Preliminary Landform Subdivisions of Pennsylvania, 1998
Metadata:
Identification_Information:
Citation:
Citation_Information:
Originator: Pennsylvania Bureau of Topographic and Geologic Survey, Department of
Conservation and Natural Resources
Publication_Date: 1998
Title: Preliminary Landform Subdivisions of Pennsylvania, 1998
Edition: 1.0
Geospatial_Data_Presentation_Form: Map
Publication_Information:
Publication_Place: Harrisburg, Pennsylvania
Publisher: Pennsylvania Bureau of Topographic and Geologic Survey
Description:
Abstract:
The land surface of Pennsylvania is anything but flat and horizontal. The surface
comprises complex arrangements of differences in elevation above mean sea level. The
spatial arrangement of these elevation differences comprises topography. Topography
that has describable uniformity throughout some areal dimension is termed a landform.
Landforms can be classified, boundaries can be drawn, and a map can be created. A
preliminary landform map was compiled at approximately 1:605,500 scale. The map has
four levels of landform subdivision: province, section, region, and district. These units
range in size from many hundreds of square miles (province) to less than 200 square
miles (district). The greatest topographic similarity for a given landform unit occurs in
the smallest subdivision (district). The greatest topographic dissimilarity for a given
landform unit occurs in the largest subdivision (province).
The landform map was digitized using ARC/INFO software. Polygon attributes include
name of physiographic province, section, district, and area, and the numerical designation
of the landform unit. Arcs were attributed according to whether they form the boundary
of one or more of the following: province, section, region, district, or state.
These data sets are preliminary and will be superseded in 1999 by more detailed data sets
prepared from 1:50,000-scale compilation maps having five levels of landform
subdivision.
Purpose:
It is anticipated that these data sets will be of use for a variety of statewide or regional
GIS applications, including ecosystem management, conservation, and land use planning
and development.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1998
Currentness_Reference: 1998
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -80.5196
East_Bounding_Coordinate: -74.6899
North_Bounding_Coordinate: 42.2698
South_Bounding_Coordinate: 39.7196
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Landforms
Theme_Keyword: Landform province
Theme_Keyword: Landform section
Theme_Keyword: Landform region
Theme_Keyword: Landform district
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Pennsylvania
Access_Constraints: None
Use_Constraints:
The data for the preliminary landform subdivisions may be used provided that credit for the
original (unaltered) data sets is given to the Pennsylvania Bureau of Topographic and
Geologic Survey, Department of Conservation and Natural Resources. Users shall clearly
indicate the source of the data. Users who modify the data in any way are obligated to
describe the types of modifications they have made, including modifications to hard-copy
maps. Users are not to misrepresent Pennsylvania Bureau of Topographic and Geologic
Survey (PaGS) data sets, nor to imply that changes they (users) have made were approved
by the PaGS.
The data set is not meant for site-specific analysis or for use at finer (i.e., larger, more
detailed) scales. Users are not to misrepresent the data sets by presenting it at scales for
which it is not intended, nor to imply that presentation at such scales is approved by the
PaGS.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Christine E. Miles
Contact_Organization: Pennsylvania Bureau of Topographic and Geologic Survey,
Department of Conservation and Natural Resources
Contact_Address:
Address_Type: Mailing address
Address: Bureau of Topographic and Geologic Survey, P. O. Box 8453
City: Harrisburg
State_or_Province: Pennsylvania
Postal_Code: 17105-8453
Country: USA
Contact_Voice_Telephone: 717-783-5812
Contact_TDD/TTY_Telephone: 1-800-654-5984 (TDD) Pa. AT&T relay service
Contact_Facsimile_Telephone: 717-783-7267
Contact_Electronic_Mail_Address: miles.christine@dcnr.state.pa.us
Hours_of_Service: 8:00 a.m.-5:00 p.m., Monday-Friday
Data_Set_Credit:
Landform classifications and subdivisions by W. D. Sevon, Pennsylvania Bureau of
Topographic and Geologic Survey (PaGS). Digital work and GIS processing of data sets
by John G. Kuchinski (PaGS) and Christine E. Miles (PaGS). Documentation by W. D.
