Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2002 Title: elspremitch Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: 01-0444 Publication_Information: Publisher: U.S. Geological Survey Online_Linkage: http://mitchntsl.cr.usgs.gov Larger_Work_Citation: Citation_Information: Originator: Anthony J. Crone Originator: Rex L. Baum Originator: David J. Lidke Originator: Damon N.D. Sather Originator: Lee-Ann Bradley Originator: Arthur C. Tarr Title: Landslides Induced by Hurricane Mitch in El Salvador-An Inventory and Descriptions of Selected Features Geospatial_Data_Presentation_Form: map Description: Abstract: This cover contains the outlines of selected landslides and debris flows that occurred prior to Hurricane Mitch in the areas where hurricane-induced landslides were mapped. The landslides and debris flows shown in this coverage were mapped using 1:40,00-scale and 1:15,000-scale black-and-white aerial photographs. Much of the photography was taken a few months after the storm, but additional photography was taken in late 2000. The photographs were visually examined using 4-X mirror stereoscopes, and the landslides were plotted by hand on mylar overlays that were registered to topographic maps. The landslides were plotted on 1:25,000-scale maps where these high-quality maps were available; for other parts of the country, the landslides were plotted on 1:50,000-scale maps. The plotted landslides were then manually digitized and registered to digital raster graphic (DRG) images of 1:50,000-scale topographic maps. Some of the areas in this coverage are composites of parts of two or more 12:50,000-scale quadrangles. To produce these composites, the edges of adjoining quadrangles had to be digitally adjusted in ArcInfo to assure continuity between adjacent maps. These adjustments were also necessary to resolve differences in the resolution between 1:50,000-scale and 1:25,000-scale topographic maps. After these adjustments, the areas of each plate were cut from merged DRGs and the digital landslides were then plotted on the DRG images of the map areas. The cover portrays the shapes, relative location, and size of pre-hurricane landslides and the associated downslope deposits. For those features that were originally mapped on 1:25,000-scale topographic maps, we estimate that their locations are accurate to within less than 100 m and probably to within 50m. For features that were originally mapped on 1:50,000-scale topographic maps, their locations are probably accurate to within 100-200m. Purpose: The coverage shows the distribution of pre-hurricane slope failures and the associated deposits selected parts of El Salvador. The cover included maps of these features in widely separated parts of the country. The maps provide an inventory of these features and also contain a few recent landslides that predate the hurricane. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 12/2001 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.858421 East_Bounding_Coordinate: -88.527321 North_Bounding_Coordinate: 14.066360 South_Bounding_Coordinate: 13.560819 Keywords: Theme: Theme_Keyword: landslides Theme_Keyword: Hurricane Mitch Theme_Keyword: debris flows Theme_Keyword: earth flows Theme_Keyword: inventory Theme_Keyword: rainfall Theme_Keyword: pre-Hurricane Mitch Place: Place_Keyword: El Salvador Place_Keyword: San Ignacio Place_Keyword: Tejutla Place_Keyword: Santa Ana Place_Keyword: Ahuachapan Place_Keyword: Berlin Place_Keyword: San Miguel Place_Keyword: Embalse Cerron Grande Place_Keyword: Embalse 15 de Septiembre Temporal: Temporal_Keyword: October 1998 Temporal_Keyword: November 1998 Access_Constraints: No access constraints Use_Constraints: No user constraints Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Anthony J. Crone Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing address Address: U.S. Geological Survey, MS 966, Box 25046 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: 303 273-8591 Contact_Facsimile_Telephone: 303 273-8600 Contact_Electronic_Mail_Address: crone@usgs.gov Hours_of_Service: 08:00-16:30 Mountain Time Contact_Instructions: Physical Address: 1711 Illinois St., Golden, CO 80403 Native_Data_Set_Environment: Microsoft Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcCatalog 8.1.1.649 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Attribute accuracy was assured by visually comparing compilation copy with plotted map in which the landslide styles were color coded. Logical_Consistency_Report: Registration accuracy was checked by inspecting plots of the data and graticule overlaid on a Digital Raster Graphic (DRG) of the base map. Topological consistency was checked by assuring that all data polygons had one label point. Completeness_Report: Completeness was assured by visually inspecting the compilation map overlaid on the plotted map looking for missing polygons. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: For those landslides that were originally mapped on 1:25,000-scale topographic maps, we estimate that their locations are accurate to within less than 100 m and probably to within 50m. For features that were originally mapped on 1:50,000-scale topographic maps, their locations are probably accurate to within 100-200m. Lineage: Source_Information: Source_Scale_Denominator: 1:15,000 and 1:40,000 Type_of_Source_Media: aerial photographs Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 12/1998 Ending_Date: 12/2000 Source_Currentness_Reference: ground condition Process_Step: Process_Description: Aerial photographs taken between December 1998 and December 2000. Some photographs were part of a cooperative program between the Japanese International Cooperative Agency (JICA) and the Government of El Salvador and are available the the Salvadoran National Geographic Institute (IGN). Other photographs were acquired by the USGS under contract and are archive at the USGS's Eros Data Center, Sioux Falls, South Dakota. Digital Raster Graphics (DRG) scanned images of 1:50,000-scale quadrangles projected to Transverse Mercator were used as base maps for the mapping. We mapped the cloud cover by first locating it on the aerial photographs using a mirror stereoscope and then manually plotting by inspection a polygon that best represented the shape and size of the landslides onto the base maps. Many of base maps were at a scale of 1:25,000-scale; for some areas, only 1:50,000-scale base maps were available. The mapped areal extent of the landslides were digitized, and then digitally registered to the DRG base maps. Final maps are presented at 1:50,000 scale. Process_Date: 10/2001 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Complete chain Point_and_Vector_Object_Count: 15 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Label point Point_and_Vector_Object_Count: 12 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 12 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Point Point_and_Vector_Object_Count: 176 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000000 Longitude_Resolution: 0.000000 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1927 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: 6378206.400000 Denominator_of_Flattening_Ratio: 294.978698 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: elspremitch.pat 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: AREA Attribute_Definition: Area of feature in internal units squared. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Positive real numbers that are automatically generated. Attribute: Attribute_Label: PERIMETER Attribute_Definition: Perimeter of feature in internal units. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Positive real numbers that are automatically generated. Attribute: Attribute_Label: ELSPREMITCH# 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: ELSPREMITCH-ID Attribute_Definition: User-defined feature number. Attribute_Definition_Source: ESRI Attribute: Attribute_Label: OL Attribute_Definition: 0 = No landslide; 1 = Pre-Mitch Landslide, 9 = Suspected Pre-Mitch Landslides but not field checked Distribution_Information: Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Transfer_Size: 0.028 Metadata_Reference_Information: Metadata_Date: 20020118 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Anthony J. Crone Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: REQUIRED: The mailing and/or physical address for the organization or individual. City: REQUIRED: The city of the address. State_or_Province: REQUIRED: The state or province of the address. Postal_Code: REQUIRED: The ZIP or other postal code of the address. Contact_Voice_Telephone: 303 273-8591 Contact_Facsimile_Telephone: 303 273-8600 Contact_Electronic_Mail_Address: crone@usgs.gov 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 Metadata_Extensions: Online_Linkage: http://www.esri.com/metadata/esriprof80.html Profile_Name: ESRI Metadata Profile