|What is the color of my hair:||Strawberry-blond|
Not a MyNAP member yet? Register for a free to start saving and receiving special member only perks. Clair Patterson was an energetic, innovative, determined scientist whose pioneering work stretched across an unusual of sub-disciplines, including archeology, meteorology, oceanography, and environmental science—besides chemistry and geology.
Contact information and links
He is best known for his determination of the age of the Earth. That was possible only after he had spent some five years establishing methods for the separation and isotopic analysis of lead at microgram and sub-microgram levels.
His techniques opened a new field in lead isotope geochemistry for terrestrial as well as for planetary studies. Whereas terrestrial lead isotope data had been based entirely on galena ore samples, isotopes could finally be measured on ordinary igneous rocks and sediments, greatly expanding the utility of the technique.
While subsequently applying the methodology to ocean sediments, he came to the conclusion that the input of lead into the oceans was much greater than the removal of lead to sediments, because human activities were polluting the environment with unprecedented, possibly dangerous, levels of lead. Then followed years of study and debate involving him and other investigators and politicians over control of lead in the environment.
A acmarket.website site
In the end, his basic views. Thus, in addition to measuring the age of the Earth and ificantly expanding the field of lead isotope geochemistry, Patterson applied his scientific expertise to create a healthier environment rock dating Paterson society. His father, whom he describes as "a contentious intellectual Scot," was a postal worker. His mother was interested in education and served on the school board. A chemistry set, which she gave him at an early age, seems to have started a lifelong attraction to chemistry.
He attended a small high school with fewer than students, and later graduated from Grinnell College with an A. There he met his wife-to-be Lorna McCleary. They moved to the University of Iowa for graduate work, where Pat did an M. After several months there, he decided to enlist in the army, but the draft board rejected him because of his high security rating and sent him back to the University of Chicago. At Oak Ridge, Patterson worked in the U electromagnetic separation plant and became acquainted with mass spectrometers.
After the war it was natural for him to return to the University of Chicago to continue his education. Laurie obtained a position as research infrared spectroscopist at the Illinois Institute of Technology to support him and their family while he pursued his Ph. In those days a large of scientists had left various wartime activities and had assembled at the University of Chicago.
Mark Inghram, a mass spectrometer expert in the physics department, also played a critical role in new isotope work that would create new dimensions in geochemistry. The university had created a truly exciting intellectual environment, which probably few, possibly none, of the graduate students recognized at the time.
Harrison Brown had become interested in meteorites, and started a program to measure trace element abundances by the new analytical techniques that were developed during the war years. The meteorite data would serve to define elemental abundances in the solar system, which, among other applications, could be used to develop models for the formation of the elements.
The first project with Edward Goldberg, measuring gallium in iron meteorites by neutron activation, was already well along when Patterson and I came on board. The plan was for Patterson to measure the isotopic composition and concentration of small quantities of lead by developing new mass spectrometric techniques, while I was to measure uranium by alpha counting.
I finally also ended up using the mass spectrometer with isotope dilution instead of alpha counting. In part, our projects would attempt to verify several trace element abundances then prevalent in the meteorite literature which appeared and turned out to be erroneous, but Harrison also had the idea that lead isotope data from iron meteorites might reveal the isotopic composition of lead when the solar system first formed. He reasoned that the uranium concentrations in iron meteorites would probably be negligible compared to lead concentrations, so that the initial lead isotope ratios would be preserved.
That was the goal when Patterson began his. Patterson started lead measurements in in a very dusty laboratory in Kent Hall, one of the oldest buildings on campus. In retrospect it was an extremely unfavorable environment for lead work. None of the modern techniques, rock dating Paterson as laminar flow filtered air, sub-boiling distillation of liquid reagents, and Teflon containers were available in those days. In spite of those handicaps, Patterson was able to attain processing blanks of circa 0.
His dissertation in did not report lead analyses from meteorites; instead it gave lead isotopic compositions for minerals separated from a billion-year-old Precambrian granite. On a visit to the U. Geological Survey in Washington D. Larsen, Jr. Alpha counting was used as a measure of the uranium and thorium content; lead, which was assumed to be entirely radiogenic produced by the decay of uranium and thoriumwas determined by emission spectroscopy.
Despite several obvious disadvantages, the method seemed to give reasonable dates on many rocks. Brown saw that the work of Patterson and me would eliminate those problems, so rock dating Paterson arranged to study one of Larsen's rocks. We finally obtained lead and uranium data on all of the major, and several of the accessory, minerals from the rock. Particularly important was the highly radiogenic lead found in zircon, which showed that a common accessory mineral in granites could be used for measuring accurate ages.
