by RADU BOTEZATU
Institute for Oil, Gas and Geology, Bucharest, Romania
An analytical expression of a gravity curve can be obtained using the least
squares method, as an n-degree polynomial of the distances x. Such a mathematical
relation can then be treated in many ways, in view of obtaining supplementary
information on the anomalous sources of gravity anomalies. This method is valuable
for determining the regional anomalies, and for the treatment of local ones
as well. Two fundamental types of gravity anomalies are studies in this paper:
the "bell-type" and the "step-type".
The use of the classical form of the least squares method applied to polynomials
up to degree 6 does not give good results to approximate the gravity anomalies
and it is necessary to enlarge by far the number of polynomial terms to obtain
a valuable solution.
Using some special initial conditions, only restricting the generality, the
least squares method can be applied in a simplified form on a polynomial of
degree 5 or 6 with good results. This practical procedure, elaborated by the
author, is presented in this paper and its possibilities and limitations are
discussed.
An example of practical application on a real gravity anomaly mapped in Romania
is given in the last section of the paper, to test the validity of the proposed
procedure.