12K (3.75') Grid / Orthophoto Index for Louisiana, Geographic NAD83, LOSCO (2000) [quarterquads]

Metadata also available as - [Questions & Answers]

Metadata:


Identification_Information:

Citation:
Citation_Information:
Originator: Louisiana Oil Spill Coordinator's Office (LOSCO)
Publication_Date: 20000120
Title:
12K (3.75') Grid / Orthophoto Index for Louisiana, Geographic NAD83, LOSCO (2000) [quarterquads]
Description:
Abstract:
This is a polygon dataset depicting the bounds of a regular 3.75 minute grid in geographic coordinates, NAD83, for the state of Louisiana. This grid corresponds to the nominal footprint of standard USGS orthophotos of Louisiana. Each grid arc has been densified with intermediate vertices to allow the grid to be accurately projected to other coordinate systems. Each arc that forms a side of a 3.75' grid cell has been densified with intermediate vertices at a spacing corresponding to 100 meters.

The attributes of this dataset allow the determination the orthophoto associated with a polygon and its parent quadrangle name.

Purpose:
This grid depicts the nominal footprints of standard USGS orthophotos for the state of Louisiana and provides a guide to their names.
Supplemental_Information:
The metadata for this data set are encapsulated into several documents and graphics files. The metadata are not complete if you did not receive the following files along with the data set:

quarterquads.mtd - this metadata in mp (metadata parser) compatible ASCII text form
quarterquads.html - this metadata in HTML form
quarterquads_faq.html - this metadata presented as Questions and Answers
quarterquads.sgml - this metadata in SGML form
quarterquads1.gif - thumbnail graphic of data set
quarterquads2.gif - larger view of data set
quarterquads3.jpg - Screen grab illustrating registration of 12K grid with a
                      primary datum registration tic (the solid cross, NAD83)
                      for an orthophoto.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20000120
Currentness_Reference: date the index grid was completed
Status:
Progress: complete
Maintenance_and_Update_Frequency: none planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -94.0625
East_Bounding_Coordinate: -88.7500
North_Bounding_Coordinate: 33.0625
South_Bounding_Coordinate: 28.8125
Keywords:
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: quadrangle
Theme_Keyword: index
Theme_Keyword: orthophoto
Place:
Place_Keyword_Thesaurus: none
Place_Keyword: Louisiana
Access_Constraints: none
Use_Constraints:
These unaltered data may not be redistributed without all of the elements of the metadata listed in the Supplemental_Information section of this metadata document. It is recommended that third parties wishing to use these data obtain them from the Distributor listed in this metadata document.

If these data are altered or incorporated into another dataset, they are not to be redistributed without also: altering the name of the dataset, including a Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998) compliant metadata file that describes the dataset and reflects the alteration steps that makes the new dataset different from this one, and citing this dataset in the metadata as a source for the altered dataset using the source citation specified below.

If these digital data are used in the production of a report or in the compilation of a standalone printed map, then this dataset is to be cited in the report or on the map using the source citation specified below.

The following source citation is to be used when citing this dataset: LOSCO Environmental Baseline Inventory Dataset '12K (3.75') Grid / Orthophoto Index for Louisiana, Geographic NAD83, LOSCO (2000) [quarterquads]'

Users hereby agree to abide by the use and reproduction conditions specified above. By using the data described in these metadata, the user acknowledges that the terms and conditions of use have been read and that the user is bound by these criteria.

Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Louisiana Oil Spill Coordinator's Office
Contact_Person: David Gisclair
Contact_Position: Technical Assistance Program (TAP) Director
Contact_Address:
Address_Type: mailing address
Address: Louisiana Oil Spill Coordinator's Office
Address: Office of the Governor
Address: P.O. Box 94095
City: Baton Rouge
State_or_Province: LA
Postal_Code: 70804
Contact_Voice_Telephone: (225) 219-5800
Contact_Facsimile_Telephone: (225) 219-5802
Contact_Electronic_Mail_Address: <URL:mailto:tapgis@linknet.idt.net>
Browse_Graphic:
Browse_Graphic_File_Name: <URL:quarterquads1.gif>
Browse_Graphic_File_Description:
thumbnail graphic of data set. There are too many cells to resolve in the thumbnail. (1K)
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: <URL:quarterquads2.gif>
Browse_Graphic_File_Description: Larger view of data set (4K)
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: <URL:quarterquads3.jpg>
Browse_Graphic_File_Description:
Screen grab illustrating registration of 12K grid with a primary datum registration tic (the solid cross, NAD83) for an orthophoto. The dashed cross also visible is the registration tic for the secondary datum (NAD27). (13K)
Browse_Graphic_File_Type: JPEG
Data_Set_Credit:
LOSCO gratefully acknowledges Louisiana State University for providing the source data for production of this data set and DeWitt Braud for providing the information necessary to build this metadata.

