in providing power and arranging data retrieval at unmanned remote sites for continuous GPS observations required for accurately monitoring movement.

This technological limitation is being addressed by researchers such as Carol Raymond and, Andrea Donnellan as described at the NASA JPL web site. Coupled with satellite phone technology these developments should enable GPS data to be observed through the Antarctic winter and brought out from remote sites by satellite communication, while other data can be downloaded annually for retrospective processing.

When the technology permits new continuous operating GPS stations inland from coastal regions will be established taking into account logistics, continental coverage, crustal block boundaries and model predictions for rebound-related uplift patterns and the needs of a geodetic infrastructure for the spatial data community. This will provides a framework for more intense epoch based studies looking at specific problems such as the TAMDEF survey near McMurdo.

Whilst the technology is being developed sites the location of sites to best study the continental geodynamics and relationships with internal motion of blocks within Antarctic are being identified such as shown in figure 2. with the aim to better understand the contemporary geodynamics on Antarctic land mass.

5.2 Remote Sensing

There is an acute lack of gravity in Antarctica. Despite a recent focus on establishing absolute gravity sites to help to tie relative gravity networks together, there is still a need for both aerogravity to infill between ground sites and satellite gravity sensing for long wave length data. A primary task is to assemble an upgraded gravity data set suitable for integrating with new aerogravity and satellite borne gravity data.

There is need to collaborate closely with other research projects such as RAMP, BEDMAP, ADMAP, and ANTOSTRAT for neotectonic research and to arrange for ground truthing and calibration of satellite imagery and remotely sensed geophysical data such as:

· SAR interferometry, SAR stereo, ERS Tandem Mission, RADARSAT Antarctic Mapping Mission

· Laser altimetry from 'ICESAT'

· Gravity data from CHAMP and GRACE missions

6. Conclusion

Antarctica presents a unique neotectonics system for research. The newly established ANTEC Group of Specialists will use new technologies and approaches to integrate studies in geodynamics and neotectonics to place Antarctica more precisely in a global framework.

7. References

Dietrich, R. (1996) "The Geodetic Antarctic Project GAP95 - German Contributions to the SCAR 95 Epoch Campaign", Deutsche Geodätische Kommission, München, Germany

Scientific Committee on Antarctic Research, (1998) SCAR Bulletin, No. 133, April 1999, Scott Polar Research Institute, Cambridge, UK.

8. Web sites

ANTEC -

http://www.scar-ggi.org.au/geodesy /antec/antec.htm

 

GIANT -

http://www.scar-ggi.org.au/geodesy/giant.htm

 

IERS - http://hpiers.obspm.fr/

 

ITRF - http://lareg.ensg.ign.fr/ITRF/

 

NASA JPL -

http://geodynamics.jpl.nasa.gov/antarctica/

 

TAMDEF -

http://www-bprc.mps.ohio-state.edu/GDG/tamdef.htm

Figure 1. ITRF velocities

GeoStar and GIS of Antarctica

Nengcheng Chen, Haiyang Han, Jianya Gong, Deren Li

Wuhan Technical University of Surveying and Mapping

Dongchen E

Chinese Antarctic Center of Surveying and Mapping.

Abstract
The impact of Antarctica, especially the Geographic Information System (GIS), on our future becomes more profound each day. It is urgent that we construct a GIS to enable the access, sharing and publishing of Antarctic data on the Internet. The rapid advance in network and component technology has been the most important characteristic of software development in recent years. This paper will present the features and functions of GeoStar software and the characteristics of Antarctica data. Moreover, we will introduce the Internet-based Geographic Information System of Antarctica, which includes facilities for data management, acquisition, spatial query, mapping and show etc, and which can access and manage multi- data source such as GeoFile, GeoDB, ARC/Info, MapInfo, DXF and MGE, and link with databases including Sybase, SQL server, Oracle, dBase, Access, FoxPro and Informix, which are able to access, share and publish Antarctica data on the Internet and can manage multi-scale maps.

Keywords

GIS, Antarctica, Internet GIS , GeoStar,DGI,DHM.

Introduction

This paper presents a new Geographic Information System-GeoStar software. The main advantages of the software compared to similar software are: (1) an object-orientated spatial data management platform which is highly efficient; (2) integration of the Vector, Image and DEM databases; (3)bcomponent GIS; (4) Internet GIS which provides the means to access, publish and share GIS data on the Internet. This paper explores how we can collect data ,construct the GIS database and publish distributive geographic information(DGI) of Antarctica on the Internet using GeoStar software.

