File 'gpr2011-001_readme.PDF' contains file names and definitions, map numbers and grid correlations, projection information, location figures, and much general information. In case the text version of 'gpr2011-001_readme.txt' needs to be used, the location figures are provided as jpegs in the main directory. Some detailed information about the data is given in the 'Entity_and_Attribute_Information' section of this metadata file. 'Ladue_linedata.txt' gives information on the linedata in an easy-to-read format. All data are provided in NAD27, UTM zone 7N, except for Google Earth KMZ files, which are in Geographic Coordinate System (Simple Cylindrical projection) with a WGS84 datum. Besides NAD27, UTM zone 7N easting and northing coordinates, the linedata files also include latitude and longitude (Geographic Coordinate System with a WGS84 datum).
This publication, GPR2011-1, contains the data types or files given below.
***********************************************************LINEDATA Geosoft binary GDB and Geosoft ASCII XYZ format
***********************************************************GRIDS, GEOTIFFS, GOOGLE EARTH FILES, VECTORS
File names and general definitions for the raster and vector files are given below. Not all files listed below are included in each format listed above. Grid files are provided in Geosoft binary GRD and ER Mapper ERS formats. Vector files are provided in an ESRI shape file format.
All file names listed below start with 'Lad_'.
NAME GENERAL DEFINITION mag_diu Pre-final total magnetic field (without leveling and before IGRF removal) mag_rmi Residual magnetic field with IGRF removed (nT) magigrf Total magnetic field with IGRF removed (nT) 1vd First vertical derivative (calculated vertical gradient) of the total magnetic field with IGRF removed (nT/m) asig Analytic signal calculated from the total magnetic field with IGRF removed (nT/m) tiltder Tilt derivative of total magnetic field with IGRF removed (degrees) res56k Apparent coplanar resistivity for 56,000 Hz (56 kHz; ohm-m) res7200 Apparent coplanar resistivity for 7200 Hz (ohm-m) res900 Apparent coplanar resistivity for 900 Hz (ohm-m) dtm Digital terrain or elevation model (m) SecGrid Alaska PLSS Section Grid for map sheets (vector only) UTMGrid NAD27, UTM zone 7N grid (vector only) fp Flight path (vector only) **********************************************************MAPS PDF and HPGL/2 formats
The thirteen maps at 1:63,360-scale need two sheets to cover the survey area. Maps are generally produced in two versions, one with data contours and no topography and one with topography and no data contours. Not all images are provided as maps. File 'gpr2011-001_readme.PDF' contains a table linking the map numbers with the data and map version. This information is also in the 'Detailed_Description' section for the maps.
Burns, L.E., Fugro Airborne Surveys Corp., and Fugro GeoServices, Inc., 2011, LADUE SURVEY AREA: Magnetic and Electromagnetic Line, Grid, and Vector Data and Maps, Fortymile mining district, Tanacross Quadrangle, eastern Alaska (DIGHEM [V] SURVEY): Geophysical Report GPR 2011-1, State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (DGGS), Fairbanks, AK, USA.Online Links:
Planar coordinates are encoded using row and column
Abscissae (x-coordinates) are specified to the nearest 25
Ordinates (y-coordinates) are specified to the nearest 25
Planar coordinates are specified in meters
The horizontal datum used is North American Datum of 1927.
The ellipsoid used is Clarke 1866.
The semi-major axis of the ellipsoid used is 6378206.4.
The flattening of the ellipsoid used is 1/294.978698.
Each linedata file contains raw and processed linedata, and related calculated fields. Missing data are represented with the dummy variable '*'. Each of the 197 flight lines or partial flight lines (e.g., Line 10701, referred to as 'LINE' attribute) is associated with a 'DATE' (e.g., 2010/08/13), a 'FLIGHT (number)' (e.g., 19023), and a particular multi-record set of data. Each record represents data acquisition from one spatial location in the flight line. A total of 1,521,961 records are present in each data file.
//Flight 19003 //Date 2010/08/05 Line 10010 (or 'Tie 10950', etc.) Followed by all records for points sampled along Line 10010. (Pattern is repeated for each line number).The 'ID CELL' content, particularly combined with the definitions below for this particular survey, provides information about the flight line layout. (Source: L.E. Burns & Fugro Airborne Surveys)
Definitions of the 'LINE' and 'FLIGHT' attributes are listed below.
