A5032968489- Astro and Planetary Science
- Planetary Science and Exploration
- Geological and Geochemical Analysis
- Crystal Structures and Properties
- Isotope Analysis in Ecology
- High-pressure geophysics and materials
- Mineralogy and Gemology Studies
- Paleontology and Stratigraphy of Fossils
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Geochemistry and Geologic Mapping
- X-ray Diffraction in Crystallography
- Methane Hydrates and Related Phenomena
- Geochemistry and Elemental Analysis
- Nuclear Physics and Applications
- Geological formations and processes
- Chemical Synthesis and Characterization
- Glass properties and applications
- Advanced Condensed Matter Physics
- earthquake and tectonic studies
- Geological Modeling and Analysis
- Nuclear materials and radiation effects
- Space Science and Extraterrestrial Life
- Spacecraft and Cryogenic Technologies
- Metal Extraction and Bioleaching
Royal Ontario Museum
2016-2025
University of Toronto
2013-2025
University of Manitoba
2003-2021
Royal Ottawa Mental Health Centre
2016-2018
University College London
2010
Los Alamos National Laboratory
2004-2007
University of Arizona
2004
Cornell University
2004
University of Dundee
1999
Encapsulating Earth's deep water filter Small inclusions in diamonds brought up from the mantle provide valuable clues to mineralogy and chemistry of parts Earth that we cannot otherwise sample. Tschauner et al. found high-pressure form called ice-VII sourced between 410 660 km depth, part known as transition zone. The zone is a region where stable minerals have high storage capacity. suggest local aqueous pockets at boundary owing release chemically bound rock cycles out this region....
Abstract Evaporation or freezing of water-rich fluids with dilute concentrations dissolved salts can produce brines, as observed in closed basins on Earth 1 and detected by remote sensing icy bodies the outer Solar System 2,3 . The mineralogical evolution these brines is well understood regard to terrestrial environments 4 , but poorly constrained for extraterrestrial systems owing a lack direct sampling. Here we report occurrence salt minerals samples asteroid (101955) Bennu returned...
A quenchable superhard high-pressure carbon phase was synthesized by cold compression of nanotubes. Carbon nanotubes were placed in a diamond anvil cell, and x-ray diffraction measurements conducted to pressures ≈100 GPa. hexagonal formed at ≈75 GPa preserved room conditions. X-ray transmission electron microscopy diffraction, as well Raman spectroscopy ambient conditions, explicitly indicate that this is sp 3 -rich polymorph, rather than diamond. The cell parameters refined 0 = 2.496(4) Å,...
Abstract Just as geological samples from Earth record the natural history of our planet, astromaterials hold solar system and beyond. Astromaterials acquisition curation practices have direct consequences on contamination levels hence types questions that can be answered about degree precision expected those answers. Advanced was developed a cross-disciplinary field to improve in existing collections for future sample return activities, including meteorite cosmic dust are collected Earth....
Direct analysis of the composition Mars is possible through delivery meteorites to Earth. Martian include ∼165 2400 Ma shergottites, originating from depleted enriched mantle sources, and ∼1340 nakhlites chassignites, formed by low degree partial melting a source. To date, no unified model has been proposed explain petrogenesis these distinct rock types, despite their importance for understanding formation evolution Mars. Here we report coherent geochemical dataset chassignites revealing...
The Mars Sample Return (MSR) Campaign must meet a series of scientific and technical achievements to be successful. While the respective engineering responsibilities retrieve samples have been formalized through Memorandum Understanding between ESA NASA, roles elements yet fully defined. In April 2020, NASA jointly chartered MSR Science Planning Group 2 (MSPG2) build upon previous planning efforts in defining 1) an end-to-end Program 2) needed functionalities design requirements for...
Abstract The matrix of the C2‐ungrouped Tarda meteorite contains abundant smectite minerals that swell and crumble when exposed to polar liquids, causing sample rapidly slake. This phenomenon presents a serious challenge polishing meteorite, as common liquids used on carbonaceous chondrites, such water, ethanol, ethylene glycol, isopropyl alcohol, are will cause swell, making it unsuitable for some analyses. Hexane mineral oil nonpolar were found not induce swelling highly expansive...
