A Geochemist in His Garden of Eden
Total Page：16
File Type：pdf, Size：1020Kb
A GEOCHEMIST IN HIS GARDEN OF EDEN WALLY BROECKER 2016 ELDIGIO PRESS Table of Contents Chapter 1 Pages Introduction ................................................................................................................. 1-13 Chapter 2 Paul Gast and Larry Kulp ......................................................................................... 14-33 Chapter 3 Phil Orr...................................................................................................................... 34-49 Chapter 4 230Th Dating .............................................................................................................. 50-61 Chapter 5 Mono Lake ................................................................................................................ 62-77 Chapter 6 Bahama Banks .......................................................................................................... 78-92 Chapter 7 Doc Ewing and his Vema ........................................................................................ 93-110 Chapter 8 Heezen and Ewing ................................................................................................ 111-121 Chapter 9 GEOSECS ............................................................................................................. 122-138 Chapter 10 The Experimental Lakes Area .............................................................................. 139-151 Table of Contents Chapter 11 Sea Salt .................................................................................................................. 152-165 Chapter 12 Redfield Ratios ...................................................................................................... 166-176 Chapter 13 The Great Ocean Conveyor .................................................................................. 177-191 Chapter 14 The Paleo Ventilation Rates .................................................................................. 192-203 Chapter 15 Calcite Dissolution ................................................................................................ 204-216 Chapter 16 Biosphere 2 ........................................................................................................... 217-230 Chapter 17 Rock Varnish ........................................................................................................ 231-241 Chapter 18 Gary Comer ........................................................................................................... 242-253 Chapter 19 Fossil Fuel CO2 ..................................................................................................... 254-267 Appendices ........................................................................................................................ 268-313 Chapter 1 Introduction Having nearly finished this book, I turn my attention to why I undertook such a project. Although there is no simple explanation, to be honest, it’s because I love to write. Having run out of new things to say, I decided to summarize what I consider to be the major scientific accomplishments of my long career. In order to maintain the reader’s interest, I have added anecdotes to illustrate the context in which my research was conducted. As someone whose career has paralleled the evolution of my field of isotope geochemistry, and of my scientific home, Lamont-Doherty, I feel an obligation to record how I fit into these two enterprises. I must caution the reader that this book is neither a review of my field nor of my institution. Rather, it is based on my recollections. As recollections often become blurred with time, I include only those things that remain clear in my mind. The first two chapters deal with three people who had enormous impacts on me. The first is Paul Gast who was assigned to be my ‘big brother’ when I entered Wheaton College. He not only got me through registration, he became a self-appointed mentor and also a friend. It was Paul who introduced me to Lamont. It was Paul who helped me through graduate school. It was Paul who joined me in directing Lamont’s geochemistry program. Were it not for cancer which snuffed out his life in his mid-forties, I’m sure that we would still be close friends and colleagues. The second person is J. Laurence (Larry) Kulp. From my arrival at Lamont on June 15, 1952, until he gave up his professorship in 1967, Larry opened one door after another, providing me with incredible opportunities. He also did wonders to build up my self-confidence. Were it not been for his persuasive skills, I would not have gotten into Columbia College without an official transcript on one day’s notice, nor would I have been appointed to the faculty immediately after receiving my PhD. Although a flawed man, as a professor, Kulp was superb. 1 The third is Phil Orr. After listening to my first-ever scientific lecture, he realized correctly that I knew little about the world around me. On the spot, he offered a remedy. He would take me on a field trip which would open my eyes to the huge opportunities were I to choose my own samples for 14C dating rather than merely providing a service by analyzing samples submitted by others. As one who had spent his entire life within 50 miles of downtown Chicago, seeing Pyramid Lake (near Reno, Nevada) and Santa Rosa Island (off Santa Barbara, California) made me realize that there were wonderful places with interesting histories awaiting study. My collaboration with Phil Orr went on for about five years. I realized along the way, however, that his motivation was not entirely pure. For by capturing me, he also captured a radiocarbon-dating laboratory at a time when there were few such facilities. Each existing lab had a large backlog and charged around 300 dollars per analysis. In connection with our research on the archeologic and climatic histories of the Pyramid Lake and Santa Rosa Island locales, Phil obtained over 100 radiocarbon ages − for free. I don’t fault him for this as I got more out of my time with him than he did from the radiocarbon dates. In addition to introducing me to the world around me, he also taught me to loosen up a bit and enjoy life. To this list of three, I must add three others: Taro Takahashi, George Kukla, and Gary Comer. One day in 1958, I walked into one of our labs and was surprised to see a young Japanese man building a vacuum system. He introduced himself as Taro Takahashi and explained that he had just returned from eight months at sea on Columbia’s research vessel Vema. Kulp had obtained International Geophysical Year (IGY) funds to measure the partial pressure of CO2 in surface water on a long traverse extending the length of the Atlantic Ocean. This program was designed to complement measurements of the atmosphere’s pCO2 content being conducted by Charles David Keeling. Kulp had latched onto Taro after he had just received a Columbia PhD in economic geology. Although Taro and I were both graduate students in the same department, he was one of the ‘Schermerhorn group’ and I was one of the ‘Lamont group’. In those days interaction between the two groups was minimal. Hence my surprise as I was unaware of his existence. Little did I realize that Taro would become a life-long companion in 2 science. Upon completing his Lamont post-doctoral fellowship, Taro served in succession as a faculty member at Alfred College, Rochester University and Queens College (in NYC). Lured by the excitement of Lamont and bored with life at Queens, Taro gave up a Distinguished Professor position there and joined Lamont as a research scientist. At 84, he remains a full-time employee of Columbia University. Our collaboration includes research on the Bahama Banks, Green Lake (near Syracuse, NY), Biosphere 2 (in Arizona), and at Mono Lake (in California). We were both heavily involved in the GEOSECS survey and, based on the data collected, we struggled to sort out Redfield ratios. I regret that a result of my deep interest in abrupt climate change and his in the ocean’s carbon cycle we have, of late, not been involved in any joint investigations. In 1969 at a meeting in Paris, I met George Kukla, a Czech who would become a life- long family friend. I was alerted that he had made an important discovery that I should know about. When I found him, I immediately realized that he was the product of a different cookie cutter. Instead of the conventional name badge, he had pinned to his lapel a corner torn off the cardboard backing of a yellow tablet. On it, written with black magic marker, it said “Kukla”. His scientific surprise was that he had put together a continental loess record which showed that, instead of the long-standing four-fold European glacial sequence, there were eight cycles since the last magnetic reversal. Further, their spacing was consistent with that for glacial to interglacial 18O cycles recorded in marine sediments. I was so impressed that two years later when Columbia announced that it could invite one scientist from an Iron-Curtain country for a two-year stay in the U.S., I nominated Kukla. He was Columbia’s choice and in 1971, he arrived at Kennedy Airport with his wife and two young children. His planned two-year stint lasted for the rest of his life. He remained a Lamont-Doherty staff scientist until his death in 2014. I could do a whole chapter on Kukla’s exploits, but will say only a few words here. George loved the woods, the wilder the better; he loved to swim, no matter how cold the water; he loved to drink and cook sausages over