The World Wide Web (WWW) is at present the most widespread electronic medium for the ordinary user. The enormous body of information on the Web is one of its great advantages. Another is the distributed nature of the information. However, GIF-format or JPEG-format images are the only forms of returned spatial data on WWW which makes manageing these images, eg. zooming in and out, pannning, online map production, modeling and analysis services, time-consuming work

Java, being robust, secure, easy to use, easy to understand, and automatically downloadable on a network,

is an excellent language basis for database applications. What is needed is a way for Java applications to talk to a variety of different databases. JDBC (Java Database Connectivity) is a Java API for executing SQL statements. It consists of a set of classes and interfaces written in the Java programming language. JDBC provides a standard API for tool/database developers and makes it possible to write database applications using a pure Java API.

Distributed Geographic Information of Antarctica

1. The actuality and importance of Antarctica data sharing.

The need to access, publish and share Antarctica data on the Internet increases each day with the rapid development of scientific research and groundwork, surveying and mapping in Antarctica. The present GIS data of the Antarctic topographic database is almost isolated: information and data is acquired, stored and analysed to meet the needs of an individual project or program, resulting in data redundancy and inefficiency of data collection and storage. The development of the GIS application is based on a concrete independent and close platform. Moreover, they use conflicting data languages, so are unable to share data. The increasing need for Antarctic information has furthered the advance of scientific research in Antarctica. In addition, people are demanding more and more information on the Internet, especially spatial information of Antarctica.

Compared with the traditional GIS, the Internet GIS has the following benefits:

Firstly, Internet technology transfers GIS, previously only for professional use, to the public information system. In other words, it make GIS available to everyone.

Secondly, accessing data on the Internet can reduce the cost of data distribution, improve the extent to which geographic data is shared and avoid repitition of data collection.

Thirdly, Internet-based GIS technology can construct a geographic information service network through the information highway.

2. The structure of Antarctica data.

An integrated Internet based GIS of Antarctica should contain the following sections:

Web home page data: Generally speaking this is the format of HTML. It includes hyper text, hyper media, hyper Link etc. Current Internet information only includes the above 3H information without the hyper map information. Basic collection, updating and publishing on Internet are performed but the question is how to organize them in a sensible and efficient way. According to the features of Antarctic web homepage data, we believethat web home page data should include the following four portions: scientific research, groundwork surveying and mapping, station information and online help. In recent years China has obtained more and more Antarctic surveying data with the development of GPS,GIS and RS technology; this includes the observation of crustal distortion of the whole Antarctica by means of GPS, the construction of the place names database by means of GIS, the acquisition of the satellite images of Antarctica by means of RS technology and research into sea level change by means of 3S technology. The above progenies provide the abundant data source for web home pages.

Vector data and attribute data: In 1994 the United States began their "Digital GeoSpatial Data Framework" scheme which is used to establish the GeoSpatial database. China will establish the large-scale GIS in the whole nation in order to avoid repitition of data collection, and will include the Digital Orthograph Map (DOM) ,Digital Elevation Model (DEM) and vector data. In this framework DOM is the dominating portion. DEM is produced together with DOM. The vector data include Geodesy reference points, transportation, water system, boundary, cadastral data and etc (Li, 1998). Scientific Committee for Antarctic Research (SCAR) [Working Group on Geodesy and Geographic Information (WG-GGI)] is responsible for organizing and managing international Antarctic scientific research on the following six research topics [or fundamental geographic datasets]:

1. Antarctic Coastline Data Project

2. Antarctic Hydrographic Data Project

3. Antarctic Ice Bed Elevation Project

4. Surface Elevation Project

5. Names Project

6. Features Project.

We argue that the vector data of Antarctica must include the following information.

1. Water system maps of the coastlines, lakes, rivers, unmelted Ice area and ice shelf data.

2. Island maps, showing boundaries, buildings etc. Island maps and water system maps constitute the framework of the Antarctic geographical region and perform an important role in terrain control; moreover, they are extremely important to Antarctic GIS. Most geographic analysis and applications are referenced to them.

3. Contour maps and elevation data which show the undulation of the topography, and are an important

data source of DEM. They are important for the study of the overlay and vicissitude of the Antarctic glacier.

4. Geodesy control points and place names data. The Vector data is stored in afile system and the attribute in a relationship database. The show component of GIS only shows the position and annotations of the points.

