Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey - Florida Integrated Sciences Center Publication_Date: 2007 Title: Overwash_Zone Geospatial_Data_Presentation_Form: vector digital data Description: Abstract: A representation of the overwash zones to be found on Assateague Island, divided into active and inactive overwash zones. Active overwash zones are areas that are frequently flooded by high water and ocean waves generated by storms. They are typically low lying with sparse vegetation and composed of sand with a concentrated layer of shell at the surface. Inactive overwash zones are areas that were historically overwashed by storm surge, such as during the 1962 Ash Wednesday Storm, or created by overwash such as the flats that widened the north end of the island during the 1998 storms. These areas are not flooded frequently by high water and ocean waves, but are still vulnerable to flooding from extreme storms. The former overwash sand is commonly rewarked into low dunes and can be densely vegetated with low woody plants. Inactive overwash zones typically grade landward into marshes. This shapefile was developed using DOQ's and EAARL DEM. In unison with several others, the shapefile gives a complete geomorphological representation of Assateague Island National Seashore and Chincoteague National Wildlife Refuge. Purpose: To geomorphologically classify the overwash zones of Assateague Island, and so provide a viable land management tool for the park services at Assateague Island National Seashore. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1989 Ending_Date: 2004 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -75.407992 East_Bounding_Coordinate: -75.092933 North_Bounding_Coordinate: 38.324364 South_Bounding_Coordinate: 37.865225 Keywords: Theme: Theme_Keyword: Geology Theme_Keyword: Barrier Island Theme_Keyword: National Park Theme_Keyword: Wildlife Refuge Theme_Keyword: Overwash Zone Place: Place_Keyword: Assateague Island Place_Keyword: Chincoteague Place_Keyword: United States Place_Keyword: Maryland Place_Keyword: Virginia Access_Constraints: Any use of these data signifies a user's agreement to comprehension and compliance of the USGS Standard Disclaimer. Ensure all portions of metadata are read and clearly understood before using these data in order to protect both user and USGS interests. See section 6.3 Distribution Liability. Use_Constraints: Although the USGS is making these data available to others who may find the data of value, USGS does not warrant, endorse, or recommend the use of these data for any given purpose. The user assumes the entire risk related to the use of these data. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Dr. Robert A. Morton Contact_Organization: United States Geological Survey - Florida Integrated Sciences Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: Saint Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: 9 AM - 4 PM Contact_Instructions: Contact the USGS. Data_Set_Credit: Robert A. Morton, Jeremy E. Bracone, Brian Cooke Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.2.1350 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Both 'Shape_Length' and 'Shape_Area" attributes were inherently generated and calculated by the ESRI ArcGIS Personal Geodatabase these layers were edited in. They should be accurate to 0.01 meters. Logical_Consistency_Report: Due to these data being created from multiple sources including aerial photography from 1999 and 2003, elevation data from lidar surveys, older NPS classification maps and shapefiles, and historical photographs, some areas will be more accurate than others. While most of the data is referenced to 0.25 meter resolution aerial photography taken in 2003 and EAARL lidar surveys taken in 2003 and 2004, some areas were not updated from lower resolution aerial photography taken in 1999. Completeness_Report: This shapefile is part of a 17 layer series and only contains areas classified as accretion mounds. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The sources of data used to delineate the map unit boundaries were 1999 National Park Service aerial photographs (0.76 m resolution), 2003 National Park Service aerial photographs (0.25 m resolution), 2003 and 2004 joint NASA/USGS lidar elevation surveys (1 m horizontal resolution), and a vegetation map provided by the National Park Service (10 m resolution). Most of the map boundaries of the classification units were referenced to the 2003 aerial photographs. Lineage: Process_Step: Process_Description: Initial classification of Assateague Island was made by Dr. Robert A. Morton and Brian Cooke using historical photography, 1999 and 2003 aerial photography, and published National Park Service classifications of Assateague Island. Layers were roughly drawn in a mosaic-like manner such that barrier core was the background layer and all other layers were drawn on top of it. Process_Date: 2004-2005 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Robert A. Morton Contact_Organization: United States Geological Survey - Florida Integrated Sciences Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: Saint Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: 9 AM - 4 PM, M-F Contact_Instructions: Contact the USGS. Process_Step: Process_Description: Previous process resulted in overlapping areas, layers with gaps between them, and multiple shapes to create a single area. There were many mistakes, mis-referenced layers, and 2003 aerial photography became available. All data layers were imported into a Personal Geodatabase. A topology that included all the layers making up the Assateague Island geomorphic map was created and an extensive rule set was generated to enable the use of ArcGIS topology tools to find and fix overlapping regions and other problems. After all overlaps were addressed, layers were referenced to more recent data and errors in the original classification were addressed. Process_Date: March 2007 - July 2007 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jeremy E. Bracone Contact_Organization: ETI Professionals Inc. / U.S. Geological Survey - Florida Integrated Sciences Center Contact_Position: GIS and Remote Sensing Analyst Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: Saint Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: 9 AM - 4 PM, M-F Contact_Instructions: Contact the USGS. Process_Step: Process_Description: Extraneous attributes were removed and all layers were exported from the Personal Geodatabase. Process_Date: July 2007 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jeremy E. Bracone Contact_Organization: ETI Professionals Inc. / U.S. Geological Survey - Florida Integrated Sciences Center Contact_Position: GIS and Remote Sensing Analyst Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: Saint Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: 9 AM - 4 PM, M-F Contact_Instructions: Contact the USGS. Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: G-polygon Point_and_Vector_Object_Count: 166 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 18 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -75.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.000000 Ordinate_Resolution: 0.000000 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: Overwash_Zone Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: Shape_Leng Attribute_Definition: The perimeter of feature in internal units. Attribute_Definition_Source: ESRI - Automatically generated and updated in the personal geodatabase this shapefile was exported from. Attribute_Value_Accuracy_Information: Attribute_Value_Accuracy: 0.01 Attribute: Attribute_Label: Shape_Area Attribute_Definition: Area of feature in internal units squared. Attribute_Definition_Source: ESRI - Automatically generated and updated in the personal geodatabase this shapefile was exported from. Attribute_Domain_Values: Unrepresentable_Domain: Positive real numbers that are automatically generated. Attribute_Value_Accuracy_Information: Attribute_Value_Accuracy: 0.01 Attribute: Attribute_Label: TYPE Distribution_Information: Resource_Description: Downloadable Data Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Transfer_Size: 0.310 Metadata_Reference_Information: Metadata_Date: 20070820 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - Florida Integrated Sciences Center Contact_Person: Jeremy E. Bracone (ETI Professional Inc.) Contact_Position: GIS and Remote Sensing Analyst Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: Saint Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-803-8747 Hours_of_Service: 9 AM - 4 PM, M-F Contact_Instructions: Contact the USGS. Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Extensions: Online_Linkage: http://www.esri.com/metadata/esriprof80.html Profile_Name: ESRI Metadata Profile