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Albee, A. L.

Publications and source records attributed to Albee, A. L..

50 records · Page 3

Petrology and origin of Boulders no. 2 and no. 3, Apollo 17 Station 2

The paper presents petrographic and mineralogical data for five samples from Boulder 2 (72315, 72335, 72355, 72375, and 72395) and sample 72435 from Boulder 3 at Apollo 17 Station 2. All the samples were found to consist of a few percent megaclasts set in a fine-grained matrix, which is comprised of microclasts and a poikilitic to subophitic-textured groundmass that crystallized from a melt. The samples have similar modal mineralogies, mineral compositions, and bulk-chemical compositions.

Dymek, R. F.

Petrogenesis of lunar rocks: Rb-Sr constraints and lack of H2O

Rb and Sr isotopic data and other chemical data indicate major lunar differentiation at about 4.6 AE and very limited subsequent differentiation. The constraints of limited differentiation post 4.6 AE and the apparent lack of H2O on the moon, when applied to the derivation and petrogenesis of lunar samples, suggest the following: (1) soil samples, breccias, metaclastic rocks, and feldspathic basalts represent mixtures of repeatedly-modified clastic material, which was ultimately derived from materials formed during the about 4.6 AE differentiation; and (2) mare basalts crystallized from melts which formed by partial melting and, which developed without equilibration between the melt and crystalline residuum.

Albee, A. L.

Mineralogy, petrology, and chemistry of basalt fragments returned by Luna 16

Mineralogical, petrological, and chemical analyses, along with Rb-Sr age and Ar-40/Ar-39 measurements, were carried out with the B-1 sample returned from the Luna 16 mission. The sample, weighing 62 mg, is a fine-grain basalt of ophitic structure. It differs from the Apollo samples in that the pyroxene and plagioclass contents are almost identical, and the ilmenite content (7%) lies between those of the Apollo-11 and Apollo-12 samples. Chemically, it is characterized by a high Sr content and a high K/U ratio.

Albee, A. L.

Constrained least-squares analysis of petrologic problems with an application to lunar sample 12040.

Many petrologic problems, which may be expressed as a set of linear equations, have been solved by least-squares analysis. In many cases insufficient attention has been paid to the physical conditions of the model resulting in incorrect application of the method. This paper presents a systematic treatment of the application of least-squares analysis to petrologic problems including the direct utilization of physical constraints and weighting factors in the problem, and the assessment of uncertainties in the solution. As an example, least-squares analysis is used to examine, in detail, the mass balance equations for lunar rock 12040 and to determine the consistency of the available analytical data.

Reid, M. J.

Comparative petrology of Apollo 16 sample 68415 and Apollo 14 samples 14276 and 14310.

Petrographic and electron microprobe studies of Apollo 16 igneous rock 68415 and Apollo 14 rocks 14276 and 14310 show that all three samples differ from the mare basalts and are characterized by plagioclase as the first liquidus phase and by the abundance of plagioclase which is in part cumulate in origin. Major and minor element abundances and isotopic data prohibit the derivation of rocks like any of these samples from one another by magmatic fractionation during their crystallization. They could have originated by partial melting of an old, more Al-rich source material without isotopic equilibration with the residuum, by complete melting of three independent sources, or by contamination with old radiogenic material. The existence of such feldspathic basalts indicates that the generation of Al-rich magmas may have been an important and widespread lunar process.

Gancarz, A. J.

Mineralogy, petrology, and chemistry of a Luna 16 basaltic fragment, sample B-1.

Petrological, mineralogical, and chemical investigations of the B-1 Luna 16 sample have revealed that the sample is a fine-grained ophitic basalt which is distinguished from the Apollo samples by containing a single pyroxene, an ilmenite content intermediate to that of the Apollo samples, and subequal amounts of pyroxene and plagioclase. It is also distinguished by a high Sr content and a high K/U value.

Albee, A. L.

Uranium-bearing minerals of lunar rock 12013.

The U distribution in rock 12013 was studied by fission track and elemental mapping techniques. Major U-bearing phases are whitlockite, apatite, zircon, and phase beta, which is a Zr-Ti mineral rich in Fe, Nb, Y, REE, and containing up to 3.6% UO2, 4.7% ThO2 and 4.2% PbO. Calculated microprobe ages for phase beta average 4.0 b.y. and are in reasonable agreement with Rb-Sr and K-Ar ages. Phase beta plays a significant role in the U-Th-Pb systematics of rock 12012 and may play a similar role in the model ages of lunar soil.

Haines, E. L.

Petrologic and mineralogic investigation of some crystalline rocks returned by the Apollo 14 mission.

Apollo 14 crystalline rocks (14053 and 14310) and crystalline rock fragments (14001,7,1; 14001,7,3; 14073; 14167,8,1 and 14321,191,X-1) on which Rb/Sr, Ar-40/Ar-39, or cosmic ray exposure ages have been determined by our colleagues were studied with the electron microprobe and the petrographic microscope. Rock samples 14053 and 14310 are mineralogically and petrologically distinct from each other. On the basis of mineralogic and petrologic characteristics all of the fragments, except 14001,7,1, are correlative with rock 14310. Sample 14073 is an orthopyroxene basalt with chemical and mineralogic affinities to ?KREEP,' the ?magic' and ?cryptic' components. Fragment 14001,7,1 is very similar to Luny Rock I.

Gancarz, A. J.