1.3 A cross section through the gravity and magnetic fields

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1.3 A cross section through the gravity and magnetic fields
These models show a vertical section through the gravity and magnetic fields, and their respective derivatives. The section is an East-West section drawn through the middle of the models used in sections 1.1 and 1.2. Each section (at equal horizontal and vertical scale) shows how the intensity of the field decays with height above the body, and at what height the distinct anomalies associated with each body merge with each other. Notice the correlation between the first vertical derivative of the gravity field and the total field magnetics.

Click on the images to launch Noddy. A legend is provided at the end of this page.

East-West sections with altitude variations from 0 m to 2000 m

Gravity

0 m	200 m	400 m	600 m
800 m	1000 m	1200 m	1400 m
1600 m	1800 m	2000 m

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Gravity First Vertical Derivative

0 m	200 m	400 m	600 m
800 m	1000 m	1200 m	1400 m
1600 m	1800 m	2000 m

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Magnetics

0 m	200 m	400 m	600 m
800 m	1000 m	1200 m	1400 m
1600 m	1800 m	2000 m

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Magnetics First Vertical Dertivative

0 m	200 m	400 m	600 m
800 m	1000 m	1200 m	1400 m
1600 m	1800 m	2000 m

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Geology

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Key Survey Parameters Scale

plugs & dykes

r = 1 k = 10^-2

background

r = 0 k = 0

image width

10,000 m

image height

2,000 m

inclination

-90°

intensity

70,000 gamma

flying height

0 m to 2000 m

max

min

WWW conversion by Ian Brayshaw