Mineral Exploration Excellence by Capstone Geo Consultants

This has been one of the pioneering projects in the chapters of Capstone’s history. The objective was to delineate zones of potential manganese mineralization in a British era abandoned mine in 02 blocks with a cumulative area of about 3.6 sq. km. Scope of work catering to the objective included,

Establishing benchmark referenced stations for observations in a regular grid.
Undertake microgravity survey occupying the observation stations.
Generate Bouguer gravity anomaly to identify mineralization zones.
Undertake 2D Electrical Imaging (Resistivity & IP) on selective zones of bouguer anomaly.
Delineate prospective mineralization zones on 2D section.
Comprehensive analysis in identifying mineralized bodies (depth/volume).
Recommend verification drilling to cross-examine results.

Challenges in the project included, thick vegetation, precarious slopes, old pits & shafts and abandoned underground mines.

Bouguer gravity anomaly data assisted in identifying areas with dense mass (high gravity anomaly) owing to higher density of manganese material. 2D Electrical Resistivity Imaging helped in evaluating the presence, depth & configuration within a complex folded regime. The investigation led to new discoveries of mineralization pockets that remain unexploited in the deposit, paving way to enhanced resource potential in the deposit.

This is one among the most comprehensive assignments and longest running projects in the early history of Capstone. The prospect spanned across 980 sq. km. in the sub-central region of Mauritania in the fringes of Sahara Desert, primarily containing magnetite ore. Several milestones have been achieved in the program starting with regional investigation and culminating with feasibility studies. The program included,

Regional studies & literature review.
Airborne geophysical studies identifying major anomaly areas.
Remote Sensing studies identifying potential signature of iron mineralization.
Ground Reconnaissance survey.
Comprehensive studies to identify potential blocks for ground survey.
Geochemical mapping, sampling, and laboratory analysis.
High Resolution Ground Magnetic & Geological mapping.
Preliminary Beneficiation studies.
Hydrogeological studies.
Drilling Exploration.
Resource Modelling and Feasibility Studies.

Being a large area, interpretation of Airborne data helped in narrowing zones of potential mineralization. Analysis of Remote Sensing dataset in genres of LANDSAT & ASTER were analysed for lithology & iron ore signature; Geological & Geochemical Mapping in the identified potential zones (regional scale) assisted in target definition for ground magnetic survey. One of the potential areas was targeted, covering 185 sq km in 3500 LKM of magnetic survey and more than 18500 m of drilling exploration. Resource modelling of the sampled data from the drill holes indicated a 5.4 million Tons (Mt) of Measured, 7.8 Mt of Indicated and 32 Mt of Inferred Resources of Magnetite with an average grade of 25% Fe.

This project was yet another milestone in identifying iron ore resources in a complex geological environment in Western Ghat regions in Goa. 02 blocks with approximate coverage of about 02 sq. km. in a highly rugged & thickly vegetated conditions were evaluated using geophysical technique.

The scope of work included,

Coverage of area with grid-based ground magnetic survey.
Identify anomaly related to mineralization from Ground Magnetic data.
Undertake 2D Electrical Resistivity Imaging over anomaly zones.
Comprehensive analysis to suggest nature of mineralization & volume of ore.
Recommendation for drilling based verification of geophysical results.

A total of about 2200 magnetic stations were observed & data acquired in the coverage area. Several 2D Electrical Imaging (Resistivity) with a total of 3.2 LKM lead to identification of tentative mineralization pockets. Based on the composite results about 20 verification drill holes were proposed. With this exercise client could identify additional resources in their existing mines.

This project added another feather to team Capstone’s capabilities & endurance under challenging conditions. Objective of the project was to delineate zones of potential iron ore (hematite) occurrence in 05 blocks covering a total of about 09 sq. km.

The task included,

1. Ground magnetic survey at 100 m line interval and 20 m station spacing for data acquisition.
2. Identify inferred potential mineralization zones based on magnetic anomaly.
3. Undertake 2D Electrical Resistivity Imaging over identified magnetic anomaly zones targeting a depth of about 90 m below ground level.
4. Interpret results & comprehend on tentative resources available in the area.
5. 3-Dimensional model for assessment of the potential resources.
6. Recommend drilling based verification locations based on above.

The investigation covered more than 4500 Magnetic stations in about 230 LKM of survey. Potential zones were identified in the magnetic anomaly map followed with 2D Electrical Imaging for a total of 72 LKM. The challenges included terrain, vegetation, accessibility, & social conditions. The team overcame all these challenges to complete the project in time. Capstone’s intervention helped client in identifying tentative resource areas, adding to about 50 million tons.

Capstone has undertaken similar jobs for the same client in Barsua Iron Ore Mines in Sundergarh, Odisha.

This project entailed review of mining plan under MCDR/2017 for 03 Mining Lease areas covering an extent of 6.293 Ha, 6.2 Ha & 8.288 Hectare.

The scope of work included,

Verification of boundary pillar coordinates using DGPS survey & authentication by ADMG, Kurnool.
Review of the approved Mining Plan & scheme of mining of the previous years.
Review of the previous approved proposals in respect of exploration, excavation & reclamation, Mine Production & Development, Waste Management, Afforestation & Compliance.
Phase wise Exploration including Diamond Core Drilling, Sample Analysis, Preparation of Plans & Cross-sections, Future Exploration Program etc.
Calculation of Reserves & Resources (as per UNFC), Feasibility Studies, Petrographic & Mineralogical Studies, Geo-statistical Analysis.
Review of Mining Method, Waste Disposal, Conceptual Mining Plan, Mining & Processing Mine Drainage, Mineral Stacking, Processing of RoM & Progressive Mine Closure Plan (PMCP), Review of EIA parameters & Progressive Reclamation Plan, Financial Assurances etc.

The reports duly completed according to Indian Bureau of Mines (IBM) guidelines were submitted & approvals were received with necessary permission to continue with the mining operations.