As it happened, the zircon yielded nearly concordant uranium-lead ages, although that did not turn out later to be true. In any case, that promising start opened up a new field of dating for geologists, and has led to hundreds of age determinations on zircon. In parallel with the lead work, Patterson participated in an experiment to determine the branching ratio for the decay of 40 K to 40 Ar and 40 Ca.
Although the decay constant for beta decay to 40 Ca was well established, there was much uncertainty in the constant for decay to 40 Ar by K electron capture. This led Mark Inghram and Harrison Brown to plan a cooperative study to measure the branching ratio by determining the radiogenic 40 Ar and 40 Ca in a million-year-old KCl crystal sylvite.
Kimberley rock art dating project
After graduation, Patterson stayed on with Brown at Chicago in a postdoctoral role to continue the quest toward their still unmet meteorite age goal. He obtained much cleaner laboratory facilities in the new Institute for Nuclear Studies building, where he worked on improvement of analytical techniques. However, after a year this was interrupted when Brown accepted a faculty appointment at the California Institute of Technology.
Patterson accompanied him there and built facilities that set new standards for low-level lead work. By he was finally able to carry out the definitive study, using the troilite sulfide phase of the Canyon Diablo iron meteorite to measure the isotopic composition of primordial lead, from which he determined an age for the Earth.
The chemical separation was done at CalTech, and the mass spectrometer measurements were still made at the University of Chicago in Mark Inghram's laboratory. Harrison Brown's suspicion was finally confirmed! The answer turned out to be 4. The new age was substantially older than the commonly. Patterson's reactions on being the first person to know the age of the Earth are interesting and worthy of note.
He wrote, 1. True scientific discovery renders the brain incapable at such moments of shouting vigorously to the world ''Look at what I've done!
Geoscience australia paterson projects
Now I will reap the benefits of recognition and wealth. There "we" refers to what Patterson calls "the generations-old community of scientific minds. To him it must have been an exercise in improving the state of the "community of scientific minds.
The age that Patterson derived has stood the test of time, and is still the quoted value forty-four years later. In the meantime, there have been small changes in the accepted values for the uranium decay constants, improvements in chemical and mass spectrometric techniques, and a better understanding of the physical processes taking place in the early solar system and Earth formation, but these have not substantially changed the age Patterson first gave to us.
Some textbooks have given diagrams showing that the logarithm of the supposed age of the Earth plotted against the year in which the ages appeared approximated a straight line, but Patterson's work has finally capped that trend. Patterson next focused on dating meteorites directly instead of inferring their ages from the Canyon Diablo troilite initial lead ratios. He did this by measuring lead isotope ratios in two stone meteorites with spherical chondrules chondrites and a second stone without chondrules achon.
A colleague, Leon Silver, had recommended the achondrite because of its freshness and evolved petrologic appearance. They also fit the 4. The meteorite work led indirectly to his second major scientific accomplishment.
The new ability to isolate microgram quantities of lead from ordinary rocks and determine its isotopic composition had opened for the first time the path for measuring lead isotopes in common geological samples, such as granites, basalts, and sediments. That led him to start lead isotope tracer studies as a tool for unraveling the geochemical evolution of the Earth.
As part of that project he set out to obtain better data for the isotopic composition of "modern terrestrial lead" by measuring the isotopic composition of lead in ocean sediments.
By Tsaihwa J. Chow and Patterson reported the first in an encyclopedic publication that initiated Patterson's concern with anthropogenic lead pollution, which was to occupy much of his attention for the remainder of his scientific career. The isotope data revealed interesting patterns for Atlantic and Pacific Ocean le that could be related to the differences in the ages and compositions of the landmasses draining into those oceans.
However, in studying the balance between input and removal of lead in the oceans, the. Thus, the geochemical cycle for lead appeared to be badly out of balance.
In addition to reading online, this title is available in these formats:
The authors noted that their calculations were provisional; the analytical data were scarce or of poor precision in many cases, however this was the seminal study that started Patterson's investigations into the lead pollution problem. The limitations in the analytical data on which many of the conclusions in the paper were based led Patterson to start new investigations to attack the problem. In he published a report with Mitsunobu Tatsumoto showing that deep ocean water contained 3 to 10 times less lead than surface water, the reverse of the trend for most elements e.