GPS and GIS-Based Data Collection and

Image Mapping in the Antarctic Peninsula 

by Richard D. Sanchez

Open-File Report 99-402

U.S. Department of the Interior

U.S. Geological Survey
GPS AND GIS-BASED DATA COLLECTION AND IMAGE MAPPING 

IN THE ANTARCTIC PENINSULA

Richard D. Sanchez

U.S. Geological Survey

521 National Center

Reston, Va. 20192

ABSTRACT

High-resolution satellite images combined with the rapidly evolving global positioning system 

(GPS) and geographic information system (GIS) technology may offer a quick and effective way 

to gather information in Antarctica. GPS- and GIS-based data collection systems are used in this 

project to determine their applicability for gathering ground truthing data in the Antarctic 

Peninsula. These baseline data will be used in a later study to examine changes in penguin 

habitats resulting in part from regional climate warming. The research application in this study 

yields important information on the usefulness and limits of data capture and high-resolution 

images for mapping in the Antarctic Peninsula. 

INTRODUCTION

In 1998, the National Science Foundation (NSF), Arlington, Va., joined the U.S. Geological 

Survey (USGS), Reston, Va., in a pilot study to determine the feasibility of using global 

positioning system (GPS) and geographic information system (GIS) based data capture systems 

combined with high-resolution images for accurately developing base line data near Palmer 

Station, Antarctic Peninsula. The ultimate goal of this project, in support of Dr. William R. 

Fraser, Montana State University, and NSF grant S-035, is to use these data to map the pattern 

and trend of Adθlie penguin habitats and their relationship to regional climate change. 

The fieldwork was carried out between January 6 and February 12, 1999, under the auspices of 

the NSF and as a cooperative project between the Mapping Applications Center of the USGS, 

and the Polar Oceans Research Group, Montana State University. 

Project Area and Source Data

The project area is located in the Antarctic Peninsula, the long extended finger of the Andes that 

reaches south into the Antarctic continent (fig. 1). The Antarctic Peninsula and adjoining islands 

are often grouped together as the Antarctandean Ridge (Arctowski, 1895). The geology of the 

peninsula and adjoining islands is dominated by igneous rocks of the Andean Granite-Gabbro 

intrusive suite, which is estimated to make up over 80 per cent of the total area (Harrington, 

1962). The peninsula is a jagged succession of snow peaks, black cliffs, nunataks, and glaciercloaked mountains. Along side the peninsula are a string of islands covered with rocky moraine 

___________________________

Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by 

the U.S. Government.
debris left behind by retreating glaciers. These islands, where beaches and cliffs offer snow-free 

nesting places, are home to millions of penguins, petrels, skuas, shags, and seals. Plants such as 

lichens and a few mosses, are able to inhabit the windswept, dry surface of the bare rock, which 

often displays a colorful (yellow, orange, and black) layer fertilized by bird droppings or guano. 

Mats of blue-green and green algae thrive in the vicinity of many of the bird colonies in part 

because of the nitrate- and phosphate-rich feces. As many an offshore passer-by will affirm, the 

air is tainted by the enormous amount of guano produced by penguin colonies. Cushions and 

turves of moss flourish on gravelly soils, especially where there is some shelter and moisture. 

There are only two flowering plants that are able to tolerate the peninsula's subzero weather, the 

low-matted Antarctic hairgrass Deschampsia antarctica and the compact, cushioned Antarctic 

pearlwort Colobanthus quitensis (Soper, 1994).

Figure 1. Global view of the Antarctic continent and peninsula map insert.

Palmer Station, the homeport of the project, is a year-round U.S. Antarctic base operated by the 

Antarctic Support Associates (ASA) under contract with the NSF. It is situated on a steelbulkheaded jetty and ice-free rocky spit of Anvers Island at 64°46' 27'' S., 64° 3' 6" W. Of all the 

U.S. Antarctic bases, Palmer Station is the most isolated and has few direct links with the outside 

world. Because there is no airport, the L.M. Gould, a slow research vessel operated under the 

U.S. Antarctic Research Program, delivers personnel and supplies. The distance from Palmer 

Station to the target islands of the study--Biscoe, Christine, Cormorant, Dream, Humble, 

Litchfield, and Torgersen--ranges from 1 to 14 km (fig. 2). The islands are reached only by boat 

(for example, zodiac boat). With few exceptions, permits are required under the Antarctic 

Conservation Act of 1978, Public Law 95-541, to work or visit the islands. The NSF, which 

administers the act, issued the necessary permits to conduct the fieldwork.

60°

55°

65° 

64° 66°

68°

Anvers

Island

Antarctic 

Peninsula
The project resource materials include low-altitude (457-m) aerial photographs collected by the 

British Antarctic Survey (BAS) in December 1998, National Technical Means (NTM) data 

approved by the Civilian Application Committee, and archived images from the U.S. Antarctic 

Resource Center (US-ARC). The primary field mapping components comprised an Ashtech Z12 dual-frequency GPS receiver and ERDAS Imagine 8.3.1 (including Arc-structured Vector 

Module), ArcView 3.1, PRISM, and GeoLink 5.7-K software installed on a ruggedized GRID 

notebook PC. Augmenting the RT-DGPS capability was the Rockwell Precise GPS Receiver 

(PLGR +96) with precise positioning service (PPS).

Figure 2. Satellite view of Anvers Island and project area.

