lew@ihlpa.UUCP (Lew Mammel, Jr.) (12/01/86)
THE ROAD TO JARAMILLO, subtitled "Critical Years of the Revolution in Earth Science" is by William Glen and published by Stanford University Press, copyright 1982. It is a scholarly account of the scientific developments of the 1950's and 1960's which led to the formulation and acceptance of Plate Tectonics, which constitutes the revolution of the subtitle. The book starts with an account of the development and refinement of K-Ar dating which led to the ability to date young ( < 1e6 years ) rocks. This was interesting in parts, but I was frankly wondering if I was going to make the long haul as I read it. Things picked up for me when the account moved on to paleomagnetism and the establishment of a field reversal time scale ( feel your blood racing ? ) Besides the scientific excitement, there was some juicy institutional politics at the US Geological Survey and some international competition with the Australians to keep things going. Finally there was the sea floor spreading data and its link up with the reversal time scale which ushered in the new era around 1966. The main thing I learned from this book is that the reversal time scale was established independently of the sea floor magnetism data. I was very ready to be convinced of plate tectonics when reading popular articles and one look at those symmetric stripes was good enough for me. Actually, the first survey which showed the famous striped reversal patterns (if you don't know what I'm talking about, you're way behind!) was published in an article which argued strongly against sea floor spreading. It was the quantitative correspondence of the pattern with the independently established reversal time scale which was the clincher. Interestingly, the clincher came from data obtained by the Lamont Geological Observatory which was a bastion of anti-drift thinking. This fact goes a long way towards vindicating the scientific process from doubts that the Truth is subjugated to emotion and politics. Oh, before I forget, the title refers to the "Jaramillo event", a short episode of normal polarity which preceded the current epoch of normal polarity. it was one of the last refinements made to the reversal scale, and was almost simultaneously discovered in the sea floor data. Hence it stands as a linchpin holding the different data together in one unified structure. The name "Jaramillo" comes from Jaramillo Creek in new Mexico, near where the samples were collected which were used to define the event. This book is pretty dense in parts, but if you think you're interested, and if you've read the Scientific American literature, I don't think you'll be disappointed. By the way, I plan to post a note to talk.origins on the relevance of my new found knowledge to Creationism. Lew Mammel, Jr.