LINE TYPES and SYMBOLS:
Traverse lines – oriented nominally N10W (350 degrees);
Tie lines - oriented nominally N80E (80 degrees); and
Border lines - present inside and parallel to the survey
tract border where traverse or tie lines
are not parallel to the border.
Traverse lines – 'L' (GDB file); 'LINE' (XYZ file).
Tie and border lines - 'T' (GDB file); 'TIE' (XYZ file).
LINE NUMBERS
Planned flight lines increase by 10 in a consistent fashion.
For this project, traverse line numbers increase from SW to
NE; tie line numbers increase from north to south; and
border line numbers increase in a clockwise direction.
When more than one uninterrupted flight traverse was needed
to complete a planned flight line, the fifth digit of the line
number is increased by '1' for each new flight segment/version.
MAIN LINE NUMBERS:
Lowest Traverse Lines: L10010 (southwest)
Highest Traverse Lines: L11670 (northeast)
Lowest Tie Lines: T19010 (north)
Highest Tie Lines: T19140 (south)
Lowest Border Lines: T19150 (long northwestern edge near
middle of map,increasing in clockwise direction
Highest Border Lines: T19230 (southwest)
------------------------------------------------------------
'FLIGHT' DESIGNATORS
The 5 digit flight designator consists of a two digit Fugro
Dighem (V) system number (19 for this project) and a three
digit flight identification number, e.g., '003'.
Range of values | |
---|---|
Minimum: | 443032.79 |
Maximum: | 500104.81 |
Units: | m |
Range of values | |
---|---|
Minimum: | 7015944.02 |
Maximum: | 7086091.42 |
Units: | m |
The attribute measurement resolution is 0.1 second. The values increase from the beginning of a flight to the end. Only FIDs during production flights are included in the database.
Range of values | |
---|---|
Minimum: | 63.2705237 |
Maximum: | 63.9026360 |
Units: | degrees |
Range of values | |
---|---|
Minimum: | -142.1398096 |
Maximum: | -141.0000640 |
Units: | degrees |
Range of values | |
---|---|
Minimum: | 19003 |
Maximum: | 19031 |
Units: | flight |
Range of values | |
---|---|
Minimum: | 2010/08/05 |
Maximum: | 2010/08/22 |
Units: | day |
Range of values | |
---|---|
Minimum: | 18.26 |
Maximum: | 151.50 |
Units: | m |
Range of values | |
---|---|
Minimum: | 15.28 |
Maximum: | 173.10 |
Units: | m |
Range of values | |
---|---|
Minimum: | 549.08 |
Maximum: | 1592.67 |
Units: | m |
Range of values | |
---|---|
Minimum: | 521.96 |
Maximum: | 1562.32 |
Units: | m |
Range of values | |
---|---|
Minimum: | 57269.86 |
Maximum: | 57374.94 |
Units: | nT |
Range of values | |
---|---|
Minimum: | -61.54 |
Maximum: | 43.54 |
Units: | nT |
Range of values | |
---|---|
Minimum: | 53878.68 |
Maximum: | 61530.04 |
Units: | nT |
Range of values | |
---|---|
Minimum: | 53878.68 |
Maximum: | 61530.04 |
Units: | nT |
Range of values | |
---|---|
Minimum: | 53887.40 |
Maximum: | 61526.71 |
Units: | nT |
Range of values | |
---|---|
Minimum: | 57090.90 |
Maximum: | 57302.59 |
Units: | nT |
Range of values | |
---|---|
Minimum: | -3325.10 |
Maximum: | 4307.60 |
Units: | nT |
Range of values | |
---|---|
Minimum: | 53881.38 |
Maximum: | 61514.08 |
Units: | nT |
Range of values | |
---|---|
Minimum: | -378.19 |
Maximum: | 320.98 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -20.26 |
Maximum: | 381.16 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -80.90 |
Maximum: | 88.45 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -29.45 |
Maximum: | 113.52 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -73.62 |
Maximum: | 223.17 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -32.99 |
Maximum: | 230.20 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -274.88 |
Maximum: | 803.47 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -71.20 |
Maximum: | 865.84 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -117.77 |
Maximum: | 1803.49 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -67.61 |
Maximum: | 1764.63 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -382.31 |
Maximum: | 322.51 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -0.76 |
Maximum: | 381.11 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -78.55 |
Maximum: | 85.25 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -0.30 |
Maximum: | 114.69 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -72.50 |
Maximum: | 221.74 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -2.83 |
Maximum: | 229.07 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -274.87 |