METHODOLOGY

The flow chart in figure 3 shows the methodology applied in this investigation. Fieldwork was 

conducted during the austral summer, which provided the benefit of long daylight periods. 

Before going to the field, the study group did an inventory, collection, and evaluation of existing 

image and vector data; next they developed the data dictionary and transformed any useable data 

into a GIS-compatible format. Very little detailed, accurate geographic digital data and few 

published or unpublished maps exist for the seven target islands. Local map sketches of 

landings, caches, and colony locations were available, although not always complete. A USGS 

unpublished report on the construction of the permanent GPS continuous operation reference 

station at Palmer Station (PALM CORS) proved useful (Baumann, 1997).

Defining Features and Attribute Table

Although the Adθlie penguin habitat was of primary interest to this study, other landscape 

features were included. The multilevel land use and land cover classification of the USGS 

system (Anderson et al., 1976) was adapted for use by modifying several categories in creating 

the data dictionary (table 1). After the data dictionary was developed, the features and attributes 

were collected on the nearest target island (for example, Torgersen Island). This collection 

served as a test of the equipment and of the feature and attribute scheme. Once the template was 

Anvers Island

Cape Monaco

Biscoe Point Litchfield Island Cormorant Island

Humble Island

Christine Island Torgersen Island

0 5 10 km

Dream Island PALMER STATION
successfully tested, a field strategy was planned for collecting the data for each of the target 

islands. Planning data-logging routes in advance and defining function keys to capture feature 

attributes were important to the field strategy. Because of inclement weather conditions, a 

mission checklist was essential to achieving maximum time efficiency in the field. The penguin 

habitat feature layer was physically (horizontal and vertical coordinates) linked to attributes,

Figure 3. Flow process followed in this study.

including the type (Adθlie), status (active, extinct, original), colony number, date collected, size 

of each colony (square meters), and length of colony perimeter. 

GPS Ground Control Points and Static Survey

Identifying existing survey markers in the vicinity of Palmer Station (for example, PAL1, BC-4, 

and PALM) proved invaluable for periodically checking the accuracy of the GPS instruments. In 

these instrument accuracy checks, the Ashtech Z12 GPS rover-receiver radio link with the 

PALM CORS produced differentially corrected positions in real time with horizontal and vertical 

Convert format, 

projection, and datum; 

integrate spatial base 

data and images

 NTM, Landsat,

Acquire images:

 others

Gather data 

dictionary, 

user needs, 

maps, other 

source 

materials

Define GIS 

feature and 

attribute 

tables

preprocess

Scan and 

aerial

photographs

Collect GPS data to 

determine coordinates 

of photoidentifiable 

ground control points 

Perform preliminary 

single-image rectification

Perform feature 

collection and attribute 

entry with automatic GPS 

position coordinates

Edit and translate 

collected positions and 

attribute data to target 

GIS format

Perform quality control 

check of orthorectified 

images and GIS data sets

Conduct field verification 

and make any needed 

adjustments to GIS 

data sets

Postprocess static 

survey data with Prism 

Conduct 

photogrammetric 

processing---

triangulation, digital 

terrain model creation, 

and orthorectification 

Conduct followup field 

verification and modify 

data sets as needed

Change assessment

using archived images 

and base line data

Do accuracy assessment 

and documentation
accuracies at the millimeter-to-centimeter levels (see Appendix A). The Rockwell PLGR with 

PPS for point positions determined by autonomous methods produced horizontal and vertical 

accuracies in the submeter-to-meter range. 

To synchronize with the GPS-based data collection and to know the precise grid coordinate of 

any point on the islands, during January 1999 the field team located a minimum of 15 photoidentifiable and well-distributed RT-DGPS-collected ground control points for each island.

Table 1. Feature and attribute scheme

Level I Level II Level III Level IV

1 Habitat

2 Water

3 Surface

 Cover

11 colony

12 wallow

21 pond

22 snowbank

23 icepack

31 manmade

111 Adθlie

112 Gentoo

113 Chinstrap

121 Elephant seal

311 cache

312 flag line

313 landing site

314 snow transect

315 telemetry hut

 1111 active

 1112 original

 1113 extinct

In conjunction with the collection of these ground control points, static surveys were conducted 

for each target island to compute more accurate baselines and expand the limited area network of 

known stations. The static method was performed by occupying the highest (or near highest) 

point on each island for over an hour at 15-second intervals, using the Ashtech Z-12 roving unit. 

Simultaneous collection from the PALM CORS provided the RINEX files (range and carrier 

phase or binary measurements, predicted orbital coordinates or ephemeris data, and site 

information files) necessary for postprocessing. Unlike traditional tripod and tribrach 

combination setups of the antenna over the survey mark, a fixed height University Navstar 

Consortium (UNAVCO), see the Web site http:/www/unavco.ucar.edu) level mount was used in 

these static surveys. For geodetic coordinates and details about each survey marker erected, see 

Appendix C of this report. 

Image Processing

The ground control points collected for each island were identified within the available 1994 

scanned monoscopic aerial photographs and their horizontal positions correlated to 

corresponding geographic x and y coordinates. Then a least square regression analysis was 

applied to derive a first-order polynomial transformation of the images with less than a 1-pixel 
root-mean-square error. Following the geometric correction and nearest neighbor resampling at 

an output pixel size of 1 m by 1 m, I used a high pass box filter to enhance higher spatial 

frequency components of the image. Because most of the island topography contained steep 

relief, correction for terrain displacement with a digital terrain model (DTM) was deemed 

essential. However, owing to the late arrival (February 7, 1999) of the scanned stereoscopic 

BAS aerial photographs, plus software limitations, the DTM creation and orthorectification had 

to be processed in Reston, Va., using Softcopy Exploitation Tool Set (SOCET SET). 

Feature Collection and Attribute Entry 

The GPS receiver and GeoLink field mapping software were used primarily to collect colony 

features and attributes. The GPS and GeoLink interface allowed the laptop operator to log the 

footpath continuously. The positional data were transmitted from the GPS receiver to GeoLink 

by National Marine Electronics Association Interface Standard (NMEA 0183) protocol. The 

GeoLink export program translated the captured data from its native storage format to 

ArcSHAPE, the target GIS file format. Most of the area data were collected with the GPS 

receiver's external antenna magnetic-mounted to the field pack pole. Where there were no lineof-sight obstructions on the islands, the external antenna often required less than 5 seconds to 

obtain a fix on the satellites. Once the field team obtained the fix on the satellites, tracking 

began at 1-second intervals. Stops were made to identify and photograph features and collect 

attribute data. Information about feature attributes was keyed into the computer simultaneously 

as GPS-determined coordinates were automatically collected. The digital camera image allowed 

the team to cross-check the accuracy of the attribute data collected. It took less than 1 minute to 

enter attributes related to any colony feature. The descriptive data of features were collected by 

using predefined "hot keys" on the keyboard for different attributes (for example, type, status, 

and so on). Upon returning to Palmer Station and after inspecting the data collection results, I 

exported the data from GeoLink's native storage format (.DAT, .PLG .MDB and .IDB files) to 

the target GIS or ArcView interchange format (.SHP, .SHX, and .DBF files). During the export 

of the data to ArcSHAPE file format, they were cleaned by setting the GeoLink Translate Filters 

with an average cluster outlier tolerance of 10 to collapse small unwanted polygons and the weed 

filter of 10 m to remove unnecessary points. Setting the ArcView file extension to ERDAS 

Imagine Image support allowed the rectified images to be viewed as backdrops. Color and 

black-and-white ArcView graphic and tabular information was printed to supplement the 

verification process. 

Each spatial base overlay was individually viewed in contrasting colors over the image and 

systematically inspected for proper fit (fig. 4). The ability to switch overlays and toggle to adjust 

the ArcView color display provided a quick visual check of the registration revealed and any 

spatial inconsistencies. A random sampling was accomplished by systematically reviewing a 

vector display of the data set and image backdrop in subsections. Any feature that appeared to 

be either missing, altered, or unidentifiable in the image was marked for further inspection. Once 

compiled, the base line vector layers were stored on compact discs and on the hard disk of the 

Palmer Station science server.
FINDINGS 

Developing a field strategy is important to successful data collection. Also, ample time should be 

dedicated to designing the database. Field logs are recommended for recording anomalous

Figure 4. ArcView display of feature and attribute overlays with image backdrop.

situations, weather conditions, and any other factors that could affect data quality and data 

interpretation. I found that adhering to a checklist maximized time efficiency and prevented 

many human errors. When you are incorporating field data into a preexisting database, it is 

important to become familiar with its structure and match your data accordingly. This consists 

of the accurate translation of existing base data into one uniform file format and grid coordinate 

system. It also very important to periodically check the accuracy of the GPS-determined 

positions at stations with known high-accuracy coordinates. 

Common problems encountered ranged from an inability to read the laptop screen in bright 

sunlight to software and equipment disruption caused mainly by human oversights. Some of 

these disruptions include forgotten and faulty cables, weak batteries, incorrect data cable/port 

setup, overlooked conflicts in default settings, and software errors. An example of the software 

error occurred in the GeoLink Coordinate Converter. When the GeoLink was used, errors were 

introduced in the latitude conversion of geographic coordinates to Universal Transverse 

Mercator (UTM).

Accurate coordinate conversion of ground control points is essential in constructing
transformation matrices for image rectification. Errors of this kind occur when software 

manufacturers do not take into account shifts in transformations between datums, reference 

systems, or reference frames. Although it is not always possible, every phase of the vendor's 

software should be tested before going into the field, since accuracy claims given by 

manufacturers may not be met under all field conditions or circumstances.

Much of the value of well-registered digital images arises from the ease of integration with 

vector data. Unexpected pitfalls, however, can be associated with this integration. Vector data 

sets will not necessarily register exactly and uniformly with the registered image. For example, 

the Adθlie colony vector layers were free from most spatial inconsistencies, such as overshoots, 

undershoots, or area misclosures. However, these vector files did not always register precisely 

and uniformly with the geometrically corrected image. Because these Adθlie polygons were 

often collected over rough and steep terrain and the images were not corrected for terrain 

displacement, dimensionality differences and instance problems sometimes occur and have to be 

resolved. An orthophotorectification was not applied in the field because the appropriate 

software and the necessary data (stereo photographs, camera parameters, or DTM) were not 

available. A more rigorous correction for camera tilt and terrain displacement to the 1998 BAS 

color aerial photographs may resolve this problem. 

In GeoLink, the digital image used for general orientation to image registration is not precisely 

displayed. In applying GeoLink's Raster Module, one must convert the digital image file to 

Tagged Information File Format (TIFF). Any image exceeding 6 megabytes must be divided 

into tiles. Displaying tiled, geocoded images (DOQ's or multipoint field-registered images) can 

result in minor edge-matching problems; consequently, a positionally correct GPS-determined 

trace (for example, perimeter of the Adθlie penguin colony) during the data logging process will 

not always match the corresponding image at adjoining tiles. This mismatch between the GPS 

determined trace and corresponding background feature may also occur in a single nontiled 

registered image, especially when you are scrolling or zooming in to other parts of the image 

while logging (Sanchez and Hothem, 1998). This particular problem still remains unchanged, 

although in 1997 GeoLink indicated that it would upgrade the DOS Raster Module to NT/98 

operating systems (L. Nelson, oral commun. September 9, 1997). 

In selecting the color and resolution of digital images, I found that the high-resolution color

image, as compared to black-and-white, provides better contrast and separation, making it easier 

to correctly identify features from the surroundings. Most colony features in the integrated data 

set could be readily identified at Levels I and II of the feature and attribute scheme, and to some 

extent their specific type at Level III (see table 1). Clearly recognizable were colonies, wallows, 

ponds, snowbanks, and caches. Marked landing sites were difficult to recognize among the 

rocky shorelines. Note that the finer features of Levels III and IV, such as type and status of 

colony, may require field verification, regardless of high-resolution image capability. In general, 

the black-and-white digital image provides high detectability, but fine features are easier to 

distinguish, particularly in rocky areas, with the color digital image (Sanchez, 1996).

The static survey data were processed at Palmer Station, on board the L.M. Gould research 

vessel, and in Reston using Ashtech PRISM software. At Palmer Station, the collected static 

data from each of the newly established survey markers were downloaded from the rover 

receiver and processed with their corresponding PALM CORS' RINEX files. Some confusion 
over the vertical offset of the antennas required the reprocessing of static fixed solutions. 

Consequently, the antenna vertical offsets of the rover and PALM CORS have been adjusted to 

reduce confusion and ensure consistency in future processing. The initial vertical offset from the 

monument reference point to the electrical L1 phase center of the rover antenna was 0.165 m. 

Applying the standard measurement of 51.5 mm from the electrical L1 phase center to the 

Ashtech Marine L1/L2 rover antenna reference point (ARP) resulted in a new vertical offset 

adjustment of 0.131 m (M. Bryant, oral commun., March 29, 1999). This is based simply on the 

subtraction of the nonstandard 3.416-cm brass adapter between the rover ARP and the UNAVCO 

level mount. The vertical offset adjustment of the PALM CORS antenna from 0.0794 m to 

0.000 m was provided by Larry Hothem, USGS. The updated PALM CORS Station coordinates 

can be found in Appendix D of this report. Since all heights derived from GPS are relative to the 

Geodetic Reference System (GRS) 1980 reference ellipsoid and the International Terrestrial 

Reference Frame (ITRF) 1996 datum, computation of the geoid undulation using Earth Gravity 

Model (EGM) 1996 (Lemoine et al, 1997) was used to determine height above the geoid (mean 

sea level) for each survey marker. Appendix C of this report contains the geodetic coordinates 

and descriptions of each survey marker erected in a modified National Geodetic Survey format. 

To ensure that the condition and geodetic coordinates of the recently established survey markers 

are monitored, static surveys should be repeated periodically (at least, one marker every year on 

a rotational basis) by the ASA science technician. The resultant static data files and 

corresponding RINEX files should be zipped and transmitted by FTP to the USGS site in Reston, 

Va., for the postprocessing and updating of records. 

The RT-DGPS-based data capture system requires a clear path between the rover and PALM 

CORS radio signal, as well as to the satellites. Obstructions that block any of the three restrict 

the usefulness of RT-DGPS. Common signal problems in the radio transmission from a CORS 

are line-of-sight obstructions and out-of-range signal loss. To reduce signal loss from PALM 

CORS, a Pacific Crest radio receiver/transmitter (also know as a repeater) was used where these 

problems exist. To further enhance the range transmission, an amplifier was used and the radio 

antenna located on the northwest corner of the T-5 building roof was elevated from 2.4 m (8 feet) 

to 4 m (13 feet) above the deck. The ASA science technician and I carried out a series of tests on 

Biscoe Point and Cormorant and Dream Islands. On Cormorant Island, the amplified radio 

transmission signal from PALM CORS failed. The Pacific Crest repeater was set up on 

Christine Island, and the signal was successfully relayed to Cormorant. On other tests, I 

successfully received the amplified radio signal on Dream Island, but not on Biscoe. Tests 

should be conducted and recorded on a regular basis by the ASA science technician, especially

where the topographic relief or glaciers pose line-of-sight obstructions to the radio signal. 

On January 7, 1999, the ASA Science Technician assisted me in replacing the PALM CORS 

GPS antenna cone with a new protective dome-type cover to reduce distortion affects of the 

phase signal. Before-and-after tests were not conducted. Future comparison of recorded GPSdetermined positions before and after the installation should be considered. 

During the field period, an attempt was made to receive digital image data by way of the 

antiquated Palmer Station satellite communication link. During the two 5-hour windows at 38.4 

Kps transmission was so slow that it took 3 days to receive approximately 93 Mb of a Landsat 

image data. Because of the problem, a cruise vessel delivered the larger BAS scanned image 
files (150 Mb each) instead. The weak satellite communication link at Palmer Station needs to 

be brought up to current standards.