Data_Quality_Information:

Logical_Consistency_Report:
The attributes of this data set have been rigorously checked as part of data processing at LSU. No topology errors are present. Because Louisiana shares two 7.5 minute quadrangles with Arkansas that have the same name as two 7.5 minute quadrangles on the interior of Louisiana, four qq_name values repeat.
Completeness_Report:
Because orthophotos have an an approximate 300 meter overedge, this grid provides a conservative estimate of the footprint of any individual orthophoto. The dataset includes all 3.75' tiles that intersect the state of Louisiana (and a small portion of Texas), providing an index to all of the digital orthophotos that are expected to be produced for LOSCO from the 1998 statewide LOSCO/USGS aerial photography project.
Lineage:
Process_Step:
Process_Description:
The grid was generated using MGE Grid Generation software and defined to be in geographic, NAD83 coordinates. The resultant .dgn file was converted to a shapefile and attributed.
Process_Date: 20000100
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: LSU Department of Geography and Anthropology
Contact_Person: Hampton Peele
Contact_Address:
Address_Type: mailing address
Address: Louisiana State University
City: Baton Rouge
State_or_Province: LA
Postal_Code: 70803
Contact_Voice_Telephone: (225)388-3455
Contact_Electronic_Mail_Address: hampton@lsu.edu

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: vector

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0.00000028
Longitude_Resolution: 0.00000028
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137
Denominator_of_Flattening_Ratio: 298.257

Entity_and_Attribute_Information:

Detailed_Description:
Entity_Type:
Entity_Type_Label: quarterquads.dbf
Entity_Type_Definition: attributes of 12K grid polygons
Entity_Type_Definition_Source: 3001, Inc.
Attribute:
Attribute_Label: qq_name
Attribute_Definition: textual name of the 'quarter quad,' a 3.75' cell
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The value is a concatenation of the textual name of the parent 7.5 quadrangle map name (in uppercase) and the quadrant identifier, NW, NE, SW or SE
Attribute:
Attribute_Label: qq_code
Attribute_Definition: alphanumeric code for the 'quarter quad,' a 3.75' cell
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The value is a concatenation of the USGS numeric code for the parent 7.5 quadrangle map name and quadrant identifier, NW, NE, SW or SE. There are no spaces in the value and a period separates the numeric part from quadrant identifier part.

The seven digit USGS numeric code is derived from the latitude and longitude of the southeast corner of the one degree block of which the 7.5' quadrangle is a part and a one-of-64 identifier for each 7.5' tile within that block. The one-of-64 tile numbering scheme is for the 8 by 8 matrix of 7.5 minute tiles that compose a one degree block. The tile numbering scheme begins with 01 in the northwest corner of the block, proceeds left to right across the top row and each subsequent row, finally ending with the number 64 at the southeast corner of the block.

Attribute:
Attribute_Label: qq_number
Attribute_Definition: numeric code for an individual 'quarter quad,' a 3.75' cell
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The value is derived by appending a numeric quadrant identifier to the 7 digit USGS numeric code for the parent 7.5 quadrangle map name. The numeric quadrant identifiers are:
1 = NW
2 = NE
3 = SE
4 = SW
Attribute:
Attribute_Label: lagis_name
Attribute_Definition:
textual name of parent 7.5 minute quadrangle of which the 3.75 minute tile is a part
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
An uppercase version of the names as tabulated at: <URL:http://mapping.usgs.gov/mac/maplists/>. Note that both Gardner and Empire occur as map names in interior Louisiana as well on the border with Arkansas.
Attribute:
Attribute_Label: lagisqd_no
Attribute_Definition:
USGS style numeric code for parent 7.5 minute quadrangle of which the 3.75 minute tile is a part
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The seven digit USGS style numeric code is derived from the latitude and longitude of the southeast corner of the one degree block of which the 7.5' quadrangle is a part and a one-of-64 identifier for each 7.5' tile within that block. The one-of-64 tile numbering scheme is for the 8 by 8 matrix of 7.5 minute tiles that compose a one degree block. The tile numbering scheme begins with 01 in the northwest corner of the block, proceeds left to right across the top row and each subsequent row, finally ending with the number 64 at the southeast corner of the block. The value is exactly equal to the usgs_no except when there is no usgs_no because there is no named 7.5 minute map for that area.
Attribute:
Attribute_Label: area_sqm
Attribute_Definition: area of 3.75 tile in square meters
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 40439411
Range_Domain_Maximum: 42343208
Attribute_Units_of_Measure: square meters
Attribute:
Attribute_Label: perim_m
Attribute_Definition: perimeter of 3.75' tile in meters
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 25530
Range_Domain_Maximum: 26081
Attribute_Units_of_Measure: meters
Attribute:
Attribute_Label: area_ac
Attribute_Definition: area of 3.75 minute tile in acres
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 9993
Range_Domain_Maximum: 10463
Attribute_Units_of_Measure: acres
Attribute:
Attribute_Label: usgsalpha
Attribute_Definition: USGS alphanumeric code for the 7.5' parent cell, if it has one
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The seven character alphanumeric USGS code is derived from the latitude and longitude of the southeast corner of the one degree block of which the 7.5' quadrangle is a part and a one-of-64 identifier for each 7.5' tile within that block. The one-of-64 tile identification scheme is for the 8 by 8 matrix of 7.5 minute tiles that compose a one degree block. The tile identification scheme begins from the SE corner of the one degree block. Rows are lettered bottom to top beginning with A and ending with H. Columns are numbered east to west beginning with 1 and ending with 8. Thus, the the 7.5' tile at the SE corner of the one degree block is A1 and the cell at the northwest corner of the one degree block is H8. The alphanumeric code is composed of the lat/long part followed by the one-of-64 part of the code.
Enumerated_Domain:
Enumerated_Domain_Value: no value, a blank
Enumerated_Domain_Value_Definition:
There is no named USGS 7.5 minute map whose area encompasses this cell
Attribute:
Attribute_Label: usgs_no
Attribute_Definition: USGS numeric code for the 7.5' parent cell, if it has one
Attribute_Definition_Source: LSU Department of Geography and Anthropology
Attribute_Domain_Values:
Unrepresentable_Domain:
The seven digit USGS numeric code is derived from the latitude and longitude of the southeast corner of the one degree block of which the 7.5' quadrangle is a part and a one-of-64 identifier for each 7.5' tile within that block. The one-of-64 tile numbering scheme is for the 8 by 8 matrix of 7.5 minute tiles that compose a one degree block. The tile numbering scheme begins with 01 in the northwest corner of the block, proceeds left to right across the top row and each subsequent row, finally ending with the number 64 at the southeast corner of the block. The numeric code is composed of the lat/long part followed by the one-of-64 part of the code.
Enumerated_Domain:
Enumerated_Domain_Value: 0
Enumerated_Domain_Value_Definition:
There is no named USGS 7.5 minute map whose area encompasses this cell

