Rosalind Tuthill Helz is a Scientist Emeritus at the Florence Bascom Geoscience Center.
Rosalind Helz is a Scientist Emeritus at the Frances Bascom Center. She received her undergraduate degree in Geology from Stanford University in 1965, and graduate degrees in Geochemistry and Mineralogy from Penn State University in 1968 (M.S.) and 1978 (Ph.D). Since joining the USGS in March 1968, she has devoted her career to studying the behavior of mafic magmas, specializing in the use of petrology and chemistry to elucidate differentiation processes in mafic magmatic systems. Ongoing work includes completion of reports on the long-term study of Kilauea Iki lava lake, Hawaii and completion of reports on studies of the basal sill swarm associated with the Stillwater Complex, Montana.
Professional Experience
Smithsonian Museum of Natural History (Research Associate)
Education and Certifications
Ph.D, Mineralogy and Petrology, The Pennsylvania State University, 1978
M.Sc., Mineralogy and Petrology, The Pennsylvania State University, 1968
B.S., Geology, Stanford University, 1965
Science and Products
Filter Total Items: 47
Trace-element analyses of core samples from the 1967-1988 drillings of Kilauea Iki lava lake, Hawaii
This report presents previously unpublished analyses of trace elements in drill core samples from Kilauea Iki lava lake and from the 1959 eruption that fed the lava lake. The two types of data presented were obtained by instrumental neutron-activation analysis (INAA) and energy-dispersive X-ray fluorescence analysis (EDXRF). The analyses were performed in U.S. Geological Survey (USGS) laboratories
Whole-rock analyses of core samples from the 1988 drilling of Kilauea Iki lava lake, Hawaii
This report presents and evaluates 64 major-element analyses of previously unanalyzed Kilauea Iki drill core, plus three samples from the 1959 and 1960 eruptions of Kilauea, obtained by X-ray fluorescence (XRF) analysis during the period 1992 to 1995. All earlier major-element analyses of Kilauea Iki core, obtained by classical (gravimetric) analysis, were reported and evaluated in Helz and others
Diffusion-driven magnesium and iron isotope fractionation in Hawaiian olivine
Diffusion plays an important role in Earth sciences to estimate the timescales of geological processes such as erosion, sediment burial, and magma cooling. In igneous systems, these diffusive processes are recorded in the form of crystal zoning. However, meaningful interpretation of these signatures is often hampered by the fact that they cannot be unambiguously ascribed to a single process (e.g.,
Iron isotope fractionation during magmatic differentiation in Kilauea Iki lava lake
Magmatic differentiation helps produce the chemical and petrographic diversity of terrestrial rocks. The extent to which magmatic differentiation fractionates nonradiogenic isotopes is uncertain for some elements. We report analyses of iron isotopes in basalts from Kilauea Iki lava lake, Hawaii. The iron isotopic compositions (56Fe/54Fe) of late-stagemeltveins are 0.2 permil (per thousand) greater
Processes active in mafic magma chambers: The example of Kilauea Iki Lava Lake, Hawaii
Kilauea Iki lava lake formed in 1959 as a closed chamber of 40 million m3 of picritic magma. Repeated drilling and sampling of the lake allows recognition of processes of magmatic differentiation, and places time restrictions on the periods when they operated. This paper focuses on evidence for the occurrence of lateral convection in the olivine-depleted layer, and constraints on the timing of thi
Fractionation of the platinum-group elments and Re during crystallization of basalt in Kilauea Iki Lava Lake, Hawaii
Kilauea Iki lava lake formed during the 1959 summit eruption of Kilauea Volcano, then crystallized and differentiated over a period of 35??years. It offers an opportunity to evaluate the fractionation behavior of trace elements in a uniquely well-documented basaltic system. A suite of 14 core samples recovered from 1967 to 1981 has been analyzed for 5 platinum-group elements (PGE: Ir, Os, Ru, Pt,
Reducing loss of life and property from disasters: A societal benefit area of the strategic plan for U.S. Integrated Earth Observation System (IEOS)
Natural and technological disasters, such as hurricanes and other extreme weather events, earthquakes, volcanic eruptions, landslides and debris flows, wildland and urban-interface fires, floods, oil spills, and space-weather storms, impose a significant burden on society. Throughout the United States, disasters inflict many injuries and deaths, and cost the nation $20 billion each year (SDR, 2003
Investigation of magnesium isotope fractionation during basalt differentiation: Implications for a chondritic composition of the terrestrial mantle
To investigate whether magnesium isotopes are fractionated during basalt differentiation, we have performed high-precision Mg isotopic analyses by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) on a set of well-characterized samples from Kilauea Iki lava lake, Hawaii, USA. Samples from the Kilauea Iki lava lake, produced by closed-system crystal-melt fractionation, range
Monitoring ground deformation from space
No abstract available.