Experimentation with an OmniSTAR Model 3000LR12--an integrated RT-DGPS system for 

GPS observations and reception of broadcast range correction--was cancelled because the GPS 

engine failed. The RT-DGPS data collected before the failure showed promise. Because 

OmniSTAR (or similar systems) could prove useful in remote areas, its performance outside its 

network of reference stations should be investigated.

A laser range-finder unit, which was not delivered by the manufacturer in time to take to 

Antarctica, would have enabled the field team to automatically georeference and calculate

distance and bearing offsets of inaccessible features, such as high and low spot elevations in the 

Adθlie penguin colony. In addition, a field spectroradiometer would have enabled the collection 

of spectra as a means to differentiate Adθlie colonies from their surroundings in multispectral 

and hyperspectral imagery. Their value in the development of base line data is not examined in 

this paper. Because of the significance of both instruments for GPS- and GIS-based data 

collection, their value to mapping the pattern and trend of Adθlie penguin habitats and their 

relationship to regional climate change deserves a separate study of its own.

CONCLUSIONS

This study demonstrates the potential of GPS- and GIS-based data capture systems and promotes 

their use for acquiring ground truth data in Antarctica. With the added option of a field-equipped 

cellular (for example, Iridium) laptop computer, these captured data can be electronically 

transmitted in graphic and statistical form to the home office in the Washington, D.C. area or 

anywhere else. Making a wide array of geographically referenced information almost instantly 

available increases the opportunity for management and the scientific community to make better 

informed decisions. 

It is important to keep in mind, however, the limitations of field mapping technology, and to 

balance the criteria for its use against practical considerations of doing research on the Antarctic 

continent. For example, the environmental operating tolerance of laptop computers, the data 

volume of high-resolution image files, and the cost of field work, are present deterrents to 

expanding the use of field mapping in Antarctica. However, the downward cost trend of highspeed laptop computers equipped with multigigabyte storage hard disks and with operating 

temperatures of -20 degrees centigrade, as well as other hardware and software advances, should 

resolve some of these barriers. 

One should also keep in mind the fundamental limitations of satellite image and GPS coverage 

over Antarctica. Although the supply of commercially produced 1- to 4-m resolution satellite 

data will increase the information available to the scientific community, quality source data for 

doing a penguin census or achieving finer detail will have to come from low-altitude aerial 

photographs or declassified Government high-resolution reconnaissance satellite images. 

Furthermore, because of the inclination limits of most satellites, image coverage ends at about 80 

to 83 degrees south latitude. GPS-based data capture systems must have a clear path between the 

user and the satellites. Several environmental factors also affect the usefulness or availability of 
GPS signals. Critical factors include ionospheric interference caused by solar flares and the 

masking of signals caused by mountains. 

ACKNOWLEDGMENTS

The author would like to thank Bill Fraser, Donna Patterson, and Matt Irinaga, of the Polar 

Oceans Research Group; ASA employees Ron Nugent, Rob Edwards, Ken Doggett, Jeff Otten, 

Andy Sutton, and Lora Folger, plus many others at Palmer Station too numerous to list here. 

Also thanks for the offsite support provided by Jerry Mullins, Larry Hothem, and Cheryl Hallam, 

and other Polar Program staff of the USGS in Reston, VA, and Scott Borg and Polly Penhale, 

NSF, Arlington, Va. The NSF provided part of the funding for this project.

REFERENCES

Anderson, J.R., Hardy, E.E., Roach, J.T., and Witmer, R.E., 1976, "A land use and land cover 

classification system for use with remote sensor data:" U.S. Geological Survey Professional

Paper 964, 28 pp.

Arctowski, H., 1895, Observations sur l'interet que presente l'exploration geologique des Terres 

Australis: Soc. Geol. France Bull. 23, Ser. 3, p. 589-591.

Baumann, Chris, 1997, United States Antarctica Program Project S-085: Palmers CORS 1997, 

unpublished report, 13 pp.

Harrington, H.J., 1962, Geology and morphology of Antarctica: N.Z. Geol. Geophys., p. 1-70.

Lemoine, F.G., Smith, D.E., Kunz, L., Smith, R., Pavlis, E.C., Pavlis, N.K., Klosko, S.M., 

Chinn, D.S., Torrence, M.H., Williamson, R.G., Cox, C.M., Rachlin, K.E., Wang, Y.M., 

Kenyon, S.C., Salman, R., Trimmer, R., Rapp, R.H., and Nerem, R.S., 1997, The development 

of the NASA GSFC and NIMA Joint Geopotential Model: Gravity, Geoid and Marine Geoid and 

Marine Geodesy, vol. 117, International Association of Geodesy Symposia, pp. 461-469.

Sanchez, R.D., 1996, Satellite image integration with spatial base data: Proceedings of the 62nd 

Annual Convention of the Association of Photogrammetry and Remote Sensing, vol. 1, 

Baltimore, Md., pp. 489-498.

Sanchez, R.D. and Hothem, Larry, 1998, Field mapping using high-resolution digital images 

and global positioning system and geographic information system data: Proceedings of the 

Meeting of the American Society of Photogrammetry and Remote Sensing, Tampa Bay, Fa., 

March 1998, CD-ROM.

Soper, Tony, 1994, Antarctica: A guide to the wildlife: The Globe Pequot Press, Old Saybrook, 

Conn., 144 pp.
APPENDIX A

GPS INSTRUMENT ACCURACY CHECK DATA A-1

(ITRF-96 Datum, GRS-80 Ellipsoid)

* Recorded every 15 minutes; height of antenna 

 above PAL1 brass cap was 16.5 cm

ASTECH Z-12* 

 (RT-DGPS)

 64° 46 25.62635 S. 

