Volcanoes of the Wrangell Mountains and Cook Inlet Region, Alaska—Selected Photographs

By Christina Neal, Robert McGimsey, and Michael F. Diggles

Digital Data Series DDS-39
Version 1.1


U.S. Department of the Interior
Gale A. Norton, Secretary

U.S. Geological Survey
Charles G. Groat, Director

index map, Wrangell Mountains
Figure 1. Map showing volcanoes of the Wrangell Mountains represented in this collection of images.

index map, Cook Inlet
Figure 2. Map of Cook Inlet volcanoes represented in this collection of images.


This publication is an online version of a CD—ROM publication, U.S. Geological Survey Digital Data Series DDS-39. The data for this publication total 467 MB.


Alaska is home to more than 40 active volcanoes, many of which have erupted violently and repeatedly in the last 200 years. This CD—ROM contains 97 digitized color 35-mm images which represent a small fraction of thousands of photographs taken by Alaska Volcano Observatory scientists, other researchers, and private citizens. The photographs were selected to portray Alaska’s volcanoes, to document recent eruptive activity, and to illustrate the range of volcanic phenomena observed in Alaska.

These images are for use by the interested public, multimedia producers, desktop publishers, and the high-end printing industry. The digital images are stored in the “images” folder and can be read across Macintosh, Windows, DOS, OS/2, SGI, and UNIX platforms with applications that can read JPG (JPEG - Joint Photographic Experts Group format), TIF (TIFF – Tagged Image File Format), or PCD (Kodak’s PhotoCD (YCC) format) files. Throughout this publication, the image numbers match among the file names, figure captions, thumbnail labels, and other references. Also included on this CD—ROM are Windows and Macintosh viewers and engines for keyword searches (Adobe Acrobat Reader with Search). At the time of this publication, Kodak’s policy on the distribution of color-management files is still unresolved, and so none is included on this CD—ROM. However, using the Universal Ektachrome or Universal Kodachrome transforms found in your software will provide excellent color. In addition to TIF and PhotoCD (PCD) files, this CD—ROM contains large (14.2”x19.5”) and small (4”x6”) screen-resolution (72 dots per inch; dpi) images in JPEG format. These undergo downsizing and compression relative to the TIF and PhotoCD images. Each of these resolutions is located in the following folders:

  • TIF format: /images/TIF/ (1.72 GB)
  • PhotoCD format (PCD’s): /images/PCD/
  • JPG files (landscape, 1024 pixels wide; portrait, 768 pixels high): /images/JPG/large_screen/
  • JPG files (landscape, 432 pixels wide; portrait, 432 pixels high): /images/JPG/small_screen/

    Feel free to use any of these images but please cite the photographer and the U.S. Geological Survey.


    This CD—ROM presents 97 photographs showing volcanic activity and features in the Wrangell Mountains and Cook Inlet region. The images are presented in a variety of ways:

  • an “album” in Web-browser (HyperText Markup Language; HTML) format
  • a “book” in Adobe Acrobat (PDF) format that contains text, figures, captions, references, and a glossary
  • a “slideshow” in PDF format
  • as individual images in folders containing TIF-format, Kodak PhotoCD (PCD) image-pac-format and JPG-format files


    The content within this publication is presented in several formats all but one of which are accessible to sight-disabled people. The file “slideshow.pdf” is an image-only PDF and therefore has no tags and is not accessible but these images are the same as those presented in the files “album.html”, “DDS-39.pdf”, and “DDS-39-WEB.pdf” all of which are fully accessible using assistive technology such as screen readers and comply with the requirements of the Americans with Disabilities Act, Section 508.

    Album in Web-browser (HTML) Format

    An “album” is provided here as an HTML file. It consists of the 97 photographs with captions. Each image is first presented as a 4”x6” image. If you click on any 4”x6” image, it will bring up a larger version (14” wide or 10” high). Use your browser’s “Back” button to return to the album. The color “palate” contains 16.7 million colors.

    View the Web-browser album (album.html; 48 KB with links to 19.5 MB of image files)

    Presentations in Acrobat (PDF) Format

    To view PDF files on this CD—ROM, you will need Adobe Acrobat Reader which is provided in the “Acrobat” folder on the CD—ROM version of this publication for both Macintosh and Windows (version 5.0). Both users of the CD—ROM and online version of this publication can download the latest version or Acrobat Reader for free using the button below.

    Get Acrobat Reader

    Book in Acrobat (PDF) Format

    The “book” is provided here as an Adobe Acrobat PDF file (DDS-39.pdf). It is the same collection of photographs but each image is print-quality (3072x2048 pixels; 4”x6” 512 dpi) and it contains text, figures, captions, references, and a glossary.

    View the Acrobat book (DDS-39.pdf; 21.2 MB)

    If you are viewing this publication on the Web and do not have a fast connection, you can view a small screen-resolution version of the book. This file will not print well but it will download more quickly.

    View the screen-resolution book (DDS-39-WEB.PDF; 1.8 MB).

    Slideshow in Acrobat (PDF) Format

    The “slideshow” is provided in the “slideshow” folder as an Adobe Acrobat PDF file (slideshow.pdf). It is the same collection of photographs but each image is 1024 pixels wide or 768 pixels high so they will fill most large screens. To run it, you need to open it directly with Acrobat Reader rather than through this HTML front end with its browser “plugin.” To do this, quit (or minimize) this page, go directly to the CD—ROM, open the slideshow folder, and open the file “slideshow.pdf” (8.3 MB).

    If you are viewing this publication on the Web, download the slideshow.pdf file to your hard disk where you can open it directly with Acrobat Reader.

    View the slideshow file (slideshow/slideshow.pdf; 8.3 MB) and download it by right-clicking (PC) or clicking-and-holding or dragging-and-dropping (Mac).

