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

Metadata:


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 http://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.

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: 4.2 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 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:

 

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) 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:

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 1st 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:

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:


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