As a new coping mechanism with reality, Sascha has been digging into some science history and asked:
How did scientists discover plate tectonics?
Dear Sascha,
I do enjoy a good walk on the memory lane of scientific discoveries. You might know by now that great insight is gained when we look at data with fresh eyes. Hence, lots of advances in certain narrow scientific fields come from outsiders. In the story of plate tectonics you might have already heard about this meteorologist Alfred from the ’20s…
I imagine him as someone who liked puzzles and had a strong sense of pattern recognition.I think of him as someone with a great spirit of adventure, who rolled his eyes a lot. Alfred observed the continental shelves of Africa and Europe fit closely with the ones of the South and North America. After he gathers more evidence he publishes his hypothesis for continental drift, but the mechanism behind his observations was unclear. The geologists at the time were rather stiff in absorbing his ideas, as they viewed him as an outsider.
‘Wait what?! Old school geologists trying to preserve the status quo and behaving intellectually protectionist? Who would have guessed?!!‘ you might say. But, as surprising as it might be, the geology community wasn’t always as inclusive, collaborative, and forward-thinking as it clearly is today.
Fast forward to the ’50s, the Brits jumped in boats to map the bottom of the ocean (a leftover after mapping half of the world for ‘science’) and produced maps of paleomagnetic bands along mid-ocean ridges. Our beloved Marie Tharp also significantly contributed to the shift in paradigm by producing maps of the geomorphology of the ocean floor. All these observations provided evidence at the time for sea-floor spreading at mid-ocean ridges. I skipped over a lot of the evidence that was compiled in support of the idea of continental drift, and a lot of the characters at the time, but you get the point.
We are still yet to tackle our favourite key question: but how?
In fairness, the details and subtitles of the mechanism behind plate tectonics are still an active area of research. Which is a good thing, because that means I have a job. But eventually scientists realised that the plates don’t just float around passively, but they are created and consumed. Different ideas of ‘conveyor belt’ style circulations started to float within the community. Simple calculations on the relative importance of driving forces on a plate reveal that the pull from the subducting slab dominates the motion of the oceanic plate behind. From there on, hyper-specialised investigations in geochemistry, geophysics, and geodynamics keep revealing (and disagreeing) on some further intricacies on the mechanisms behind our observations…
I am sure you knew this narrative already, but now you get the sassy history of plate tectonics. It is truly a great story of human collaboration across nations and cultures, of interdisciplinary exchanges, and inclusion of minorities in science.
Yours truly,
The Sassy Scientist
P.S. You’re better off reading the Wikipedia page on this one…