Sevon (first paragraph of abstract) and Christine E. Miles (remainder).
Native_Data_Set_Environment:
Dell OptiPlex GXpro 200 workstation running Windows NT version 4.0 and NT
ARC/INFO version 7.1.2.
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Attributes were reviewed by staff of the PaGS by (1) comparing check plots with the
source maps; (2) visually checking attributes on a display of the map data on a computer
workstation; (3) checking printouts of the attributes; and (4) running a macro to ensure
correctness and consistency of polygon attributes. Based on these reviews, the attributes
are believed to be accurate.
Logical_Consistency_Report:
Complete chain-node topology is present. The data set was checked for polygon closure,
erroneous or duplicate arcs, incorrect intersections, overshoots and undershoots, label
errors, node errors, and appropriate fuzzy tolerances.
Completeness_Report:
The data set represents a preliminary compilation of the landform units of Pennsylvania.
A more detailed, final version of the landform subdivisions is being prepared and should be
available in digital form in 1999. On the final map, almost all linework will be revised,
accuracy will be enhanced because the map will be digitized from a much larger scale
compilation, numerous subdivisions will be added that are not present on the preliminary
version, and names of some landform units will be changed.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The base map on which the 1998 preliminary landform map was compiled was a
digitally generated plot on paper at approximately 1:605,500 scale showing county
boundaries and topographic contours derived from the U.S. Geological Survey (USGS)
1:250,000-scale digital elevation models for Pennsylvania (30-meter interval). The
landform boundaries were positioned in relation to the topographic contour lines on
the base map. The accuracy of the data set derived from this compilation is unknown,
but it certainly does not exceed, and probably is less than, the accuracy of the the base
map.
Process_Step:
Process_Description:
A paper plot showing county boundaries and topographic contours in Pennsylvania was
provided to W. D. Sevon by the Pennsylvania Bureau of Forestry, Department of
Conservation and Natural Resources. The topographic contours on the base map are
derived from the USGS 1:250,000-scale digital-elevation models for Pennsylvania and
have a contour interval of 30 meters. The landform subdivisions had been initially
compiled by Sevon on 1:50,000-scale standard series USGS county topographic maps for
Pennsylvania. To compile the regional preliminary landform map, Sevon transferred the
landform boundaries to the 1:605,500 paper base map by visual inspection. Latitude and
longitude control points were added to the map, and it was scanned, converted to a grid
using ARC/INFO software, georeferenced, and projected to the Lambert projection used
by the Bureau of Forestry on the original base map provided. The parameters for that
projection are as follows:
Projection: Lambert
Datum: NAD83
Units: meters
Spheroid: GRS1980
Parameters:
40 15 0.000 /*1st standard parallel
41 30 0.000 /*2nd standard parallel
-78 0 0.000 /*central meridian
39 0 0.000 /*latitude of projection's origin
0.00000 /*false easting (meters)
0.00000 /*false northing (meters)
Using the projected grid as a background image, the arcs were digitized and attributed,
and polygon labels were added and attributed with a number derived from the
alphanumeric labels that identified each landform subdivision on the compilation map. A
separate data set was prepared for annotation, consisting of (1) the alphanumeric
designations of the landform units, and (2) leader lines drawn as arcs to the polygons that
are too small in area to contain labels.
Following the digitizing and attributing of the polygons and arcs, various check plots
were prepared and proofread in order to verify the locational accuracy of the lines and to
check for errors in arc attributes and in labels of landform units. Additional checks were
made on the computer workstation for label and attribute errors.