    Tip: To automate slideshow, open Acrobat Reader, select Edit, Preferences, General, Full Screen... and check Advance Every 3 Seconds. Then open the slideshow. To exit the slideshow PDF file. To exit the slideshow at any time, hit the “Esc” button.

    (Old versions of Acrobat Reader such as 4.0 have the automate choice under File, Preferences, Full Screen).

    Individual Images

    The small-screen images (432 pixels in the long dimension) used in the HTML album, the large-screen images (landscape, 1024 pixels wide; portrait, 768 pixels high) used in both the HTML and PDF slideshow, and print-quality (3072x2048 pixels) images in TIF and PCD format and used in the PDF book are available individually using the links below.

    View the collection of small-screen images (images/JPG/small_screen; 2.1 MB total)
    View the collection of large-screen images (images/JPG/large_screen; 17.4 MB total)
    View the collection of TIF files; 6-megapixels (images/TIF; 1.72 GB total)
    View the collection of PCD files; 6-megapixels (images/PCD; 416 MB total)

    Kodak PhotoCD (PCD) Files: How to Use the Five Sizes

    For users who have commercial software that can read and print PCD files, the photographs are provided on this CD-ROM in that format in the “PCD” folder which is in the “images” folder.

    Each PCD file has five resolutions of images contained within each file. You can make a choice as to which one you want to use rather than needing to down-sample an image that is larger than you need. For example, when you open a PCD file in Adobe Photoshop, you get a dialog box where you select the resolution of your choice and then that version of the image opens.

    You can also use the largest of the choices, for instance, to make a poster-sized hard copy on a large plotter. Do this by opening a PCD in high-resolution mode (3072 x 2048 pixels) and setting the image size to 90 dpi and you will get a picture that is nearly two-feet by three-feet.

    In the hierarchy of file formats, PhotoCD (YCC) resides above BMP, EPS, GIF, JPEG, MOV, PCX, PICT, PSD, TIF, TIFF, etc., enabling end users to go from YCC to other formats, but not in the other direction without losing image quality. Each 24-bit color image is stored as 5 resolutions:

    1. Thumbnail [192 x 128 pixels]—Contact-sheet-size images for quick previewing of the entire collection.

    2. FPO “For Placement Only” [384 x 256 pixels]—A proxy for high-resolution images to determine placement in page-layout programs.

    3. Screen Resolution [786 x 512 pixels]—Ideal for computer viewing and multimedia projects.

    4. HDTV High-Definition Television [1536 x 1024 pixels]—Sufficient resolution for high definition TV, newspapers, and high-quality half-page layouts.

    5. High Resolution [3072 x 2048 pixels]—Provides the printing industry with resolution sufficient for high-quality full-page layouts at 300 dpi/150 lpi and 24-bit color.


    The captions for each image, besides being included in the HTML front end and the PDF file, are provided in ASCII format in the captions.txt file.

    View the Captions file for this CD—ROM (captions.txt; 20 KB)

    Information About this Publication

    Color scanning was done on a Kodak(3) PIW scanner. The resulting PCD files were edited in Adobe Photoshop 6.0 for Macintosh and converted JPG files. They were also converted to TIF format with Lemke Software's GraphicConverter v4.4. The small-screen images were made with JPG compression set to 3; the large-screen images were made with JPG compression set to 9. The “book” PDF file was constructed using Adobe PageMaker 7.0 page-layout software for Macintosh. The PDF’s were tagged using the Make Accessible plug-in for Adobe Acrobat 5.0 for Windows after which the alternative text was hand tagged. The master for the CD—ROM was made on a LaCie CDBP-16104A CD—ROM recorder using Roxio Toast Titanium 5.0.1 software for Macintosh set at ISO-9660 Level II CD—ROM format with Macintosh names (compatible with Windows) and Apple Extensions.


    Compiling a set of images from the AVO collection onto CD—ROM was first proposed by Joe Dorava. The authors have benefited greatly from the technical assistance, tenacity, and enthusiasm of John Nakata and Evelyn Newman. Reviews of caption text by Chris Nye, John Nakata, Jim Smith, and Lee Siebert improved their content. Map figures were generated by Anne Vanderpool and Kathy Lemke. Bernadette Johnson painstakingly labeled several sets of duplicate 35-mm slides. Mark Lohnes ably scanned the images. Bobbie Myers designed the volcanoes banner. We thank all the photographers who shared their work with us.
    View the version history of this publication (version_history.txt; 4 KB).
    View the Readme file for this CD—ROM (1_README.TXT; 20 KB).
    This publication consists of the online version of a CD—ROM publication that contains, in addition to the information on this Web site, CD—ROM-autoplay files for Windows, installer software for Adobe Acrobat Reader,and a search index. The data for this publication total 516 MB on the CD—ROM. The CD—ROM is available for sale by writing:

    USGS Information Services
    Box 25286, Federal Center
    Denver, CO 80225
    telephone: 303-202-4210; e-mail: infoservices@usgs.gov
    or calling

    1- 888-ASK-USGS (1-888-275-8747)
    ISBN 0607-86087-1

    Current pricing information is available from http://mapping.usgs.gov/esic/prices/.

    The URL of this report is https://pubs.usgs.gov/dds/dds-39/, where any updates to it can also be found.

    Date created: July 26, 2001
    Last modified: July 2, 2009 (mfd)

    Email content questions about this publication to the senior author, Christina Neal, (tneal@usgs.gov), U.S. Geological Survey.

    Email technical questions about this publication to Michael F. Diggles (mdiggles@usgs.gov), U.S. Geological Survey.

    Maintained by: Michael Diggles (mdiggles@usgs.gov), U.S. Geological Survey.

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