In order to understand natural massives, information is required by means of drilling (samplings and assays) that enable identifying different soil/rock types and mineralogical, structural, mechanical strength and permeability characteristics.
The sampling performed shall represent the natural massive surveyed, enabling essential geological and geotechnical information achievement to develop a project.
If you are interested at this topic, keep on reading this material, let´s approach the following topics:
- What is Drilling in Mining
- Drilling Types
- How to choose drilling type for your project
Shall we go?
What is Drilling in mining
Drilling is executing bores in soil or rock, and sample/core, product generated in drilling, provides information to the region surveyed. It is a very significant stage, for several projects, in civil construction, hydrology, mining or geotechnics, for instance.
Drilling is required to:
- Water catchment projects by means of artesian wells;
- Constructions that need better region soil knowledge;
- Studies related to oil and natural gas;
- Ore deposit survey (greenfield or brownfield);
- Among others.
Drilling Types
There are several drilling types and each one has a specific function.
Main drilling types include :
- Auger drilling;
- SPT percussion drilling;
- Rotary drilling;
- Mixed drilling;
- Geophysical drilling;
Auger drilling
It is a survey method that uses auger as drilling tool. Auger is a soil sampler type comprised by sharp blades, that can be comprised by two pieces, in convex (shell auger) or single shape, in helical shape.
This drilling type is widely used in sanitation and road works.
SPT percussion drilling
Also known as SPT (Standard Penetration Test) drilling, it is a soil survey method which drilling progress is performed through auger or washing, and a sampler driving is used to measure penetration strength indexes, achieve samples, assess water level and execute several assays in situ.
Strike number required to drill the rock enables soil strength assessment. This drilling type is widely used in engineering works.
Rotary drilling
It is a motomechanized set designed to drill rocky massives and achieve rocky material samples with cylindrical shape, core calls. Soils and other materials can also be sampled.
Through rotary drilling, it is possible to achieve great subsoil depths.
It is one of the most widely used methods to rate rocky massives.
Mixed drilling
Mixed drilling, as per its name, is a joint rotary drilling and SPT drilling usage; It is a method that uses percussion drilling to soil section and rotary drilling to rocky section.
Geophysical drilling
Unlike options above mentioned, geophysical drilling does not take soil or rock samples of survey area. The measurements are indirect through seismic, electrical, electromagnetic, potential (magnetic and gravimetric), radiometric, geothermal surveys and methods, etc.
This method can be used to mining, geotechnics and artesian well projects, for instance.
How to choose the best drilling method
The drilling type to be applied in your project can be set forth according to several factors, including:
- Region soil/rock type;
- Place infrastructure, access roads and accessibility;
- Ore type to be surveyed;
- Companies operating in region of interest;
- Bibliography available of the area where the project is to be developed;
It is worth noting that soil drilling/samples must be stored in safe and contamination-free places. In case this action is executed correctly, all work performed previously can be impacted.
The drilling provides basic data that will supply work conceptions foundation and underground and outdoor excavations, slope cut angle, work costs in different project stages, stability calculation, recovery and remedy sizing of contaminated lands, etc. Thus, they are essential for a reliable project and that is concerned with generated data quality.
Rely with Core Case, we have the optimal solution to assist in soil drilling and sample storage for your project.
REFERENCES
Drilling Manual – ABGE 2013
Soil drilling types: what is your work best methodology? Access at: https://blog.apl.eng.br/tipos-de-sondagem-de-solo-qual-a-melhor-metodologia-para-sua-obra/ Mining Drilling. Access at: https://www.geoscan.com.br/blog/sondagem-na-mineracao/
Mining drilling: Methods and Equipment. Access at: https://sagaconsultoria.com/sondagem-na-mineracao-metodos-e-equipamentos/