bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of the Meteoritic Falls of the World: 7. Numbers and Percents of Observed and Unobserved Falls of All Classes
Authors: Leonard Frederick C. 
Published: June 2012

ABSTRACTThe substance of this paper is comprized within 2 tables entitled respectively. “1. Numbers and Percents of Observed and Unobserved Falls of All Classes,” 1220 falls in all, recorded in Coulson's “Catalogue of Meteorites” (1940), and “2. Frequencies of Minimum and Maximum Percents of Observed Falls of the Principal Classes.” The data of these tables are briefly reviewed, and several conclusions are stated. It is a noteworthy if not a remarkable fact that at least one representative of every known variety of aerolite has been observed to fall; this suggests, among other things, that aerolitic material may be present on the Earth which has not been recognized as such, simply because no sample of it has been seen to fall.
A Report on Dust Collections Made at Mount Weather and Arlington, Virginia, 1 October to 20 November, 1946
Authors: Landsberg H. E. 
Published: June 2012

ABSTRACTProcedures employed in the collection of atmospheric dust during the interval 1 October to 20 November, 1946, are described. Details are given on the microscope technique used in the examination of the dust collected. From an analysis of the results obtained, arguments are adduced favoring the hypothesis that certain of the dust particles collected were of cosmic origin.
Sampling Theory Applied to Meteoritic Populations
Authors: La Paz Lincoln 
Published: June 2012

ABSTRACTMeteoriticists have long believed in the existence of areal anomalies in the horizontal distribution of meteorites. On the one hand, the significantly different proportions in which iron and stone meteorites are found in samples of the total meteoritic populations of the eastern and western hemispheres have repeatedly called forth the statement that such an anomaly, having an origin somehow connected with geographical location, exists between the hemispheres. On the other hand, Högbom has conjectured that a similar areal anomaly, having its origin not in geographical location, but rather in the local selective depletion of native‐iron meteorite‐populations by the agency of man is found on comparing the meteoritic populations of the Old (or long‐inhabited) World and the New. This second partition of the globe into subregions is distinct from the separation into eastern and western hemispheres.The present paper critically subjects the evidence for these suggested anomalies to analysis, by use of the sampling theory developed in the study of discrete, 2‐fold populations. Such an approach is possible only because of the recent publication by Frederick C. Leonard and Boris Slanin17 of invaluable compilations relating to the areal distribution of all recovered meteorites. On the basis of the exhaustive sampling data thus supplied, the following conclusions have been reached: Denote by W a meteoritic population derived from witnessed falls and by U such a population derived from unwitnessed falls; then no significant difference as regards the incidence of stony character exists between (1) the W's of the eastern and western hemispheres; (2) the U's of these hemispheres; (3) the W's of the Old and New Worlds; and (4) the U's of the same subregions. The analysis carried out makes clear also that current belief in areal anomalies stems from the logically indefensible practice of lumping together the U and W populations of each of the distinct geographical areas compared.
The Oxide Crust of the Willamette, Oregon, Meteorite
Authors: Morley Russell A. 
Published: June 2012

ABSTRACTMore than 8,500 gm. (15 1/4 lb.) of the oxidized crust of the Willamette, Clackamas Co., Oregon, siderite (C.N. = 1226,454; cl. = Om) have been recovered from the recently excavated crater in which that meteorite lay. This material, of hardness 6 and average specific gravity about 3.8, is described, and the disposition that has been made of it is recorded.
A Preliminary Report on the Mineralogy of the Norton County, Kansas‐Furnas County, Nebraska, Achondrite (1000,400)
Authors: Beck Carl W. , La Paz Lincoln 
Published: June 2012