Distribution_Information:

Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Louisiana Oil Spill Coordinator's Office
Contact_Person: David Gisclair
Contact_Position: Technical Assistance Program (TAP) Director
Contact_Address:
Address_Type: mailing address
Address: Louisiana Oil Spill Coordinator's Office
Address: Office of the Governor
Address: P.O. Box 94095
City: Baton Rouge
State_or_Province: LA
Postal_Code: 70804
Contact_Voice_Telephone: (225) 219-5800
Contact_Facsimile_Telephone: (225) 219-5802
Contact_Electronic_Mail_Address: <URL:mailto:tapgis@linknet.idt.net>
Resource_Description: quarterquads
Distribution_Liability:
The data herein, including but not limited to geographic data, tabular data, analytical data, electronic data structures or files, are provided "as is" without warranty of any kind, either expressed or implied, or statutory, including, but not limited to, the implied warranties or merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the data is assumed by the user. No guarantee of accuracy is granted, nor is any responsibility for reliance thereon assumed. In no event shall the Louisiana Oil Spill Coordinator's Office (LOSCO) be liable for direct, indirect, incidental, consequential or special damages of any kind, including, but not limited to, loss of anticipated profits or benefits arising out of use of or reliance on the data. The LOSCO does not accept liability for any damages or misrepresentation caused by inaccuracies in the data or as a result of changes to the data caused by system transfers or other transformations or conversions, nor is there responsibility assumed to maintain the data in any manner or form.

These data have been developed from the best available sources. Although efforts have been made to ensure that the data are accurate and reliable, errors and variable conditions originating from physical sources used to develop the data may be reflected in the data supplied. Users must be aware of these conditions and bear responsibility for the appropriate use of the information with respect to possible errors, scale, resolution, rectification, positional accuracy, development methodology, time period, environmental and climatic conditions and other circumstances specific to these data. The user is responsible for understanding the accuracy limitations of the data provided herein. The burden for determining fitness for use lies entirely with the user. The user should refer to the accompanying metadata notes for a description of the data and data development procedures.

Although these data have been processed successfully on computers at the LOSCO, no guarantee, expressed or implied, is made by LOSCO regarding the use of these data on any other system, nor does the act of distribution constitute or imply any such warranty. Distribution of these data is intended for information purposes and should not be considered authoritative for navigational, engineering, legal and other site-specific uses.


Metadata_Reference_Information:

Metadata_Date: 20000121
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: 3001, Inc.
Contact_Person: Hugh Phillips
Contact_Position: GIS Analyst
Contact_Address:
Address_Type: mailing and physical address
Address: 3655 SW 2nd Ave., Suite 3C
City: Gainesville
State_or_Province: FL
Postal_Code: 32607
Contact_Voice_Telephone: (352) 379-3001
Contact_Facsimile_Telephone: (352) 377-4234
Contact_Electronic_Mail_Address: <URL:mailto:hphillips@gnv.3001data.cpm>
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998

Generated by mp version 2.4.38 on Fri Jan 21 14:40:48 2000