T-1452b; Topography of Puget Sound, Wash. Ter., From Robinson Pt. To South End of Vashon I., including Quatermaster’s Hbr., 1876-77

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-1452b; Topography of Puget Sound, Wash. Ter., From Robinson Pt. To South End of Vashon I., including Quatermaster’s Hbr., 1876-77

Geospatial_Data_Presentation_Form: map

Abstract:

Georeferenced United States Coast & Geodetic Survey Topographic Sheet T-1452b; Topography of Puget Sound, Wash. Ter., From Robinson Pt. To South End of Vashon I., including Quatermaster’s Hbr., 1876-77; Scale: 1:20,000; Surveyor: E. Ellicott

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: 1876-77

Time_Period_Information: 1876-77

Single_Date/Time:

Calendar_Date: 1876-77

Currentness_Reference: 1876-77

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: 1876-77

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: No traceable 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:

Nine possible benchmarks were identified on the T-sheet and in the NGS datasheets, but only four of these actually corresponded with benchmarks on the T-sheet, and all four could have been remounted. It is likely that STUMP, RICHMOND, and GREENBANK were remounted in the same positions as the original benchmarks, but none of these can be used for the benchmark error assessment.

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

1	PROSPECT 2	SY2883	1934	122 31 56.85139	47 25 46.44967	23.073591
2	STUMP	SY2884	1934	122 30 51.41456	47 25 06.03779	12.0845
4	RICHMOND 2	SY2871	1934	122 32 20.67753	47 22 36.46565	8.459462
9	GREENBANK	SY2342	1921	122 20 53.25737	47 24 58.65988	7.701715

Lineage:

Technician: Elizabeth Cassel Date: 10-02-03

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 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: 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:

Brown, 1921

Neill, 3, 1921

Pine, 1921

Lakota, 1921

Launch, 2, 1921

Heyer, 1921

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	33	47	26
2	122	32	47	26
3	122	31	47	26
4	122	33	47	25
5	122	32	47	25
6	122	31	47	25
7	122	30	47	25
8	122	29	47	25
9	122	28	47	25
10	122	27	47	25
11	122	26	47	25
12	122	21	47	25
13	122	20	47	25
14	122	19	47	25
15	122	33	47	24
16	122	32	47	24
17	122	31	47	24
18	122	30	47	24
19	122	29	47	24
20	122	28	47	24
21	122	27	47	24
22	122	26	47	24
23	122	25	47	24
24	122	24	47	24
25	122	23	47	24
26	122	22	47	24
27	122	21	47	24
28	122	20	47	24
29	122	19	47	24
30	122	33	47	23
31	122	32	47	23
32	122	31	47	23
33	122	30	47	23
34	122	29	47	23
35	122	28	47	23
36	122	27	47	23
37	122	26	47	23
38	122	25	47	23
39	122	24	47	23
40	122	23	47	23
41	122	22	47	23
42	122	21	47	23
43	122	20	47	23
44	122	19	47	23
45	122	33	47	22
46	122	32	47	22
47	122	31	47	22
48	122	30	47	22
49	122	29	47	22
50	122	28	47	22
51	122	27	47	22
52	122	26	47	22
53	122	25	47	22
54	122	24	47	22
55	122	23	47	22
56	122	22	47	22
57	122	21	47	22
58	122	20	47	22
59	122	19	47	22
60	122	34	47	21
61	122	33	47	21
62	122	32	47	21
63	122	31	47	21
64	122	30	47	21
65	122	29	47	21
66	122	28	47	21
67	122	27	47	21
68	122	26	47	21
69	122	25	47	21
70	122	24	47	21
71	122	23	47	21
72	122	22	47	21
73	122	21	47	21
74	122	20	47	21
75	122	19	47	21
76	122	34	47	20
77	122	33	47	20
78	122	32	47	20
79	122	31	47	20
80	122	30	47	20
81	122	29	47	20
82	122	28	47	20
83	122	27	47	20
84	122	26	47	20
85	122	25	47	20
86	122	24	47	20
87	122	23	47	20
88	122	22	47	20
89	122	21	47	20
90	122	20	47	20
91	122	26	47	19
92	122	25	47	19
93	122	24	47	19
94	122	23	47	19

Three different resamples were performed on this data. For the second resample, point 14 was removed because of high error distance (14 meters) and high RMS error (0.003). Then points 13 and 60 were removed for the third resample because of high error distances (around 11 meters). After the third resample, the rest of the points had RMS errors below 0.003 and error distances under 10 meters, so the third resample became the final resample.

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:

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

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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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