5. Metadata is the quantitative and qualitative description of Geographic spatial data (Kong, 1998; Lin, 1998b) and is the data to describe the contents, definition, spatial frame of reference, quality, management etc of spatial data. It is one of the key technologies of geographic spatial data and, primarily, includes information on mark, data quality, spatial reference, space-time, spatial data denotation, system, distribution, metadata reference etc. The metadata of this system includes the mapping region, collector, proprietor, the cover of the map, scale, accuracy, date of collection and updating, data structure and attribute, map projection and location of data etc.

6. Image data are acquired by the means of RS technology. China scientists analyse glacier flow and evolution, and iceberg movelent by monitoring changes in the ice sheet. Data sources have included MSS in 1970s, TM from1989 and radar imaging from1997.

3. The features of Antarctic geographic information

Distributed Geographic Information (DGI) includes geographic information such as map, image, data muster, analysis operation, reporter, etc which can be published in various ways on the Internet by means of network technology. Geographic information of Antarctica also has the distributive characteristics of perpendicular and horizontal distribution.

Perpendicular distribution: One region may have different thematic geographic information based on the same scale. eg, King George Island contains many layers of information: maps of coastline, hydrology, contours, place names, topography, plant distribution etc. (Figure 1). Moreover, different types of information may be collected and maintained by different departments in different ways. Coastline and contour maps etc may be collected by

surveyors; plant distribution map by biologists, place names map by means of GPS technology; hydrologic map using RS technology. Organizing the above data efficiently involves organising the Antarctic geographic data through horizontal distribution.

Horizontal distribution: A map of Antarctica showing surface elevation, lakes, ice shelf, station information etc. can serve as the home page (or main map) (Figure 2). Each island name can be used as the keyword of a hyperlink to each Antarctic station home page . The user can query any information from the Antarctica map to the Laser map and from the Laser map to Zhongshan station map by clicking on the hyper link, so performing a multi-scale query.

Different scales and different map projections : This is a feature of geographic information of Antarctica. Table 1 shows that Antarctic maps adopt different projections, and therefore are on different scales. It also indicates the heterogeneity of data source, as different maps use different data formats.

Table1. The comparison of maps

GeoStar Software:

1. The Characteristic of GeoStar.

GeoStar, which contains almost all of GIS functions, is an important scientific and technological research project in China during "8^th five years" and "9^th five years". GeoStar is an enterprise GIS software for managing large-scale spatial data. It can simultaneously manipulate graphics data, attribute data, image data and DEM. It can also be linked with various kinds of commercial DBMS, such as SQL Server, Sybase, Oracle, Informix, etc through ODBC. In addition, it can exchange data with currently popular GIS software and Chinese spatial data through its data-exchanging modules.

The core module of GeoStar is the platform of spatial data management, which is responsible for receiving, processing, querying, indexing and transferring spatial data. A set of API functions has been extracted and used by high level systems for data collection, spatial query, spatial analysis and other applications. A common spatial database can be shared by all modules.

The major characteristic of GeoStar is that it can integrate vector data, attribute data, image data and DEM. The integration is used mainly for professional large spatial databases, vector data, attribute data, image data and DEM and can be stored in different databases respectively and distributed through the integrated interface. The four kinds of data can be manipulated in cooperatively, such as zooming in and out, seamless roaming and performing spatial queries.

GIS of Antarctica:

1.Comparision of existing GIS of Antarctica on Internet

There are two traditional approaches to constructing client-side access to distributed spatial data search and access systems on the Internet: the Web client-to-server gateway approach and the Client-side plug-in approach. (Peng, 1997).

2.Model of GIS of Antarctica

The GIS of Antarctica, constructed as the distributed hyper map model (DHM) is distributed on the Internet, and constitutes the Web server, Client, multi-JDBC data acquisition server and multi-database server (Figure 3). This model address five fundamental features:

· Vector Graphic Data.

· Task separation.

· Computing distribution.

· Servers and Clients distribution.

· Inter-operability of mutli-data source

Using this model, the spatial data in clients are vector graphic data. All operations, for example zooming in and out, panning, online map production, modeling and analysis services are performed by the clients' machine, without the server . This new method undoubtedly reduces the burden on network transportation and the server.

This system includes many functions.

· It will be available on all platforms and operation systems equipped with the JAVA Virtual Machine. Users can start up this system with any WWW browser after which it has no relationship with the browser.

· This system can be operated expediently. Without installation, users can start this system when they know its IP.

· Users can analyze map features and descriptive attribute information for query, spatial analysis, thematic map production, distance analysis and tabular manipulation etc.

· This system provides a printing function. All kinds of results including mapping and tabular manipulation can be printed on the clients' side printer independent of the Server and the detailed printer type of the Client side.

· This system runs simultaneously in multi-languages.

· The system produces multi-scale graphics to be visually manipulated, users can acquire multi-data source on Internet and perform multi-media and explicatory functions.

· Security. Users can access data, but can not save information on the clients' side

Conclusion and future work

From figures 4, 5 and 6 we can come to the following conclusions:

· Internet based GIS of Antarctica is the best combination of GIS and Internet for access, sharing and publishing of Antarctic data online and can contribute to distributed computing and inter-operability of Geographic information.

· The distributed hyper map model is very effective for Internet based GIS of Antarctica.

· The characteristics are multi-distributed data sources, distributed component, distributed computing and inter-operability.

Internet based GIS of Antarctica is at the development stage and still has many problems to be solved, eg. the visualization of spatial information, software inter-operation, spatial analysis etc.

Acknowledgements

This Project is sponsored by Professor Deren Li, Professor Dongchen E, Professor Jianya Gong. They have given me much help during the design and implementation of this system. This project has been finished by all members of GIS Research Center of Wuhan Technical University of Surveying and Mapping and all members of Chinese of Antarctic Center of Surveying and Mapping. Here I express my gratitude to them.

3. Features and Functions of GIS of Antarctica.

This system includes many features.

· The tasks of Web server, Clients, multi-JDBC data acquisition server and multi-Database server are completely separate. The Web server manages Web services, providing classes that the system needs to run. The Multi-database server is responsible for data services, such as data computing and operating. The multi-JDBC data acquisition server provides the interface between the multi-database server and the clients' machine. Other tasks are performed by clients' machine, including show, query, mapping production and analysis.

· Computation is distributed on the Internet. Some is finished on the clients' machine, that which is relative to database management is performed on the multi- database server.

· The multi-database server and multi-JDBC data acquisition server are distributed on the Internet.

· This model provides the inter-operability of multi-data source. Only through the WWW, can users use multi spatial data sources, such as ArcInfo, MapInfo, MGE, DXF, GeoDB (Microsoft SQL server, Sybase) and GeoFile. The vendors of GIS data can use any GIS software. All GIS information can be published on the Internet.

References

Deren Li, Jianya Gong(1998), Design and Implementation of Digital GeoSpatial Data Framework in China. Journal of Wuhan Technical University of Surveying and mapping, Vol. 23. pp.293-303.

Jianya Gong, Xiangru Yuan (1998), Organization and Processing Approach to cross-Platform and Distributed Geographic Information. Journal of Wuhan Technical University of Surveying and mapping, Vol. 23. pp.364-369.

Xiangru Yuan, Jianya Gong (1997), Vector Graphic Seamless Link with Main Database Model for WWW GIS. Journal of Wuhan Technical University of Surveying and mapping, Vol. 3. pp.260-263.

SCAR [WG-GGI] Homepage:

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

Lin, H. & L. Zhang, (1996) A Web-Based GIS Catalog Browser for Distributed Spatial Data Retrieving. GeoInformatics'96 Wuhan, Oct 1996.

Lin, H. & L. Zhang, (1997). Pluggable Computing Strategy for Integration of GIS Environment Modeling. GeoInformatics'97 Taibei, May 1997.

Peng, Zh. & Nebert, D, (1997) An Internet - based Data Access System. GeoInformatics'97 Taibei, May 1997.

Robert Hewlett, (1997) Java & GIS, http://gis.athena.bcit.bc.ca/students/class96-97 /tec_paper.html.

Dia, Qi, Evans, Larry and Shank, Mike (1997). Internet interactive GIS and Public Empowerment. GIS 97 Conference Proceedings, February 17-20, Pages 555-560.

Web sites

GeoStar HomePage:

http://www.rcgis.wtusm.edu.cn/.

Chinese Antarctic Center:

http://202.114.113.240/Antarctica.

Figure 5. The map of Fields

Figure 6. The map of Great Wall Station

Polish Geodetic Activity in the 1998/99 Antarctic Summer Season

Marcin Sekowski

Institute of Geodesy and Cartography, Warsaw, Poland

Summary

The paper presents Polish activity in the field of geodesy in the Antarctic summer season 1998/99. The main task: participation in the SCAR EPOCH 99 GPS CAMPAIGN and several additional tasks, such as measurement of the local GPS network, measurements for producing a 1:50000 map of Admiralty Bay, precise measurements of the boundaries of the Site of Special Scientific Interest No8 located near Arctowski Station, supporting measurements for mapping the area of Turret Point on King George Island and neighboring Penguin Island, etc.

