Search NASA⌕ Search

SEARCH · Search NASA

Results for “magmatic”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Spatial Distribution of Volcanic Hotspots and Paterae on Io: Implications for Tidal Heating Models and Magmatic Pathways

Io, the innermost of Jupiter's Galilean satellites, is the most volcanically active body in the Solar. System. Io's global mean heat flow is approximately 2 W/square m, which is approximately 20 times larger than on Earth. High surface temperatures concentrate within "hotspots" and, to date, 172 Ionian hotspots have been identified by spacecraft and Earth-based telescopes. The Laplace resonance between Io, Europa, and Ganymede maintains these satellites in noncircular orbits and causes displacement of their tidal bulges as the overhead position of Jupiter changes for each moon. Gravitational interactions between Jupiter and Io dominate the orbital evolution of the Laplacian system and generate enormous heat within to as tidal energy is dissipated. If this energy were transferred out of Io at the same rate as it is generated, then the associated surface heat flux would be 2.24 +/- 0.45 W/square m. This estimate is in good agreement with observed global heat flow, but to better constrain tidal dissipation mechanisms and infer how thermal energy is transferred to Io's surface, it is critical to closely examine the spatial distribution of volcanic features. End-member tidal dissipation models either consider that heating occurs completely in the mantle, or completely in the asthenosphere. Mixed models typically favor one-third mantle and two-thirds asthenosphere heating. Recent models also consider the effects of mantle-asthenosphere boundary permeability and asthenospheric instabilities. Deep-mantle heating models predict maximum surface heat flux near the poles, whereas asthenosphere heating models predict maxima near the equator-particularly in the Sub-Jovian and Anti-Jovian hemispheres, with smaller maxima occurring at orbit tangent longitudes. Previous studies have examined the global distribution of Ionian hotspots and patera (i.e., irregular or complex craters with scalloped edges that are generally interpreted to be volcanic calderas), but in this study, we combine a new geospatial analysis technique with an improved hotspot and paterae database .

Hamilton, C. W.↗
NASA NTRS2013

Compositions of Magmatic and Impact Melt Sulfides in Tissint And EETA79001: Precursors of Immiscible Sulfide Melt Blebs in Shergottite Impact Melts

Immiscible sulfide melt spherules are locally very abundant in shergottite impact melts. These melts can also contain samples of Martian atmospheric gases [1], and cosmogenic nuclides [2] that are present in impact melt, but not in the host shergottite, indicating some components in the melt resided at the Martian surface. These observations show that some regolith components are, at least locally, present in the impact melts. This view also suggests that one source of the over-abundant sulfur in these impact melts could be sulfates that are major constituents of Martian regolith, and that the sulfates were reduced during shock heating to sulfide. An alternative view is that sulfide spherules in impact melts are produced solely by melting the crystalline sulfide minerals (dominantly pyrrhotite, Fe(1-x)S) that are present in shergottites [3]. In this abstract we report new analyses of the compositions of sulfide immiscible melt spherules and pyrrhotite in the shergottites Tissint, and EETA79001,507, and we use these data to investigate the possible origins of the immiscible sulfide melt spherules. In particular, we use the metal/S ratios determined in these blebs as potential diagnostic criteria for tracking the source material from which the numerous sulfide blebs were generated by shock in these melts.

Ross, D. K.↗
NASA NTRS2020

Tin Abundances Require that Chassignites Originated from Multiple Magmatic Bodies Distinct from Nakhlites

Meteorites from Mars lack field context but chemical and chronologic studies have revealed remarkable links between nakhlites and chassignites. A widely held consensus is that nakhlites and chassignites originated from a large, single differentiated flow or shallow intrusive [1-5]. An Ar-Ar study assumed multiple flows based on resolvable age differences between meteorites [6], but did not address the possibility of differential cooling in a large, shallowly emplaced intrusion [1]. REE abundances in pyroxenes from nakhlites and Chassigny led [7] to argue for derivation of these rocks from distinct magmas. Volatile abundances (F, Cl, OH) in chlorapatites indicated that the entire suite of nakhlites and chassignites experienced hydrothermal interaction with a single fluid supporting a single body origin [4]. The discovery of a new chassignite, NWA 8694, extended the Mg# range from 80-54, providing a closer link to nakhlites but revealed the petrological difficulty of fractionating a single body of liquid to yield a series of olivine cumulates with such a large Mg# range [8]. When mafic magmas are emplaced into the crust, crustal assimilation can impart distinct elemental signatures if the country rock has experienced sedimentary or hydrothermal processing [9]. In this work, we used Sn abundances of nakhlites and chassignites to show that these rocks were crystallized from distinct magma batches, providing vital contextual clues to their origin.

Humayun, M.↗
NASA NTRS2024

Understanding Mercury’s Magmatic History: Geochemical Affinity, Compatibility, & Volatility Changes Due to Reduction

Mercury’s depletion in O and abundance of S substituting in as S2- has fundamental effects on the physicochemical properties of minerals and melts because O2- is the dominant rock-forming anion. These changes exert a first order effect on planetary body evolution, including the initial distribution of elements, crystallization paths, stability of phases, and mineral chemistry. Experimental and empirical data have revealed that most nominally lithophile elements become more chalcophile and/or siderophile at reducing conditions, which can be visualized through a re-interpreted Goldschmidt classification table prepared for McCubbin & Anzures’s Treatises of Geochemistry 3rd edition chapter under review. Additionally, the S bonding environment influences Mercurian phase equilibria by decreasing the stability of forsterite and anorthite while increasing the stability of enstatite, silica, and albite through re-projection of silicate ternaries.