ABSTRACTThis paper presents a preliminary report on the friable enstatite achondrite, with nickel‐iron inclusions, more than a ton of which fell in Norton County, Kansas, and Furnas County, Nebraska, on 1948 February 18 (C.N. = 1000,400). Megascopically, the achondrite resembles a rhyolite porphyry, the fine‐grained groundmass of grayish‐white color containing phenocrysts of 2 types, the first, a light‐gray mineral exhibiting cleavage at angles of 88° and 92°, the second, a clear, glassy mineral which does not cleave or part, but rather shatters with a conchoidal fracture. Under closer examination, both the groundmass and the phenocrysts of the stone are found to consist chiefly or solely of a very pure enstatite. In addition to inclusions of nickel‐iron, the achondrite contains abundant small flakes of graphite, and a brown, platy mineral, identified tentatively as diallage. For both the cleavage enstatite and the glassy enstatite, α = 1.652, β = 1.654, γ = 1.660; and, furthermore, the other optical constants are the same, except that the axial angle found for the glassy enstatite (80° to 85°) is more than twice that found for the cleavage enstatite (40°). Primary, secondary, and tertiary fusion crusts, ranging in thickness from at least 17.7 mm. down to less than 0.2 mm., have been found on the achondrite. Those portions of the fusion rind so far examined microscopically in oil immersions were found to be extremely fine‐crystalline, and not glassy, and they had an average index of refraction of 1.656.
The Mineralogy and Origin of Josephinite*
Authors: Morley Russell A. 
Published: June 2012

ABSTRACTJosephinite is a naturally‐occurring, terrestrial nickel‐iron alloy, found along Josephine Creek, Josephine County, Oregon, and associated with stream gravels as water‐worn pebbles, sometimes ellipsoidal in shape. A group of more than 75 specimens examined gave the following physical and chemical data: average sp. gr., 5.66; hardness, 4.5 to 5.0; streak, lead‐gray; luster, metallic; fracture, hackly; malleable, sectile; strongly magnetic; opaque. The group of specimens examined ran as follows: largest dimension, 3.2 mm. to 31.4 mm. The chemical formula for josephinite is written usually as Fe2Ni5, altho josephinite contains also a little cobalt, phosphorus, and sulfur.
A Preliminary Report on the Distribution of Gallium, Palladium, Gold, and Nickel in 45 Iron Meteorites*
Authors: Brown Harrison , Goldberg Edward 
Published: June 2012

ABSTRACT AND INTRODUCTIONWe have completed the analysis of 45 iron meteorites (siderites) for gallium, palladium, gold, and nickel, utilizing the neutron activation method of analysis for the first three elements named.1,2 Nickel was determined by the method employed by Henderson,3 and good checks were obtained with his analyses. The iron meteorites studied cover the complete range of classes, hexahedrites, octahedrites, and ataxites. Our results will be published in detail at a later date. In the meantime, certain features of the distributions are of sufficient interest to warrant a preliminary report.
The Weatherford, Oklahoma, Meteorite (ECN =+988,358)*
Authors: Beck Carl W. , Lapaz Lincoln 
Published: June 2012

ABSTRACTIn this paper are given details concerning the discovery of an unusual irony‐stone meteorite near Weatherford, Custer County, Oklahoma (equatorial coördinate number (ECN) = +988,358). There is some evidence that the specimen recovered is only a fragment of a much larger mass, but neither visual nor instrumental searches have led to additional recoveries. Consequently, the mineralogical and chemical investigations have necessarily been based upon the examination of the single specimen so far discovered, that found by Mr. A. B. Potter in 1926. On the basis of these investigations, which are detailed in the paper proper, the meteorite has been classified as a siderolite of class sideraerolite (S) and subclass mesosiderite (Sms).
A Possibly Meteoritic Dust‐Cloud
Authors: La Paz Lincoln 
Published: June 2012

AbstractThis note contains a quoted account of an extraordinary observation made by Captain W. L. Stewart of the British Overseas Airways Corporation, on 1948 February 7, at 11h 45m U.T., while he was flying west‐bound at an elevation of 10,000 feet, over a point whose equatorial coördinate number (ECN) = +0209,550, of what was apparently a downwardly concave, cylindrical dust‐cloud with a length of nearly 60 miles, which may have been meteoritic in origin.
On the Identification and the Recovery of the Goose Lake, California, Siderite (ECN =+1205,420)
Authors: Leonard Frederick C. 
Published: June 2012

AbstractJust to keep the record straight, and in justice to all concerned, the historical facts regarding the identification and the recovery of the Goose Lake, California, siderite, the fourth‐largest known meteorite of the United States, are herein briefly repeated.
The Real and Apparent Stellar Magnitudes of Telescopic Meteors
Authors: Wylie C. C. 
Published: June 2012

