Boom: scientists confirm one of world’s oldest, demonstrably eye-witnessed volcanic shows
Recently, an international team of volcanologists married 21st century research with Bronze Aged footsteps and cave paintings from Turkey’s Kula UNESCO Geopark to confirm the oldest, demonstrable* human sighting of a volcanic eruption in the world.
This fascinating tale has reached international audiences via popular online media outlets in the last week. Here we dig a little deeper with Curtin University researcher, Dr Martin Danišík about the innovative rock age dating methods behind it.
Thank you Jo! It was an honour and a real challenge to work on this exciting project.
It was also great that our work caught the attention of popular science media, mostly in countries
that have active volcanoes and a keen national interest in volcanology. But to our surprise, we also
made it onto Forbes.com — in the ‘Innovation’ not ‘Billionaires’ section!
Can you tell us briefly about your research question, methods and findings?
Our team has been working on volcanic complexes in Turkey for years. In this study, we wanted to figure out the age of some famous prehistoric human footprints, known as ‘Kula Footprints’ that are preserved in a volcanic ash layer near the Çakallar volcano. They have been dated previously using older dating techniques, but we wanted to see what our newer, more accurate techniques might reveal.
But here’s the interesting bit: the footprints are located just two kilometres away from an old rock painting that has been interpreted as depicting an erupting volcano. The age of the painting has previously shown to be a different age to the footprints.
But with a new footprint age, could we prove that early humans who made them also have witnessed and recorded a rather spectacular volcanic eruption nearby? If so, this would confirm the oldest eye-witnessed volcanic eruption in the world!
We found the age of the volcanic ash is ~4,700 years old, which is almost 250,000 younger than the original date and ~5,000 years younger than the most recent date. Our results place the prehistoric footprints into Bronze Age and confirmed they belong to Homo Sapiens, not to Homo Neanderthalensis
as previously thought.
Amazing science! Stepping back, when did you become interested in young volcanic geochronology?
I was exposed to age dating of young volcanoes about 10 years ago, when we had a project in picturesque Cappadocia looking at youngest volcanic phases in the area, and Helium dating was that new fancy method that enabled geologists to date many of the processes and events that could not be previously dated by existing tools.
We figured out that with some tweaks the Helium dating method can work really well on some young volcanic rocks. This opened up many exciting opportunities as with this novel approach we could finally measure eruptions ages for very young volcanoes — I’m talking down to a few thousands of years — which had not been really achievable before.
After nailing the new technique in the lab and running some successful proof-of-concept studies, we expanded our research scope to other interesting young volcanoes in Turkey, focusing mostly on understanding their evolution, tempo of their eruptions and potential hazards to human society.
And then in 2014, kind of inadvertently, we stepped into the archaeology field when we contributed to a debate about the world’s oldest map and one of the oldest paintings of a volcanic eruption, which were depicted on a mural found in one of the oldest settlement/proto-city Çatalhöyük dated back to ~6,600 BCE.
Geology meets anthropology, fascinating! How did this earlier work inform your latest project?
Yes! I personally took this project as an exciting challenge: in the 2014 Çatalhöyük study I measured eruption age of ~9,000 years in our lab, which back then was one of the youngest credible eruption ages measured by Helium method and the whole process really pushed the methodology to its analytical limits.
In Kula study, the initial results from cosmogenic chlorine indicated even younger eruption ages can be expected — challenge accepted I thought. And thanks to some favourable circumstances related to sample quality and improvements on instrumental and analytical fronts, our Helium method turned out to work pretty well as we measured the same ages as the cosmogenic chlorine method run in parallel in a blind experiment. Once we nailed the age of those footprints, it was a matter of writing an interesting story with some archaeological spin and find a journal that would be interested in publishing it.
How do you date young volcanic eruptions?
We date young volcanic eruptions using Zircon Double Dating (ZDD) whereby we measure time recorded by two different internal ‘clocks’ of zircon which have been recording different geological events. The first ‘clock’ records the time of zircon growth in magma chamber and can be determined from uranium, thorium and lead isotopes.
The second ‘clock’ records the time when zircon was erupted to Earth surface and be calculated from uranium, thorium isotopes and helium gas stored in the crystals. Dated crystals are usually tiny (the size of a sand grain) and isotopic abundances are very low, and can be measured only on specialist mass-spectrometry instruments.
These, together with a world class collection of analytical instruments for geochronology and material characterisation are available for researchers to use at the John de Laeter (JDLC) at Curtin University, thanks to generous support from AuScope and NCRIS.
What might it have been like to have witnessed the eruption?
Difficult to tell, probably very special and hopefully not too scary!
Distance and orientation of the footprints suggest that individuals were walking rather than running from west to east towards the Çakallar cone, so maybe they were just curious to see what happened with the volcano after its initial outburst and ash deposition.
What can visitors to the Kula UNESCO Geopark expect to see today?
Aside from the Çakallar volcanic cone, the Kula Geopark offers fascinating volcanic landscapes and perfectly exposed volcanic structures — many other cones, craters, lava caves and lava tubes or basalt columns, which are spectacular even for non-volcanologists.
In fact, Kula was recognized as a special place a long time ago - already Strabo (Greek geographer, philosopher and historian; 64 or 63 BC – 24 AD) mentioned Kula in his book “Geographica” (a.k.a. Encyclopedia of geographical knowledge) and named it as “Katakekaumene” (burned lands or fire-born), referring to the pitch-black color of the lava. Don’t miss the prehistoric footprints and the rock painting.
What’s next for you?
Right now I am getting ready for a field work on Jeju Volcanic Island in South Korea, which has been quite active for the last 900,000 years. Some of the rocks contain beautiful zircon crystals that will hopefully help us to constrain timing of latest eruptions. Next I want to date some volcanic zircons from Kamchatka because we know very little about eruptive history of this region as it wasn’t accessible for a long time.
And my long term perspective: I want to pursue my research interests in volcanic geochronology, including continuing my ongoing projects on young volcanic systems around Pacific margin. I also want to improve and push the limits of ZDD methodology, explore new avenues of dating geological records, and be ready to start new projects on important, unexplored volcanoes in exciting corners of our planet!
This interview was taken by Jo Condon from AuScope with Dr Martin Danišík of Curtin University. Martin’s research was enabled in part by AuScope-funded research instruments at the John de Laeter Centre.
This new research confirms the oldest, *demonstrable eye-witnessed volcanic show by geochronological techniques and graphical recording, rather than oral histories which have been recorded earlier (4300 —> 9000) in Australia.