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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.

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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Chemical evidence for the genesis of the ureilites, the achondrite Chassigny and the nakhlites

An investigation has been conducted of the ureilites and the achondrite Chassigny to elucidate differences in their petrogenesis. The experimental studies reported include the determination of elemental abundances by instrumental neutron activation analysis. Attention is given to lithophile elements in ureilites, lithophile elements in Chassigny, the relationship between Chassigny and the nakhlites, and siderophile trace elements in the ureilites.

Boynton, W. V.↗
NASA NTRS1976

Thermal alteration of young kerogen in relation to petroleum genesis

Kerogen, humic acid, and lipid material were separated from a young marine sediment and heated in sealed tubes in a nitrogen atmosphere at 150 and 410 C. Gaseous and liquid products generated during heating, and also the residual organic material, were characterized by gas-liquid chromatography, elemental analysis, infrared and electron spin resonance spectroscopy, and X-ray diffraction.

Ishiwatari, R.↗
NASA NTRS1976

Mare basalt genesis - A cumulate-remelting model

In the framework of the cumulative-remelting model of lunar evolution, high-Ti basalts can be produced by extensive melting of a late-stage cumulate consisting of ilmenite-plagioclase-clinopyroxene-olivine at shallow depths immediately beneath about 60 km thick plagioclase-rich crust. Low-Ti mare basalts can be derived by small degrees of partial melting of an earlier cumulate containing mainly olivine-clinopyroxene-orthopyroxene with minor plagioclase or spinel at greater depth.

Shih, C.-Y.↗
NASA NTRS1976

History and genesis of lunar troctolite 76535 or: How old is old

The history of lunar troctolite 76535 was investigated on the basis of information from the Sm-147-Nd-143 mineral isochron age, the Nd-143 evolution, extinct Pu-224, the Kr-81-Kr exposure age and the cosmic ray exposure record. It was found that the troctolite minerals last equilibrated 4.26 plus or minus 0.06 AE ago and that the Sm-Nd system became closed at this time. The rock remained at temperatures where the loss of radiogenic Ar-40 was small.

Lugmair, G. W.↗
NASA NTRS1977

Thermal alteration experiments on organic matter from recent marine sediments in relation to petroleum genesis

Three fractions of organic matter: lipid (benzene:methanol-extractable), humic acid (alkali-extractable) and kerogen (residue) were extracted from a young marine sediment (Tanner Basin, offshore southern California) and heated for different times (5-116 hr) and temperatures (150-410 C). The volatile (gases) and liquid products, as well as residual material, were then analyzed. On a weight basis, the lipid fraction produced 58% of the total identified n-alkanes, the kerogen fraction 41%, and the humic acid less than 1%. The volatiles produced by heating the lipid and humic acid fractions were largely CO2 and water, whereas those produced from heated kerogen also included methane, hydrogen gas and small amounts of C2-C4 hydrocarbons. A mechanism for hydrocarbon production due to the thermal alteration of organic constituents of marine sediment is discussed.

Ishiwatari, R.↗
NASA NTRS1977

Genesis of howardites, diogenites, and eucrites

The reported investigation was mainly concerned with the precise determinations of major-, minor-, and trace-element abundances, especially the REE abundances in the bulk howardites in order to establish the bulk rock composition for the future chemical-mineralogical, petrographic studies of different rock types on the chemically unique howardites and diogenites if they exist. From the chemical data for the major-element abundances and the REE patterns of the howardites analyzed, it is evident that these howardites are predominantly composed of eucritic and diogenitic components. The analytical results for howardites and diogenites are shown in two tables together with the results for CRB-1. The chondritic normalized K, Sr, Ba, REE, Hf, and Sc abundances of these howardites are plotted in two graphs.

Fukuoka, T.↗
NASA NTRS1978

Zr and Nb partition coefficients - Implications for the genesis of mare basalts, KREEP, and sea floor basalts

The distribution coefficients of Zr and Nb have been found between armalcolite, ilmenite, clinopyroxene, rutile, plagioclase, and a coexisting high-Ti mare basalt melt in the 1105-1128 C temperature range. Henry's Law is not broken over the compositional range evaluated. The distribution coefficients of clinopyroxene are strongly dependent on melt and crystal compositions. The Al2O3 activity in the melt is a strong controlling parameter. It is concluded that: (1) Apollo 11 (low K) and Apollo 17 high-Ti mare basalts may have been generated by the partial melting of an ilmenite-rich cumulate, (2) Apollo 11 (high K) basalts may have been generated by a small amount of partial melting of a more fractionated ilmenite-rich cumulate, (3) KREEP magmas may have been formed as residual melts produced by fractional crystallization of the lunar magma ocean, and (4) anomalous (type II) MOR basalts may have been generated by small degrees of partial melting of a relatively undepleted mantle with clinopyroxene remaining in the residium.

