Mineral Exploration

Tel: (07) 3316 2531 Fax: (07)3295 9570www.oresomeresources.com

Demand for minerals (especially from the developing world)

Demand for products made from minerals.

Why explore for minerals?

Predicted demand for copper world wideSource: Courtesy of Queensland Government Dept Mines and Energy

Satellite photographs

(remote sensing)Remote Sensing is the science and art of acquiring information without coming

into physical contact with the objects. In remote sensing, information transfer is accomplished by use of electromagnetic radiation (EMR). EMR is considered to span the spectrum of wavelengths from 10 mm to cosmic rays up to 1010 mm.

Energy Interactions, Spectral Reflectance and Colour Readability in Satellite ImageryAll matter is composed of atoms and molecules with particular compositions. Therefore, matter will emit or absorb electro-magnetic radiation on a particular wavelength with respect to the inner state. All matter reflects, absorbs, penetrates and emits Electro-magnetic radiation in a unique way. Electro-magnetic radiation through the atmosphere to and from matters on the earth’s surface are reflected.

Therefore, each mineral is highlighted on the satellite imagery at a particular wavelength (colour)

Difficult to find

Deeper locations

Grades of ore are lower

The search begins

Satellite Image

Size and quality of the deposit

Geographical location

Depth at which it is found

Environmental impact

Marketability

Is it worth mining?

Satellite Imagery

Magnetometers

Aerial Exploration

Source: Queensland Resources Council

Magnetic Surveys

The orientation and strength of the earth’s magnetic field has been measured and studied in detail at many locations.

A magnetic high is where the measured field strength is higher than the value predicted by the global model, and a magnetic low is where the measured field strength is lower than the value predicted by the global model. 

In most cases these rock masses contain the mineral magnetite.  Rocks which contain lots of magnetite include gabbro, diorite, basalt and other “mafic” igneous rocks.  These rocks will show up as a strong magnetic high on a map of the total field strength. 

Felsic igneous rocks, like granite or rhyolite, and most sedimentary rocks are notably non-magnetic except in rare cases.  These rocks may show up as distinct magnetic lows.

Measure the earth's magnetic and gravitational and electrical properties

Aerial Geophysical Surveys

Image courtesy of Queensland Government Dept Mines and Energy

Measure:• the earth’s magnetic conditions• resistance to the electric current • local gravitational effects

Geophysicists

Image courtesy of Queensland Government Dept Mines and Energy

Indicates a viable spot

Maybe worth mining

Can lead to aerial surveys

Applies computer manipulation to maps to secure more information

An anomaly

Land based exploration

Source: Queensland Resources Council

Analyse the mineral content of soil, water, vegetation

Provide indications on what lies beneath the surface.

Geochemists

Image courtesy of Queensland Government Dept Mines and Energy

Surface Drilling

Source: Queensland Resources Council

Surface and Ground Water

Ground water collected from wells, springs, and drill holes may provide clues to the presence of covered deposits. This water moves very slowly through the overburden until it discharges at the surface as a spring or seeps into a body of water.

Subsurface flow rates vary from almost zero to over 100 feet per year. The slower rates cause water to have a longer contact time with the subsurface gravels, rocks, and, if present, ore deposits, permitting minute amounts of metals to be leached from the rocks.

Detecting gold in a ground-water

dispersion pattern requires an

extremely sensitive analytical

technique which measures gold in

water at the one-part-per-trillion (ppt)

determination level.

• Collate and analyse information from maps, geophysical aerial surveys, satellite images and previous surveys

• Use information from the geological survey sections of state government mines departments, Geoscience Australia

Geologists

Source: Queensland Resources Council

Economic Assessment

Exploratory Shaft

Ore Analysis

Further studies

Image courtesy of CSIRO

Commercial Viability

Environmental Affects

Community support

The final decision!

Distribution of metal deposits in QueenslandImage courtesy of Queensland Government Dept Mines and Energy