Surficial Geology Interpretive Map based on Sidescan-Sonar Imagery and Sediment Samples

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: David C. Twichell
Publication_Date: 20000000
Title: Surficial Geology Interpretive Map based on Sidescan-Sonar Imagery and Sediment Samples
Publication_Information:
Publication_Place: Woods Hole, MA
Publisher: U.S. Geological Survey
Description:
Abstract:
Two 21-day field operations were conducted in 1997 and 1998 in the estuaries and on the inner continental shelf off the northern Oregon and southern Washington coast. These cruises aboard the R/V Corliss were run in order to generate reconnaissance maps of the seafloor geology and the shallow subsurface stratigraphy using sidescan-sonar and seismic-reflection mapping techniques. The 1998 cruise also collected sediment grab samples, bottom photographs, and video images to verify the sidescan-sonar imagery and to document the seafloor geology. The combination of these data with previously collected sediment sample data (Robert, 1974; Nittrouer, 1978; and Smith et. al., 1980) has been used to define the extent and lithology of shelf sediments associated with the Columbia River littoral cell. This work is one component of a larger project studying the erosion of the Washington Oregon coasts and is being coordinated by the U.S. Geological Survey and the Washington State Department of Ecology. The reasons for collecting these data are to provide a regional synthesis of the offshore geology for this project and to support a wide variety of management decisions and to provide a basis for further process-oriented investigations.
Purpose:
This GIS overlay represents the surficial geology interpretive map of the inner shelf off the coast of southern Washington and northern Oregon. This interpretation is based on the integration of sidescan-sonar imagery, sediment sample data, and seismic-reflection data.
Supplemental_Information:
Roberts, R.W., 1974, Marine sedimentological data of the Washington continental shelf: University of Washington, Department of Oceanography Special Report 57, 129p.

Nittrouer, C.A., 1978, The process of detrital sediment accumulation in a continental shelf environment: an examination of the Washington shelf: PhD Thesis, University of Washington, Seattle, WA. 243p.

Smith, J.M., Messmer, L.W., Phipps, J.B., Samuelson, D.F., and Schermer, E.D., 1980, Grays Harbor and Chehalis River improvements to navigation environmental studies - Grays Harbor ocean disposal study: literature review and preliminary benthic sampling: U.S. Army Corps of Engineers Internal Report.

Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19740000
Ending_Date: 19980000
Currentness_Reference: 1998
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -124.500000
East_Bounding_Coordinate: -123.800000
North_Bounding_Coordinate: +47.350000
South_Bounding_Coordinate: +45.900000
Keywords:
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: ArcView
Theme_Keyword: shapefile
Theme_Keyword: polygon
Theme_Keyword: interpretation
Theme_Keyword: surficial geology
Theme_Keyword: marine sand
Theme_Keyword: marine siltston
Theme_Keyword: wisps
Theme_Keyword: megaripples
Theme_Keyword: lower beach face
Theme_Keyword: inner shelf sand
Theme_Keyword: mud
Theme_Keyword: gravel patch
Theme_Keyword: outcrop
Place:
Place_Keyword_Thesaurus: General
Place_Keyword: Pacific Ocean
Place_Keyword: Washington
Place_Keyword: Oregon
Place_Keyword: WA
Place_Keyword: OR
Place_Keyword: Columbia River
Place_Keyword: Columbia River littoral cell
Place_Keyword: Inner shelf
Temporal:
Temporal_Keyword_Thesaurus: General
Temporal_Keyword: Tertiary
Temporal_Keyword: Holocene
Temporal_Keyword: Modern
Temporal_Keyword: Quaternary
Access_Constraints: None
Use_Constraints:
The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David C. Twichell
Contact_Organization: U.S. Geological Survey
Contact_Position: Oceanographer
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
Woods Hole Field Center
384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: dtwichell@usgs.gov

Data_Quality_Information:
Logical_Consistency_Report:
This interpretation was based on a combination of datasets. Interpretive boundaries are most closely constrained where they cross sidescan-sonar imagery lines.
Completeness_Report:
The interpretation of the inner shelf in this study has a maximum coverage extent equal to that of the sidescan-sonar imagery coverage.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The most accurate interpretation boundaries are where those boundaries cross the sidescan-sonar imagery data. Other boundaries are interpolated based on sediment sample information.
Lineage:
Process_Step:
Process_Description:
This interpretive map was drawn interactively in ArcView as a series of polygons and saved as an ArcView shape file. The basis for the interpretive boundaries was the backdrop of sidescan-sonar imagery and sediment sample analyses information.
Process_Date: 19990000
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David C. Twichell
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survery
Woods Hole Field Center
384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: dtwichell@usgs.gov

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector

Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0.00018
Longitude_Resolution: 0.00026
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257222101
Vertical_Coordinate_System_Definition:
Depth_System_Definition:
Depth_Datum_Name: Local surface
Depth_Resolution: 2
Depth_Distance_Units: Meters
Depth_Encoding_Method: Attribute values

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: interp.dbf
Entity_Type_Definition: ArcView shapefile attribute table
Entity_Type_Definition_Source: ESRI
Attribute:
Attribute_Label: Class
Attribute_Definition:
This field is the classification of the surficial geology represented on the seafloor at that location. The values are as follows:

jetty-- man made structure

wisps-- modern bedform off the mouth of the Columbia River; bands of moderate backscatter (as seen in the sidescan-sonar imagery) superimposed on a backgroun of low backscatter

megaripples-- modern bedform off the mouth of the three bays in the study area; 2-4 m wavelengths with crestlines oriented roughly parallel to bathymetric contours

lower beach face-- modern textural unit occuring along the shoreward edge of the study area; seaward limit is defined where the mean grain size becomes finer than 3 phi

inner shelf sand-- modern textural unit seaward of the lower beach face unit; seaward limit defined where the sediment mud content exceeds 25%

mud-- modern textural unit typically along the seaward edge of the study area; defined where sediement mud content exceeds 25%

gravel patches-- areas where sediment content contains grain sizes from 2 mm up to 2 cm

outcrop-- includes all types of pre-Quaternary strata exposed on the seafloor

Attribute_Definition_Source: Data interpreter - David C. Twichell
Attribute_Domain_Values:
Unrepresentable_Domain: character set

Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy Soderberg
Contact_Organization: U.S. Geological Survey
Contact_Position: Data Librarian
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
Woods Hole Field Center
384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700
Contact_Facsimile_Telephone: 508-457-2313
Contact_Electronic_Mail_Address: nsoderberg@usgs.gov
Resource_Description: U.S. Geological Survey CD-ROM Open-File Report
Distribution_Liability:
This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Although all data published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: ARCV
File_Decompression_Technique: No compression applied
Digital_Transfer_Option:
Offline_Option:
Offline_Media: CD-ROM
Recording_Capacity:
Recording_Density: 650
Recording_Density_Units: MBytes
Recording_Format: ISO 9600 with Rock Ridge extensions
Compatibility_Information: UNIX, DOS, MAC
Fees: none at this time
Technical_Prerequisites:
This interpretation is available in ArcView shapefile format. The user must have ArcView, Arc Explorer, or another GIS package capable of importing and reading these data.

Metadata_Reference_Information:
Metadata_Date: 20000119
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
Woods Hole Field Center
384 Woods Hole Rd
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: 19940608

Generated by mp on Tue Jan 25 17:06:50 2000