In a Finnish outcrop nestled between some of Northern Europes earliest mountains, scientists have discovered traces of a formerly concealed part of Earths crust that points more than three billion years back in time and north towards Greenland.These traces were found in the mineral zircon, which after chemical analyses, showed to scientists from the Department of Geosciences and Natural Resource Management that the “foundation” upon which Denmark and Scandinavia rest, was most likely born from Greenland around 3.75 billion years back. This discovery sheds light on the formation of continents and the distinct existence of life on Earth compared to other worlds in our solar system.In a secluded Finnish outcrop, tucked away among some of the oldest mountains in Northern Europe, scientists have actually revealed have actually discovered traces of a previously concealed part of Earths crust that points more than 3 billion years back in time and north towards Greenland.These traces were discovered in the mineral zircon, which after chemical analyses, indicated to scientists from the Department of Geosciences and Natural Resource Management that the “foundation” upon which Denmark and Scandinavia rest, was most likely born from Greenland around 3.75 billion years ago.The zircon crystals we discovered in river sand and rocks from Finland have signatures that point towards them being much older than anything ever found in Scandinavia, while matching the age of Greenlandic rock samples. And, proof of liquid water and a granite crust are essential factors when trying to determine habitable exoplanets and the possibility of life beyond Earth,” explains Andreas Petersson.Continents are the key to lifeThe brand-new study includes pieces to a primordial continental puzzle that started long in the past life on Earth really blossomed, but which has actually mainly paved the way for both animal and human life. Continents affect both ocean currents and climate, which are important for life on Earth,” says Andreas Petersson.Furthermore, the new research study contributes to a growing number of research studies which decline the methods utilized therefore far to compute how continents have grown– specifically throughout the first billion years of Earths history.
In a Finnish outcrop nestled in between a few of Northern Europes oldest mountains, scientists have discovered traces of a previously concealed part of Earths crust that points more than three billion years back in time and north towards Greenland.These traces were found in the mineral zircon, which after chemical analyses, indicated to scientists from the Department of Geosciences and Natural Resource Management that the “structure” upon which Denmark and Scandinavia rest, was probably born from Greenland roughly 3.75 billion years back. Credit: Andreas PeterssonA brand-new geological study from the University of Copenhagen has revealed that the earliest Scandinavian bedrock came from Greenland. This discovery clarifies the formation of continents and the unique existence of life in the world compared to other planets in our solar system.In a secluded Finnish outcrop, tucked away among a few of the oldest mountains in Northern Europe, researchers have discovered have found traces of a previously concealed part of Earths crust that points more than 3 billion years back in time and north towards Greenland.These traces were found in the mineral zircon, which after chemical analyses, showed to researchers from the Department of Geosciences and Natural Resource Management that the “foundation” upon which Denmark and Scandinavia rest, was probably born from Greenland approximately 3.75 billion years ago.The zircon crystals we discovered in river sand and rocks from Finland have signatures that point towards them being much older than anything ever found in Scandinavia, while matching the age of Greenlandic rock samples. At the same time, the results of three independent isotope analyses validate that Scandinavias bedrock was more than likely connected to Greenland. Credit: Andreas Petersson” Our information suggest that the earliest part of Earths crust beneath Scandinavia comes from Greenland and has to do with 250 million years older than we previously believed,” states Professor Tod Waight, a geologist at the Department of Geosciences and Natural Resource Management.The researchers study of the zircon showed that, in numerous methods, its chemical finger print matches those of a few of the earliest rocks on the world discovered in West Greenlands North Atlantic Craton.” The zircon crystals we found in river sand and rocks from Finland have signatures that point towards them being much older than anything ever discovered in Scandinavia, while matching the age of Greenlandic rock samples. At the same time, the results of three independent isotope analyses confirm that Scandinavias bedrock was most likely connected to Greenland,” says Department of Geosciences and Natural Resource Management researcher Andreas Petersson.A water world without oxygenDenmark, Sweden, Norway, and Finland rest atop a part of Earths crust referred to as the Fennoscandian Shield, or the Baltic Shield. The scientists think that it broke away from Greenland as a “seed” and shifted for numerous countless years up until it “took root” where Finland is today.Here, the plate grew as new geological product built up around it, until it became Scandinavia. At the time of the crusts detachment from Greenland, the world looked extremely different than today.The researchers analysed zircons from modern river sand and rock samples from the remote Pudasjärvi and Suomujärvi regions of Finland, whose geological origins have actually been little studied.The zircon crystals discovered in the Finnish river sand initially crystallized in granitic lavas deep within the crust. These granites were then lifted to the surface and deteriorated to ultimately form sand. Credit: Tod Waight” Earth was most likely a watery planet, like in the motion picture Waterworld, but without any oxygen in the atmosphere and without emerging crust. Because thats so far back in time, we cant actually be sure about what it actually looked like,” says Tod Waight.According to the researchers, the reality that Earth even has a continental crust composed of granite is rather special when they look out into space and compare it with other planets in our stellar community.” This is distinct in our solar system. And, evidence of liquid water and a granite crust are essential aspects when trying to identify habitable exoplanets and the possibility of life beyond Earth,” explains Andreas Petersson.Continents are the key to lifeThe new research study includes pieces to a primordial continental puzzle that started long previously life on Earth really progressed, however which has largely led the way for both animal and human life.” Understanding how continents formed assists us understand why ours is the only world in the solar system with life on it. Because without fixed continents and water in between them, we would not be here. Undoubtedly, continents affect both ocean currents and climate, which are vital for life on Earth,” says Andreas Petersson.Furthermore, the new research study contributes to a growing number of studies which turn down the ways utilized so far to compute how continents have grown– especially throughout the first billion years of Earths history.” The most typically utilized designs assume that Earths continental crust began to form when the planet was formed, about 4.6 billion years earlier. Instead, our and a number of other recent studies recommend that the chemical signatures revealing development of the continental crust can just be determined about a billion years later on. This indicates that we may require to revise much of what we believed about how early continents progressed,” says Professor Waight.At the same time, the results of the research study contribute to previous research that found comparable “seeds” from ancient crusts in other parts of the world.” Our study supplies us with another important hint in the mystery of how continents formed and spread across Earth– specifically when it comes to the Fennoscandian Shield. There is still plenty that we dont understand. In Australia, South Africa, and India, for instance, similar seeds have actually been discovered, however were unsure of whether they all come from the exact same “birthplace”, or whether they stemmed independently of one another in numerous put on Earth. This is something that we would like to examine more using the method we utilized in this study,” concludes Professor Waight.Reference: “An Eoarchean continental nucleus for the Fennoscandian Shield and a link to the North Atlantic craton” by Andreas Petersson, Tod Waight, Anthony I.S. Kemp, Martin. J. Whitehouse and John W. Valley, 28 December 2023, Geology.DOI: 10.1130/ G51658.1.
