Magnetic Anomalies of New Jersey contains a GIS shapefile of magnetic contours as polygons, at 100 gamma intervals. The contours are based on magnetic data in New Jersey and vicinity. The New Jersey contours were clipped at the state outline.The magnetic anomalies at 100-gamma intervals have lows ranging from -200 to -300 gammas and highs ranging from +1200 to +1300 gammas. A regional gradient was removed by using a corrected geomagnetic reference field. For New Jersey the field is 55,000 - 56000 gammas.
I. Description of Data to be Provided. The Data provided herein are distributed subject to the following conditions and restrictions. SUBJECT DATA LAYERS For all data contained herein, NJDEP makes no representations of any kind, including, but not limited to, the warranties of merchantability or fitness for a particular use, nor are any such warranties to be implied with respect to the digital data layers furnished hereunder. NJDEP assumes no responsibility to maintain them in any manner or form.
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Bond, K.R., and Zietz, Isidore, 1987, Composite magnetic anomaly map of the conterminous United States west of 96 degrees longitude: U.S. Geological Survey Geophysical Investigations Map GP-977, 2 sheets, scale 1:2,500,000, 13-p. text.
Geological Society of America, Committee for the Magnetic Anomaly Map of North America, 1987, Magnetic anomaly map of North America: Geological Society of America, scale 5,000,000.
Godson, R.H., 1986, Description of magnetic tape containing conterminous United States magnetic data in a gridded format: National Technical Information Service Report PB86-197423, 5 p., magnetic tape.
Hinze, W.J., and Zietz, Isidore, 1985, The composite magnetic-anomaly map of the conterminous United States, in Hinze, W.J., ed., The utility of regional gravity and magnetic anomaly maps: Tulsa, Okla., Society of Exploration Geophysicists, p. 1-24.
U.S. Geological Survey, 1982, Composite magnetic anomaly map of the United States; Part A--Conterminous United States: U.S. Geological Survey Geophysical Investigations Map GP-954-A, 2 sheets, scale 1:2,500,000, 59-p. text.
Webring, M. W., 1981, MINC-- A gridding program based on minimum curvature: U. S. Geological Survey Open-File Report 81-1224, 41 p.
The data, originally gridded on a 2-km interval using the spherical Transverse Mercator projection of the Magnetic Anomaly Map of North America, were reprojected to the Albers projection used on this CD-ROM and regridded on a 2-km interval using a minimum curvature gridding program (Webring, 1981). An interpretation of the 1982 anomaly map was presented by Hinze and Zietz (1985).
The grid was converted to New Jersey State Plane feet.The magnetic values were gridded (kriging) and contoured. The contoured data were converted to DXF file format and exported to ESRI's ARCINFO polygon coverage. The polygon coverage was then converted to shape file using ESRI's ArcView 3.2. Each polygon was assigned a range of contour values in gammas or NanoTeslas. Then using the New Jersey state outline New Jersey contours were clipped from data from the surrounding states for this shape file.