nrm_maxspot.shp - Digital dataset of horizontal gradients of the long wavelength anomalies and their maxima for the Northern Rocky Mountains and adjacent areas, Idaho, Montana, Washington, Oregon, and Wyoming.

Metadata also available as

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Mankinen, Edward A.
Originator: Hildenbrand, T.G.
Originator: Zientek, M.L.
Originator: Box, S.E.
Originator: Bookstrom, A.A.
Originator: Carlson, M.H.
Originator: Larsen, J.C.
Publication_Date: 2004
Title:
nrm_maxspot.shp - Digital dataset of horizontal gradients of the long wavelength anomalies and their maxima for the Northern Rocky Mountains and adjacent areas, Idaho, Montana, Washington, Oregon, and Wyoming.
Edition: version 1.0
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2004-1413
Publication_Information:
Publication_Place: Menlo Park, California
Publisher: U.S. Geological Survey
Online_Linkage: <http:/pubs.usgs.gov/of/2004/1413/>
Description:
Abstract:
Regional aeromagnetic surveys reflect measurements of the intensity of the Earth’s magnetic field relative to the International Geomagnetic Reference Field. Although the geomagnetic field is complex and affected by both internal and external sources, their effects are generally well characterized allowing the isolation of magnetic fields due to crustal sources. Data for a specific area, however, usually derive from numerous individual surveys with widely varying flight specifications. By merging such disparate data sets to a common datum, aeromagnetic maps and their derivatives can be used to characterize local magnetic variations in the middle and upper crust. The dataset, nrm_maxspot.shp, contains point data in ESRI shapefile format showing maxima in the horizontal gradient of long-wavelength magnetic potential (nrm_mpot_lw).
Purpose:
This dataset was created to assist in developing regional digital earth science data and interpretations that can be used by Federal land managers in regional planning and special assessments such as road-less area withdrawals.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2004
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -118.381970
East_Bounding_Coordinate: -107.338330
North_Bounding_Coordinate: 49.114310
South_Bounding_Coordinate: 41.921730
Keywords:
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: geophysics
Theme_Keyword: geophysical map
Theme_Keyword: maxima
Theme_Keyword: magnetic anomaly
Place:
Place_Keyword: Idaho
Place_Keyword: Montana
Place_Keyword: Washington
Place_Keyword: Oregon
Place_Keyword: Wyoming
Place_Keyword: Northern Rocky Mountains
Place_Keyword: USA
Access_Constraints: none
Use_Constraints: none
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Edward A. Mankinen
Contact_Organization: U.S. Geological Survey
Contact_Position: geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 345 Middlefield Rd.
City: Menlo Park
State_or_Province: CA
Postal_Code: 94025
Country: USA
Contact_Voice_Telephone: 1-650-329-4669
Contact_Facsimile_Telephone: 1-650-329-4664
Contact_Electronic_Mail_Address: emank@usgs.gov
Native_Data_Set_Environment:
Microsoft Windows 2000 Version 5.1 (Build 2600) Service Pack 1; ESRI ArcGIS 8.3; ESRI ArcView 3.2; Adobe Illustrator 10
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The original NAMAG (2002) data was collected from multiple contractors or groups using different instruments. The accuracies of these measurements typically range from 1 to 10 nanotesla (nT). Max spots are based on gradients at given locations, which could shift slightly depending upon the gridding algorithm. Also, the product is interpretive and the placement and arrangement of the points could be modified.
Logical_Consistency_Report: No duplicate features exist.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Horizontal position of the survey aircraft used to collect data were determined by one of three ways: reconciling down-looking photographs with topographic maps and orthophotoquadrangle maps, aircraft navigational systems, or GPS (NAMAG, 2002)
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
The effect of the combination of band-pass filtering and pseudo-gravity transformation has not been determined.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: North American Magnetic Anomaly Group
Publication_Date: 2002
Title:
Digital data grids for the magnetic anomaly map of North America
Geospatial_Data_Presentation_Form: raster digital data
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 02-414
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Online_Linkage: <http://pubs.usgs.gov/of/2002/ofr-02-414>
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2002
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: NAMAG (2002)
Source_Contribution: This is the source of the magnetic anomaly data
Source_Information:
Source_Citation:
Citation_Information:
Originator: Hildenbrand, T.G.
Publication_Date: 1983
Title:
FFTFIL: A filtering program based on two-dimensional Fourier analysis
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 83-237
Publication_Information:
Publisher: U.S. Geological Survey
Type_of_Source_Media: paper
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1983
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Hildenbrand (1983)
Source_Contribution:
Provided the program used to calculate the upward continuations and the pseudogravity transform.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Phillips, J.D.
Publication_Date: 1997
Title: Potential-field geophysical software for the PC, version 2.2
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 97-725
Publication_Information:
Publisher: U.S. Geological Survey
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1997
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Phillips (1997)
Source_Contribution: Provided the program used to filter the wavelength data.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Blakely R.J.
Originator: Simpson, R.W.
