Annals of the Former World
I have just finished reading 'Annals of the Former World' by John McPhee. It is about a 20 year journey along Interstate 80 which roughly spans the center of the U.S. from New York to San Francisco, but also a 4600 million year journey through geologic time. For some time now I have been so involved in the minutia of modeling hydrocarbon signatures in seismic data that I had forgotten what drew me to geology in the first place. When I started college in the mid-70's the Theory of Plate Tectonics was just beginning to be widely accepted in the geologic community. The Theory of Plate Tectonics was as great a breakthrough to geology as the Theory of Relativity was to physics. It profoundly changed our understanding of the transient nature of the surface of our planet.
I had not been keeping up with the latest developments. That new radioactive dating techniques were expanding our ability to more accurately and precisely map the ancient history of continents prior to the Cambrian Explosion (when life seemed to burst forth in the fossil record) 600 million years ago. It allowed the reconstruction of the supercontinent before Pangea called Rodinia in Pre-Cambrian time. I didn't know that Mars and some of Jupiter's moons show signs of active plate movement in their past. And progress has been made on understanding some of the drive mechanisms for plate techtonics--that plates are not pushed apart at the mid-ocean ridges, but dragged apart at the subduction zones.
Mostly though I was able to regain that little bit of a glimpse of understanding of the vastness of geologic time. If one were to stretch their arms as wide as they could and that were the extent of Earth's history, a snip of a fingernail would erase the history of mankind. It makes one humble.
I had not been keeping up with the latest developments. That new radioactive dating techniques were expanding our ability to more accurately and precisely map the ancient history of continents prior to the Cambrian Explosion (when life seemed to burst forth in the fossil record) 600 million years ago. It allowed the reconstruction of the supercontinent before Pangea called Rodinia in Pre-Cambrian time. I didn't know that Mars and some of Jupiter's moons show signs of active plate movement in their past. And progress has been made on understanding some of the drive mechanisms for plate techtonics--that plates are not pushed apart at the mid-ocean ridges, but dragged apart at the subduction zones.
Mostly though I was able to regain that little bit of a glimpse of understanding of the vastness of geologic time. If one were to stretch their arms as wide as they could and that were the extent of Earth's history, a snip of a fingernail would erase the history of mankind. It makes one humble.