T-2302; Washington Sound, Part of Lopez Island, Big Rock to Point Colville, Washington Territories, 1897

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Reference_Information
• Distribution_Information
• Metadata_Reference_Information

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Identification_Information:

Citation:

Citation_Information:

Originator: Puget Sound River History Project

Originator: Department of Earth & Space Sciences, University of Washington, Box 351310

Originator: Seattle, WA 98195

Publication_Date: 10/01/03

Title: T-2302; Washington Sound, Part of Lopez Island, Big Rock to Point Colville, Washington Territories, 1897

Geospatial_Data_Presentation_Form: map

Abstract:

Georeferenced United States Coast & Geodetic Survey Topographic Sheet T-2302; Washington Sound, Part of Lopez Island, Big Rock to Point Colville, Washington Territories, 1897

Supplemental_Information: For a comprehensive historical and technical review of the production and interpretation of early Coast & Geodetic Survey T-sheets please refer to Shalowitz, A.L. 1964. Shore and Sea Boundaries, Volumes 2. U.S. Department of Commerce, U.S. Coast and Geodetic Survey, Washington, DC. This publication is available online at http://chartmaker.ncd.noaa.gov/hsd/shallow.htm

Time_Period_of_Content: 1897

Time_Period_Information: 1897

Single_Date/Time:

Calendar_Date: 1897

Currentness_Reference: 1897

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Keywords:

Theme:

Theme_Keyword: T-sheets

Theme_Keyword: Coastal Survey

Theme_Keyword: Land Cover

Theme_Keyword: Historical

Theme_Keyword: United States Coast and Geodetic Survey

Place:

Place_Keyword: Washington State

Place_Keyword: Puget Sound

Stratum:

Stratum_Keyword: Near Shore

Stratum_Keyword: Coast

Temporal:

Temporal_Keyword: 1897

Access_Constraints:

This georeferenced image may be freely downloaded and used. Please give credit to the Puget Sound River History Project, University of Washington.

http://riverhistory.ess.washington.edu

Use_Constraints:

This georeferenced image may be freely downloaded and used. Please give credit to the Puget Sound River History Project, University of Washington.

http://riverhistory.ess.washington.edu

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Brian Collins, Amir Sheikh

Contact_Organization:

Department of Earth and Space Sciences, University of Washington

Contact_Address:

Address_Type: mailing address

Address: Department of Earth and Space Sciences

Address: Box 351310

Address: University of Washington

City: Seattle

State_or_Province: WA

Postal_Code: 98195

Country: USA

Contact_Voice_Telephone: (206) 616-6584

Contact_Facsimile_Telephone: (206) 543-0489

Contact_Electronic_Mail_Address: bcollins@u.washington.edu

Contact_Electronic_Mail_Address: asheikh@u.washington.edu

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Data_Quality_Information:

Positional_Accuracy:

Horizontal_Positional_Accuracy: 3 meters (using 5 reliable benchmark)

To assess an independent check of the accuracy of the registration process, benchmarks located on the T-sheets were compared to published NGS benchmarks that were retraceable to the time of the surveyed T-sheet. (Published NGS benchmark information is located at http://www.ngs.noaa.gov/cgi-bin/datasheet.prl). Only benchmarks that could be established with a high degree of certainty that existed at the time of the original T-sheet survey and were not remounted were used in the final accuracy measurement. If no current benchmarks exist or if the benchmarks have been remounted in relation to the benchmarks on the T-sheet, hard points (areas that would expect little change since the original surveys) were used to give a general indicator of the T-sheet’s registration accuracy in lieu of a more rigorous method. Thus these hard point measurements must be viewed with some caution. It should be stressed that the accuracy assessment was to check the accuracy of the overall registration process, not necessarily the accuracy of the survey itself.

NOTE: Measured distances are rounded to the nearest meter. The hand-drawn representations of benchmarks on the T-sheets are often up to 10 meters in width. To assess an independent check of the accuracy of the registration process, the measured distance is from the NGS-published coordinates to the perceived middle of the benchmark depicted on the T-sheet. In addition, the overall shape of the benchmark symbol is sometimes obscured by other symbology on the T-sheet. Thus, there is a certain level of uncertainty introduced due to the ambiguous location of the benchmark on the T-sheet.

