The brand-new research study analyzed the impacts of worldwide tectonic forces on these volcanic eruptions spanning the last billion years. The findings have been released in the journal Nature.
Jwaneng Diamond Mine, Botswana. Credit: Professor Tom Gernon, University of Southampton
Southampton researchers collaborated with colleagues from the University of Birmingham, the University of Potsdam, the GFZ German Research Centre for Geosciences, Portland State University, Macquarie University, the University of Leeds, the University of Florence, and Queens University, Ontario.
Tom Gernon, Professor of Earth Science and Principal Research Fellow at the University of Southampton, and lead author of the study, stated: “The pattern of diamond eruptions is cyclical, mimicking the rhythm of the supercontinents, which put together and break up in a duplicated pattern over time. But previously we didnt understand what process causes diamonds to all of a sudden appear, having invested millions– or billions– of years stashed away 150 kilometers below the Earths surface.”
To resolve this question, the team utilized analytical analysis, consisting of maker knowing, to forensically take a look at the link in between continental break up and kimberlite volcanism. The outcomes revealed the eruptions of many kimberlite volcanoes occurred 20 to 30 million years after the tectonic separation of Earths continents.
Diamond in its host rock (kimberlite). Credit: Dr. Richard Brown, University of Durham
Dr. Thea Hincks, Senior Research Fellow at the University of Southampton, stated: “Using geospatial analysis, we found that kimberlite eruptions tend to slowly move from the continental edges to the interiors gradually at rates that are constant across the continents.”
Geological processes
This discovery prompted the scientists to explore what geological process could drive this pattern. They discovered that the Earths mantle– the convecting layer in between the crust and core– is disrupted by rifting (or extending) of the crust, even thousands of kilometers away.
Dr Stephen Jones, Associate Professor in Earth Systems at the University of Birmingham, and research study co-author said: “We discovered that a domino result can describe how continental breakup causes the development of kimberlite magma. Throughout rifting, a small patch of the continental root is interfered with and sinks into the mantle below, triggering a chain of comparable flow patterns underneath the nearby continent.”
Dr. Sascha Brune, Head of the Geodynamic Modelling Section at GFZ Potsdam, and a co-author on the research study, ran simulations to examine how this process unfolds. He stated: “While sweeping along the continental root, these disruptive flows eliminate a significant quantity of rock, 10s of kilometers thick, from the base of the continental plate.”
Venetia Diamond Mine, South Africa. Credit: Professor Tom Gernon, University of Southampton
The common migration rates estimated in designs matched what the researchers observed from kimberlite records.
” Remarkably, this process unites the necessary active ingredients in the best quantities to activate just enough melting to generate kimberlites,” included Dr Gernon.
The teams research could be utilized to recognize the possible areas and timings of previous volcanic eruptions tied to this procedure, using valuable insights that could enable the discovery of diamond deposits in the future.
Teacher Gernon, who was recently awarded a significant humanitarian grant from the WoodNext Foundation to study the factors contributing to global cooling gradually, said the study likewise sheds light on how procedures deep within the Earth control those at the surface: “Breakup not just rearranges the mantle, but might also profoundly effect Earths surface area environment and environment, so diamonds may be just a part of the story.”
Referral: “Rift-induced disruption of cratonic keels drives kimberlite volcanism” by Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin R. Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. OReilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith and Anne Glerum, 26 July 2023, Nature.DOI: 10.1038/ s41586-023-06193-3.
Macle twin diamond discovered in Arctic Canada. Credit: Professor Tom Gernon, University of Southampton
New findings hold the prospective to stimulate future diamond discoveries.
An international team of researchers, led by the University of Southampton, has discovered that the break up of tectonic plates is the primary driving force behind the generation and eruption of diamond-rich magmas from deep inside the Earth.
This insight could considerably influence the trajectory of the diamond exploration industry, directing efforts to places where diamonds are most probable.
Diamonds, which form under terrific pressures at depth, are hundreds of millions, or even billions, of years old. Kimberlites are discovered in the oldest, thickest, greatest parts of continents– most significantly in South Africa, home to the diamond rush of the late 19th century.
