Año Nuevo to Santa Cruz, California –A Photographic Tour of the Coastline

by Henry Chezar and Florence L. Wong

U.S. Geological Survey Digital Data Series DDS-61
Version 1.0

Quick Start

Note: The interactive maps do not seem to work with Firefox; use Internet Explorer or Safari instead.

Introduction

From 1995 to 1999 the United States Geological Surveyconducted a multifaceted scientific study of theseafloor geology and geologic processes within theMonterey Bay National Marine Sanctuary. Included in thisstudy and presented here is a digital photographic surveydocumenting the coastal morphology and stratigraphy between Point AñoNuevo and Santa Cruz, California, with precision-navigated overlappingimages. Another part of the study is producing a digitaldatabase of seafloor geologic maps. A comparison of thenewly acquired seafloor maps and coastline images provides ameans of visualizing the transition from sea to land.

The more than 500 digital coastline images included onthis CD-ROM are linked by interactive location maps. TheHTML and image files are also accessible by standardbrowser and image software.

Photographic Method

The sea-level images of the coast were collected fromaboard the research vessel RV David Johnston onNovember 4, 1998. We motored from Año Nuevo southward to Santa Cruz at an average speed of 12 knots (22km/hr) and acquired more than 500 overlapping,high-resolution digital images. Each photograph encompassesapproximately 200 m of coastline depending on the distancefrom shore. Overlaps between adjacent photographs aretens of meters.

The photographs were taken with a 35-mm high-resolutiondigital camera connected to a portable global positioningsystem (GPS) receiver with a horizontal accuracy of lessthan 3 meters. For most of the images, the GPS data (date,time of day, latitude, longitude, and altitude) arerecorded in the upper left corner of the image. The GPSdata are of the ship positions only and are best read onthe higher-resolution (300 dpi) images. Because of therapid camera firing rates needed to acquire overlappingimages, the GPS information would sometimes be missing,duplicated or erroneous because of inadequate satellitedownload time. In those situations, an interpolatedposition is inserted in the sequence log (photolog.txt).As all images were taken at sea level, the altitude data oneach image should be ignored.

The images were captured in Kodak compressed TIFF format.Each image, when uncompressed with Kodak software, has afile size of 4.5 Mb (megabytes). To fit all the images onone CD-ROM, each TIFF file was desampled and converted to ahigh-quality JPEG (xxx.jpg) image that is just under 1 Mbin size (300 dots per inch at 3 x 5 inch). A second set ofimages was desampled to about 30 to 50 kb (72 dots per inchat 4 x 5 inch) for more rapid viewing.

View the Images

The images are linked to a series oflocation maps. The hierarchy of links looks likethis:

Regional map (92 kb)

Detailed map (window x)

72 dpi image

300 dpi image

The regional map displays the 23 areas into which thephotographic images were divided. Each number on theregional map is a link to a detailed map (for example,window 8) that includes a sequence of about 30 images withan overlap of 5 images (for example, windows 8 and 9 have 5images in common). Each of the points on a detailed map islinked to a 72 dpi version of the image captured at thatlocation. Along with each 72 dpi image another link willdisplay the higher-resolution 300 dpi image.

Use the Images

The maps and images may be viewed directly with commonlyavailable browser and image software. To use an image inanother application, use the "Save image as" feature ofyour browser or go directly to the image files. The imagesand other files are arranged in folders or directories onthis CD-ROM as follows:


 Folder

Description

[top level]1_readme.txt: explanatory text file
index.htm: this file
ver_hist.txt: publication version history
data

photolog.txt is atext list of the GPS data transcribed from the photographicimages. If the location was interpolated, the ESTfield equals 1. Overlapping duplicate images (DUPL = 1)are omitted from the interactive presentation but existin the 72 dpi and 300 dpi directories.
j498mbpt consists of the data from photolog.txtconverted to an ArcInfo point coverage in UTM coordinates, which was used toconstruct all the maps in this presentation. The data areincluded as shapefiles (j498mbpt.dbf, j498mbpt.shx,j498mbpt.shp) and an ArcInfo export file(j498mbpt.e00). Equivalent files in geographic units (latitude/longitude)are included with prefix 'j498_ll'.
j498mbpt.met is themetadata file.
windmnmx.txt lists thegeographic extent of the index maps.
geo2utm.prj lists theprojection parameters.

html1

HTML files that include theregional map and detailed map pages

html2

HTML files to display each image;070xxx.htm displays 72 dpi images and 300xxx.htm displays300 dpi images

images

images other than the photographs

72dpi

573 photographs in JPEG format (0xxx.jpg) with aresolution of 72 dots per inch

300dpi

573 photographs in JPEG format(0xxx.jpg) with a resolution of 300 dots per inch


For otherinformation on the USGS work in the Monterey Bay NationalMarine Sanctuary, visit http://walrus.wr.usgs.gov/mbms.

Acknowledgments

The authors would like to thank Captain Gordon Smith ofthe R/V David Johnston, Mike Diggles, Susan Mayfield, SteveEittreim and Roberto Anima for their contributions to theproduction of this publication.

Any use of trade, product, or firm names in thispublication is for descriptive purposes only and does not implyendorsement by the U.S. Government.

Feel free to use the images but please cite this publication:

Chezar, Henry, and Wong, Florence L., 2000, Año Nuevo toSanta Cruz, California - a photographic tour of thecoastline: U.S. Geological Survey Digital Data SeriesDDS-61; 1 CD-ROM.

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Henry Chezar
Florence L. Wong
U.S. Geological Survey
Coastal and Marine Geology
345 Middlefield Road, MS 999
Menlo Park, CA 94025
http://walrus.wr.usgs.gov

updated 3/27/2007 (mfd)