Imaggeo on Mondays: Using geophysical techniques to unlock the secrets of the past

Imaggeo on Mondays: Using geophysical techniques to unlock the secrets of the past

Unravelling the secrets of past civilisations is tricky at the best of times. More so if many of the records which hold clues about how communities lived, built their homes and temples, as well as how they fed themselves, were destroyed by subsequent invaders. In these instances, as Felix Rodriguez Cardozo explains in today’s post, geophysical techniques (such as Lidar, which very recently hit the headlines for contributing to discover new Cambodian temples close to Angkor Wat) can be a great asset to traditional archaeological methods.

The Yucatan Peninsula, in the southeast of Mexico, is a gorgeous place not only because of  the natural landscape but  also due to the  marvellous structures built by indigenous cultures prior to the European colonization process during the 17th Century. While it is widely known that there are several and complex indigenous structures built by different cultures along Mexico, the Yucatan’s structures blend in perfectly with the jungle, complementing rather than contrasting with the natural landscape.

Although Mexico is a country surrounded by a vast amount of natural hazards (eg. earthquakes, volcanism, hurricanes, etc.) many of the ancient structures have shown an extraordinary skill for resisting all of them. Unfortunately, during the colonization period much of the information related to the ancient cultures of México (and America in general) disappeared, including the information on the building techniques used employed to erect these incredible structures.

All was not lost!  Thanks to the archaeology and more recently, other disciplines like geophysics, we can now figure out with certain confidence the technology and building methods used  by our american ancestors.

I took this photo while conducting a geoelectric and geomagnetic survey to try and discover the foundations of the Kukulklán pyramid and learn more about its internal structure. While the photo does not show any device used during the survey, it does portray perfectly the harmony between the indigenous building and the surrounding nature, something uncommon in modern society. ,

By Félix Rodríguez Cardozo

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at




Imaggeo on Mondays: Friends in the field

Out in the field you encounter all sorts of wildlife and while mosquitos are the most frequent (and most unwelcome), they generally don’t interfere with your equipment or your data. The same can’t be said for all animals though, and many scientists have to strap their equipment out of reach, barricade it with barbed fences or place it in a relatively indestructible black box. It’s a particular problem when you need to head back to the lab or lecture theatre, and leave your equipment alone to collect precious scientific data remotely.

Animals can also cause a ruckus when you’re on site – after all, what’s more exciting than a geoscientist and their portable laboratory? This is surely the question that played on the minds of these bovine beasties before interfering with a geoelectrical survey, a method used to monitor CO2 storage and map groundwater.

Does it work? (Credit: Robert Supper, distributed via

Does it work? (Credit: Robert Supper, distributed via

While surveying groundwater in Salzburg, Austria, Robert Supper caught a crowd of curious cows taking a closer look at his equipment. “During the measurements on a meadow, we were inspected by a drove of cows, which immediately started to taste electrodes and cables,” he explains.

“On geoelectrical surveys in rural areas, we often encounter an interesting phenomenon: cows or sheep completely ignore us until we finish the installation of cables and electrodes. As soon as we are ready and want to start the measurements, they start to inspect everything, sniff on the equipment, nibble on the cables, stumble over the profile or (worst case) shit on it. If everything was tested correctly by them, they disappear,” Supper adds. Take care when you’re working in a rural area, you might just get some company.

By Sara Mynott, EGU Communications Officer

If you are pre-registered for the 2014 General Assembly (Vienna, 27 April – 2 May), you can take part in our annual photo competition! Up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at