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Wood, J. A.

Publications and source records attributed to Wood, J. A..

53 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

The Haveroe ureilite - Petrographic notes.

Review of the mineralogy and texture of the Haveroe and of some of the six other known ureilites, and assessment of the implications of their observed characteristics. In common with other ureilites, Haveroe shows mineralogical and textural evidence of preterrestrial shock. The olivines and metal grains have been recrystallized, the fabric includes angular voids, and graphite-rich areas are present that have been partially converted to diamonds with some indication of lonsdaleite. On the basis of such features, a subdivision of ureilites into particular types is proposed.

Marvin, U. B.↗
NASA NTRS1972

Thermal history and early magmatism in the moon.

Lunar heat-flow calculations are carried out for a model moon in which (1) near-surface initial temperatures are very high (as the occurrence of a surface anorthositic layer seems to require), and (2) heat-generating radionuclides are transported upward when melting occurs. Near-surface regions are found to cool and then experience a resurgence of high temperature, as radionuclide-rich magmas from the lunar interior accumulate near the surface. This peaking of near-surface temperature can be brought into correspondence with the episode of vulcanism that gave rise to the basalts represented in the Apollo samples, if we assume relatively high lunar temperatures in early times (due to high initial temperatures, or a high content of radioactive elements, or both).

Wood, J. A.↗
NASA NTRS1972

Luna 16 - Relative proportions and petrologic significance of particles in the soil from Mare Fecunditatis.

Some 2380 lithic and vitreous particles from levels A and G of the Luna 16 core-tube sample were classified. The relative proportions of particle types from each of the two layers are reported, and some petrological and mineralogical aspects of the lithic and vitreous components of the lunar regolith are discussed. Possible sources of the particles in the Luna 16 soil are examined.

Reid, J. B., Jr.↗
NASA NTRS1972

Noritic fragments in the Apollo 14 and 12 soils and the origin of Oceanus Procellarum.

Fragments of noritic breccias having a range of recrystallization textures and noritic basalts comprise about 80% of the 1 to 2 mm soil samples from Cone Crater (14142) and the bottom of the trench (14151). In five other samples, noritic fragments range in abundance from 42 to 56%. The remaining particles in each case are glasses, soil breccias, and glass-bonded aggregates; other crystalline rock types such as anorthosites constitute less than 1% of the soil. Noritic materials - i.e., Apollo 12 and 14 norites and ropy (KREEP) glass particles, can be divided into two broad groups on a chemical basis. The particles in one group have relatively high bulk TiO2 contents and high Fe/(Fe + Mg) ratios in their normative pyroxenes; the ropy glasses from Apollo 12 and 14 and a few Apollo 12 noritic rock fragments are in this category. Particles in the other class contain pyroxenes with a lower Fe/(Fe + Mg) and have a range of TiO2 contents; most noritic rock fragments from Apollo 12 and 14 are in this group. The ropy glasses may be from Copernicus or other rayed craters, but almost all the norites derive from the Fra Mauro formation or other noritic occurrences associated with Oceanus Procellarum.

Taylor, G. J.↗
NASA NTRS1971

Petrological character of the Luna 16 sample from Mare Fecunditatis.

A total number of 1858 lithic and vitreous fragments from the Luna 16 core-tube sample are classified. The fragments were taken from soil fractions ranging in size from 150 to 425 microns at levels A and G. No important differences are observed between the proportions of particle types in levels A and G, nor between the soils of Luna 16 and those from the Apollo 11 landing site in the nearby Mare Tranquillitatis.

Wood, J. A.↗