Satellite imagery for volcanic hazards mitigation
The Committee on Earth Observation Satellites (CEOS) seeks to foster cooperation to increase the usefulness and accessibility of satellite imagery. In 1997, CEOS initiated the Disaster Management Support Project to assess the present and potential use of satellite-derived information for volcanic hazards mitigation. The final report of the CEOS Volcanic Hazards Working Group reviews current use of
The absence of lithium isotope fractionation during basalt differentiation: New measurements by multicollector sector ICP-MS
We report measurements of the isotopic composition of lithium in basalts using a multicollector magnetic sector plasma-source mass spectrometer (MC-ICP-MS). This is the first application of this analytical technique to Li isotope determination. External precision of multiple replicate and duplicate measurements for a variety of sample types averages ??1.1??? (2?? population). The method allows for
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Filter Total Items: 47
Trace-element analyses of core samples from the 1967-1988 drillings of Kilauea Iki lava lake, Hawaii
This report presents previously unpublished analyses of trace elements in drill core samples from Kilauea Iki lava lake and from the 1959 eruption that fed the lava lake. The two types of data presented were obtained by instrumental neutron-activation analysis (INAA) and energy-dispersive X-ray fluorescence analysis (EDXRF). The analyses were performed in U.S. Geological Survey (USGS) laboratoriesWhole-rock analyses of core samples from the 1988 drilling of Kilauea Iki lava lake, Hawaii
This report presents and evaluates 64 major-element analyses of previously unanalyzed Kilauea Iki drill core, plus three samples from the 1959 and 1960 eruptions of Kilauea, obtained by X-ray fluorescence (XRF) analysis during the period 1992 to 1995. All earlier major-element analyses of Kilauea Iki core, obtained by classical (gravimetric) analysis, were reported and evaluated in Helz and othersDiffusion-driven magnesium and iron isotope fractionation in Hawaiian olivine
Diffusion plays an important role in Earth sciences to estimate the timescales of geological processes such as erosion, sediment burial, and magma cooling. In igneous systems, these diffusive processes are recorded in the form of crystal zoning. However, meaningful interpretation of these signatures is often hampered by the fact that they cannot be unambiguously ascribed to a single process (e.g.,Iron isotope fractionation during magmatic differentiation in Kilauea Iki lava lake
Magmatic differentiation helps produce the chemical and petrographic diversity of terrestrial rocks. The extent to which magmatic differentiation fractionates nonradiogenic isotopes is uncertain for some elements. We report analyses of iron isotopes in basalts from Kilauea Iki lava lake, Hawaii. The iron isotopic compositions (56Fe/54Fe) of late-stagemeltveins are 0.2 permil (per thousand) greaterProcesses active in mafic magma chambers: The example of Kilauea Iki Lava Lake, Hawaii
Kilauea Iki lava lake formed in 1959 as a closed chamber of 40 million m3 of picritic magma. Repeated drilling and sampling of the lake allows recognition of processes of magmatic differentiation, and places time restrictions on the periods when they operated. This paper focuses on evidence for the occurrence of lateral convection in the olivine-depleted layer, and constraints on the timing of thiFractionation of the platinum-group elments and Re during crystallization of basalt in Kilauea Iki Lava Lake, Hawaii
Kilauea Iki lava lake formed during the 1959 summit eruption of Kilauea Volcano, then crystallized and differentiated over a period of 35??years. It offers an opportunity to evaluate the fractionation behavior of trace elements in a uniquely well-documented basaltic system. A suite of 14 core samples recovered from 1967 to 1981 has been analyzed for 5 platinum-group elements (PGE: Ir, Os, Ru, Pt,Reducing loss of life and property from disasters: A societal benefit area of the strategic plan for U.S. Integrated Earth Observation System (IEOS)
Natural and technological disasters, such as hurricanes and other extreme weather events, earthquakes, volcanic eruptions, landslides and debris flows, wildland and urban-interface fires, floods, oil spills, and space-weather storms, impose a significant burden on society. Throughout the United States, disasters inflict many injuries and deaths, and cost the nation $20 billion each year (SDR, 2003Investigation of magnesium isotope fractionation during basalt differentiation: Implications for a chondritic composition of the terrestrial mantle
To investigate whether magnesium isotopes are fractionated during basalt differentiation, we have performed high-precision Mg isotopic analyses by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) on a set of well-characterized samples from Kilauea Iki lava lake, Hawaii, USA. Samples from the Kilauea Iki lava lake, produced by closed-system crystal-melt fractionation, rangeMonitoring ground deformation from space
No abstract available.Satellite imagery for volcanic hazards mitigation
The Committee on Earth Observation Satellites (CEOS) seeks to foster cooperation to increase the usefulness and accessibility of satellite imagery. In 1997, CEOS initiated the Disaster Management Support Project to assess the present and potential use of satellite-derived information for volcanic hazards mitigation. The final report of the CEOS Volcanic Hazards Working Group reviews current use ofThe absence of lithium isotope fractionation during basalt differentiation: New measurements by multicollector sector ICP-MS
We report measurements of the isotopic composition of lithium in basalts using a multicollector magnetic sector plasma-source mass spectrometer (MC-ICP-MS). This is the first application of this analytical technique to Li isotope determination. External precision of multiple replicate and duplicate measurements for a variety of sample types averages ??1.1??? (2?? population). The method allows for