Gravity anomaly of a dipping prism

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SUMMARY

This discussion focuses on calculating the gravity anomaly of a dipping prism using MATLAB, specifically employing the equations of Hjelt from the 1974 publication in Geoexploration. The formula Δg=G.Δρ.T0 is central to the calculations, with specific attention to the interpretation of the indices in the equations. The conversation highlights the complexity of the notation used by Hjelt and suggests deriving simpler cases, such as rectangular prisms, to better understand the gravity effects. Additionally, it recommends consulting Telford et al. (1990) for clearer notation and foundational concepts in gravity methods.

PREREQUISITES
  • Understanding of MATLAB programming for scientific calculations
  • Familiarity with gravity anomaly concepts and equations
  • Knowledge of geophysical methods, particularly gravity methods
  • Basic comprehension of mathematical notation used in geophysics
NEXT STEPS
  • Study the equations presented by Hjelt in Geoexploration for gravity anomalies
  • Learn about the gravity effect formula for rectangular prisms and semi-infinite slabs
  • Review Telford et al. (1990) on gravity methods for clearer notation and applications
  • Explore MATLAB scripting techniques for implementing geophysical calculations
USEFUL FOR

Geophysicists, MATLAB programmers, and students studying gravity anomalies and their applications in geophysical exploration will benefit from this discussion.

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I am trying to write a MATLAB script which calculates the gravity anomaly of a dipping prism, using the equations of Hjelt, published in Geoexploration in 1974, issue 1 volume 12.
Δg=G.Δρ.T0
where
http://img580.imageshack.us/img580/6528/41828644.png
and
http://img31.imageshack.us/img31/4226/phiih.png
at the end of the page there are two notes, the second one says:
"Note 2: The sign of each \phi is positive, whenever there is an even number of 2s in the indices
of u, v and w. (u1, - v1 - w1, u1 - v2 - w2, etc.)"

I just can't get my head around what exactly this means and how to apply it.I have expanded the equations for each \phi, using the limits for u, v and w, but they are very long, so will post them only if needed.
 
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I had a quick read of the paper. Granted, the notation that the author uses is not clear and rather cumbersome.

I am not sure whether this helps, but if I were you, I would derive the gravity effect formula for a simple case (i.e. rectangular prism, semi-infinite slab, etc) and see how the results work out.

I do not have it at hand right now, but Telford et al., 1990 (Applied Geophysics) has a decent section on gravity methods. I would also take a look at Telford as I recall the notation is clearer.

cheers.
 
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I think Telford gives the equations only for 2D anomalies
 

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