SILVA, A. L.; SILVA, Alana Lopes.
Résumé:
Many mineral deposits are abandoned, after the exploration step, due to adverse
geotechnical factors. These unsuccessful entrepreneurships end up representing financial
losses to companies and environmental damages which may be avoided, i f a previous
research is conducted. In the extraction of ornamental rocks, preserving the entireness of
the rock is a fundamental factor to completely exploit a deposit, maximizing the reserves
and increasing quality and commercial value of extracted blocks. For this reason, as it is a
risky activity, it is necessary to be more precise in the prospective phase of the research for
the quarry of those areas, in which low knowledge of geological and geotechnical aspects
of the studied regions may compromise the exploitation The modeling of the geologic and
geotechnical uncertainties started to be one technique of great utility in the sector of
ornamental rocks, since its applicability results in a detailed knowledge of the risks which
affect the deposit. With base in characteristics as faults, joints, fractures and mineralogical
alterations, it was developed a methodology applicable to deposits of ornamental rocks
which is able to represent discontinuities in three-dimensional graphics and calculation of
the probable recovering of the quarry. The application of the methodology in a study of
case real made possible a planning of more versatile plowing, providing the creation of
sceneries with the planning parameters, and allowing of that form larger speed and
precision in the analyses and in the control of quality of the quarry. The application of this
methodology to a real study case allowed the elaboration of more versatile exploitation
plans of deposit, making it possible to create settings with planning parameters, decreasing
the time required to analyse and increasing the certainty of the analysis in the exploitation
quality control of the deposit. The study case was conducted in an area located in the State
of Paraiba, in Picui County. It is an ornamental granite deposit, consisting of large-ovalshaped
rocks, as well as rock mass outcrops. The deposit presented breakings of different
types and height. Therefore, it was an excellent place to conduct a study to contribute to
the development of a methodology able to help entrepreneurs of the sector of ornamental
rocks to decide how much to invest in researches to exploit areas with similar risk profiles,
increasing the quality and profitability of the entrepreneurships. The methodology was
proved efficient, permitting a higher control of economical risks, thus, beyond the isolation
of the areas in which there were breakings, it also permitted the assessment of the
theoretical recovery of the usable areas, being worthwhile to future works in the sector of
ornamental rocks.
