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Stuart-Alexander, D. E.

Publications and source records attributed to Stuart-Alexander, D. E..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Geologic-magnetic correlations on the moon - Apollo subsatellite results

Comparison of the magnetic-field measurements of the Apollo subsatellite magnetometers with USGS geologic maps suggests that the ancient lunar field may have been greater during the Imbrian Period than the earlier Pre-Nectarian and Nectarian periods. Further, the field seems to have varied in direction. These data are consistent with a model in which the ancient lunar magnetizing field arises from a core dynamo which does not form until the Imbrian Period. Impacts during this period then result in magnetized crater melt and ejecta blankets. It is emphasized, however, that the area sampled by the subsatellite magnetometers is but a small fraction of the lunar surface. These results must be confirmed with studies of independent regions of the lunar surface before they can be considered conclusive.

Russell, C. T.↗
NASA NTRS1975

Lunar magnetic anomalies and the Cayley Formation

Correlation between the Cayley Formation and the magnetic anomaly at the Apollo 16 site in the northern plains of the crater Van de Graaf is discounted. The planar fill in the north end of Van de Graaf is described as dissimilar from Cayley-like plains, and orbital magnetic data collected by Apollo sub-satellites is shown not to substantiate the correlation of Cayley-like plains with any particular magnetic signature. The magnetic anomaly near Van de Graaf is explained as most likely being due to a subsurface source.

Stuart-Alexander, D. E.↗
NASA NTRS1973

Apollo 16 rocks - Petrology and classification.

The Apollo 16 rocks are classified in three broad intergradational groups: (1) crystalline rocks, subdivided into igneous rocks and metaclastic rocks, (2) glass, and (3) breccias, which are subdivided into five groups on the basis of clast and matrix colors. Most of the rocks were derived by impact brecciation of an anorthosite-norite suite but may represent ejecta from more than one major basin. First-cycle breccias are believed to have consisted of clasts of crushed anorthosite-norite in a fine-grained partly fused matrix with a chemical composition similar to that of the clasts. Most of the other recognized breccia types could have been produced by rebrecciation of first-cycle breccias.

Wilshire, H. G.↗