A script was prepared in Arc Macro Language (AML) to ensure correctness and
consistency of polygon attributes. Using the script, the item for the landform number was
selected for each polygon, and the correct attributes for PROVINCE, SECTION,
REGION, and DISTRICT were calculated based on the landform number.
After all corrections were made, the data sets were projected to new data sets in a
geographic coordinate system (units in decimal degrees). The latter data sets were
exported as ARC/INFO export files (landform98.e00 and landanno98.e00).
Process_Date: 1998
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and Vector_Object Information:
SDTS_Terms_Description:
STDS_Point_and_Vector_Object_Type: Node (in landform98 data set)
Point_and_Vector_Object_Count: 357
SDTS_Terms_Description:
STDS_Point_and_Vector_Object_Type: Complete chain (in landform98 data set)
Point_and_Vector_Object_Count: 498
SDTS_Terms_Description:
STDS_Point_and_Vector_Object_Type: GT-polygon composed of chains (in
landform98 data set)
Point_and_Vector_Object_Count: 208
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: Unknown
Longitude_Resolution: Unknown
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1927
Ellipsoid_Name: Clarke 1866
Semi-major_Axis: 6378206.4
Denominator_of_Flattening_Ratio: 294.98
Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:
The entity type is a landform unit. There are four levels of subdivision: province,
section, region, and district.
The polygon and line (arc) attribute items for the entity type of geologic unit are in
typical ARC/INFO feature class format. User-defined polygon attributes (in table
landform98.pat) include the names of the province, section, region, and district, and the
number assigned to the landform unit. User-defined arc attributes (in table
landform98.aat) include designation of each line as one or more of the following
boundaries: province, section, region, district, and state.
Distribution_Information:
Distribution_Liability:
Not for commercial resale.
These data files and documentation are provided "as is," and the User assumes the entire
risk as to their quality and performance.
The Commonwealth of Pennsylvania makes no guarantee or warranty concerning the
accuracy of information contained in the geographic data or accompanying documentation.
The Commonwealth of Pennsylvania further makes no warrantees, either expressed or
implied, as to any other matter whatsoever, including, without limitation, the completeness
or condition of the product, or its fitness for any particular purpose. The burden for
determining fitness for use lies entirely with the User.
Although these data have been processed successfully on a computer system at the Bureau
of Topographic and Geologic Survey, the Commonwealth of Pennsylvania makes no
warranty, expressed or implied, regarding the use of the data files or accompanying
documentation on any other computer system, nor does the act of distribution constitute any
such warranty.
The User shall save the Commonwealth of Pennsylvania harmless from any suits, claims, or
actions arising out of the use of or any defect in the data files or accompanying
documentation.
The Commonwealth of Pennsylvania assumes no legal liability for the accuracy,
completeness, or usefulness of the data files and accompanying documentation. In no event
shall the Commonwealth of Pennsylvania have any liability whatsoever for payment of
any consequential, incidental, indirect, special, or tort damages of any kind, including, but
not limited to, any loss of profits arising out of use of or reliance on the geographic data.
Metadata_Reference_Information:
Metadata_Date: 19981207
Metadata_Review_Date: 19981207
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Christine E. Miles
Contact_Organization: Pennsylvania Bureau of Topographic and Geologic Survey,
Department of Conservation and Natural Resources
Contact_Address:
Address_Type: Mailing address
Address: Bureau of Topographic and Geologic Survey, P. O. Box 8453
City: Harrisburg
State_or_Province: Pennsylvania
Postal_Code: 17105-8453
Country: USA
Contact_Voice_Telephone: 717-783-5812
Contact_TDD/TTY_Telephone: 1-800-654-5984 (TDD) Pa. AT&T relay service
Contact_Facsimile_Telephone: 717-783-7267
Contact_Electronic_Mail_Address: miles.christine@dcnr.state.pa.us
Hours_of_Service: 8:00 a.m.-5:00 p.m., Monday-Friday
Metadata_Standard_Name: Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: 19940608