AbstractSix (6) dual observations of meteors, made with the naked eye and with a telescope or binoculars, are discussed. It is found that one (1) was a “point” meteor. Two (2) were “line” meteors seen with the telescope or binoculars before being noticed with the naked eye and at below‐the‐naked‐eye magnitude. Three (3) were “line” meteors, for which the binocular and the naked‐eye observers recorded essentially the same real magnitudes.
Experiments on the Etching of Siderites
Authors: Buddhue John Davis 
Published: June 2012

ABSTRACTA number of old and new etching reagents for meteorites have been tested. None was found to be superior to those already in general use, except that the recent report that the addition of a little glue gives improved results is confirmed. Some other colloidal additives also were found to give a better etch, but none was better than glue. A few other experiments also are briefly mentioned. All workable reagents give the same kind of figures.
Constructional Names and Symbols for the Subclasses in the Simplified Classification of Meteorites*
Authors: Leonard Frederick C. 
Published: June 2012

ABSTRACTConstructional names and symbols for all 32 of the subclasses of meteorites recognized in the simplified classification are given. These names and symbols indicate, in each case, the general structure and mineral composition of the comprized meteorites. The paper contains 4 tables: (1) 20 qualifying symbols or qualifiers; (2) symbols for the 16 minerals commonly occurring in meteorites; (3) symbols for 24 other minerals found in meteorites; and (4) the 32 subclasses of meteorites and their symbols. Some 13 subclasses that have been excluded from the simplified classification, and both “composite” and “transitional” meteorites are condensedly discussed. Finally, the classificational sequence of meteorites, which is a sequence primarily of increasing density from left to right, is written out, in terms of the new constructional symbols, for all 32 of the subclasses in the simplified classification, and the sequence is briefly reviewed.
SIZE AND SPACIAL DISTRIBUTION IN METEORITIC SHOWERS
Authors: Frost Michael J. 
Published: June 2012

Size distribution in the Barwell, Bruderheim, Gibeon, Johnstown, Sikhote‐Alin and Tenham showers is studied. On the assumption that the distribution follows the Gates‐Gaudin‐Schumann law, which describes artificially crushed material, it is estimated that 80% of the fine material of the Gibeon shower was not collected; for the other showers the figure varies between 52 and 61%.The spacial distribution pattern of the Barwell, Johnstown, Krymka, Kunashak, Leedey, Plainview (1917), and Sikhote‐Alin meteoritic showers is studied. It is established that the patterns show considerable regularity and that the distribution pattern of fragments of any one size is a function of the sorting factor, which is the distance in kilometers between groups of fragments whose mass differs by an order of magnitude.
MINERALOGY AND CHEMISTRY OF THE KYLE, TEXAS, CHONDRITE
Authors: Fodor R. V. , Keil Klaus , Jarosewich E. , Huss G. I. 
Published: June 2012

The Kyle, Texas, U.S.A., chondrite was identified in 1965. Electron microprobe analyses and microscopic examination show the following mineralogy: olivine (Fa 26.2 mole %), orthopyroxene (Fs 21.0 mole %), clinopyroxene, plagioclase (An 10.3 mole %), chlorapatite, whitlockite, kamacite, taenite, troilite, chromite, and an iron‐bearing terrestrial weathering product. Eutectic intergrowths of metaltroilite and a brecciated matrix indicate that the Kyle chondrite was shocked. Recrystallization and shock have obliterated chondrule‐matrix boundaries.A chemical analysis of the meteorite shows the following results (in weight %): Fe 0.38, Ni 1.22, Co 0.05, FeS 5.98, SiO2 38.41, TiO2 0.11, Al2O3 2.13, Cr2O3 0.55, Fe2O3 8.02, FeO 14.83, MnO 0.31, MgO 23.10, CaO 1.60, Na2O 0.74, K2O 0.08, P2O5 0.19, H2O+ 1.73, H2O− 0.37, C 0.03, Sum 99.83. On the basis of bulk chemistry, composition of olivine and orthopyroxene, and the recrystallized matrix, the Kyle meteorite is classified as an L6 chondrite.
HAVERÖ UREILITE: EVIDENCE FOR RECRYSTALLIZATION AND PARTIAL REDUCTION
Authors: Wlotzka F. 
Published: June 2012

