Time was born 100 years ago. Geological time, or “isotope geochronology”, to be exact. This may sound like an odd statement but 1913 was a year of two very important scientific events that gave us the tools by which we could date the age of our planet.
In 1913, Frederick Soddy’s research on the fundamentals of radioactivity led to the discovery of “isotopes.” Later that same year, Arthur Holmes published his now famous book The Age of the Earth, in which he applied this new science of radioactivity to the quantification of geologic time. Combined, these two landmark events did much to establish the field of “isotope geochronology” – the science that underpins our knowledge of the absolute age of most Earth (and extraterrestrial) materials. In celebrating the centenary, this series of blog posts (tagged #geochron100) will highlight a discipline that reflects and responds to the demands of studies ranging from the early evolution of the Solar System to our understanding of Quaternary climate change, and the 4.5 billion years in between.
INSIGHTS GAINED FROM A CENTURY OF GEOCHRONOLOGY
|Arthur Holmes (left) ca. 1910 published ‘The Age of the Earth’ in 1913. Frederick Soddy (right) in 1922 published a paper on the concept of ‘radio elements chemically non-separable’ which at the suggestion of Dr Margaret Todd, her termed ‘isotopes’.|
This convergence in 1913 of physics and geology marks the birth of isotope geochronology and while these centenaries deserve an auspicious marking, the current state of isotope geochronology also merits celebration. This month we are holding a science meeting at The Geological Society entitled ‘The first century of Isotope Geochronology: the legacy of Frederick Soddy and Arthur Holmes’, where speakers (but not including Prof Iain Stewart! ☺) from across the globe will be talking about a wide range of applications, from Mars rover exploration through to mass extinctions 200 million years ago, and recent climate change that gives us some insight into what magnitude of change we could be expecting in the coming years. Geochronology has never been more relevant. So please stop by GeoBlogy in the coming weeks/months for a look at the exciting work we’re doing and how it attempts to answers some really important questions. We’ll also try and answer why “ABSOLUTE AGES AREN’T ALWAYS EXACTLY?”, what Donald Rumsfeld has to do with dating rocks, and what we’re doing to make them better dates…
Follow Dan on Twitter @DanJCondon to hear more about his work and the upcoming meeting #wsmith13Gradstein, F., Ogg, J., Schmitz, M.S., and Ogg, G., 2012, The Geologic Time Scale 2012 2-Volume Set, 1st Edition. ISBN: 9780444594259