Pennsylvania Spatial Data Access

Abstract:

This geology shapefile covers the entire Susquehanna River Basin (2006 boundary).  It represents the merging of three state (NY, PA, MD) bedrock geology spatial datasets in order to provide basic rock types of the Susquehanna River Basin.  The dominant formation lithology that appears in the attribute table were grouped into 19 general rock types, such as sandstone, shale, schist, limestone, dolomite, etc.  These rock types are also categorized by hydrostratigraphic terrain.  The hydrostratigraphic terrain helps to identify the way in which water flows over or through these rocks.

Purpose:

Dataset developed to fit the needs of the Susquehanna River Basin Commission and is intended for educational display purposes only. Created to obtain lithologic similarity across state lines through basic rock types.

Supplemental_Information:

Largest scale to be used when viewing- 1:100,000

Currentness_Reference:

publication date

Use_Constraints:

For educational/demostration purposes only.  The Originator, Publisher, and Distributor exclude any and all implied warranties and make no warranty or representation with respect to the data files or accompanying documentation, including quality, performance, merchantability or fitness for a particular purpose. These data files and documentation are provided "as is" and the User assumes the entire risk as to their quality and performance.

These data are not to be redistributed for commercial profit.  Reproduction or redistribution of this digital dataset without permission of the Originator/Publisher is expressly forbidden.  The Originator and Publisher should be clearly cited in any product derived from this data.  Any modifications to this data must be described in any digital or hardcopy product derived from this data.

Address:

1721 North Front Street

Data_Set_Credit:

Rock Type Classifications, Jeff Howe, Hydrogeologist, SRBC; 
Rock Type Classifications, Robert Edwards, Special Projects Manager, SRBC; 
Hydrostratigraphic Classifications, Robert Pody, Hydrogeologist, SRBC.

Attribute_Accuracy_Report:

No systematic analysis has been performed.  Attribute accuracy corresponds to the accuracy of the source materials.

Logical_Consistency_Report:

New York geology is from the NYS Museum, NYS Geologic Survey from 1999.  PA geology is from PA DCNR from 2001 and MD geology is from USGS from 1992.

Completeness_Report:

Dataset is complete for the Susquehanna River Basin.  This dataset was not modified at the state lines to achieve seamless data.

Horizontal_Positional_Accuracy_Report:

Positional accuracy corresponds to the accuracy of the source materials.

Source_Contribution:

Geologic Formations of Pennsylvania

Source_Contribution:

Geologic Formations of New York

Source_Contribution:

Geologic Formations of Maryland

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Source_Contribution:

Reference for correlation of lithologies between New York, Pennsylvania, and Maryland; SRBC, April 2004

Process_Description:

The New York and Pennsylvania bedrock geologic layers and the Maryland generalized geology layer were obtained from the respective state agencies and renamed bedrx_ny, bedrx_pa, and geology_md.  For information on the creation of these files, please see appropriate metadata.  The datasets were converted into shapefiles and merged together using ArcMap Geoprocessing Wizard.  Select attributes were maintained from bedrx_pa.shp for the PA portion of the dataset and SRBC staff further populated attribute information for New York and Maryland (described in the next process step).

Process_Description:

Jeff Howe and Robert E. Edwards of the SRBC researched the lithologies of each formation falling within the Basin.  A generalized rock type attribute field was assigned to each formation and lith1, lith2, lith3 attribute fields were updated where possible.

Process_Description:

Robert Pody of the SRBC added a "hydrostratigraphic terrain" field that desribes how water flows over or through these general rock types.

Process_Description:

This dataset was modified to fit the 2006 version of the Susquehanna River Basin boundary.  Due to errors at the state lines and an apparent shift of the New York data, the file divided into a New York shapefile and a PA/MD shapefile.  

The New York shapefile was moved to match the basin boundary which fixed the shift.  The file was then unioned to the Basin boundary to fill in empty spaces around the perimeter.  The Basin boundary part was then exploded to eliminate the multi-part feature.  The PA/MD part of the Basin was deleted.  All remaining slivers around the perimeter of NY were given appropriate attributes.  The NY shapefile was then dissolved based on the "NAME" field and clipped to a New York State extent.

Process_Description:

The PA/MD shapefile was updated to match the 2006 version of the Basin boundary.  Added polygons were given apprpriate attributes.  The PA/MD shapefile was edited to match the NY shapefile at the state line and the MD/PA state line was updated.  The PA/MD shapefile was dissolved using the "NAME" field.

Process_Description:

The attribute tables were updated to match the original format which lost during the 'Dissolve' processes.  bedrxNY_New.shp was appended to bedrock_ClipDis.shp.  bedrock_ClipDis.shp was then clipped to the 2006 Basin boundary.  Area, Perimeter, and SQM fields were updated.  Files used in the creation of the 2006 bedrock shapefile are stored in the SRBC GIS library disk #1236.

Process_Description:

Dataset copied.

Attribute_Definition:

Internal feature number.

Attribute_Definition_Source:

ESRI

Attribute_Definition:

Feature geometry.

Attribute_Definition_Source:

ESRI

Attribute_Definition:

The name of the geologic unit.

Attribute_Definition_Source:

DCNR, 2001; USGS, 1992; NYS Museum, 1999

Attribute_Definition:

Area in square meters

Attribute_Definition_Source:

SRBC

Attribute_Definition:

Perimeter in meters

Attribute_Definition_Source:

SRBC

Attribute_Definition:

Area in square miles

Attribute_Definition_Source:

SRBC

Attribute_Definition:

The symbol used to label the unit on the respective State Geologic Map

Attribute_Definition_Source:

DCNR, 2001; USGS, 1992; NYS Museum, 1999

Attribute_Definition:

Age of the geologic unit

Attribute_Definition_Source:

DCNR, 2001

Attribute_Definition:

The dominant lithology, volumetrically, in the rock unit.

Attribute_Definition_Source:

DCNR, 2001; SRBC

Attribute_Definition:

Secondmost dominant lithology in the rock unit

Attribute_Definition_Source:

DCNR, 2001; SRBC

Attribute_Definition:

Other major lithologies in the rock unit

Attribute_Definition_Source:

DCNR, 2001; SRBC

Attribute_Definition:

Dominant rock type

Attribute_Definition_Source:

SRBC