The Geological and Astrophysical Record; a Legacy for the Ages #58 #cong24 #legacy

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1. Understand the much longer timescale of the planet and the universe
2. Discover what kind of records are left behind from natural processes
3. Understand the use of such records
4. Realise the limited record left by human activity, even today

I am the geologist for the Joyce Country and Western Lakes aspiring UNESCO Global Geopark, of which Cong is one its communities.
I work with communities, businesses and local schools to improve the understanding of our landscape and our care for it
The Geopark’s main objective is the sustainable development of its communities for the benefit of its future generations

You can see connect via email or see his work in the Joyce Country Geopark or on Social media (Facebook, Instagram, Youtube): @JCWLGeopark

By Benjamin Thébaudeau 

Our life as human beings, the lives of our family, of our town, even the sum of all that human civilisation have ever produced or will ever produce will have only the tiniest effect on our planet and even less so on our galaxy. We live about 100 years if we are lucky and our species, homo sapiens, has existed for about 300,000 years on our planet. But our planet is 4,600 million years old and our universe 3 times that age.

The types of record found through space is essentially from to the radiation emitted from stars like our sun through their own lifecycle. The light that we can see from the closest galaxy to earth, Andromeda, is 65 million years old; the age of the dinosaurs. These radiations can tell us about the type and age of stars, the type of planetary system, the composition of the planets’ atmosphere. This has already allowed us to discover planets with similar parameters to our own that could host liquid water, a key component for the development of life as we currently understand it. All these endeavours and exploration, as when exploring the infinitely small of the particles that make up matter is of tremendous metaphysical importance and will have a lasting legacy on our understanding of the universe. It might also lead to the development of new technology or energy sources as it did with nuclear energy in the 20th century.

The types of record found in the landscape and rocks of our planet and other rocky planet of our solar system can inform us on the movement of continents, the ocean cycles, the construction of mountain ranges and eruption of massive volcanoes. It can also reveal past environments, climate patterns and habitats as well as the evolution of life. It allows us to recognise Mars as an analogue of Earth in its early days, frozen in time due to the lack of plate tectonics and its light atmosphere. Closer to home, we have extensive records of ancient supercontinents, of a time when the planet was covered entirely in ice (snowball earth), and it reminds us of an ancient ocean (Iapetus) that separated Ireland in 2 up to 420 million years ago and of the connections we have with northeast America, the Atlantic ocean just separating us from our previous neighbour in the last 100 million years. More importantly for our landscape, it reminds us of a time not so long ago (16,000 years) when Ireland was still under ice sheets that shaped the valleys and plains, hills and mountains and the numerous lakes they left behind. Understanding these records is vital to the management of our mineral resources including our water.

When it comes to the types of record we as humans leave behind, we can look at Archaeology and the science of Taphonomy or decay that tell us what happens to various material (organic or inorganic) when they die or are abandoned. Our hunter/gatherer ancestors left very little traces behind beyond the shaped stone tools they used and the evidence of disappearance of ancient megafauna they likely caused. Since the advent of agriculture, settlement buildings and land management have started to leave traces we can recognise in the sediments and soils. The expansion of crop fields and pastures has meant a reduction in the amount of wild forest and a change of habitats detectable in the record. Today, our plastic rubbish accumulates as a new layer in the sediment record while radioactive isotopes released from nuclear explosions appear as clear markers of our modern activity, notwithstanding the elevated carbon dioxide found in our atmosphere that will be detectable for thousands of years to come. In the end the planet and universe will be fine, but what will we have left behind if anything ?