Brendan Anthony Anzures↗
NASA NTRS2025

Diverse and Highly Differentiated Lava Suite in Jezero Crater, Mars: Constraints on Intracrustal Magmatism Revealed By Mars 2020 PIXL

The Jezero crater floor features a suite of related, iron-rich lavas that were examined and sampled by the Mars 2020 rover Perseverance , and whose textures, minerals, and compositions were characterized by the Planetary Instrument for X-ray Lithochemistry (PIXL). This suite, known as the Máaz formation (fm), includes dark-toned basaltic/trachy-basaltic rocks with intergrown pyroxene, plagioclase feldspar, and altered olivine and overlying trachy-andesitic lava with reversely zoned plagioclase phenocrysts in a K-rich groundmass. Feldspar thermal disequilibrium textures indicate that they were carried from their crustal staging area. Bulk and mafic minerals have very high FeO and low MgO to FeO total ratios, which are partially reproduced by thermodynamic models involving high-degree fractional crystallization of a gabbroic assemblage and possibly also assimilation of iron-rich basement. Together, these in situ constraints on petrogenesis provide a uniquely detailed record of intracrustal processes beneath Jezero crater during a time period not represented by Mars samples to date.

Jezero Crater floor↗
NASA NTRS1986

New insights into typical Archaean structures in greenstone terranes of western Ontario

Ongoing detailed field work in selected granitoid complexes of the western Wabigoon and Wawa Subprovinces, southern Canadian Shield, has led to several new conclusions: (1) Prominent gneiss domes are composed of prestrained tonalite-granodiorite and represent dense hoods of magmatic granitoid diapirs; (2) the deformation history of the prestrained gneiss remains to be unraveled; (3) the gneiss lacked a thick cover of mafic metavolcanics or other dense rocks at the time of magmatic diaprisim; (4) the synclinoral structure of large greenstone belts is older than the late gneiss domes and may have been initiated by volcano-tectonic processes; (5) small greenstone masses within the gneiss are complexly deformed, together with the gneiss; and, (6) no compelling evidence has been found of ductile early thrusting in the gneiss terranes. Zones of greenstone enclaves occur in hornblende-rich contaminated tonalite and are apt to be deformed magmatic septa. Elsewhere, the tonalite gneiss is biotite-rich and hornblende-poor. These conclusions rest on several new pieces of structural evidence; (1) oval plutons of syenite-diorite have magmatic strain fabrics and sharp contacts that are parallel to an axial-plane foliation in the surrounding refolded gneiss; (2) gneiss domes are lithologically composite and contain large sheath-like structures which are deformed early plutons, distorted earlier gneiss domes, or early ductile nappes produced by folding of planar plutonic septa, and (3) the predomal attitudes of gneissosity varied from point to point.

Schwerdtner, W. M.↗
NASA NTRSDate not supplied

Microstructural Characterization of Felsite Fragments From the Apollo Next Generation Sample Analysis (ANGSA) Double Drive Tube 73001/73002

While the Moon’s surface is dominated by mafic igneous products formed through the crystallization of the lunar magma ocean, and the subsequent eruption of mare basalts – felsic magmatic fragments (variably referred to as felsites, granites, rhyolites or granophyres) have been identified from a number of Apollo samples (e.g. 12013[1], 14321[2], 15405[3] and 73215[4]). Magmatic edifices like the Gruithuisen Domes – silicic constructs sometimes found proximal to the basaltic mare provinces filling nearside basins, may represent a petrogenetic origin. However, this is, is complicated by the fact that they apparently predate mare volcanism (e.g. [5]). Additionally, crater-counting indicates that these silicic surface features also postdate radiogenic ages of Apollo felsites [6]. Various modes of felsic magmatism have been invoked to explain the presence of felsic lithologies on the Moon, including: 1) fractional crystallization and silicate liquid immiscibility; 2) partial melting of lunar crust through basaltic underplating; and 3) fractional crystallization of the mare parent magmas. Although these models are plausible, based on known Apollo samples and lunar meteorites, they are complicated by the lack of sample lithologies with intermediate composition between basaltic magmas and the felsic components, and the fact that partial melting of many crustal rock types on the Moon (e.g., anorthosite, troctolites) are unlikely to form granites. Along with other unique magmatic lithologies, new felsites have been identified within the < 1 mm size fractions of the ANGSA double drive core tube (73001/73002) from Apollo 17 station 3, sampling the light mantle landslide deposit from the South Massif [7]. These additional examples of lunar felsite will help us to better constrain the processes that lead to the formation of these evolved lithologies. To do this, we have employed a gambit of high-resolution scanning electron microscopy (SEM) and scanning transmission electron microscopy (TEM) analytical techniques, including electron backscatter diffraction (EBSD), cathodoluminescence and high-angle annular dark field (HAADF) imaging. These data provide unique insights into the felsite mineralogy and microstructures including the coexistence of quartz and tridymite in many of the fragments. In addition, these analyses provide petrological context and assist targeted in situ secondary ion mass spectrometry (SIMS) measurements of the U-Pb systematics of accessory minerals, and the volatile abundances and D/H ratios of apatite grains identified within the clasts.

lunar↗