Changes

The maps in [[:file:using-magnetics-in-petroleum-exploration_fig14-3.png|Figure 2]] are examples of a residual map (A) that was calculated from the total intensity magnetic map (B). The grid and small circles on the total intensity map are the flight path lines [approximately [[length::2 km]] (1.2 mi) apart] and location points for the flight lines. The total intensity map strikingly does not resemble the residual map and would be of limited value for delineating basement fault blocks.

The maps in [[:file:using-magnetics-in-petroleum-exploration_fig14-3.png|Figure 2]] are examples of a residual map (A) that was calculated from the total intensity magnetic map (B). The grid and small circles on the total intensity map are the flight path lines [approximately [[length::2 km]] (1.2 mi) apart] and location points for the flight lines. The total intensity map strikingly does not resemble the residual map and would be of limited value for delineating basement fault blocks.

Total intensity [[magnetics]] responds to rock types over broad areas as well as those deep within the crust. We can see by a careful examination of map B, however, that many of the features shown by the residual map are vaguely apparent in the total intensity data. Fortunately, we no longer have to interpret such total intensity maps in petroleum basins because many enhancement techniques employing residuals, derivatives, polynomials, or [http://wiki.seg.org/wiki/Dictionary:Downward_continuation downward continuation] exist to reveal the subtle magnetic anomalies that result from the changes in rock type across basement block boundaries.

Total intensity [[magnetics]] responds to rock types over broad areas as well as those deep within the [[crust]]. We can see by a careful examination of map B, however, that many of the features shown by the residual map are vaguely apparent in the total intensity data. Fortunately, we no longer have to interpret such total intensity maps in petroleum basins because many enhancement techniques employing residuals, derivatives, polynomials, or [http://wiki.seg.org/wiki/Dictionary:Downward_continuation downward continuation] exist to reveal the subtle magnetic anomalies that result from the changes in rock type across basement block boundaries.

==See also==

==See also==

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Using magnetics in petroleum exploration]]

[[Category:Using magnetics in petroleum exploration]]