Mccallum, I. S.↗
NASA NTRS1975

Magma genesis by in situ melting within the lunar crust

Blue-gray breccia 73217 represents a brecciated and partially melted assemblage of plutonic rock fragments. The textural and chemical evidence leads to the conclusion that the melt was generated within the lunar crust and that subsequent cooling and crystallization occurred prior to the transportation of this rock to the surface. The melt generated in this fashion, by in situ melting at depth, of moderately Mg-rich rocks, produced a liquid enriched in Fe, Ti, K, and P which could produce sodic ferrogabbro and granitic rocks similar to the light portion of 12013, but not KREEP.

Crawford, M. L.↗
NASA NTRS1979

Genesis of the cumulate eucrites Serra de Mage and Moore County - A geochemical study

An instrumental neutron activation analysis of element abundances in whole rock and plagioclase separates of the Serra de Mage chondrite has been conducted; plagioclase data and plagioclase mineral/liquid partition coefficients are employed to determine the REE abundances in the derivative equilibrium magmas from which Serra de Mage and Moore County chondrite plagioclases crystallized. No simple genetic relationship between the two chondrites appears likely through the route of fractional crystallization. A difference in degrees of partial melting of a similar source material (different from the source proposed for noncumulate eucrites) could be invoked to relate the two chondrites.

Ma, M.-S.↗
NASA NTRS1978

Genesis of Apollo 15 olivine normative mare basalts - Trace element correlations

Chemical and petrographic studies of 21 Apollo 15 rake basalts are reported; one pyroxene-phyric basalt, four olivine-phyric basalts, 15 olivine microgabbros, and one brecciated basalt are distinguished. The olivine-normative basalts (i.e., all samples but the pyroxene-phyric basalt) show correlation trends of La/Sm vs. La and Sm/Eu vs. La that are within the observed dispersion ranges of La/Sm and Sm/Eu ratios for a single lava flow. Trace element fractionation trends in the sample could be due to mobilization (perhaps by filter pressing) of fractionated residual liquid during the crystallization of a lava flow. However, it is also possible that the suite of olivine-normative basalts represents several basalt flows produced by partial melting of cumulate layers having interstitial liquids with variable trace-element compositions.

Ma, M.-S.↗
NASA NTRS1979

Consortium breccia 73255 - Genesis and history of two coarse-grained 'norite' clasts

A study of two clasts of coarse-grained anorthositic-noritic-troctolitic-suite norites from the fragment-laden melt rock 73255 is presented. Both clasts are igneous rocks crystallized from melts that were probably internally generated; clast 27,80 is a cumulate, and the parent magmas of both rocks probably crystallized below the lunar surface. Despite similar history, the parent rocks of the two clasts appear to be derived from distinct magma types: the 27,80 is characterized by plagioclase and orthopyroxene as the major constituents and by a high K, Nb, and Zr content, while the 27,45 type also contains augite and has a low content of K, Nb, and Zr.

James, O. B.↗
NASA NTRS1980

Genesis of breath sounds-Preliminary verification of theory

Experimental results are presented which tend to validate a previously developed theory of sound production in the human lung over a particular Reynolds number range. In addition, a new, presently nonunderstood, phenomenon was observed at higher Reynolds number. These results, which show how sound generation in the lung depends upon the physiologically important variables of volume flow rate and bronchial diameter, have potentially important application in noninvasive lung examination and the diagnosis of lung disease.

Patterson, J. L.↗
NASA NTRS1980

Genesis of the Smartville arc-ophiolite, Sierra Nevada foothills, California

Rare earth element analyses of metavolcanic rocks from the Smartville, Calif. ophiolite divide the uniform suite of pillowed and massive lavas into the lower part consisting of massive, brecciated tholeiites, an intrusive dike-sill complex, and part of a plutonic suite. The tholeiites are light REE depleted with a (Ce)N range of 6.5 to 26.0 and (Yb)N of 6.0 to 30.0; it is suggested that the tholeiites were produced by partial melting of a LREE depleted source similar to MORB. The upper part of the volcanic pile is comprised of basaltic-andesitic flows and interbedded coarse to fine volcanic sediments; these 'calc-alkaline' rocks are light REE enriched with the (Ce)N range of 17.0-28.0 and (Yb)N of 8.0 to 12.0. Finally, petrographic investigations of volcanic sediments and sulfide ore deposits in the lava show that the ophiolite formed near a group of active submarine and subareal volcanoes.

Menzies, M.↗
NASA NTRS1980

Genesis of highland basalt breccias - A view from 66095

Electron microprobe and defocused beam analyses of the lunar highland breccia sample 66095 show it consists of a fine-grained subophitic matrix containing a variety of mineral and lithic clasts, such as intergranular and cataclastic ANT, shocked and unshocked plagioclase, and basalts. Consideration of the chemistries of both matrix and clasts provides a basis for a qualitative three-component mixing model consisting of an ANT plutonic complex, a Fra Mauro basalt, and minor meteoric material.

Garrison, J. R., Jr.↗