GEORECTIFIED 1982 AERIAL PHOTOGRAPHS OF THE UPPER TEXAS GULF OF MEXICO

Metadata also available as

Metadata:
Identification_Information:
Citation:
Citation_Information:
Originator: University of Texas at Austin Bureau of Economic Geology (BEG)
Publication_Date: January 2003
Title:
GEORECTIFIED 1982 AERIAL PHOTOGRAPHS OF THE UPPER TEXAS GULF OF MEXICO
Edition: first
Geospatial_Data_Presentation_Form: remote-sensing image
Online_Linkage: N/A
Description:
Abstract:
This document describes a series of digital georectified images that were produced by the University of Texas at Austin Bureau of Economic Geology (Austin, TX). These georectified images provide coverage of the 1982 Texas Gulf of Mexico shoreline to approximately 5 km landward from Freeport to Sabine Pass. Galveston County, Texas funded the work as part of the U.S. Army Corps of Engineer's feasibility study activities for the Sabine Pass to Galveston Bay Shoreline Erosion Project. A georectified aerial photograph is a raster image of a vertical aerial photograph in which distortion has been removed and georeferencing information has been added. The images have a resolution of 800 ppi and are in false color infrared. They are projected in Universal Transverse Mercator (UTM) in meters on the North American Datum of 1983 (NAD83). The images were processed in ER Mapper format (.ers) and then converted to GeoTIFF.
Purpose:
The georectified images described in this document were created for the purpose of mapping shorelines and vegetation lines to be used in shoreline change analyses.
Time_Period_of_Content:
Time_Period_Information:
Multiple_Dates/Times:
Single_Date/Time:
Calendar_Date: 19820610
Time_of_Day: unknown
Single_Date/Time:
Calendar_Date: 19820709
Time_of_Day: unknown
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -95.355940
East_Bounding_Coordinate: -95.272085
North_Bounding_Coordinate: 28.988493
South_Bounding_Coordinate: 28.914669
Keywords:
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: Georectified aerial photograph
Theme_Keyword: rectified image
Place:
Place_Keyword: Texas
Place_Keyword: Gulf Coast
Place_Keyword: Galveston
Place_Keyword: Texas Gulf Coast
Place_Keyword: Gulf Of Mexico
Temporal:
Temporal_Keyword: 1982
Temporal_Keyword: 1980s
Access_Constraints: none
Use_Constraints: none
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jim Gibeaut
Contact_Organization: University of Texas Bureau of Economic Geology
Contact_Position: Research Associate
Contact_Address:
Address_Type: mailing address
Address: University Station Box X
City: Austin
State_or_Province: TX
Postal_Code: 78713-8924
Country: USA
Contact_Voice_Telephone: (512) 471-0344
Contact_Electronic_Mail_Address: jim.gibeaut@beg.utexas.edu
Browse_Graphic:
Data_Set_Credit: Rachel Waldinger, Jim Gibeaut, Bureau of Economic Geology
Native_Data_Set_Environment:
Microsoft Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcCatalog 8.1.0.642
Data_Quality_Information:
Attribute_Accuracy:
Completeness_Report:
The imagery provides complete coverage of the upper Texas Gulf of Mexico shoreline plus approximately 5 km landward from Freeport to Sabine Pass.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Georectified aerial photographs are based on USGS Digital Orthophoto Quads (DOQs):The DOQ horizontal positional accuracy and the assurance of that accuracy depend, in part, on the accuracy of the data inputs to the rectification process. These inputs consist of the digital elevation model (DEM), aerotriangulation control and methods, the photo source camera calibration, scanner calibration, and aerial photographs that meet National Aerial Photography Program (NAPP) standards. The vertical accuracy of all DEMs are equivalent to or better than a Level 1 or 2 DEM, with a root mean square error (RMSE) of no greater than 7.0 meters. Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards (NMAS) for 1:12,000-scale products. Aerial cameras have current certification from the USGS, National Mapping Division, Optical Science Laboratory. Test calibration scans are performed on all source photography scanners. Adjacent DOQs, when displayed together in a common planimetric coordinate system, may exhibit slight positional discrepancies across common DOQ boundaries. Linear features, such as streets, may not be continuous. These edge mismatches, however, still conform to positional horizontal accuracy within the NMAS. The Horizontal_Positional_Accuracy Value (see below) is an root mean square error (RMSE) of image positions to ground coordinates as determined by the orthorectification software used. (Source: Metadata for USGS DOQs, 1995) RMS error for Georectified images are less that 7 meters.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Texas General Land Office
Title: false-color infrared 1982 aerial photograph prints
Other_Citation_Details:
The photography was flown at a scale of 1:24,000. The prints are 9"x9". Each image was scanned at 800 dpi on a flat-bed scanner by the BEG.
