That is what is available with VK1, an airborne gravity gradiometer.
It works on the principle that orebodies have specific gravity signatures.
Basically an aircraft flies about 80m above the earth and the extremely sensitive sensor in the device reacts to those gravity signatures.
The machine is the brainchild of Dr Frank van Kann – hence the VK nomenclature – who first came up with the idea in 1979.
Of course back then the sort of computing and engineering technology available to put together such a device were in the realms of science fiction.
Indeed, the first flight of the first complete VK1 system took place in August 2010.
To give an idea of the sensitivity of the machine, it can pick up gravity signatures 100 million times less than the oscillation within the plane.
The housing those sensors sit within removes a large amount of the vibration from the aircraft.
To give an idea of how effective that is, Rio showed a video of a glass of wine sitting atop the VK1.
The meniscus of the fluid within the glass moves not a jot. The camera then pans out to show how violently the housing is being shaken.
It was actually linked to a motion base that was simulating the sort of accelerations felt within the plane during an actual flight.
That housing only removes several orders of magnitude from the equation. How the rest is removed – well Rio is keeping that fairly close to its chest.
The sensors contained within, which can measure movements as fine as 1/1000th of a hydrogen atom, have to be kept at -269C to operate properly.
The system Rio Tinto put on show in February is designated VK1b. It is about to start testing.
Rio Tinto innovation general manager Andrew Jenkin said the company hoped to take the system up to the Pilbara and try it over real exploration ground.
Jenkin said Rio had been looking for a “step change relative to existing systems”
“It will give us a better understanding of the top 1.2 kilometres of the earth’s crust,” he said.
“The big prize for us is to find the next world-class orebodies.”
This would bring a big competitive advantage.
One of the things explorers can do is merge the images from the VK1 system with other datasets such as magnetic imagery to get a better picture of what lies beneath.
The gravity gradiometer approach comes from work by Lockheed Martin in the 1960s and ‘70s.
Back then the aim was to find better ways to find Russian submarines that could be moving within nuclear missile range of the US.
Jenkin said BHP Billiton took the technology and developed Falcon, which is now in the hands of Fugro Airbone Services.
Interestingly, the plane flying Rio’s VK1 around is from Fugro.
This article first appeared in ILN's sister publication MiningNews.net.
