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Joel HurowitzAssociate Professor B.Sc., State University of New York at Albany, 1996 M.Sc., Earth and Space Sciences, Stony Brook University, 2001 Ph.D., Geosciences, Stony Brook University, 2006 Hydrogeologist, Leggette Brashears & Graham, Inc., 1996-98 Caltech Postdoctoral Scholar at Jet Propulsion Lab, 2006-2007 Research Scientist, NASA-Jet Propulsion Lab, 2007-2013 Research Scientist, Stony Brook University, 2013-2014 Faculty Member at Stony Brook since Fall 2014 |
1. In-situ Exploration of the Surface of Mars: Observations by a veritable fleet of orbiters sent to Mars have been used to develop and refine hypotheses about how the Red Planet evolved from a more Earth-like state in its early history, to the cold desert world we observe today. Testing these hypotheses requires close-up examination of the sedimentary rock record, which contains the clues needed to understand climate evolution on Mars. I am the Deputy Principal Investigator for the Planetary Instrument for X-ray Lithochemistry (PIXL), which was selected by NASA to fly on the upcoming Mars 2020 Rover mission (M2020). This project is based at the NASA-Jet Propulsion Laboratory. I am working with PIXL Principal Investigator Dr. Abigail Allwood to develop and test PIXL prototypes and the PIXL flight instrument for operation after landing on Mars, currently scheduled for the year 2021. My laboratory is outfitted with a “breadboard” version of the PIXL instrument, which is available for students to use for chemical element mapping to support their research, and to train for opportunities to get involved in PIXL instrument operations on M2020.
2. Analogue Field Studies (1): My group is exploring the chemical record of Paleoproterozoic seawater preserved in iron formation as an analogue to Fe-rich water bodies on the early surface of Mars, in collaboration with Professors Greg Henkes and Troy Rasbury. Iron formations are characterized by high Fe-abundances and a variety of Fe-minerals formed by interactions between dissolved Fe2+, atmospheric oxidants, and carbon. Terrestrial iron formations are also host to some of Earth’s most ancient records of life, including molecular biomarkers and microfossils. Accordingly, terrestrial iron formations, like the Paleoproterozoic Gunflint Formation, can provide valuable insight into Fe-redox and precipitation processes on the ancient surface of Mars. Critically, the Gunflint contains the Fe-carbonate mineral siderite, which can be exploited to gain insight into the habitability of water bodies on early Mars. Our goal is to determine the conditions that gave rise to abundant siderite in iron formation through the application of experimental (see below) research in the Fe-Mg-H-C-O system and stable and clumped isotopic data derived from samples of iron formation. We have developed petrographic criteria to understand which carbonate phases are most likely to preserve a primary to early diagenetic record of Precambrian seawater chemistry.
This work formed the basis of Ph.D. graduate Dr. Ella Holme
We will begin applying these tools to more ancient records derived from BASE core samples from the 3.2Ga Moodies Group, which we have recently been invited to work with.
Analogue Field Studies (2): On Earth, the geochemical and mineralogical composition of clastic sediments are dominated by inputs from the petrologically-evolved granodioritic upper continental crust and recycled sedimentary materials derived from this crust. A comprehensive understanding exists of the processes that influence the composition of sediments derived from felsic materials as they evolve from their source terrains, along transport pathways, to their sites of accumulation. In contrast, far fewer examples of sub-aerially exposed basaltic crust with extensively developed source-to sink sedimentary drainages exist on Earth. Outside of subaerial weathering of basalts, the processes and products of basaltic sedimentation have gone largely unstudied in the terrestrial geological record. As a result, we lack a suitable reference frame in which to place the Martian sedimentary rock record, which is dominated by first-cycle basaltic sources. We have performed work to build this reference frame through a field research program based in fluvial drainage systems in basaltic terrains, including Idaho, Iceland, and Hawaii.
This work formed the basis of Ph.D. graduate Dr. Michael Thorpe
3. Experimental Aqueous Geochemistry:Our group uses an experimental approach in which early terrestrial and Martian fluid conditions are constrained based on whether experimentally precipitated minerals (or mineral assemblages) provide a match to mineralogical and geochemical observations from the sedimentary record these two planets. These experiments provide constraints on the inorganic chemical properties of surface water bodies that may have hosted the chemical reactions that gave rise to the origin of life on Earth, work that is supported by the Simons Collaboration on the Origins of Life. We conduct mineral precipitation experiments in anaerobic chambers order to approximate volcanically-derived, anoxic atmospheric conditions on the early terrestrial and Martian surfaces. Within these experimental systems, we are currently pursuing three main themes of investigation:
- Explore the conditions and rates of Fe-oxidation by ultraviolet light under anoxic conditions, led by FINESST grant recipient Victoria Rivera-Banuchi.
- Investigate the conditions of formation of Fe-Mg carbonate minerals, led by Ph.D. candidate Madison Morris
- Investigate the importance of oxidative processes driven by oxyhalogen species on the ancient and modern surface of Mars, led by postdoctoral researcher Kaushik Mitra
4. The reactivity and toxicity of planetary regolith: Silicate minerals that have been mechanically pulverized by impact processes on planetary bodies have surfaces that are populated by broken, highly reactive, cation-oxygen bonds. These broken bonds generate reactive oxygen species (e.g., OH˙, O2˙-, and H2O2) and O2when contacted by liquid water or water vapor. The reactivity of quartz has been well studied by medical researchers and toxicologists, as it bears directly on the causes behind silicosis. However, the reactivity of mineral phases on basaltic planetary bodies such as the Moon is little studied, and requires further exploration to assess the potential toxicity of planetary regolith to astronauts. We have performed a range of experimental projects that explored this theme through the Stony Brook node of the Solar System Virtual Exploration and Research Institute (SSERVI), led by Professor Timothy Glotch.
This work formed the basis of Ph.D. graduate Dr. Donald Hendrix