Maximum: | 803.45 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | 3.44 |
Maximum: | 865.91 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | -107.83 |
Maximum: | 1803.54 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | 7.83 |
Maximum: | 1764.63 |
Units: | ppm |
Range of values | |
---|---|
Minimum: | 3.50 |
Maximum: | 1325.00 |
Units: | ohm·m |
Range of values | |
---|---|
Minimum: | 7.83 |
Maximum: | 10418.24 |
Units: | ohm·m |
Range of values | |
---|---|
Minimum: | 6.98 |
Maximum: | 18992.55 |
Units: | ohm·m |
Range of values | |
---|---|
Minimum: | -83.04 |
Maximum: | 294.39 |
Units: | m |
Range of values | |
---|---|
Minimum: | -72.13 |
Maximum: | 86.89 |
Units: | m |
Range of values | |
---|---|
Minimum: | -69.42 |
Maximum: | 24.82 |
Units: | m |
Range of values | |
---|---|
Minimum: | -42.99 |
Maximum: | 84.49 |
Units: | unitless |
Range of values | |
---|---|
Minimum: | -36.05 |
Maximum: | 45.41 |
Units: | unitless |
Range of values | |
---|---|
Minimum: | 0.00 |
Maximum: | 0.00 |
Units: | unitless |
Range of values | |
---|---|
Minimum: | 0.00 |
Maximum: | 0.00 |
Units: | unitless |
Range of values | |
---|---|
Minimum: | 0.00 |
Maximum: | 0.00 |
Units: | unitless |
Two supporting files, a Geosoft projection file (GI) and a Geosoft-produced metadata file (XML), are included for each Geosoft grid file. The Geosoft grid is viewable (or importable into other software) without using these supported files. When using Geosoft, the GI file automatically sets the projection of the grid if the GI file is placed in the same directory as the grid file (GRD). Setting the projection can also be done manually in Geosoft without the GI file.
Each ER Mapper grid consists of two files, a header (projection) file (.ERS) and a data file (no extension). Both ER Mapper files are necessary to view a grid or to convert it to another software format. (Source: Fugro Airborne Surveys)
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Grid file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
Geotiff file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
KMZ file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file
vector file containing lines for all flight lines
vector file containing lines and numbers for major FIDs and beginning and ending FIDs
vector file containing lines for minor FIDs
vector file containing lines for alphanumeric characters
vector file containing alphanumeric characters
file containing alphanumeric characters
Two map sheets, labeled 'A' and 'B', are needed to cover the survey area at a scale of 1:63,360 (inch-to-a-mile). Thirteen different maps (26 map sheets) are included in this publication. Bounding coordinates for the sheets are given immediately below.
** 'A' maps –northern part of area ******
West, -141.83 East, -141.00 North, 63.93 South, 63.58** 'B' maps – southern part of area *******
West, -142.17 East, -141.00 North, 63.58 South, 65.25Authors and titles of the maps are like the example given below:
Burns, L.E., Fugro Airborne Surveys Corp., and Fugro GeoServices, Inc., 2011, Residual magnetic field of the Ladue Survey Area, Fortymile mining district, eastern Alaska, part of Tanacross quadrangle: Alaska Division of Geological & Geophysical Surveys Geophysical Report 2011-1-1A, 1 sheet, scale 1:63,360.
Most geophysical images are placed on two maps; one with topography and one with data contours and no topography. A table clearly showing information about the maps (numbers, type of image, and whether topography or data contours are included) is located in 'gpr2011_001_readme.pdf' included with this publication.
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
map in PDF and HPGL/2 format
Funding was provided by the Alaska State Legislature as part of the DGGS Airborne Geophysical/Geological Mineral Inventory (AGGMI) program.
(907) 451-5020 (voice)
The survey was part of the Alaska Airborne Geophysical/Geological Mineral Inventory project funded by the Alaska State Legislature and managed by State of Alaska, Department of Natural Resources (DNR), Division of Geological & Geophysical Surveys (DGGS). The project seeks to catalyze private-sector mineral development investment. The project delineates mineral zones on Alaska state lands that: 1) have major economic value; 2) can be developed in the short term to provide high quality jobs for Alaska; and 3) will provide economic diversification to help offset the loss of Prudhoe Bay oil revenue.
