Since a long time, the mineral resources considered inexhaustible and the humanity did not dare to extract them. Recently, several geoscientific studies have asked the question about the scarcity of mineral resources and they even planned some dates of their exhaustion. The example of Hubbert curve, for the "Peak Oil" (K. Hubbert, 1956), extrapolated by some Geoscientists and Economics studies to refer for predicting the peak of mineral resources.
Although, all geoscientific studies are in agreement on the fact that all surface and sub-surface deposits are in stage of depilation. The main questions that still arise are :
- Are there still other mineral resources in the world ?
- Have we good findings and conclusions from the deposits we know ?
- The current metallogenic models are useful for the discovery of unknown deposits ?
Our global stock of mineral substances is still full !
As we know, the internal and external geodynamic cycles is driving the development of mineralization. This is the same cycle that have given rise to existing deposits and by the logic of things, they are able to give birth to the other deposits.
An understanding of the genesis of the deposit involves good field observation
The mining operation is an opportunity to confirm the geological interpretations and refine the ore genesis model. The geological database can be collected to predict the behavior of deposit in the local scale and in some cases, extrapolate the geometric model vertically and horizontally.
A lacks of the prediction parameter in the metallogenic model !
The metallogeny is define as: "a science that studies the mechanisms of deposits geneses and proposes to define methodological tools and guidelines used by geologists". The current context of the evolution of operations and mineral exploration requires the updating of this definition, taking into account the scarcity of the mineral substances.
All geological researches and studies tend to build the geological model of the deposits based on the results of the analyses (geochemistry, geophysics, sedimentology ....) made in the deposits.
The methods and conventional tools are they efficient for the discovery of deposits?
Certainly not, all the conventional methods have shown their limits, hence the work of the R&D that attempt to develop the mining exploration technologies.
The evolution of exploration technology should be more developed, it is not the only one but also the concept of metallogenic model to predict potential areas of deposition of mineralization with a rough estimate of their quality and quantity beyond the conventional methods.
The future challenges of geologists is to find hidden deposits with lower cost with imagine of the shape, quantity and quality of the mineralization. This can be done through the built of a predictive metallogenic model.
This new concept of genesis model of deposits must be built not only by geologist "metallogenist" but also with support of multidisciplinary team composed mainly by geologists, statisticians (specialist in stochastistic for predictive part), mathematicians, chemists etc...
The industrial mining operation does not expects only that the geologist expect the delineation of the deposit, the estimation of reserves and resources and resolution of geological problems encountered during the mining operation. In addition, He expects that the geologist inform him about the extension of potential mineralization and exploration even with a lesser degree of reliability by giving a comprehensive idea about the quantity and quality of mineralization. All of this with a small budget.
Uncertainty is one of the parameters how affecting the metallogenic models!
The metallogenic model is built by observation and analysis linked to the global geological phenomena in order to understand the genesis of deposits. The observations are unperfected and therefore they are subject to uncertainty, more the scale of study is big more the confidence interval of the model reduced.
If the metallogenic model is uncertain how to predict the shape of the mineralization?
A good prediction involves a good understanding of the behavior of mineralization we observe. This understanding can be only done with a solid mathematical and geological modeling.
After the French geologist Louis de Launay (1860-1938), for whom "The metallogenic studies the mineral deposits of the chemical elements, their organizations and especially abnormal concentrations that they present them in industrially form above theaverage .... ". This definition brings out a problem involving non-linear transfer functions wehre the analytical equations are inextricable; this is one of the major applications of nonlinear simulation in geostatistics.
To understand the behavior of physical, chemical and morphological parameters of a deposit, it is not enough to know the concentration levels in a limited area to predict its behavior in the whole area, the spatial distribution of values in the study area is as important as the average value.
However, the simulation at this stage is an approach applied to the observed data (results of conventional exploration tools) to understand the behavior of deposits recognized in a limited area!
Globally, for different type of deposits found in many places, the question arises is: can we developing conditional and / or non-conditional simulation by using of local metallogenic models (made in known deposits) and internal and external geodynamic process to build a predictive model?
The predictive metallogenic model is possible to build if the geoscience community ask the question: how this predictive model looks like?
“All models are wrong, but some are useful” George Edward Pelham Box
Source: https://www.linkedin.com/pulse/new-thinking-concept-metallogenic-model-youssef-daafi?trk=pulse_spock-articles
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