 64° 02 47.77175 W.

 40.55 m

64° 46 25.62440 S.

64° 02 47.77103 W.

40.55 m

64° 46 25.62505 S.

64° 02 47.77105 W.

40.55 m

PLGR +96*

 (PPS)

 64° 02 47.76 W

 64° 46 25.57 S

34 m

 64° 02 47.76 W

64° 46 25.60 S

37 m

 64° 02 47.76 W

64° 46 25.61 S

40 m

PAL1 Survey Marker

Lat: 64°46 25.62400 S.

Long: 64°02 47.77092W.

Ellip. Height: 40.551 m

Difference, 

in meters

-0.073

-0.011

-0.002

-0.012

-0.001

-0.001

-0.033

-0.002

-0.001

Difference, 

in meters

 1.5

-0.1

 7

 0.3

-0.1

 1

 0.6

-0.1

 4
APPENDIX B

FIELD RECORD SUMMARY - ANTARCTIC PENNINSULA B-1

SITE NAME COORDINATES1 SURVEY MARKER STAMP MARKING

Biscoe Point LAT: 64° 48' 40.11730" S.

LON: 63° 46' 26.41684" 

W.

ELLIP. HT: 39.089 

meters

MSL: 23 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

BIS1-1999

Christine Island LAT: 64° 47' 37.30140" S.

LON: 64° 01' 12.71093" W.

ELLIP. HT: 34.018 meters

MSL: 18 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

CHR1-1999

Cormorant Island LAT: 64° 47' 36.37587" S.

LON: 63° 57' 58.38410" W.

ELLIP. HT: 47.668 meters

MSL: 32 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

COR1-1999

Dream Island LAT: 64° 43' 36.73074" S.

LON: 64° 13' 18.49024" W.

ELLIP. HT: 50.452 

meters

MSL: 35 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

DRE1-1999

Humble Island LAT: 64° 45' 54.87933" S.

LON: 64° 05' 17.04120" W.

ELLIP. HT: 31.139 meters

MSL: 15 meters

LAT: 64° 45' 53.30849" S.

LON: 64° 05' 02.01791" W.

ELLIP. HT: 25.552 meters

MSL: 10 meters

5/8" threaded rod with

red plastic cap

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

HUM1-1999

NSF-USAP-USGS

HUM2-1999

Litchfield Island LAT: 64° 46' 13.97135" S.

LON: 64°05' 38.85038" W.

ELLIP. HT: 64.424 

meters

MSL: 48 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

LIT1-1999

Palmer Station LAT: 64° 46' 27.20749" S.

LON: 64° 03' 06.13782" 

W.

ELLIP. HT: 29.570 meters

MSL: 14 meters

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

PMR1-1999

Torgersen Island LAT: 64° 46' 20.55260" S.

LON: 64° 04' 23.88481" 

W.

5/8" threaded rod with

red plastic cap

NSF-USAP-USGS

TOR1-1999

 

1

ITRF96/GRS80; mean sea level (MSL) heights were derived from EGM96 values and have a +/- 2 meter level of accuracy
ELLIP. HT: 33. 439 

meters

MSL: 17 meters
APPENDIX C

U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-1

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: BIS1

LOCATION: BISCOE POINT, ANVERS ISLAND

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 48 40.11730 S. 63 46 26.41684 W. ADJUSTED

MSL: 23 meters 76 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,202,906.266 (X) -2,441,831.079 (Y) -5,748,815.208 (Z) METERS

ELLIP. HEIGHT: 39.09 meters GPS OBS 

GEOID HEIGHT: 15.73 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted during postprocessing by 

the U.S. Geological Survey in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,812,368.144 463,243.747 meters 0.9996165 0 42 01.484

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: BIS1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - January 31, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990131 Monumented USGS (rds)

19990303 Good USAP (jco)

STATION DESCRIPTION

 

The survey marker is located about 13.8 km (8.5 mi) southeast of Palmer 

Station at Biscoe Point, on a ridge northwest of the boat landing site. To 

reach the marker from the landing, go northwest to a freshwater pond and 

climb up the rise to the survey marker on top of an outcrop. The marker is 

a stamped (BIS1-1999, NSF-USAP-USGS) red morasse plastic survey cap 

attached to a 5/8" stainless steel threaded rod embedded 12-cm into the 

bedrock. The rod setting meets standards for UNAVCO level mounts. 

Access: A permit to visit Biscoe Point is required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. The National Science 

Foundation administers the act and its permit system.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-2

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: CHR1

LOCATION: CHRISTINE ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 47 37.30140 S. 64 01 12.71093 W. ADJUSTED

MSL: 18 meters 59 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,193,173.097 (X) -2,448,557.707 (Y) -5,747,982.392 (Z) METERS

ELLIP. HEIGHT: 34.02 meters GPS OBS 

GEOID HEIGHT: 15.73 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted during postprocessing by 

the U.S. Geological Survey in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,814,146.884 451,521.804 meters 0.9996288 0 55 23.060

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: CHR1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 8, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990208 Monumented USGS (rds)

19990405 Good USAP (jco)

STATION DESCRIPTION

The survey marker is located about 2.8 km (1.7 mi) southeast of Palmer 

Station at Christine island, on a bluff southwest of the boat landing site. To 

reach the marker from the landing climb southwest over a rise to the survey 

marker on top of an outcrop. The marker is a stamped (CHR1-1999 NSFUSAP-USGS) red morasse plastic survey cap attached to a 5/8" stainless steel 

threaded rod embedded 12 cm into the bedrock. The rod setting meets 

standards for UNAVCO level mounts. 

