T-2193; Topography of Washington Sound, Wash, Stuart Spieden and Other Islands, 1894

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-2193; Topography of Washington Sound, Wash, Stuart Spieden and Other Islands, 1894

Geospatial_Data_Presentation_Form: map

Abstract:

Georeferenced United States Coast & Geodetic Survey Topographic Sheet T-2193; Topography of Washington Sound, Wash, Stuart Spieden and Other Islands, 1894; 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 http://chartmaker.ncd.noaa.gov/hsd/shallow.htm

Time_Period_of_Content: 1894

Time_Period_Information: 1894

Single_Date/Time:

Calendar_Date: 1894

Currentness_Reference: 1894

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: 1894

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

Data_Quality_Information:

Positional_Accuracy:

Horizontal_Positional_Accuracy: 4 meters (using 11 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 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:

Sixteen possible benchmarks were identified in the datasheets and on the map, but two of these could have been remounted: GROOVE 2 and SHEEP 2, although these names match the names on the map. Three of these benchmarks did not match the map: PASTURE, SPIEDEN, and DOUGLAS. This is probably due to surveying errors, since these benchmarks lie on the outskirts of the t-sheet. All the other benchmarks were monumented during the production year of the map, and match very well. The error without remounts for this map is 4.14 meters.

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

1	TURN PT LIGHTHOUSE	Obs.1942	TR2294	123 14 14.64609	48 41 19.63469	1.21875
2	DANDY RESET	1894	TR2309	123 12 56.23043	48 41 23.55728	2.427061
3	PITCH RESET	1894	TR2308	123 13 07.94984	48 40 13.39298	1.591297
4	PUDDING RESET	1894	TR2306	123 11 25.96047	48 41 07.52953	5.042882
5	STUMP RESET	1894	TR2299	123 10 31.18379	48 40 49.94192	5.220153
6	ANT RESET	1894	TR2310	123 09 47.58450	48 40 26.85983	3.53125
7	GROOVE 2	1942	TR2307	123 11 02.68215	48 39 29.88790	3.579455
8	JOHN RESET	1894	TR2303	123 09 31.53899	48 39 58.16851	4.039357
9	RIPPLE RESET	1894	TR2298	123 07 49.30028	48 39 26.21657	1.068
10	CACTUS 1894	1894	TR2203	123 07 31.12634	48 38 52.92167	7.985888
11	SHEEP 2	1942	TR2296	123 08 06.68707	48 38 14.93090	10.236462
14	BARREN RESET	1894	TR2263	123 09 38.22998	48 37 21.30599	3.686043
15	VINE RESET	1894	TR2312	123 09 43.96352	48 38 48.59341	9.721965

Lineage:
Technician: Elizabeth Cassel Date: 9-24-03
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:

Tom, 1894

Tiptop, 1894

Fairfax, 1894

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	123	14	48	42
2	123	13	48	42
3	123	14	48	41
4	123	13	48	41
5	123	12	48	41
6	123	11	48	41
7	123	10	48	41
8	123	13	48	40
9	123	12	48	40
10	123	11	48	40
11	123	10	48	40
12	123	9	48	40
13	123	8	48	40
14	123	11	48	39
15	123	10	48	39
16	123	9	48	39
17	123	8	48	39
18	123	7	48	39
19	123	10	48	38
20	123	9	48	38
21	123	8	48	38
22	123	7	48	38

Three resamples were performed on this data. Because this was originally a SID image, the RMS values worked on a different scale, and the resamples were done with a cell output size of 1 by 1. The first resample had very high error distances (up to 13 m) on some points, and RMS values over 0.1. I eliminated points 15, 18, 21, and 22. The second resample had much better error distances, which were all under 4.5, and the RMS values all dropped below 0.07. For the final resample, I just adjusted a few of the points for a better fit.

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)

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: 2.000000

Ordinate_Resolution: 2.000000

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1927

Ellipsoid_Name: Clarke 1866

Semi-major_Axis: 6378206.400000

Denominator_of_Flattening_Ratio: 294.978698

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: