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At least 253 records · Page 14

Timber resource information system

The author has identified the following significant results. The investigators are convinced that high altitude photography when supported with ground measurements and existing surveys, contain all the resource data needed for overall land management planning. This overall planning would include land use classification, environmental impact statements, and similar documentation. First inspection of the RBV ERTS imagery on the Quinault Reservation shows that much of the cultural and resources detail can be identified. Of particular note, is the obvious contrast between recently harvested timber cutting blocks as opposed to those cut more than a year ago. The RBV color composite would have been of better definition if Band 3 had been excluded.

Woll, A. M.↗

Timber resources information system

The author has identified the following significant results. The investigators are convinced that high altitude photography when supported with ground measurements and existing surveys, contains all the resource data needed for overall land management planning. This overall planning would include land use classification, environmental impact statements, etc. First inspection of the ERTS-1 RBV imagery on the Quinault Reservation shows that much of the cultural and resource detail can be identified. Of particular note, is the obvious contrast between recently harvested timber cutting blocks as opposed to those cut more than a year ago. The RBV color composite would have been of better definition if band 3 had been excluded. Land managers are disappointed at first viewing ERTS-1 imagery in that it is not stereoscopic and find the scale and resolution at the 9 x 9 format difficult to interpret or translate to their ground truth. Arrangements are being made to have 1:250,000 enlargement prints made for their use.

Woll, A. M.↗

The origin of the moon and solar system.

The Rb-87/Sr-87 ages of many of the lunar rocks suggest that the fundamental differentiation took place 4.5 b.y. ago and that remelting occurred without exchange of the rubidium and strontium with the surroundings. The Apollo A rocks are an exception to this. They appear to have acquired rubidium without all of the Sr-87 produced during the first aeon. Also in the remelting about half of the radiogenic leads were lost to the surroundings by a vaporization process. We interpret these results to mean that remelting occured in a system that was nearly closed to the surroundings and that the high early concentrations of radioactive elements in highly insulating surroundings made this possible.

Urey, H. C.↗

Transferring technology to the public sector.

Approximately four years ago the Jet Propulsion Laboratory, under NASA sponsorship, began to devote some of its resources to examining ways to transfer space technology to the civil sector. As experience accumulated under this program, certain principles basic to success in technology transfer became apparent. An adequate definition of each problem must be developed before any substantial effort is expended on a solution. In most instances, a source of funds other than the potential user is required to support the problem definition phase of the work. Sensitivity to the user's concerns and effective interpersonal communications between the user and technical personnel are essential to success.

Alper, M. E.↗

Apollo - The scientific payoff.

A great deal of information regarding the composition and the age of the lunar surface has been obtained as a result of the Apollo mission. It has been found that the moon cannot have evolved as a cold planet, but had a history of intense and voluminous volcanism for the first 1.5 billion years of its life. The moon appears to have cooled rapidly at some stage soon after three billion years ago. The evidence indicates that the lunar mantle is solid down to at least 800 km.

Ridley, I.↗

Pyroxenes from breccia 14303.

Review of the investigation results obtained on the adjacent polished thin sections 47 and 53 of breccia 14303, the largest rock returned by Apollo 14 for which a location has not been established. A basaltic lithic clast, composed mainly of plagioclase, olivine, and pigeonite zoned to subcalcic augite, is found to occupy the same relative position in both sections and is assumed to represent a single lithic chip. Further study of lithic and fragmental clasts in breccias is seen likely to yield information on lunar history between 4.6 and 3.9 b.y. ago.

Weigand, P. W.↗

Deformation of silicates in some Fra Mauro breccias.

The results of the studies conducted show that there is no unequivocal evidence for appreciable static deformation (other than annealing) in the Fra Mauro formation. These rocks probably have been derived from depths to about 10 km. It is suggested that there has been no substantial tectonic activity in the range from the surface to 10 km since these rocks and those of the other Apollo sites crystallized some 3 to 4 billion years ago. This negative conclusion implies that at least the outer layer of the moon has been static for this length of time.