Access: A permit to visit Christine Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. However, the National 

Science Foundation requests voluntary non-access to protect bird population.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-3

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: COR1

LOCATION: CORMORANT ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 47 36.37587 S. 63 57 58.38410 W. ADJUSTED

MSL: 32 meters 105 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,195,493.344 (X) -2,447,461.031 (Y) -5,747,982.535 (Z) METERS

ELLIP. HEIGHT: 47.67 meters GPS OBS 

GEOID HEIGHT: 15.73 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during postprocessing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,814,215.765 454,086.237 meters 0.9996258 0 52 27.221

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: COR1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 4, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990204 Monumented USGS (rds)

19990405 Good USAP (jco)

STATION DESCRIPTION

The survey marker is located about 4.5 km (2.8 mi) southeast of Palmer Station at 

Cormorant Island, on a steep ridge southwest of the boat landing site. To reach the 

marker from the landing, go southwest through an opening toward the highest 

precipice and climb up at west end of ridge to the marker embedded in an outcrop. 

The marker is a stamped (COR1-1999, NSF-USAP-USGS) red morasse plastic 

survey cap attached to a 5/8" stainless steel threaded rod embedded 12 cm into the 

bedrock. The rod setting meets standards for UNAVCO level mounts. 

Access: A permit to visit Cormorant Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. However, the National Science 

Foundation requests voluntary non-access to protect bird population.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-4

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: DRE1

LOCATION: DREAM ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 43 36.73074 S. 64 13 18.49024 W. ADJUSTED

MSL: 35 meters 115 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,187,483.827 (X) -2,458,815.652 (Y) -5,744,820.392 (Z) METERS

ELLIP. HEIGHT: 50.45 meters GPS OBS 

GEOID HEIGHT: 15.72 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during postprocessing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg

UTM 20 2,821,423.506 441,799.030 meters 0.9996415 1 06 17.590

MARKER: Red morasse plastic survey cap

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: DRE1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 1, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990201 Monumented USGS (rds)

19990219 Good USAP (jco)

STATION DESCRIPTION

The survey marker is located about 9.8 km (6.1 mi) northwest of Palmer 

Station at Dream Island, on a steep ridge south of the boat landing site. To 

reach the marker from the landing, walk south toward the highest precipice 

and climb to the highest point along the ridge to the marker embedded in an 

outcrop. The marker is a stamped (DRE1-1999, NSF-USAP-USGS) red 

morasse plastic survey cap attached to a 5/8" stainless steel threaded rod 

embedded 12 cm into the bedrock. The rod setting meets standards for 

UNAVCO level mounts. 

Access: A permit to visit Dream Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. However, the National 

Science Foundation requests voluntary non-access to protect bird population.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-5 

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: HUM1

LOCATION: HUMBLE ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 45 54.87933 S. 64 05 17.04120 W. ADJUSTED

MSL: 15 meters 49 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,191,525.270 (X) -2,452,549.348 (Y) -5,746,628.208 (Z) METERS

ELLIP. HEIGHT: 31.14 meters GPS OBS 

GEOID HEIGHT: 15.72 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during postprocessing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,817,263.499 448,242.516 meters 0.9996328 0 59 03.310

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: HUM1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 2, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990202 Monumented USGS (rds)

19990218 Good USAP (jco)

STATION DESCRIPTION

The survey marker is located about 2 km (1.2 mi) northwest of Palmer 

Station at Humble Island on a bluff west of the boat landing site. To reach 

the marker from the landing, walk west-southwest across the island toward 

the highest bluff and climb up to the marker embedded in an outcrop. The 

marker is a stamped (HUM1-1999, NSF-USAP-USGS) red morasse plastic 

survey cap attached to a 5/8" stainless steel threaded rod embedded 12 cm 

into the bedrock. The rod setting meets standards for UNAVCO level 

mounts. 

Access: A permit to visit Humble Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. However, the National 

Science Foundation requests voluntary non-access to protect bird population.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-6 

Palmer Station, Antarctic Peninsula Report Date: May 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: HUM2

LOCATION: HUMBLE ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 45 53.30849 S. 64 05 02.01791 W. ADJUSTED

MSL: 10 meters 33 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,191,722.090 (X) -2,452,499.995 (Y) -5,746,602.415 (Z) METERS

ELLIP. HEIGHT: 25.55 meters GPS OBS 

GEOID HEIGHT: 15.72 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during post-processing in May 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,817,315.525 448,440.178 meters 0.9996325 0 58 49.707

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: HUM2-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - January 29, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990520 Monumented USGS (jco)

STATION DESCRIPTION

The survey marker is located about 2 km (1.2 mi) northwest of Palmer 

Station at Humble Island on a bluff near the boat landing site. To reach the 

marker from the landing climb up to the telemetry hut; the marker is 

embedded in an outcrop about 15 meters NNE of the hut. The marker is a 

stamped (HUM2-1999, NSF-USAP-USGS) red morasse plastic survey cap 

attached to a 5/8" stainless steel threaded rod embedded 12 cm into the 

bedrock. The rod setting meet standards for UNAVCO level mounts. 