Horizontal_Positional_Accuracy_Report:

Ten possible benchmarks were identified on the T-sheet and in the NGS datasheets , but only nine of these actually corresponded with benchmarks on the T-sheet, and two could have been remounted. It is likely that HAR(TR1786) is the same position as the original benchmark.

Benchmark PID LONG LAT Measured distance between T-sheet benchmark & NGS-published benchmark

HAR	TR1786	122 55 16.50071	48 27 08.25081	2.576941
LONG	TR1796	122 55 30.20268	48 26 27.53657	0
PLANE 1897	TR1798	122 55 50.41353	48 26 29.92089	1.505199
CHANNEL 1897	TR1794	122 54 40.62094	48 26 49.63155	2.663593
NOISY RESET	TR1783	122 53 21.06423	58 26 10.89930	0
RICHARDSON RESET	TR1787	122 53 52.87863	48 26 45.78315	1.9375
ICEBERG RESET	TR1785	122 53 05.01669	48 25 11.52820	11.258504
SMALL ISLAND 1897	TR1784	122 52 40.90123	48 26 24.43600	3.615424
WINDY RESET	TR1754	122 52 21.69280	48 26 39.73464	2.042756
SOUTHEAST ISLAND	TR1775	122 49 17.75931	48 24 54.55344	0

Lineage:

Technician: Isabelle Yasmina Sarikhan Date: 9-29-03

Process_Step:

Process_Description: The georeferencing of T-sheets in the Puget Sound region was funded by the Puget Sound Nearshore Project (PSNERP) http://www.pugetsoundnearshore.org/

Scanned images were obtained from University of Washington Libraries at http://www.wsulibs.wsu.edu/holland/masc/sanjuanindex.html

The methodology used to georeference the T-sheets was modified from the previous work of Jennifer Burke (NOAA) in the Lower Columbia and Daniels et al (2001). The georeferencing and error assessment process were carried out using Erdas Imagine 8.6 and ArcGIS 8.3. For additional information concerning the georeferencing method please refer to: http://rocky2.ess.washington.edu/riverhistory/tsheets.php

Datum Shift:

Most T-sheets do not have a current datum represented on them (i.e. NAD 27, NAD 83). Graticules (tics) marking Latitude and Longitude in the early local Puget Sound Datum (PSD) and a later update to North American Datum (NAD) projection are most often present. To calculate the X, Y shift from NAD to NAD 27, X and Y values were used from datum difference tables for survey stations around most of Puget Sound (Patton, 1999). An overall datum shift was determined for the area covered by the T-sheet by averaging the shift from a number of survey stations in or nearby that area represented on the T-sheet.

The following survey stations were used to calculate the datum shift:

Southeast Island 1854

Iceberg 1854

Boulder, 1854

Registration:

For georeferencing, tics were used only surrounding areas that depicted nearshore features on the T-sheet. This was mainly done to hasten the overall process due to the magnitude of the scope of the project while maintaining the best control around areas of interest. The sheets were then rectified using a 1^st order polynomial transformation. Points that produced relatively high RMS values, as well as tic points that consistently fell outside of 4.5 meters (on a 1:10,000 scale T-sheet) of their projected UTM coordinates were omitted.

