After recent developments, Palaeontologists can now use satellite imagery to predict and identify possible fossil sites before venturing into remote places.
Edward Davis from the Department of Earth Sciences, University of Oregon through his research showed that satellite data, especially satellite imageries can be used to reveal enormous individual fossils from the air, letting researchers in the field focus on more directed searches on the ground. Their findings were first published in the journal Geological Magazine.
Elena Ghezzo, who led the work as a postdoctoral researcher in Davis’s lab was quoted saying that the method employed here was good at identifying regions that didn’t have fossils in them.
She said that organising field work could get expensive with all the safety and security risks taken into consideration. Hence, any extra information could be useful.
The team analysed multispectral satellite imagery, which includes not just visible light, but also other wavelengths like ultraviolet and infrared.
By looking at how all these different types of light are absorbed or reflected by the landscape, researchers can pick out specific features, like fossils, from the background.
First experiment and success
Satellite data is being used to do aerial surveys of cities and track patterns of land use and for the first time it has been used to identify fossils. The researchers first tested out this hypothesis with the data collected from the Petrified Forest National Park in Arizona, USA.
The landscape which was a lush coniferous forest almost 200 million years ago, has nowturned into a desert sprinkled with fossilised logs. This data led them to create a reference map with which they compared it to the other landscape features which helped them to identify the signature in the satellite data that differentiated the fossil from the background.
If a fossil has to be identified and isolated, it should be first bigger than at least a single pixel of the image. The mineral composition of the fossil should be different from the mineral composition of the surrounding material or landscape.
Ghezzo is testing this technique out of Arizona too.
Satellite Imaging in Mongolia
In Mongolia paleontologists have turned to satellite data and, a bit closer to the land survey by drone scanning. Spectral images from Landsat and ASTER satellites now provide big-picture starting points by isolating areas where fossils might be, based on the presence of sandstone, mudstone, and shale layers deposited during the Cretaceous era (between 66 and 145 million years ago).
Once they have those general areas targeted, drones equipped with thermal, spectral, and visible-light cameras can sweep in for higher-resolution scans that can narrow the area down for actual exploration.
These new age techniques have made it more sustainable and made it possible to abandon the practices of the past, which included blowing up hillsides with dynamite which has irreparably damaged the landscape.
This helps in preserving the context in which the fossils are found.