Akima, H., 1970, A new method of interpolation and smooth curve fitting based on local procedures: Journal of the Association of Computing Machinery v. 7, no. 4.Online Links:
- None
Alaska Department of Natural Resources - Land Records Information Section, 1995, Alaska PLSS Section Grid: State of Alaska, Department of Natural Resources, Division, Land Records Information Section (LRIS), <http://mapper.landrecords.info/> (Anchorage, Alaska).Online Links:
- <ftp://ftp.dnr.state.ak.us/asgdc/adnr/pls_section.zip>
- <http://dnr.alaska.gov/SpatialUtility/SUC?cmd=vmd&layerid=45> (metadata)
Flights were performed with an Aerospatiale AS-350-B3 helicopter at a mean terrain clearance of 200 feet (61 m) along N10W (350 degrees) survey flight lines with one-quarter mile (402.3 m) line spacing. Tie lines were flown perpendicular to the flight lines at intervals of approximately 3 miles (4,828 m). Traverse line coverage was 3,003.8 mi (4,834.2 km) and tie line coverage 395.8 mi (637.0 km) for a total of 3,399.6 km (5,471.2 km) of data. This distance includes overlapping reflight segments but not any rejected portions of lines.
A Novatel OEM4-G2L Global Positioning System was used for navigation and flight path recovery. The helicopter position was derived every 0.5 seconds (2 Hz); the ground GPS base station data were collected at 0.1 second (10 Hz) intervals. The use of the differentially-corrected base station data results in a positional accuracy of better than five meters. The positional xy data are interpolated from 2 Hz to 10 Hz. Flight path positions were projected onto the Clarke 1866 (UTM zone 7N) spheroid, 1927 North American datum using a central meridian (CM) of 141 degrees, a north constant of 0, and an east constant of 500,000.
Data sources used in this process:
The calculated magnetic tilt grid (Lad_TiltDer) is the angle between the horizontal gradient and the total vertical gradient, and is useful for identifying the depth and type of magnetic source. The tilt angle is positive over the source, crosses through zero at, or near, the edge of a vertical sided source, and is negative outside the source zone. It has the added advantage of responding equally well to shallow and deep sources and is able to resolve deeper sources that may be masked by larger responses caused by shallower sources.
The first vertical derivative grid was calculated using a fast Fourier transform (FFT) based frequency-domain filtering algorithm. The vertical gradient algorithm enhances the response of magnetic bodies in the upper 500 m and attenuates the response of deeper bodies. The resulting (calculated) vertical gradient grid ('Lad_1VD') provides better definition and resolution of near-surface magnetic units and helps to identify weak magnetic features that may not be evident in the total field data.
All magnetic and derivative derivative magnetic grids were then resampled from the 80-m cell size down to a 25-m cell size using a modified Akima (1970) technique to produce the maps and final grids contained in this publication.
Data sources used in this process:
Data sources used in this process:
Data sources used in this process:
Burns, L.E., Fugro Airborne Surveys Corp., and Stevens Exploration Management Corp., 2006, Line, grid, and vector data and plot files for the airborne geophysical survey of parts of the Alaska Highway corridor, east-central Alaska: Geophysical Report GPR 2006-6, State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (DGGS), Fairbanks, AK, USA.Online Links:
Staff, DGGS, Corp., Geoterrex-Dighem, and Stevens Exploration Management Corp., 1999, CD-ROM containing profile and gridded data and section lines of the 1998 geophysical survey data for part of the Fortymile mining district, Alaska, southern Eagle and northern Tanacross quadrangle: Public Data File DGGS PDF 99-9, State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (DGGS), Fairbanks, AK, USA.Online Links:
Survey contracts specified the conditions and specifications under which these data were collected. Altimeter, heading, lag, and frequent EM calibrations were done. More information will be available in the project report to be published in the future.
The helicopter position was derived every 0.5 seconds using post-flight differential positioning to an accuracy of better than 1 m.
The laser altimeter ('ALTLAS_BIRD'), located in the bird (EM equipment and magnetometer housing), had a stated resolution of 0.10 meter. The ALTLAS_BIRD value may be unreliable over bodies of water where the laser returns are scattered.
The file 'LADUE.GDB' contains 1,521,961 records with 50 channels each. Channel names and definitions of all 50 channels are included in 'Ladue_linedata' in .TXT and .PDF format, and the 'Entity_and_Attribute_Information' section of this metadata.