Lallemant, H. G. A.↗

The extralunar component in lunar soils and breccias.

Concentrations of Ni, Zn, Ga, Ge, Cd, In, and Ir in soils and breccias returned by Apollo 14 and Apollo 15 are reported. The integrated flux of extralunar material at each lunar landing site is estimated on the basis of the siderophilic elements Ni, Ge, Ir, and Au. It falls with time between 3.95 and 3.26 g.y. before the present. The flux versus time relationship indicated by the trace element data is consistent with estimates of the same relationship based on crater statistics and morphologies, as would be expected if the same populations of interplanetary objects were responsible for both properties. The data are consistent with the presence of two populations of material bombarding the moon early in its history, one with a short half-life that was dominant until about 3.8 g.y. ago, and another with a half-life of about 2.0 g.y. that dominated during the more recent era.

Baedecker, P. A.↗

U-Th-Pb and Rb-Sr measurements on some Apollo 14 lunar samples.

The concentrations of selected elements and elemental ratios in some Apollo 14 samples are presented in a table. Another table shows the isotopic composition of lead and strontium in some Apollo 14 samples. Graphs are provided with lead isotope ratio plots and a strontium evolution diagram. Rb-Sr ages are discussed together with isochron age methods of U-Th-Pb, a primary Pb-Pb isochron, a secondary Pb-Pb isochron, U-Pb concordia age relations, and U-Th-Pb concordia relations. Breccias and some soil samples as well as a basalt sample give evidence of significant enrichment of lead relative to uranium and thorium billions of years ago at the Fra Mauro site.

Tatsumoto, M.↗

Solar flare and galactic cosmic ray studies of Apollo 14 and 15 samples.

Thermoluminescence (TL) measurements in rock 14310 show a strong depth dependence consistent with that expected from solar flares. This effect should prove useful in studying solar flare fluctuations in the time interval of 100 to 100,000 years. Rare gas spallation ages for rock 14301, 14306, and 14311 are respectively 102 plus or minus 30, 25 plus or minus 2, and 661 plus or minus 72 m.y. The 14306 value supports the idea that Cone Crater was formed 25 million years ago. Groupings of exposure ages suggest the dates of other major cratering events. Galactic track data in 14310 show little depth dependence.

Crozaz, G.↗

Charge and energy spectra of cosmic rays with Z equal to or greater than 30.

A 2 g/sq cm stack (22 sq m in area) containing 41 plastic sheets, one G-5 emulsion, and one high-speed Cerenkov film detector was launched by balloon from Minneapolis on Sept. 4, 1970. The stack received an effective exposure of 48 hr at 2.8 mbar and a cutoff rigidity of about 1.8 GV. The abundance ratios relative to Fe are reported for various charges and charge groups from Z = 29 to 105 on the basis of 70 presently measured events as well as previously obtained results. Between Fe and the Pt peak, the cosmic ray abundances appear to be similar to solar system abundances; the heavier nuclei are strongly overabundant and appear to have originated about 10 m.y. ago in a rapid neutron capture process.

Kobetich, E. J.↗

Lunar volcanism - Age of the glass in the Apollo 17 orange soil.

Glasses on the moon can form either by impact or by volcanic processes. An age determination indicates that the glass of the orange soil formed close in time to the volcanic activity in the Sea of Serenity about 3,750 million years ago. The orange soil was certainly not formed by a recent fumarole. The young exposure age, about 32 million years, found for the glass of the orange soil is in agreement with its fresh appearance on the lunar surface.

Husain, L.↗

Spatial distribution of Ar-40/Ar-39 ages in lunar breccia 14301.

The distribution of stable and radioactive argon isotopes in a lunar breccia has been measured in situ by laser probe mass spectrometry. This new technique determines the spatial distribution of Ar-40/Ar-39 ages on less than .1 milligram of material. Calculated Ar-40/Ar-39 ages of clasts within this breccia are 3.7 and 2.9 b.y. Parentless radiogenic Ar-40 exists within the fine-grained matrix and appears to have been trapped simultaneously with solar argon. This 'atmosphere' of ambient gas appears to have been incorporated into the rock by an impact event not more than 3 b.y. ago.

Megrue, G. H.↗

Apollo 16 neutron stratigraphy.

The Apollo 16 soils have the largest low-energy neutron fluences yet observed in lunar samples. Variations in the isotopic ratios Gd-158/Gd-157 and Sm-150/Sm-149 (up to 1.9 and 2.0%, respectively) indicate that the low-energy neutron fluence in the Apollo 16 drill stem increases with depth throughout the section sampled. Such a variation implies that accretion has been the dominant regolith 'gardening' process at this location. The data may be fit by a model of continuous accretion of pre-irradiated material or by models involving as few as two slabs of material in which the first slab could have been deposited as long as 1 b.y. ago. The ratio of the number of neutrons captured per atom by Sm to the number captured per atom by Gd is lower than in previously measured lunar samples, which implies a lower energy neutron spectrum at this site. The variation of this ratio with chemical composition is qualitatively similar to that predicted by Lingenfelter et al. (1972). Variations are observed in the ratio Gd-152/Gd-160 which are fluence-correlated and probably result from neutron capture by Eu-151.

Russ, G. P., III↗

Evaluation of ERTS data for certain oceanographic uses

The author has identified the following significant results. (1) Sunglint effects over water can be expected in ERTS-1 images whenever solar elevations exceed 55 deg. (2) Upwellings were viewed coincidently by ERTS-1 and NOAA-2 in Lake Michigan on two occasions during August 1973. (3) A large oil slick was identified 100 km off the Maryland coast in the Atlantic Ocean. Volume of the oil was estimated to be least 200,000 liters (50,000 gallons). (4) ERTS-1 observations of turbidity patterns in Lake St. Clair provide circulation information that correlates well with physical model studies made 10 years ago. (5) Good correlation has been established between ERTS-1 water color densities and NOAA-2 thermal infrared surface temperature measurements. Initial comparisons have been made in Lake Erie during March 1973.

Strong, A. E.↗

A study of morphology, provenance, and movement of desert sand seas in Africa, Asia, and Australia

The author has identified the following significant results. The regional studies of sand seas made possible by analysis of ERTS-1 imagery have established that widespread patterns of eolian sand deposition exist in many places and that similarities and differences in these patterns can be measured and compared, on a worldwide scale. Analysis of the relationships of depositional patterns to controlling factors will require completion of the color mosaics of the test sites, and acquisition of adequate supporting ground truth data, especially wind data. Once analyses are complete, the results will be applicable to the regional study of ancient eolian sandstones. Such sandstones were formed many millions of years ago under conditions believed to be identical to those under which the sand seas that are observed being formed today. The understanding of the deposition of eolian sands provided by analysis of ERTS-1 imagery will be applicable to an understanding of the structure and distribution of ancient eolian sandstones and their potential as reservoirs of oil and water.

Mckee, E. D.↗

Recommended reference figures for geophysics and geodesy

Specific reference figures are recommended for consistent use in geophysics and geodesy. The selection of appropriate reference figure for geophysical studies suggests a relationship between the Antarctic negative gravity anomaly and the great shrinkage of the Antarctic ice cap about 4-5 million years ago. The depression of the south polar regions relative to the north polar regions makes the Southern Hemisphere flatter than the Northern Hemisphere, thus producing the third harmonic (pear-shaped) contribution to the earth's figure.

Khan, M. A.↗

Relative ages of some near-side Mare units based on Apollo 17 metric photographs

Relative flux ages were determined for 110 areas on parts of Serenitatis, Vaporum, and Imbrium, using Apollo 17 metric photographs. The crater-morphology technique for determining relative ages is described. It is concluded that these maria formed over an interval of 1.5 billion years, extending from 3.7 to 2.2 billion years ago.

Boyce, J. M.↗