Abstract The OSIRIS‐REx mission returned a sample of regolith from the carbonaceous asteroid Bennu in September 2023. We present preliminary situ investigations petrology and petrography selected particles ranging size 0.5 to 3 mm. Using combination optical electron beam techniques, we investigate whole specimens polished sections belonging morphologically visually distinct categories particles. find that morphological differences are reflective petrographic petrologic differences, leading...
The crystal structures of three nepheline samples, (1) K 1.91 Na 6.04 Si 8.15 Al 7.72 Fe 3+ 0.10 O 32 , a 9.9995(6), c 8.384(2) Å, P6 3 Z = 1, D x 2.673 g cm -3 from the Khibina-Lovozero complex, Kola Peninsula, Russia, (2) 1.60 6.21 Ca 0.08 8.44 7.43 9.985(1), 8.372(1) 2.660 g/cm Bancroft, Ontario, Canada, and (3) 1.76 5.86 0.13 8.12 7.84 0.04 9.9979(6), 8.3852(2), 2.654 Monte Somma, Italy, have been refined to R 1 indices 1.8, 2.7 1.7% using 1273, 1191 1364 unique observed (| F o | > 4F)...
Abstract The Mars 2020/Mars Sample Return (MSR) Depot Science Community Workshop was held on September 28 and 30, 2022, to assess the Scientifically‐Return Worthy (SRW) value of full collection samples acquired by rover Perseverance at Jezero Crater, a proposed subset be left as First location within Crater called Three Forks. primary outcome workshop that community is in consensus following statement: set ten sample tubes includes seven rock samples, one regolith sample, atmospheric witness...
The Mars Sample Return (MSR) Campaign represents one of the most ambitious scientific endeavors ever undertaken. Analyses martian samples would offer unique science benefits that cannot be attained through orbital or landed missions rely only on remote sensing and
Kinetic studies are reported of the effect methanol on rate formation CO2- and CH4-hydrates by means in situ time-of-flight neutron powder diffraction. The experiments were carried out at temperatures ranging from 200 to 250 K pressures up 7 MPa. samples prepared mixtures ground, deuterated ice (up 20 vol%), which transformed into or pressurizing systems with corresponding gas. observed rates hydrates orders magnitude higher than pure under same pressure temperature conditions. Glycols...
Abstract Terrestrial weathering of hot desert achondrite meteorite finds and heterogeneous phase distributions in meteorites can complicate interpretation petrological geochemical information regarding parent‐body processes. For example, understanding the effects is important for establishing chalcophile siderophile element within sulfide metal phases meteorites. Heterogeneous mineral distribution relatively coarsely grained also lead to uncertainties relating compositional...
The elemental and chlorine isotope compositions of calcium-phosphate minerals are key recorders the volatile inventory Mars, as well planet's endogenous magmatic hydrothermal history. Most martian meteorites have clear evidence for exogenous impact-generated deformation metamorphism, yet effects these shock metamorphic processes on isotopic records contained within calcium phosphates not been evaluated. Here we test a single cycle systematics in apatite from highly shocked, enriched...
Abstract. Baddeleyite is a powerful chronometer of mafic magmatic and meteorite impact processes. Precise accurate U–Pb ages can be determined from single grains by isotope dilution thermal ionization mass spectrometry (ID-TIMS), but this requires disaggregation the host rock for grain isolation dissolution. As result, technique rarely applied to precious samples with limited availability (such as lunar, Martian, asteroidal meteorites returned samples) or containing small baddeleyite that...
Abstract Impact cratering on the Moon and derived size-frequency distribution functions of lunar impact craters are used to determine ages unsampled planetary surfaces across Solar System. Radiometric dating samples provides an absolute age baseline, however, crater-chronology for remain poorly constrained beyond 3.9 billion years. Here we present U–Pb geochronology phosphate minerals within shocked norites a boulder from Apollo 17 Station 8. These record older event around 4.2 years ago,...
In situ neutron inelastic scattering experiments on hydrogen adsorbed into a fully deutrated tetrahydrofuran-water ice clathrate show that the has three rotational excitations (transitions between J=0 and 1 states) at approximately 14meV in both energy gain loss. These transitions could be unequivocally assigned since there was residual orthohydrogen low temperatures (slow conversion to ground state) resulting an observable J=1→0 transition 5K (kT=0.48meV). A doublet loss 28.5meV is...