Source_Scale_Denominator: 24,000
Type_of_Source_Media: aerial photograph print
Source_Time_Period_of_Content:
Time_Period_Information:
Multiple_Dates/Times:
Single_Date/Time:
Calendar_Date: 6/28/1982
Time_of_Day: unknown
Single_Date/Time:
Calendar_Date: 9/5/1982
Time_of_Day: unknown
Source_Currentness_Reference: ground condition
Source_Contribution: Texas General Land Office
Process_Step:
Process_Description:
Georectification of the aerial photographs involves the establishment of ground control points that link each image to its corresponding aerial coverage on a 1995 USGS digital orthophoto quarter quad (DOQQ). Points are chosen on the image that can be matched to points on the DOQQ. Road intersections and other cultural features are preferred as reference points rather than natural features. However, in many cases cultural features are lacking and features such as trees, shrubs, and the edges of water bodies are used. Where possible, points are evenly spaced across the image surface, with special emphasis on the edges of the image, and on areas near to the shoreline. The number of ground control points used for each image varies depending on how distorted the image is, and on the availability of suitable reference features. The average range is approximately 30 to 60 points per image. Once all the ground control points have been established, the image is rectified. Most images are rectified using a high-order polynomial algorithm, while some underwent a delaunay triangulation algorithm. Once the rectification was complete, the image was made semi-transparent and overlain on the DOQQ. In some areas a "double image" would occur, indicating that either more ground control points were needed, or that one or more existing ground control points had been placed incorrectly. In these cases, images were reprocessed to correct any remaining distortion.
Process_Date: Nov., Dec 2002, Jan. 2003
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Rachel Waldinger
Contact_Organization: Bureau of Economic Geology
Contact_Position: Research Scientist Associate
Contact_Address:
Address_Type: mailing address
Address: University station Box X
City: Austin
State_or_Province: TX
Postal_Code: 78713
Country: USA
Contact_Voice_Telephone: 9512) 472-5165
Contact_Electronic_Mail_Address: rachel.waldinger@mail.utexas.edu
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Pixel
Row_Count: 10033
Column_Count: 10023
Vertical_Count: 1
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 15
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.999600
Longitude_of_Central_Meridian: -93.000000
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: 0.800245
Ordinate_Resolution: 0.800245
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
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Band_1
Attribute:
Attribute_Label: ObjectID
Attribute:
Attribute_Label: Value
Attribute:
Attribute_Label: Red
Attribute:
Attribute_Label: Green
Attribute:
Attribute_Label: Blue
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: University of Texas at Austin Bureau of Economic Geology
Contact_Person: Jim Gibeaut
Contact_Position: Research Associate
Contact_Address:
Address_Type: mailing address
Address: University Station Box X
City: Austin
State_or_Province: TX
Postal_Code: 78713
Country: USA
Contact_Voice_Telephone: (512) 471-0344
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: TIFF
Transfer_Size: 95.908
Available_Time_Period:
Time_Period_Information:
Multiple_Dates/Times:
Single_Date/Time:
Calendar_Date: 6/10/82
Time_of_Day: unknown
Single_Date/Time:
Calendar_Date: 7/9/82
Time_of_Day: unknown
Metadata_Reference_Information:
Metadata_Date: 20030129
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Rachel Waldinger
Contact_Organization: University of Texas Bureau of Economic Geology
Contact_Position: Research Scientist Associate
Contact_Address:
Address_Type: mailing address
Address: University Station Box X
City: Austin
State_or_Province: TX
Postal_Code: 78713
Country: USA
Contact_Voice_Telephone: (512) 475-9551
Contact_Electronic_Mail_Address: rachel.waldinger@mail.utexas.edu
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
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Profile_Name: ESRI Metadata Profile
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Generated by mp version 2.7.3 on Wed Jan 29 10:56:41 2003