Introduction

Henryk Arctowski is Poland's full-year medium-sized Antarctic station, located in Admiralty Bay on King George Island, South Shetlands. The station was established in 1977, and since then has been maintained by The Department of Antarctic Biology of Polish Academy of Sciences. As a result of its establishment Poland became a signatory of the Antarctic Treaty and subsequently the station became the centre of continuous scientific activity. The principal role of the station is to serve as an ecological and earth sciences observatory.

Due to the co-operation between Department of Antarctic Biology and Institute of Geodesy and Cartography the author had the chance to join the summer party of the XXIII Polish Antarctic Expedition to Arctowski Station (December 1998 to March 1999).

The main goal of joining the expedition to include the main geodetic point of Arctowski into the GPS network of geodetic infrastructure of Antarctica developed in the GIANT program by participation in SCAR EPOCH 99 GPS CAMPAIGN.

The additional tasks were:

· Measurements of the local GPS network related to the main point.

· Measurements for producing the 1:50000 map of Admiralty Bay.

· Precise measurements of the boundaries of the Site of Special Scientific Interest No 8 located near Arctowski Station.

· Supporting measurements for making a plan of the station area including the existence of plants and the placement of various scientific equipment.

· Supporting measurements for mapping the area of Turret Point on King George Island and neighboring Penguin Island.

Figure 1. Geodetic pillar at Arctowski Station

SCAR EPOCH 99 GPS CAMPAIGN

When Arctowski Station was established a concrete geodetic pillar was also erected, and used for astronomical determination of the station co-ordinates (figure 1). The same point was used also ten years ago, in 1989, by the team making Doppler measurements at the station.

The pillar itself is of very strong construction, made of reinforced concrete and built on a rocky base about 200m away from the station. Considering that the area is free from obstructions, and the excellent condition of the pillar, it was obvious to use it for the GPS campaign. For SCAR EPOCH 99 purposes we named the point ARCT.

Before taking measurements the brass centering device was fixed on the pillar to ensure automatic centering of the GPS antenna with very high (less then 1 tenth of

millimeter) accuracy. All the equipment, i.e. GPS receiver, computer etc. were placed in a waterproof and windproof box near by the pillar. In addition, the power supply line was taken down.

The GPS equipment used, was Ashtech Z-12 GPS receiver with the remote option, which allowed the automatization of the data collection, and the geodetic L1/L2 antenna.

During the SCAR EPOCH 99 CAMPAIGN period, according to the schedule, between January and February 1999, continuous 24 hour GPS data collection with 15s interval was maintained. However the data collection started in advance at the beginning of the year and continued with no break until the second half of March.

With the exception of ARCT point, all local network point locations are the hills or rocks surrounding the station and the Admiralty Bay (Figure 2). These are Point Thomas (the rocky hill near by the station), Jeardine Peak, Tower Peak, Mount Wawel (the hill on the east side of the bay) and the rock on the Chabrier Island at the entrance to the bay.

The measurements were taken during 2-4 hour sessions, depending on the distance from the ARCT point, with the same 15s data collecting interval, so the estimated accuracy of obtained vectors, relative positions of the points, are on the level of a few millimeters

The equipment used was the set of two other double frequency Ashtech Z-12 receivers, the same type as the one operating on ARCT point.

The data collected were transferred afterwards to the SCAR EPOCH 99 CAMPAIGN data collecting center at the Institute for Planetary Geodesy in Dresden.

The single point position of ARCT point (62°09'41.4"S, 58°28'09.3"W) were calculated as an average value of the single point positions from over 3 months continuous data. The accuracy, in the sense of standard deviation, is about 3m, and the co-ordinates agree very well with the results obtained by the Doppler measurements.

Local GPS network.

Besides the permanent observations on ARCT point, measurements of the local network of 6 points were taken. All points were newly established with brass marks with a cross-shaped cut which were set into the rock. Furthermore two, similarly-marked points on Penguin Island were also set and measured.

The new precise network is expected to be used, among others, in the production of the existing 1:50000 map of Admiralty Bay.

Boundaries of SSSI No. 8

Along with the network measurements, the boundaries of the Site of Special Scientific Interest No 8 were precisely determined. SSSI No.8 is situated on the west side of Admiralty Bay close to and extending south from Arctowski Station. As the satellite technology and co-ordinate systems in geodesy make a standard it became necessary to determine the WGS84 co-ordinates for the points defining this protected area.

The boundaries determination have been determined according to the definition within the Management Plan for SSSINo8. The area there is delimited with four

points, the co-ordinates of which were determined in relation to ARCT point with decimeter accuracy. In addition, points were measured from three other characteristics in the area.

Additionally, rapid static and kinematic measurements were made to support making a plan of the station area . The purpose of this was to include into this plan the placement of various scientific, in most cases hydro-biological equipment, the extent of plants in the vicinity of the station as well as current placement of penguin rockeries and the nearest moraines.

The precise WGS84 co-ordinates of the lighthouse operating on the shore in front of Arctowski Station were also determined.

Turret Point and Penguin Island mapping

In support of the mapping of Turret Point in the middle-east part of King George Island and on Penguin Island, several GPS sessions were undertaken.

On Penguin Island two new points were established using brass marks with a cross-shaped cut. The points were placed at stable-look, huge rocks protruding from the soft ground of the inactive volcano which made the island, one of them in the middle of the volcano crater.

The measurements, completed using rough bathymetry around Turret Point and Penguin Island, are the basis for mapping activities in that area. Figure 3 presents the very preliminary measurements calculated at the station by Mr Rafal Pudelko.

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Polish Geodetic Antarctic Studies. A short historical outline

Janusz Sledzinski

00-661 Warsaw, Pl. Politechniki 1, Poland
Member of the First Polish Antarctic Expedition 1958/59

Active exploration of the Antarctic Continent by Polish scientists began in the late fifties and was focused mainly on different scientific investigations (geophysics, geodesy, biology, ecology etc.) carried out at two Polish Antarctic stations: Station A.B.Dobrowolski located in Bunger Oasis and Station H. Arctowski, Admiralty Bay, King George Island. This short historical outline remembers the main milestone works of Polish geodesists carried out at these two Antarctic stations.

The first Station in Bunger Oasis was taken over by Polish scientists from their Soviet colleagues on 23 January 1959 and was named Station A.B.Dobrowolski. The station is situated in a very specific Antarctic "oasis" where the nunatac stones appear above the ice, very strong winds blow, there is extremely high solar radiation, a very high temperature gradient, big differences between the daytime and night-time temperature; during the summer the day temperature is usually above zero and the humidity is very low.

During the 1958-59 Antarctic summer the first magnetic observations were made by Dr. Wojciech Krzeminski but probably the most valuable achievement of this first expedition to the A.B.Dobrowolski Station was the establishment of the gravimetric point in one of the pavilions of the Station and direct connection of this point to the main Polish gravimetric network. The gravimetric point was embedded in the stone ground and marked by special brass plate. For the measurement of the gravity difference the four-pendulum gravity-meter Askania Werke was used. We should remember that at the time this gravity-meter was commonly recognised as a very precise and sophisticated instrument. The gravity value determined by Z.Zabek and J.Sledzinski for the Antarctic Station (f = 66°16.3' S, l = 100°45.0' E, H = 35.4 m) was

g_Ant. = 982 424.4 mGal ± 0.4 mGal.

The next geodetic works in the A.B.Dobrowolski Station were carried out during the third Antarctic expedition organized by the Polish Academy of Sciences from 1978-79. The broad scientific program included the following works: establishment of a geodetic network in the Bunger Oasis, establishment of an astronomical reference point, magnetic observations, photogrammetric surveys aimed at developing maps of the vicinity of the Station to scales 1:500 and 1:5000 (Z. Battke - author of the maps). Also the gravimetric measurements were continued. The

Figure 1. A. B. Dobrowolski Station

Figure 2. Author in front of the gravimetric pavilion

established geodetic network consisted of 26 points and was measured by Dr. A. Pachuta and Dr. J. Cisak using Wild T2 theodolites and Zeiss EOK distance meters.

The established astronomical point (measured by Dr. J. Cisak) was determined by the Kawrajski method from pairs of stars at equal heights using a Wild T2 theodolite. The result of the determination was:

f = 66° 16' 34.4"S ± 1.6"

l = 100° 45' 00.7"E ± 0.3"

During the third expedition the Station was visited by Dr. Vincent Morgan, a scientist from Australia, who determined the coordinates of the astronomical point by satellite Doppler technique. His result gained from only three satellite passes was:

f = 66° 16' 30"E

l = 100° 45' 03"E

Magnetic works performed in 1979 by S. Mroczek focused on measurement of the magnetic deviation of navigation devices of two helicopters Mi-2 available at the Station and determination of the magnetic declination in the vicinity of the Station. The value of the declination was determined as

D_Dobrow. = - 89⁰ 36.4'

The time variation of the declination with respect to the measurements from 1958 were also determined.

