Feasibility studies for mineral exploration are aimed at evaluating economic mineral deposits to see if profitable exploitation is possible. The focus of the feasibility study must have an economic bias. As far as mining exploration is concerned, there are three stages such as feasibility, detailed project planning and quality control. The estimation of mineral reserves is the first consideration of the feasibility studies. Only regions containing mineral resources should be the subject of feasibility studies.
The amount and nature of the tasks are variable depending on the scope, the nature of the deposits, the nature of the assignment, etc. Ultimately, the feasibility report should provide an analysis of the investment. The preparation of the feasibility report involves the work of interdisciplinary interests.
Mineral deposits should be evaluated only when preliminary prospecting has shown the possible existence of economic deposits. Generally, preliminary prospecting includes geological reconnaissance, mapping at scales of 1:100,000 or 1:50,000, geochemical and geophysical surveys, some test drilling of geophysical and geochemical anomalies, and finally laboratory tests such as chemical and petrological tests. .
For most deposits, feasibility studies can be done in two phases, but for non-ferrous and precious metals, they involve three phases, as mentioned below.
The first phase could indicate the convenience of moving forward with the remaining phases.
The following tasks are involved in the first phase:
1. Development of infrastructure such as access roads, camping facilities, construction of slopes, magazines for explosives, power lines, generator installation, etc.
2. Depending on the extent of the area under investigation, geological maps should be prepared at scales of 1:1000 or 1:500. Contour intervals can be 3 meters or 5 meters. Topographic maps are also useful.
3. Detailed geophysical and geochemical surveys such as radiometric surveys should be carried out on closely spaced grids. Drilling can be done at intervals from 300 meters to 500 meters.
4. Chemical, petrological and spectrographic analysis can be performed to know valuable minerals.
5. Geological cross sections should be prepared based on the data from the boreholes. They show the attitude of mineralization.
The most intensive exploratory work should be carried out in the selected blocks or block during the second phase. The main task involved in this stage is very close drilling at intervals of 50 to 100 meters. Systematic sampling, analysis of split core samples, bulk samples, etc. to prepare metallurgical and beneficiation reports.
The estimation of the profitability profile is one of the most important objectives of the final phase. The main tasks during this stage include, intensive underground exploratory mining to determine the continuity of the mineral deposit, underground drilling to determine the extent of mineralization, estimation of level or bench reserves, preparation of geological plans, preparation of isocore or isopach maps. . , structure outline plan, metallurgical benefit and tests, and completion of the process flow diagram.
According to experts, a minimum of 30% of the reserves must be incorporated into categories A and B before exploitation of any mineral deposit is considered.