The following tic marks were used for georeferencing the initial resample:

	Longitude		Latitude		Longitude	Latitude
	deg	min	deg	min	dd	dd
1	122	58	48	29	122.96667	48.48333
2	122	58	48	28	122.96667	48.46667
3	122	57	48	29	122.95000	48.48333
4	122	57	48	28	122.95000	48.46667
5	122	57	48	27	122.95000	48.45000
6	122	56	48	30	122.93333	48.50000
7	122	56	48	29	122.93333	48.48333
8	122	56	48	28	122.93333	48.46667
9	122	56	48	27	122.93333	48.45000
10	122	56	48	26	122.93333	48.43333
11	122	55	48	30	122.91667	48.50000
12	122	55	48	29	122.91667	48.48333
13	122	55	48	28	122.91667	48.46667
14	122	55	48	27	122.91667	48.45000
15	122	55	48	26	122.91667	48.43333
16	122	55	48	25	122.91667	48.41667
17	122	54	48	30	122.90000	48.50000
18	122	54	48	29	122.90000	48.48333
19	122	54	48	28	122.90000	48.46667
20	122	54	48	27	122.90000	48.45000
21	122	54	48	26	122.90000	48.43333
22	122	54	48	25	122.90000	48.41667
23	122	54	48	24	122.90000	48.40000
24	122	53	48	30	122.88333	48.50000
25	122	53	48	29	122.88333	48.48333
26	122	53	48	28	122.88333	48.46667
27	122	53	48	27	122.88333	48.45000
28	122	53	48	26	122.88333	48.43333
29	122	53	48	25	122.88333	48.41667
30	122	53	48	24	122.88333	48.40000
31	122	52	48	28	122.86667	48.46667
32	122	52	48	27	122.86667	48.45000
33	122	52	48	26	122.86667	48.43333
34	122	52	48	25	122.86667	48.41667
35	122	52	48	24	122.86667	48.40000
36	122	51	48	28	122.85000	48.46667
37	122	51	48	27	122.85000	48.45000
38	122	51	48	26	122.85000	48.43333
39	122	51	48	25	122.85000	48.41667
40	122	51	48	24	122.85000	48.40000
41	122	50	48	26	122.83333	48.43333
42	122	50	48	25	122.83333	48.41667
43	122	49	48	25	122.81667	48.41667

Six different resamples were performed on this data. The RMS errors were all below 0.003 after the first resample, but a few points had error distances around 7 meters. After removing all the high error points and error distances systematically, the final resample was determined as the best of the resamples with the lowest error.

The image was then reprojected to UTM ZONE 10N NAD83/HARN using a rigorous transformation.

Several factors that can introduce error into the registration process include:

• The accuracy of the graticules and projection lines drawn on the map.

• Non-uniform shrinkage of the original map due to age and storage conditions.

• Distortion caused by the scanning process.

• Loss of resolution and distortion due to image compression.

• Ability of the technician to identify appropriate survey stations that correspond to the area of the T-sheet to compute the datum shift.

• Ability of the technician to identify and locate appropriate tics on the T-sheet for the transformation.

• The geometric transformation method employed.

References:

Daniels, R. C. and R.H. Huxford. 2001. An error assessment of vector data derived from scanned National Ocean Service topographic sheets. Journal of Coastal Research 17: 611 – 619.

Patton, R.S., 1999. Datum Differences: Atlantic, Gulf, and Pacific Coast of the United States. U.S. Department of Commerce, U.S. Coast and Geodetic Survey, Washington D.C. (Original publication: 1936)

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Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 10

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.999600

Longitude_of_Central_Meridian: -123.000000

Latitude_of_Projection_Origin: 0.000000

False_Easting: 500000.000000

False_Northing: 0.000000

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: row and column

Coordinate_Representation:

Abscissa_Resolution: 3.000000

Ordinate_Resolution: 3.000000

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257222

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Distribution_Information:

Resource_Description: Downloadable Data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 24.630

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Metadata_Reference_Information:

Metadata_Date: 20020723

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Brian Collins, Amir Sheikh

Contact_Organization:

Department of Earth and Space Sciences, University of Washington

Contact_Address:

Address_Type: mailing address

Address: Department of Earth and Space Sciences

Address: Box 351310

Address: University of Washington

City: Seattle

State_or_Province: WA

Postal_Code: 98195

Country: USA

Contact_Voice_Telephone: (206) 616-6584

Contact_Facsimile_Telephone: (206) 543-0489

Contact_Electronic_Mail_Address: bcollins@u.washington.edu

Contact_Electronic_Mail_Address: asheikh@u.washington.edu

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

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