The programme of gravimetric works included the gravity surveys in the region of the Station Dobrowolski and the gravimetric connection Station Dobrowolski - Mirnyj (Soviet Antarctic station). The gravimetric surveys in the vicinity of the Station were made by using the Canadian gravimeter Sharpe CG-2. For gravimetric connection of the Mirnyj station 4 flights, either by Soviet Mi-8 helicopter or Polish Mi-2 helicopter were carried out. As a result the new value of gravity for the point in Mirnyj was established; the gravity difference was determined as

dg_{Mirnyj-Dobrow.} = 34.37 mGal ± 0.05 mGal.

Hence, for the gravimetric point at Mirnyj:

f = 66° 33.1' S

l = 93° 09.5"E

H = 35.058 m

the following gravity value referenced to the pendulum point of Station Dobrowolski was achieved:

g_Mirnyj. = 982 390.0 mGal ± 0.4 mGal

This value agrees well with other determinations performed for Mirnyj by German, American and Soviet scientists. The gravimetric works were undertaken by Dr. A. Pachuta from the Institute of Geodesy and Geodetic Astronomy of the Warsaw University of Technology.

It should be mentioned that Polish geodesists have introduced some Polish names on maps developed during the 1978-79 expedition. We mention only the following: Zatoka Polskich Geodetów (Bay of Polish Geodesists), Beskid, Giewont (peaks of the mountains south Poland), Skala fok (Rock of Seals), Gniazdo Skuy (Nest of Skuy Birds), Czarna Skala (Black Rock), Wzgórze Kaminskiego (Kaminski Hill), Dolina Manczarskiego (Manczarski Valley), Góra Rózyckiego (Rózycki Peak).

Another Polish Antarctic station, Arctowski Station, established in Admiralty Bay, King George Island, South Shetland Islands began its operation on 26 February 1977 and since then has been working permanently (Figs 5, 6 and 7).

One of the first geodetic works was the establishment of the reference astronomic point. located near the lighthouse. However, the unfavourable weather conditions and very short nights during the 1977-78 summer expedition only allowed Dr J. Jasnorzewski to determine the astronomic coordinates with very low accuracy:

f = - 62° 09' 51" ±12"

l = 3^h 53^m 51^s ±0.8^s

This accuracy was well improved about ten years later by J.Cisak, M.Dobrzycka. They obtained:

f = - 62° 09' 39" ±2"

l = 301° 31' 32" ±2^s

They also determined the coordinates of the reference point at H. Arctowski Station by carrying out the Doppler observations in the frame of the Intercosmos Doppler Observation Campaign ICDOC. The coordinates of this point determined from 311 satellite passes related to the WGS72 system are:

f = - 62° 09' 41"

l = 301° 31' 49"

H = 30.60 m

The broad geodetic programme of the 1978-79 expedition and subsequent expeditions also included photogrammetric works aimed at preparation of maps of various parts of the vicinity of the Station H. Arctowski (Fig 8). We mention the following maps: the map of the Admiralty Bay Station H. Arctowski area at the scale 1:25000 (Dr. K. Furmanczyk, Dr. A. Marsz), maps at scales 1:5000 and 1:50000 of the vicinity of the Station of H. Arctowski (Dr. Z. Battke). map of a special protected area "Lions Rump" (Dr. J. Cisak and Dr. Z. Battke), map of the vicinity of the Spanish station at the Livingstone Island at the scale 1:5000 (Dr. P. Madejski). All the maps worked out by the geodesists were also used for the aims of biological studies (determination of the location of flora and fauna) as well as for geomorphologic and ecologic studies.

More than 1000 scientists have worked at the Station H. Arctowski since 1978. The scientists from other countries who have visited and worked at the station came from: Argentina; Brazil; Belgium; Canada; former Czechoslovakia; Germany; Monaco; New Zealand; Peru, former Soviet Union; Spain; United Kingdom and USA. Long-term projects were jointly undertaken in 1990-91 by Polish and Dutch scientists. Almost 20,000 tourists have visited the Station since 1976.

It should be stressed that permanent activity of the Antarctic Station H. Arctowski was lead successfully by the Institute of Ecology of the Polish Academy of Sciences, now is organized by the Department of Antarctic Biology of the PAS and personally by the Director of this Department Prof. S. Rakusa-Suszczewski. His personal engagement is gratefully acknowledged.

When speaking about Polish exploration in the Antarctic we must not forget the activities of two Polish geodesists who died ten and eighteen years ago.

