The term gamma-exploration is the use of gamma radiation to make a survey beneath the earth’s surface. By identifying the natural terrestrial gamma radiations, and the amount of attenuation that occurs, we can identify areas of minerals and precious metals lying beneath the earth’s surface, with minimum effort. The radiation is analysed using sensitive scintillation counters with specially dotted crystal sensors in glide mode. In accordance with the search order, gamma spectrum or individual frequencies (isotopes) are analysed. The unit of measurement are ips. (Impulses per second).
We are able to visualize the GPS-based measurement results in Google Earth.
The naturally occurring background radiation which is always present on earth, identifies underground variations by the level and type of radiation being emitted. This so-called background radiation underlies local variations and is influenced by many factors. In particular , the radioactive content of different kinds of rocks varies, e.g.
- granite, which contains quartz, shows a little more radioactivity than basalt
- sulphites and oxides on the other hand reduce the average radiation.
Other changes occur when the background radiation is viewed through kimberlite pipes, the bluish source rock of diamonds. In addition the background radiation shows other changes when it passes through water and oil.
Many ores have by-products, uranium or thorium as well as impurities, which create unstable isotopes, E.g.
- titanium is often found together with thorium
- unstable gold isotope stimulated by impurities and cosmic radiation.
All of the differences can be registered by our scintillation counters (isotope sensors).
Scintillation counters are used for measuring radioactivity, in a variety of disciplines, from medicine to nuclear physics, depending on the sensitivity of the counter. Our scintillation counters are very sensitive and consist mainly of special crystal sensors, of photo multiplier linked to computers all calibrated for geological analysis.
Through these crystal sensors, which consist, depending on the application, of different cultivated crystal combinations, gamma rays are received, converted into light flashes, and strengthened as electric impulses by a photo multiplier. The data is recorded in impulses per second (ips). The strength of the light impulses is proportional to the energy of the minerals being searched for. Therefore, characteristic gamma energy levels are retrievable. The retrieved data recorded by graphical software.
The sensitivity of our scintillation counters allows quick recognition, and processing of the search area.
Depending on the size of the area to be examined, the examination takes can be by foot, 4-wheel-drive vehicle, or by helicopter.
We use the important core and background radiation facts in connection with this method of analysis of the substrate and the exploration of unstable isotopes of elements and take into account in the evaluation. A comprehensive understanding of these facts is the foundation for reading and translating the profile of the "natural" radioactive background radiation.
For more than 25 years we have been working with modified scintillation counters as geo physical measuring devices. As such we are capable of examining areas of any size, not destructively, accurately and in a short period of time. Typically with the aid of a helicopter previously inaccessible areas, can be surveyed quickly and the geological findings presented accurately.