Almost all items were sampled at 0.1 sec. intervals. Five of the following six channels were sampled at intervals larger than 0.1 sec. and contain interpolated data. The diurnal_cor channel conTAINS
CHANNELS CONTAINING INTERPOLATED VALUES
*************************************** X_NAD27z7n (location information; interp. from 0.5 sec.) Y_NAD27z7n (location information; interp. from 0.5 sec.) lat_WGS84 (location information; interp. from 0.5 sec.) lon_WGS84 (location information; interp. from 0.5 sec.) diurnal_filt (diurnal filter; interp. from 1.0 second-sampled 'diurnal_filt') diurnal_cor (the correction applied based on the interpolated 'diurnal_filt' channel)Few values are missing from the databases. CHANNELS WITH MISSING VALUES IN 'LADUE.GDB' Channel Data Null Values Values
***************************************** mag_raw 1521958 3 cpsp 1521956 5 cxsp 1521954 7 difi 1521954 7 difq 1521954 7 diurnal_filt 1521943 18 cppl 1521928 33 mag_lag 1521881 80 mag_diu 1521881 80 mag_rmi 1521881 80 magigrf 1521881 80 res56K 1521860 101 res7200 1521860 101 res900 1521860 101 dep56k 1518636 3325 dep7200 1441221 80740 dep900 760902 761059Missing magnetic values occur in the database for the Ladue survey area because of the lagging process, at the beginning of some lines, and due to despiking. Missing values in the apparent resistivity (res56k, res7200, and res900) and associated calculated 'depth' (dep56k, dep7200, and dep900) are due to calculations being meaningless, generally caused by increase in altitude.
Data for this survey were collected by a single subcontractor (Fugro Airborne Surveys) who was responsible for collecting and processing the data. All the data were collected with the same instruments (magnetometers, electromagnetic bird and sensors, gamma ray spectrometer, altimeters, and navigational system).
Are there legal restrictions on access or use of the data?
- Access_Constraints:
- This report, map and/or dataset are available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).
- Use_Constraints:
- Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way the user is obligated to describe the types of modifications the user has made. User specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (DGGS).
907-451-5020 (voice)
907-451-5050 (FAX)
dggspubs@alaska.gov
Geophysical Report 2011-1
The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products, any failure thereof, or otherwise, and in no event will the State of Alaska's liability to the requester or anyone else exceed the fee paid for the electronic service or product.
Maps from current publications are available on paper or Mylar. Please ask for the maps to be printed from HPGL/2 files to ensure the best quality image. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turn around time is 1-2 weeks unless special arrangements are made and an express fee is paid. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount.
Data format: | Geosoft binary float (GRD) (version Unknown) |
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DVD
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Data format: | ER Mapper (ERS) (version Unknown) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | Geosoft binary database (GDB) (version Unknown) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | Geosoft ASCII (XYZ) (version Unknown) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | ESRI Shape (SHP) (version Unknown) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | MapInfo Professional Tab (TAB) (version Unknown) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | PDF (version 1.5) |
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Media you can order: |
DVD
(format Unspecified)
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Data format: | HPGL/2 (version unknown) |
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Network links: |
<http://dx.doi.org/10.14509/22562> |
Media you can order: |
DVD
(format Unspecified)
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Digital files on DVD are available for $10 plus shipping and are available for no charge when downloaded.
Order by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: cash, check, money order, VISA, or MasterCard. The geophysics page of the DGGS website (<http://www.dggs.alaska.gov/pubs/geophysics>) has geophysical order forms for this project and others.
Digital downloads: less than 30 minutes for most files. Free FTP access is available upon request for files not available on the web. Offline CD/DVD-ROMs: 1-2 weeks unless special arrangements are made and an express fee is paid.
Custom views or processing may be requested. Please contact Laurel Burns by phone (907-451-5021), e-mail (laurel.burns@alaska.gov), or fax (907-451-5050) to discuss custom processing availability, fees, and turnaround time.
Software with ability to use, import, or convert Geosoft float GRD, Geosoft binary GDB or ASCII XYZ files, Autocad DXF files, ESRI Shape files, MapInfo Professional TAB files, Adobe Acrobat PDF, Google Earth files, and text files. Free downloadable interfaces to view or convert the gridded and dxf files are available at the Geosoft website (<http://www.geosoft.com>; Oasis Montaj viewer). The KMZ files can be dragged and dropped into the 'My Places' folder of the free downloadable 'Google Earth' software. Freeware software 'printfile' (<http://www.lerup.com/printfile>) prints HPGL/2 files easily on compatible printers. The HPGL/2 files have brighter colors and sharper topography than the PDF maps and should be used for printing when possible. The PDF format maps are the only maps digitally viewable in this publication.
907-451-5021 (voice)
907-451-5050 (FAX)
dggspubs@alaska.gov