Citation:
Citation_Information:
Originator: U.S. Geological Survey and the Department of Interior
Publication_Date: 2012
Title: Airborne geophysical survey: Northwest Montana '65
Geospatial_Data_Presentation_Form: analog contour map
Online_Linkage:
Description:
Abstract:
Aeromagnetic data were collected along flight lines by instruments in an
aircraft that recorded magnetic-field values and locations. In the earlier
days of surveying, the only way to represent this data was to generate an
analog map with contour lines. This dataset is a representation of the
digitized contour lines either by following the lines or by choosing the
intersection of the contour and flight-line to create a value of the magnetic
field. The values presented are latitude, longitude, and map magnetic-field
values.
Purpose:
Aeromagnetic surveys are used for geophysical prospecting. Some variations in
magnetic measurements are caused by rocks that contain significant amounts of
magnetic minerals (magnetite being the most common). These anomalies reflect
variations in the amount and type of magnetic material and the shape and depth
of the body of rock. The features and patterns of aeromagnetic anomalies can
also be used to delineate details of subsurface geology including the locations
of buried faults and the thickness of surficial sedimentary rocks.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19651009
Ending_Date: 19651031
Currentness_Reference: ground condition
Status:
Progress: complete
Maintenance_and_Update_Frequency: none planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -113.48
East_Bounding_Coordinate: -111.00
North_Bounding_Coordinate: 48.22
South_Bounding_Coordinate: 46.53
Data_Set_G-Polygon:
Data_Set_G-Polygon_Outer_G-Ring:
G-Ring:
-111.70 48.22, -111.00 47.14, -112.78 46.53,
-113.48 47.63, -111.70 48.22
Keywords:
Theme:
Theme_Keyword_Thesaurus: USGS Metadata Identifier
Theme_Keyword: USGS:c7131162-7a13-4278-9bf6-a835a542d7f7
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: geophysical surveys
Theme_Keyword: aeromagnetic data
Theme_Keyword: airborne surveys
Theme_Keyword: magnetic surveys
Theme_Keyword: residual magnetic field
Theme_Keyword: total field
Theme_Keyword: magnetic
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: geophysics
Theme_Keyword: geospatial datasets
Theme_Keyword: magnetic field (earth)
Theme_Keyword: aeromagnetic surveying
Theme_Keyword: field monitoring stations
Place:
Place_Keyword_Thesaurus: none
Place_Keyword: United States
Place_Keyword: Montana
Place_Keyword: MT
Place_Keyword: Great Falls
Place_Keyword: Mission Range
Place:
Place_Keyword_Thesaurus: Common Geographic Areas
Place_Keyword: f30013 = Cascade
Place_Keyword: f30015 = Chouteau
Place_Keyword: f30029 = Flathead
Place_Keyword: f30049 = Lewis and Clark
Place_Keyword: f30059 = Meagher
Place_Keyword: f30063 = Missoula
Place_Keyword: f30073 = Pondera
Place_Keyword: f30077 = Powell
Place_Keyword: f30099 = Teton
Access_Constraints: none
Use_Constraints:
none. Acknowledgement of the U.S. Geological Survey would be appreciated
in products derived from these data.
Browse_Graphic:
Browse_Graphic_File_Name:
Browse_Graphic_File_Description:
Reduced-size image depicting the data, 1118 x 996 pixels, 245,481 bytes
Browse_Graphic_File_Type: JPEG
Data_Set_Credit:
These USGS employees contributed to reformatting and archiving these data:
Viki Bankey, Pat Hill, Holly Hindle,
Bob Kucks, Sarah Shearer, Esther Castellanous
Cross_Reference:
Citation_Information:
Originator: U.S. Geological Survey
Publication_Date: 1965
Title:
Aeromagnetic, Bouguer gravity, and generalized geologic studies of the
Great Falls-Mission Range area, northwestern Montana
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: U.S. Geological Survey Professional Paper
Issue_Identification: PP-726A
Publication_Information:
Publication_Place: Denver, CO
Publisher: U.S. Geological Survey
Other_Citation_Details:
by M.D.Kleinkopf and M.R. Mudge
19 pages
map scale 1:250,000