Future ores sought kilometers underground
- What we want to do now is a little more sophisticated methods to understand where they go in depth and build a three dimensional model of it, says Pär Weihed Professor of Ore Geology, Luleå University.
He heads a European research project on 4D modeling as part of a larger European mining venture named Pro Mine. 7 countries participate in the collaboration, which account for about 90% of Europe's production of metals. The national funding for the project comes from the state mining research program totaling 100 million. The project is implemented in cooperation with the mining company Boliden and expected to last at least another 1 ½ years.
It is known today, by mapping the surface, quite well how the rock looks like in for example, Skellefteå field, between Boliden and Kristineberg in the east to the west. But how it looks in a three-dimensional perspective on the depth remains to find out.
By inserting various geological and geophysical data in the model that accounts for the three-dimensional perspective, one can obtain information on how the ore distribution at depth look. (The fourth dimension describes the historical perspective of how the rock influenced over time by eg deformation.) Seismic data belonging to the 3D perspective is an important information that can be taken into the model and beeing delivered by a partner in the project at Uppsala University. It does so by shooting seismic profiles over an area which gives reflectors from different geological units. On the basis of that information, you can predict how different ore areas extending down from the mines.
The reason to the ongoing project is that on the European level today almost all ores are already found in the surface level, and that the European rawmaterial supply conditions in the long term must be secured. Mankinds dependence on metals is, according to Per Weihed, much bigger than we think.
According to an estimate made by (MII) Mineral Information Institute, a human beeing needs 1700 tons of minerals, metals and petroleum products during it's lifetime, and therefore one needs to also look in depth to ensure that demand. On geological grounds, researchers believe that there are just as many tons of ore at depth of 500 meters, as for 1000 meters depth, and perhaps down to 1500 meters.
- It's a great challenge and we know it's there somewhere and this is a help for the exploration industry to determine where to make their efforts, says Pär Weihed.