Publication_Date: 1986
Title:
Approximating edges of source bodies from magnetic or gravity anomalies
Series_Information:
Series_Name: Geophysics
Issue_Identification: v. 51
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1986
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Blakely and Simpson (1986)
Source_Contribution:
Outlined the procedure used to calculate the horizontal gradients and maximum values of the long-wavelength magnetic potential
Process_Step:
Process_Description:
These data were extracted from the published magnetic anomaly grid for North America (NAMAG, 2002) and re-projected to the specifications of the study area using USGS in-house developed software. In-house software was used to convert from USGS grid format to ARC/INFO grid format. The grid was saved as, nrm_aeromag.
Source_Used_Citation_Abbreviation: NAMAG (2002)
Process_Date: 2002
Process_Step:
Process_Description:
The gridded aeromagnetic data (nrm_aeromag) were converted to their magnetic potential ("pseudogravity") using USGS in-house developed software. In-house software was used to convert from USGS grid format to ARC/INFO grid format. The grid was saved as, nrm_mpot. Pseudogravity transform performed using the algorithms of Hildenbrand (1983).
Source_Used_Citation_Abbreviation: Hildenbrand (1983)
Process_Date: 2003
Process_Step:
Process_Description:
The gridded magnetic potential dataset (nrm_mpot) was filtered to isolate prominent wavelengths in the dataset using USGS in-house developed software. This grid contains the long-wavelength data. In-house software was used to convert from USGS grid format to ARC/INFO grid format. The grid was saved as, nrm_mpot_lw. Filtering was performed using the matched bandpass filtering algorithms of Phillips (1997). Upward continuation performed using the algorithms of Hildenbrand (1983).
Source_Used_Citation_Abbreviation: Phillips (1997)
Source_Used_Citation_Abbreviation: Hildenbrand (1983)
Process_Date: 2003
Process_Step:
Process_Description:
Lineaments were determined by visual inspection of the horizontal gradient field along with the maximum values and the gradient "ridges" containing them. These maximum value point data were imported into Arc View 3.2 and converted to ESRI shapefile. The method of Blakely and Simpson (1986) was used to calculate the horizontal gradients and their maximum values.
Source_Used_Citation_Abbreviation: Blakely and Simpson (1986)
Process_Date: 2003
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Entity point
Point_and_Vector_Object_Count: 15974
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 795
Column_Count: 827
Vertical_Count: 1
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: nrm_maxspot
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: LONGITUDE
Attribute_Definition:
Longitudinal coordinate of the feature location, expressed in decimal degrees.
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: LATITUDE
Attribute_Definition:
Latitudinal coordinate of the feature location, expressed in decimal degrees.
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: MAGNITUDE
Attribute_Definition: Feature value
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey Information Services
Contact_Address:
Address_Type: mailing address
Address: P.O. Box 25286
City: Denver
State_or_Province: CO
Postal_Code: 80225
Country: USA
Contact_Voice_Telephone: (888) ASK-USGS
Contact_Voice_Telephone: (888) 275-8747
Contact_Electronic_Mail_Address: infoservices@usgs.gov
Resource_Description: Downloadable data for USGS Open-File Report 2004-1413
Distribution_Liability:
The U.S. Geological Survey (USGS) provides these geographic data "as is." The USGS makes no guarantee or warranty concerning the accuracy of information contained in the geographic data. The USGS further makes no warranties, either expressed or implied as to any other matter whatsoever, including, without limitation, the 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 computers of the USGS, no warranty, expressed or implied, is made by the USGS regarding the uses of these data on any other system, nor does the fact of distribution constitute or imply any such warranty. In no event shall the USGS have 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 or arising out of the delivery, installation, operation, or support by the USGS.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: ZIP
Format_Version_Number: 9.0
Format_Specification: WINZIP® 9.0
Format_Information_Content:
ZIP archive for six ESRI shapefiles: nr_gravlin.shp, nrg_maxspot.shp, nrg_mxspt_iw.shp, nrm_maglin.shp, nrm_maxspot.shp, and nrm_mxspt_iw.shp
File_Decompression_Technique:
To open a ZIP archive, double-click on the archive listed in My Computer or Windows Explorer, drag and drop the archive onto WINZIP®, or use the standard Open dialogue box.
Transfer_Size: 11 (MB)
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <http://pubs.usgs.gov/of/2004/1413>
Fees: No fee for downloadable data and report
Technical_Prerequisites:
User must have geographic information system (GIS) software capable of reading ESRI ArcInfo® file formats.
Metadata_Reference_Information:
Metadata_Date: 20050929
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Jeremy C. Larsen
Contact_Organization:
Information Systems Support (under contract to the U.S. Geological Survey)
Contact_Position: contractor
Contact_Address:
Address_Type: mailing and physical address
Address: 904 W. Riverside Avenue, Rm. 202
City: Spokane
State_or_Province: WA
Postal_Code: 99201
Country: USA
Contact_Voice_Telephone: 1-509-368-3101
Contact_Facsimile_Telephone: 1-509-368-3199
Contact_Electronic_Mail_Address: jlarsen@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
Generated by mp version 2.8.6 on Thu Sep 29 09:28:54 2005