Jessica Barnes

NASA Johnson Space Center · ARES

Enstatite‐rich meteorites, including the aubrites, formed under conditions of very low oxygen fugacity (ƒO2: iron‐wüstite buffer −2 to −6) and thus offer the ability to study reduced magmatism present on multiple bodies in our solar system. Elemental partitioning among metals, sulfides, and silicates is poorly constrained at low ƒO2; however, studi...

Halogens are mobile in geological fluids, making them excellent tracers of volatile activity. Halogen-bearing minerals in diverse planetary materials, coupled with chlorine isotope compositions of bulk samples and minerals, can be used to infer the presence of fluids on planetary surfaces, crusts, and interiors. Halogen element and isotopic evidenc...

We conducted a petrologic study of apatite within eight unbrecciated, non-cumulate eucrites and two monomict, non-cumulate eucrites. These data were combined with previously published data to quantify the abundances of F, Cl, and H2O in the bulk silicate portion of asteroid 4 Vesta (BSV). Using a combination of apatite-based melt hygrometry/chlorom...

We conducted in situ Cl isotopic measurements of apatite within intercumulus regions and within a holocrystalline olivine-hosted melt inclusion in magnesian-suite troctolite 76535 from Apollo 17. These data were collected to place constraints on the Cl-isotopic composition of the last liquid to crystallize from the lunar magma ocean (i.e., urKREEP,...

The abundance and distribution of water within Mars through time plays a fundamental role in constraining its geological evolution and habitability. The isotopic composition of Martian hydrogen provides insights into the interplay between different water reservoirs on Mars. However, D/H (deuterium/hydrogen) ratios of Martian rocks and of the Martia...

The presence of H2O within differentiated terrestrial bodies in the inner Solar System is well established; however, the source(s) of this H2O and the time of its arrival to the inner Solar System is an area of active study. At present, the prevailing model for the origin of inner Solar System H2O calls upon carbonaceous chondrites as the source. T...

Generally, terrestrial rocks, martian and chondritic meteorites exhibit a relatively narrow range in bulk and apatite Cl isotope compositions, with δ³⁷Cl (per mil deviation from standard mean ocean chloride) values between −5.6 and +3.8‰. Lunar rocks, however, have more variable bulk and apatite δ³⁷Cl values, ranging from ∼−4 to +40‰. As the Howard...

The isotopes of chlorine (³⁷Cl and ³⁵Cl) are highly fractionated in lunar samples compared to most other Solar System materials. Recently, the chlorine isotope signatures of lunar rocks have been attributed to large-scale degassing processes that occurred during the existence of a magma ocean. In this study we investigated how well a suite of lunar...

The relative abundances of chlorine isotopes measured in low-Ti basalts from the Moon appear to reflect mixing between two reservoirs: One component representing the urKREEP—the final product of the crystallization of the lunar magma ocean—with δ37Cl=+25‰ (relative to Standard Mean Ocean Chlorine), the other representing either a mare basalt reserv...

Coordinated Microanalysis of Phosphates in High-Titanium Lunar Basalts - Volume 24 Supplement - J. J. Barnes, M. S. Thompson, F. M. McCubbin, J. Y. Howe, Z. Rahman, S. Messenger, T. Zega

Compared to most other planetary materials in the Solar System, some lunar rocks display high δ³⁷Cl signatures. Loss of Cl in a H Cl environment has been invoked to explain the heavy signatures observed in lunar samples, either during volcanic eruptions onto the lunar surface or during large scale degassing of the lunar magma ocean. To explore the...

Despite more than 40 years of studying Apollo samples, the age and early evolution of the Moon remain contentious. Following the formation of the Moon in the aftermath of a giant impact, the resulting Lunar Magma Ocean (LMO) is predicted to have generated major geochemically distinct silicate reservoirs, including the sources of lunar basalts. Samp...

Introduction: In general, Solar System materials exhibit a relatively narrow range in bulk Cl isotope compositions , with terrestrial rocks and martian and chondritic meteorites having δ 37 C values of ~-4 to ~ +1.8 ‰ [1-3]. However, lunar rocks are an important exception, displaying a significant range in their bulk and apatite δ 37 Cl values from...

Current models for the Moon's formation have yet to fully account for the thermal evolution of the Moon in the presence of H2O and other volatiles. Of particular importance is chlorine, since most lunar samples are characterised by unique heavy δ37Cl values, significantly deviating from those of other planetary materials, including Earth, for which...

div class="title">Investigating the History of Magmatic Volatiles in the Moon Using NanoSIMS - Volume 22 Issue S3 - Jessica J. Barnes, Mahesh Anand, Ian A. Franchi

The Apollo-derived tenet of an anhydrous Moon has been contested following measurement of water in several lunar samples that require water to be present in the lunar interior. However, significant uncertainties exist regarding the flux, sources and timing of water delivery to the Moon. Here we address those fundamental issues by constraining the m...

