There has been a lot of talk with regards to the magnetic survey’s that have been and continue to be done, I just to post some information with regards to magnetic survey’s and how reliable and valuable they are in mining.

The geophysicist measures the strength of the earth’s magnetic field when he is surveying magnetic areas, of course, this will vary locally depending on the quantity of magnetic material which is in the underlying rocks, to find buried metal objects like underground fuel tanks, magnetic surveying has also been used with considerable success.

The local magnetic field will be strong in the areas where the rocks have high magnetic susceptibility; as is natural, the local magnetic field will be weaker where the rocks have low magnetic susceptibility. This has two applications. Firstly, deposits with magnetic minerals – for example, skarns, nickel deposits bearing pyrrhotite and iron deposits – can be directly detected using magnetic surveying. Secondly, magnetic surveying can be used as a help to geological mapping. Units which have higher susceptibility will show up as areas of high strength in the magnetic field.

Magnetic surveys do not necessarily have to be done on the ground. An aerial magnetometer is a highly sensitive instrument which can either be trailed below a helicopter or an airplane, or it can be mounted on an aircraft in a “stringer” as it can be called. If you combine readings from this instrument with repeated aerial video photography, a magnetic map of a large area can be plotted. The geological agencies which are controlled by the government frequently contract for aerial surveys, they publish the results with the intention of encouraging exploration.

I will post more if you fell it’s worth reading.

Long and Strong

LS