Access: A permit to visit Humble Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. However, the National 

Science Foundation requests voluntary non-access to protect bird population.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-7

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: LIT1

LOCATION: LITCHFIELD ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 46 13.97135 S. 64 05 38.85038 W. ADJUSTED

MSL: 48 meters 157 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,191,038.470 (X) -2,452,206.973 (Y) -5,746,910.367 (Z) METERS

ELLIP. HEIGHT: 64.42 meters GPS OBS 

GEOID HEIGHT: 15.74 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during postprocessing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,816,667.575 447,964.575 meters 0.9996332 0 59 23.195

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: LIT1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 9, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990209 Monumented USGS (rds)

19990412 Good USAP (jco)

STATION DESCRIPTION

The survey marker is located about 1.8 km (1.1 mi) northwest of Palmer 

Station at Litchfield Island, on a steep escarpment southwest of the boat 

landing site. To reach the marker from the landing, walk WSW across the 

island toward the highest precipice and climb until you reach the marker 

embedded in an outcrop about 8 m west of a rock cairn. The marker is a 

stamped (LIT1-1999, NSF-USAP-USGS) red morasse plastic survey cap 

attached to a 5/8" stainless steel threaded rod embedded 12 cm into the 

bedrock. The rod setting meets standards for UNAVCO level mounts. 

Ownership: A permit to visit Litchfield Island is required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. The National Science 

Foundation administers the Act and its permit system.
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-8

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: PWR1

LOCATION: PALMER STATION, ANVERS ISLAND

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 46 27.20749 S. 64 03  06.13782 W. ADJUSTED

MSL: 14 meters 46 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,192,684.932 (X) -2,450,977.697 (Y) -5,747,053.550 (Z) METERS

ELLIP. HEIGHT: 29.57 meters GPS OBS 

GEOID HEIGHT: 15.72 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during post-processing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,816,292.047 449,988.689 meters 0.9996306 0 57 05.144

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: PWR1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - January 30, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990130 Monumented USGS (rds)

19990412 Good USAP (jco)

STATION DESCRIPTION

To reach the marker from the Palmer Station pier, follow the road 

east to the T-5 building; the survey marker is located about 5 meters 

off (north side) the road between the GWR and T-5 buildings. The 

marker is a stamped (PWR1-1999, NSF-USAP-USGS) red morasse 

plastic survey cap attached to a 5/8" stainless steel threaded rod 

embedded 12 cm into a granite outcrop. The rod setting meets 

standards for UNAVCO level mounts. 
U.S. GEOLOGICAL SURVEY - ANTARCTIC CONTROL SHEET C-9 

Palmer Station, Antarctic Peninsula Report Date: April 26, 1999

*********************************************************************************************

ABN: This is a candidate for the Antarctic Base Network Control

DESIGNATION: TOR1

LOCATION: TORGERSEN ISLAND, ANVERS ISLAND AREA

MAP: (no published intermediate- or large-scale maps)

CURRENT SURVEY CONTROL

_____________________________________________________________________________________________

ITRF96/GRS80: 64 46 20.55260 S. 64 04 23.88481 W. ADJUSTED

MSL: 17 meters 56 feet

_____________________________________________________________________________________________

CARTESIAN COOR.: 1,191,843.242 (X) -2,451,596.239 (Y) -5,746,969.211 (Z) METERS

ELLIP. HEIGHT: 33.44 meters GPS OBS 

GEOID HEIGHT: 15.71 meters EGM96

The horizontal and vertical coordinates were established by GPS static survey and adjusted by the U.S. Geological 

Survey during post-processing in April 1999.

The orthometric height (H) = height above ellipsoid (h) - geoid/ellipsoid separation (N) at an accuracy level of +/- 2 

meters; N value was determined using program F477DOE.EXE with the input files for spherical harmonic potential 

coefficient set (EGM96) and spherical harmonic correction coefficients (CORRCOEF). The ellipsoidal height was 

determined by GPS observations and is referenced to ITRF96/GRS80; geoid height was determined by EGM96.

 South West Units Scale Converg.

UTM 20 2,816,480.809 449,988.689 meters 0.9996319 0 58 15.428

MARKER: Red morasse plastic survey cap 

SETTING: 5/8" stainless steel threaded rod extended 8 cm above bedrock

STAMPING: TOR1-1999, NSF-USAP-USGS

STABILITY: Most reliable and expected to hold position/elevation well

SATELLITE: Site selected for satellite observations - February 8, 1999

ROD/PIPE DEPTH: 12 centimeters

HISTORY: DATE CONDITION BY

19990208 Monumented USGS (rds)

STATION DESCRIPTION

The survey marker is located about 1 km (0.62 mi) west-northwest of Palmer 

Station at Torgersen Island, on a high mound east of the boat landing site. To 

reach the marker from the landing, walk east toward the mound of outcrops. The 

marker is a stamped (TOR1-1999, NSF-USAP-USGS) red morasse plastic survey 

cap attached to a 5/8" stainless steel threaded rod embedded 12 cm into the 

bedrock. The rod setting meets standards for UNAVCO level mounts. On a 

second mound about 8 m (26 ft) southwest of the marker is an A.R.A. (Armada 

De Republica Argentina) brass marker set in a concrete-filled coffee-can size 

container.

Ownership: A permit to visit Torgersen Island is not required under the Antarctic 

Conservation Act of 1978, Public Law 95-541. The National Science Foundation 

administers the Act and its permit system.