Volatile elements play a key role in the dynamics of planetary evolution. Extensive work has been carried out to determine the abundance, distribution, and source(s) of volatiles in planetary bodies such as the Earth, Moon, and Mars. A recent study showed that the water in apatite from eucrites has similar hydrogen isotopic compositions compared to...

We have measured the abundance and isotopic composition of water in apatites from several lunar rocks representing Potassium (K), Rare Earth Elements (REE), and Phosphorus (P) - KREEP - rich lithologies, including felsites, quartz monzodiorites (QMDs), a troctolite, and alkali anorthosite. The H-isotope data from apatite provide evidence for multip...

Many studies exist on magmatic volatiles (H, C, N, F, S, Cl) in and on the Moon, within the last several years, that have cast into question the post-Apollo view of lunar formation, the distribution and sources of volatiles in the Earth-Moon system, and the thermal and magmatic evolution of the Moon. However, these recent observations are not the f...

Introduction: Recently, there have been numerous studies investigating the amount and isotopic composi-tion of water in lunar materials [e.g., 1-8]. The com-bined results from these investigations have provided two major insights that have challenged the long-standing paradigm of an anhydrous Moon. The first major insight relates to the new estimat...

A paradigm shift has recently occurred in our knowledge and understanding of water in the lunar interior. This has transpired principally through continued analysis of returned lunar samples using modern analytical instrumentation. While these recent studies have undoubtedly measured indigenous water in lunar samples they have also highlighted our...

We have characterized the petrology and mineral chemistry of mesostasis areas in four Apollo mare basalts (10044, 12064, 15058, and 70035).

The recent discoveries of hydrogen (H) bearing species on the lunar surface and in samples derived from the lunar interior have necessitated a paradigm shift in our understanding of the water inventory of the Moon, which was previously considered to be a ‘bone-dry’ planetary body. Most sample-based studies have focused on assessing the water conten...

We present the first apatite water content and H-isotope results from an apatite-rich ferroan anorthosite-like lithology from meteorite Allan Hills A81005.

We report new measurements of water content and corresponding hydrogen-isotopic composition for apatite in the rare KREEP and high-Al mare basalts.

We present new data providing evidence for a low-deuterium reservoir in the lunar interior with some of the lowest D/H values yet reported in lunar apatite.

We have measured the OH content and H-isotopic composition of apatite grains from two Apollo lunar impact-melt breccias (15405 and 65785).

Mesostasis modal abundances in mare basalts are presented, combined with MELTS and SPICEs modeling to constrain melt compositions in which apatite forms.

In this study we have measured the OH contents and D/H ratios in apatite grains in lunar basalts. These new data considerably expand the limited dataset published so far. The data presented in this study also show that there is a major difference between high- and low-Ti mare basalts in terms of their OH and D/H systematics. Apatites in high-Ti bas...

The lunar interior is now believed to be much wetter than was envisaged during the Apollo era [e.g. 1]. We have investigated the OH content and H isotopic composition of apatite grains in two lunar magnesian (Mg) suite rocks and demonstrate that the primitive lunar magma ocean (LMO) cumulates contained up to 6 ppm H2O. We also show that the primiti...

We explore how the A33 moonquake nest can be used as an anchor for a geophysical network that can be used to explore the interior structure of the Moon.

Survey of possible landing sites/geophysical array configurations for addressing Concept 2 of the NRC report "The Scientific Context for Exploration of the Moon."

We report the OH contents and the H-isotopic composition of apatites from three basaltic lunar meteorites to constrain the volatile inventory of the lunar interior.

Our new data on the OH content and D/H ratio in apatites from low- and high-Ti Apollo mare basalts indicate involvement of distinct petrogenetic processes.

Sample return landing sites that provide information regarding the composition, structure, and evolution of the lunar interior are identified.

This paper describes the development of a technique using NanoSIMS to make precise and accurate determination of the hydrogen isotopic composition and the hydroxyl content of apatite grains. An experiment was also performed to determine the effects, if any, of using secondary electron microscopy (SEM) and electron probe micro-analysis (EPMA) on the...

Apatites in low-Ti mare basalts from the Apollo 15 landing site display a large range of OH content from about 100 ppm up to ~ 2000 ppm. The D/H ratios measured in these apatites yielded D values of ~ 550-1050 ‰. On the other hand, apatites in the KREEP basalt 15386 have less than 250 ppm OH and yielded D values in the range ~ 20-500 ‰. These dat...

We report δD values and hydroxyl contents of apatite grains from Apollo mare basalt 12064 and lunar mare basalt meteorite Miller Range MIL 05035.