Dr. Wojciech Krzeminski was the young boy scout who took part in the Warsaw uprising during WWII. Wounded he was than taken prisoner in Nazi Stalag IXB in Zeltchen near Dresden. From 1945-46 he was a soldier of the Polish

Army in Italy and in England, returning to Poland in 1947. From 1947-52 he was student of the Faculty of Geodesy and Cartography of the Warsaw University of Technology. He began to work in 1951 and his whole work was focused on magnetic surveys as well on selected problems of the geodetic metrology. He was a head of the First Polish Antarctic Expedition of 1958-59 and the Polish Antarctic Expedition 1978-79. He was very active on an international level in the framework of the scientific organizations of International Association of Geodesy of the International Union of Geodesy and Geophysics, SCAR, KAAPG and others. He died on 9 April 1981.

Dr. Jerzy Jasnorzewski graduated from Warsaw University of Technology, Faculty of Geodesy in 1932, began work at the Astronomical Observatory in Cracow and than at the Warsaw University of Technology. He specialised in geodetic astronomy, geodetic instruments and geodetic metrology. He took part in two polar expeditions to Spitsbergen and to Station H. Arctowski in Antarctica where he established reference astronomic stations. From 1959 he worked for 10 years as a Deputy Director of the International Bureau des Poids et Mesures in Sèvres. He died on 14 May 1989.

Bibliography

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J.Sledzinski, Z.Zabek. Sprawozdanie z nawiazania grawimetrycznego Warszawa-Antarktyda przeprowadzonego w ramach Polskiej Wyprawy Antarktycznej 1958/59 (Report on gravimetric connection Warsaw-Antarctic carried out in the frame of Polish Antarctic Expedition 1958/59). Biuletyn Informacyjny nr 2/28. Komitet Miedzynarodowej Wspólpracy Geofizycznej PAN, Warszawa, 1959 (in Polish).

Z.Zabek, J.Sledzinski. Wyprawa do Bialego Ladu Expedition to the White Continent). Przeglad Geodezyjny, nr 8/9, 1959 (in Polish).

Z.Zabek, J.Sledzinski. Liaison gravimétrique entre Varsovie et la Station A.B.Dobrowolski en Antarctique. Communication presentée à la douzième Assemblée Générale de l'Association de Géodésie de I'UGGI, Helsinki, 1960 (in French).

Z.Zabek, J.Sledzinski. Nawiazanie grawimetryczne Warszawa-Stacja im. A.B.Dobrowolskiego na Antarktydzie (Gravimetric connection Warsaw - Station A.B. Dobrowolski in Antarctic. Geodezja i Kartografia, t. IX, zesz. 3-4, 1960 (in Polish).

A. Pachuta. Nawiazanie grawimetryczne Mirnyj-Dobrowolski oraz zdjecie rozpoznawcze stacji Dobrowolskiego (The gravimetric connection Mirnyj-Station Dobrowolski and detailed surveys in the vicinity of the station Dobrowolski). Warsaw University of Technology, Institute of Geodesy and Geodetic Astronomy, Warsaw 1979. Unpublished Report (in Polish).

J.Cisak. Pomiar wspólrzednych astronomicznych punktu geodezyjnego w Oazie Bungera (Determination of astronomical coordinates of the geodetic station in Bunger Oasis). Przeglad Geodezyjny, No. 6, 1980 (in Polish).

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I Sympozjum. Prace geodezyjne w polskich wyprawach polarnych 1932-1982 (Proceedings of the First Symposium "Geodetic works in Polish Antarctic Polar Expeditions 1932-1982), Stowarzyszenie Geodetów Polskich, Glówna Komisja d/s Badañ Polarnych, Warszawa, 1982 (in Polish).

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J.Cisak, M.Dobrzycka, Z.Drozdzewski. Contribution of Henryk Arctowski Polish Polar Station to the INTERCOSMOS Doppler Campaign. Proceedings of the 6th International Symposium "Geodesy and Physics of the Earth", Potsdam, 22-27 August 1988.

Z.Batke, J.Cisak, M.Dobrzycka. Geodetic works carried out during the 12th Expedition at the Arctowski Station in Antarctic region. Prace IGiK, 36, 1989.

J.Cisak, S.Dabrowski. Polish geodetic and cartographic studies in the Arctic and Antarctic regions. Polish Polar Research, 11, 1990.

Zatoka Admiralicji. Antarktyka. Ekosystem strefy przybrzeznej morskiej Antarktyki (Admiralty Bay. Antarctic. Ecosystem of the coastal zone of Antarctic). Editor S.Rakus-Suszczewski. Oficyna Wydawnicza Instytutu Ekologii PAN, Dziekanów Lesny, 1992 (in Polish).