T-1953; Washington Sound, Thatcher Pass to Watmough Bight, Wash. Ter., 1889

Metadata:

Identification_Information
Data_Quality_Information
Spatial_Reference_Information
Distribution_Information
Metadata_Reference_Information

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-1953; Washington Sound, Thatcher Pass to Watmough Bight, Wash. Ter., 1889

Geospatial_Data_Presentation_Form: map

Abstract:

Georeferenced United States Coast & Geodetic Survey Topographic Sheet T-1953; Washington Sound, Thatcher Pass to Watmough Bight, Wash. Ter., 1889; Scale: 1:10,000; Surveyor: J.J. Gilbert

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 https://chartmaker.ncd.noaa.gov/hsd/shallow.htm

Time_Period_of_Content: 1889

Time_Period_Information: 1889

Single_Date/Time:

Calendar_Date: 1889

Currentness_Reference: 1889

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: 1889

Access_Constraints:

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

https://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.

https://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

Data_Quality_Information:

Positional_Accuracy:

Horizontal_Positional_Accuracy: 4.2 meters (using 8 reliable benchmarks)

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 https://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:

NGS datasheets were sought for thirty-seven benchmarks clearly marked on this 1:10,000 scale t-sheet. Only eight pertain to NGS records and were used for the error assessment. Note: SCRUB 2 is a remounted Benchmark

Station Name	PID	Date Mon/Obs	Longitude	Latitude	Distance***
BOULDER RESET	TR1757	1854	122 48 07.34055	48 25 56.34358	1.800839
CRAB RESET	TR1765	1889	122 50 40.61771	48 27 42.85824	3.243241
FORTRESS RESET	TR1767	1889	122 50 18.42941	48 27 54.78087	1.376471
JAMES SOUTH 1854	TR2058	1854	122 46 12.52732	48 30 31.27624	1.306278
KELLET 1889	TR1760	1889	122 48 02.35993	48 26 50.47295	3.993795
ROCK RESET	TR1755	1889	122 51 47.05913	48 29 43.51413	7.337073
SCRUB 2	TR2041	1939	122 51 13.83203	48 32 41.03163	5.802706
WHITE ROCK RESET	TR2030	1889	122 46 55.78514	48 32 17.24064	10.334952

*** Measured distance (m) between T-sheet benchmark & NGS-published benchmark

Lineage:

Technician: Soleil Kelley Date: 10.10.2003

Process_Step:

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

Scanned images were obtained from Information Manufacturing Corporation, 7000 Infantry Ridge Road, Suite 200, Manassas, VA 20109 Phone: (703) 393-6866

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: https://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:

Iceberg, 1854

James North, 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
	deg	min	deg	min
1	122	51	48	33
2	122	50	48	33
3	122	51	48	32
4	122	50	48	32
5	122	49	48	32
6	122	48	48	32
7	122	47	48	32
8	122	46	48	32
9	122	51	48	31
10	122	50	48	31
11	122	49	48	31
12	122	48	48	31
13	122	47	48	31
14	122	46	48	31
15	122	52	48	30
16	122	51	48	30
17	122	50	48	30
18	122	49	48	30
19	122	48	48	30
20	122	47	48	30
21	122	46	48	30
22	122	52	48	29
23	122	51	48	29
24	122	50	48	29
25	122	49	48	29
26	122	48	48	29
27	122	52	48	28
28	122	51	48	28
29	122	50	48	28
30	122	49	48	28
31	122	48	48	28
32	122	52	48	27
33	122	51	48	27
34	122	50	48	27
35	122	49	48	27
36	122	48	48	27
37	122	47	48	27
38	122	49	48	26
39	122	48	48	26

Several resamples were performed on this data. The first resample had low error distance in general, with the exception of points 5, 7, 8 and 15, which had errors of 6.5, 6, 9.5 and 6.8 meters respectively (RMS of first resample is 0.0018). These points were removed for the second resample, and the overall RMS reduced to 0.0014. Error distances decreased in general, although the distance increased on those points that were removed for resample # 2.

At least three areas of original scanned image (t1953_crop) are very blurry, so the original scanned image t1953_sid (much larger file and more clear) was resampled using the same tic marks as above (except #39, which was illegible). The resulting RMS was 0.0825 and error distances were much higher than the first two resamples of t1953_crop. Tics 1, 2, 8, 10, 11, 36, 37 and 38 were then removed for resample # 4 (RMS of 0.0604). After discarding these points the error distances decreased on more than half the tics, although error distances were still much greater than the first two resamples.

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 JPG 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)

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

Distribution_Information:

Resource_Description: Downloadable Data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 24.630

Metadata_Reference_Information:

Metadata_Date: 20020723

Metadata_Contact: