48th Atlantic Micromounters' Conference: Saturday April 2, 2022 - 1pm on Zoom EDT
Saturday April 2 - Speakers / Topics 1 & 3pm ET
1pm - Dr. Robert Hazen, Senior Scientist at the Carnegie Institution for Science and Robinson Professor of Earth Science, Emeritus, at George Mason University
Topic: Mineral Informatics: Visualizing the amazing mineral kingdom
3pm - Alec Brenner, fifth year Harvard PhD student
Topic: Little magnets, big geodynamics: Micromineralogy as a tool for studying Earth’s magnetic field and tectonics in deep geologic time
Speaker Abstracts/ Biographies
Dr. Robert Hazen - Abstract: “Every mineral specimen holds incredible amounts of information – each mineral is a time capsule waiting to be opened. “Mineral informatics” is an emerging approach to understanding the story of Earth, which is a 4.5-billion-year saga of dramatic transformations, driven by physical, chemical, and biological processes. Sequential changes of terrestrial planets and moons are best preserved in their rich mineral record. Earth's “mineral evolution,” began with a score of different mineral species that formed in the cooling envelopes of exploding stars. Dust and gas from those stars clumped together to form our stellar nebula, the nebula formed the Sun and countless planetesimals, and alteration of planetesimals by water and heat resulted in the 300 minerals found today in meteorites that fall to Earth. Earth’s evolution progressed by a sequence of chemical and physical processes, which ultimately led to the origin-of-life. Once life emerged, mineralogy and biology co-evolved, as changes in the chemistry of oceans, the atmosphere, and the crust dramatically increased Earth’s mineral diversity to the more than 5700 species known today."
Dr. Hazen's Biography - "Robert M. Hazen, Senior Scientist at the Carnegie Institution for Science and Robinson Professor of Earth Science, Emeritus, at George Mason University, received degrees in geology from MIT and Harvard. Author of more than 450 articles and 25 books on science, history, and music, his recent book The Story of Earth (Viking-Penguin) was finalist in the Royal Society and Phi Beta Kappa science book competitions. Hazen has been recipient of numerous awards, including the 2021 IMA Medal, the 2016 Roebling Medal of the Mineralogical Society of America, and the 2012 Virginia Outstanding Faculty Award. In 2020 he was elected Foreign Member of the Russian National Academy of Sciences. The biomineral “hazenite” was named in his honor. Since 2008, Hazen and his colleagues have explored “mineral evolution” and “mineral ecology”—new approaches that exploit large and growing mineral data resources to understand the co-evolution of the geosphere and biosphere. In October 2016 Hazen retired from a 40-year career as a professional trumpeter, during which he performed with numerous ensembles including the Metropolitan Opera, Royal Ballet, and National Symphony."
Alec Brenner - Abstract: Many iron oxide and sulfide minerals are ferromagnetic, including magnetite, hematite, and pyrrhotite. This means that these minerals become magnetized when they form in a magnetic field and can then retain their magnetization when the field is changed or removed. As a result, these minerals - and the rocks they occur in - can preserve records of the ambient magnetic field in deep geologic time. Paleomagnetists study these ancient magnetic signals to understand the evolution of Earth's magnetic field and the motions of tectonic plates through it, among other applications.
However, Earth's oldest preserved rocks have traditionally been considered inappropriate for paleomagnetic work. Billions of years of metamorphism, deformation, and tectonic events have erased most of their magnetic records, obscuring our view of early Earth's magnetic field and plate tectonics. This is especially true before about 3 billion years ago, coinciding with the evolution of some of the first life on Earth.
Fortuitously, my work in the lab of Prof. Roger Fu has identified volcanic rocks in Western Australia that retained 3.2-billion-year-old magnetizations. I will discuss our data from these rocks, which document the oldest described reversal of Earth's magnetic field, as well as large plate motions of the underlying of crust. Of particular interest to micromounters are our magnetic microscopy observations. Using a state-of-the-art magnetic microscope developed by Prof. Fu, we have directly mapped the magnetized signals in our rocks at micron scale (0.001 mm). By closely examining the textures and mineral populations associated with the magnetic minerals in our samples, we have established that they became magnetized when the rocks were chemically altered by hot seawater during a hydrothermal event 3.2 billion years ago. This alteration removed original magnetic minerals and grew new ones via a complex sequence of co-occurring metamorphic reactions. Raman spectroscopy, electron microscopy, traditional petrographic analyses, and in-situ geochronology further constrain the timing and thermal conditions of this alteration. Our newfound understanding of how these ancient rocks became magnetized paves the way for new studies of Earth’s earliest magnetic record.
Brenner's Biography: Alec is a fervent rockhound and native of McLean. He is also a fifth-year PhD student at Harvard University, where his research focuses on the mineralogical basis of magnetism preserved in Earth’s oldest rocks. This in turn informs his reconstructions of tectonics, core circulation, and surface processes on the early Earth. This research has thus far included field work in rocks about three billion years old in Australia, South Africa, and Minnesota.
Alec first got interested in minerals after finding prehnite from the Vulcan Manassas Quarry in the gravel of his elementary school parking lot. He continued rockhounding and fossil collecting with the Northern Virginia Mineral Club, which he joined in 2007. While attending Thomas Jefferson High School for Science and Technology (TJHSST), Alec’s interests matured into geoscience research. This included collaborations with micropaleontologists and planetary scientists at the US Geological Survey, The Smithsonian Institution, and NASA’s Goddard Space Flight Center. He attended the California Institute of Technology (Caltech) for his undergraduate studies, earning a BS in Geology in 2017. There, he found his true loves, including his now-wife Netgie and his current specializations in paleomagnetism, deep-time Earth history, and mineralogy.
Alec currently lives in Arlington, Massachusetts, where he hikes atop the rocks of the Avalonian Terrane, counts the days until he can resume field work in Australia (pictured), and dotes on his tabby cat Sienna. A special thanks to Prof. Roger Fu, Alec’s academic advisor at Harvard’s Paleomagnetics Lab, for funding and contributing his expert guidance to the work presented here. Alec also thanks his parents Sara and Paul Brenner, who tirelessly supported his odd fascinations with rocks and drove him to so many NVMC meetings and field trips as a kid.
1pm - Dr. Robert Hazen, Senior Scientist at the Carnegie Institution for Science and Robinson Professor of Earth Science, Emeritus, at George Mason University
Topic: Mineral Informatics: Visualizing the amazing mineral kingdom
3pm - Alec Brenner, fifth year Harvard PhD student
Topic: Little magnets, big geodynamics: Micromineralogy as a tool for studying Earth’s magnetic field and tectonics in deep geologic time
Speaker Abstracts/ Biographies
Dr. Robert Hazen - Abstract: “Every mineral specimen holds incredible amounts of information – each mineral is a time capsule waiting to be opened. “Mineral informatics” is an emerging approach to understanding the story of Earth, which is a 4.5-billion-year saga of dramatic transformations, driven by physical, chemical, and biological processes. Sequential changes of terrestrial planets and moons are best preserved in their rich mineral record. Earth's “mineral evolution,” began with a score of different mineral species that formed in the cooling envelopes of exploding stars. Dust and gas from those stars clumped together to form our stellar nebula, the nebula formed the Sun and countless planetesimals, and alteration of planetesimals by water and heat resulted in the 300 minerals found today in meteorites that fall to Earth. Earth’s evolution progressed by a sequence of chemical and physical processes, which ultimately led to the origin-of-life. Once life emerged, mineralogy and biology co-evolved, as changes in the chemistry of oceans, the atmosphere, and the crust dramatically increased Earth’s mineral diversity to the more than 5700 species known today."
Dr. Hazen's Biography - "Robert M. Hazen, Senior Scientist at the Carnegie Institution for Science and Robinson Professor of Earth Science, Emeritus, at George Mason University, received degrees in geology from MIT and Harvard. Author of more than 450 articles and 25 books on science, history, and music, his recent book The Story of Earth (Viking-Penguin) was finalist in the Royal Society and Phi Beta Kappa science book competitions. Hazen has been recipient of numerous awards, including the 2021 IMA Medal, the 2016 Roebling Medal of the Mineralogical Society of America, and the 2012 Virginia Outstanding Faculty Award. In 2020 he was elected Foreign Member of the Russian National Academy of Sciences. The biomineral “hazenite” was named in his honor. Since 2008, Hazen and his colleagues have explored “mineral evolution” and “mineral ecology”—new approaches that exploit large and growing mineral data resources to understand the co-evolution of the geosphere and biosphere. In October 2016 Hazen retired from a 40-year career as a professional trumpeter, during which he performed with numerous ensembles including the Metropolitan Opera, Royal Ballet, and National Symphony."
Alec Brenner - Abstract: Many iron oxide and sulfide minerals are ferromagnetic, including magnetite, hematite, and pyrrhotite. This means that these minerals become magnetized when they form in a magnetic field and can then retain their magnetization when the field is changed or removed. As a result, these minerals - and the rocks they occur in - can preserve records of the ambient magnetic field in deep geologic time. Paleomagnetists study these ancient magnetic signals to understand the evolution of Earth's magnetic field and the motions of tectonic plates through it, among other applications.
However, Earth's oldest preserved rocks have traditionally been considered inappropriate for paleomagnetic work. Billions of years of metamorphism, deformation, and tectonic events have erased most of their magnetic records, obscuring our view of early Earth's magnetic field and plate tectonics. This is especially true before about 3 billion years ago, coinciding with the evolution of some of the first life on Earth.
Fortuitously, my work in the lab of Prof. Roger Fu has identified volcanic rocks in Western Australia that retained 3.2-billion-year-old magnetizations. I will discuss our data from these rocks, which document the oldest described reversal of Earth's magnetic field, as well as large plate motions of the underlying of crust. Of particular interest to micromounters are our magnetic microscopy observations. Using a state-of-the-art magnetic microscope developed by Prof. Fu, we have directly mapped the magnetized signals in our rocks at micron scale (0.001 mm). By closely examining the textures and mineral populations associated with the magnetic minerals in our samples, we have established that they became magnetized when the rocks were chemically altered by hot seawater during a hydrothermal event 3.2 billion years ago. This alteration removed original magnetic minerals and grew new ones via a complex sequence of co-occurring metamorphic reactions. Raman spectroscopy, electron microscopy, traditional petrographic analyses, and in-situ geochronology further constrain the timing and thermal conditions of this alteration. Our newfound understanding of how these ancient rocks became magnetized paves the way for new studies of Earth’s earliest magnetic record.
Brenner's Biography: Alec is a fervent rockhound and native of McLean. He is also a fifth-year PhD student at Harvard University, where his research focuses on the mineralogical basis of magnetism preserved in Earth’s oldest rocks. This in turn informs his reconstructions of tectonics, core circulation, and surface processes on the early Earth. This research has thus far included field work in rocks about three billion years old in Australia, South Africa, and Minnesota.
Alec first got interested in minerals after finding prehnite from the Vulcan Manassas Quarry in the gravel of his elementary school parking lot. He continued rockhounding and fossil collecting with the Northern Virginia Mineral Club, which he joined in 2007. While attending Thomas Jefferson High School for Science and Technology (TJHSST), Alec’s interests matured into geoscience research. This included collaborations with micropaleontologists and planetary scientists at the US Geological Survey, The Smithsonian Institution, and NASA’s Goddard Space Flight Center. He attended the California Institute of Technology (Caltech) for his undergraduate studies, earning a BS in Geology in 2017. There, he found his true loves, including his now-wife Netgie and his current specializations in paleomagnetism, deep-time Earth history, and mineralogy.
Alec currently lives in Arlington, Massachusetts, where he hikes atop the rocks of the Avalonian Terrane, counts the days until he can resume field work in Australia (pictured), and dotes on his tabby cat Sienna. A special thanks to Prof. Roger Fu, Alec’s academic advisor at Harvard’s Paleomagnetics Lab, for funding and contributing his expert guidance to the work presented here. Alec also thanks his parents Sara and Paul Brenner, who tirelessly supported his odd fascinations with rocks and drove him to so many NVMC meetings and field trips as a kid.