Haverö consists of large olivine areas with a pavement structure and single crystals of twinned clinopyroxene. Black veins with sharp boundaries traverse the silicates. They contain graphite, diamond, and kamacite. In olivine a reaction rim is formed around these veins containing Ni‐poor metal and showing a lower FeO content than farther away from the vein. The CaO content of olivine and pyroxene, 0.27% and 1.7%, respectively, are higher than in these minerals in normal chondrites. The mole percent Fe + Ca/Fe + Ca + Mg in unchanged olivine and in pyroxene agree with the range of L‐chondrites. Metal occurs in three types: a, larger grains in the course of the black veins, they contain 2 to 3% Ni; b, micron‐sized grains inside the black veins and its reaction rim; c, medium‐sized grains with ∼0.7% Ni in olivineThe interpretation of these observations is: a material similar to an L‐chondrite was reheated and recrystallized (at this time it may have lost its feldspar, metal and troilite by partial melting), Ca was redistributed and partly retained in olivine and pyroxene due to rapid cooling, a late introduction of carbon into veins caused a partial reduction of FeO in olivine and formation of Ni‐poor metal
THERMAL FATIGUE: A POSSIBLE SOURCE OF STRUCTURAL MODIFICATIONS IN METEORITES
Authors: Levi F. A. 
Published: June 2012

Periodic thermal excursions, even in a low‐temperature range, may cause internal stresses and give origin to some of the observed plastic and clastic deformations in stony meteorites.An experimental test confirms our hypothesis: lattice distortions, cleavage and cracking were artificially induced in specimens of two H‐chondrites (Mills and Bur‐Gheluai) by low‐temperature “thermal fatigue.” The observed effects appear to be increasing with increasing number of cycles.
THERMOLUMINESCENCE AND THE TERRESTRIAL AGE OF METEORITES
Authors: Sears D. W. , Mills A. A. 
Published: June 2012

The use of thermoluminescence (TL) to determine the terrestrial age of meteorites is investigated. It is found that meteorites can be divided into two groups. One group, in which members lose their low temperature TL rather rapidly (the “low retentivity” group), may be dated up to about 100 years after fall, although with little accuracy. The other (the “high” group) is more retentive, and may still be dated several hundred years after fall. A meteorite of unknown date of fall may be assigned to the high or low group by laboratory determination of the rate of decay of the low temperature TL.Weathering coats the grains with limonite and lowers the intensity of the TL. The percentage reduction is constant for various intensities, but the peak height ratio is changed. Therefore, for weathered specimens, a method which examines the decrease in the intensity of a single peak is preferred to one which depends upon peak height ratios: this is made possible by artificially irradiating the meteorites. The following terrestrial ages for finds were obtained: Plainview 225–300 years; Dimmitt 280–330 years; Calliham 350–400 years. Bluff, Etter, Potter, Shields and Wellman (c) proved to be too old to be dated by our methods (≥ 500 years). None of the low group finds available to us proved to be young enough to be dated precisely. Terrestrial ages indicate an extremely low efficiency of recovery (≤ 1%) for meteorites that are not seen to fall.Artificially irradiating the meteorites also revealed the fact that 9 of our 19 meteorites were saturated with respect to thermoluminescence when they entered the atmosphere, and therefore that a technique based on this phenomenon would not be applicable to such specimens to obtain their cosmic ray exposure age.
COMPOSITIONAL STUDY OF THE LONE TREE, IOWA, CHONDRITE
Authors: McCormick G. R. , Carman J. H. 
Published: June 2012

A meteorite, named for the location of its discovery near Lone Tree, Iowa, was found by Loren Westfall in May 1971. Electron microprobe and petrographic studies reveal its mineral composition to be olivine, low‐calcium clinopyroxene, high‐calcium clinopyroxene, troilite, kamacite, taenite and iron oxides.On the basis of texture, olivine composition (19% Fa), low‐calcium clinopyroxene composition (17% Fs, 2% Wo) and metal (determined by modal analysis), this meteorite is classified as an H group bronzite chondrite. While it has characteristics of classes 3 and 4 (Van Schmus and Wood, 1967, Table 2) it fits class 4 better since low‐calcium pyroxene has a MD of 5.6%, olivine has a MD of 3.2%, turbid glass is present in chondrules, feldspar is absent, and the matrix is opaque. The opacity of the matrix may be due to iron oxides in microfractures in a microcrystalline matrix.
HAPPY CANYON: A NEW TYPE OF ENSTATITE ACHONDRITE
Authors: Olsen Edward J. , Bunch T.E. , Jarosewich Eugene , Noonan Albert F. , Huss Glenn I 
Published: June 2012

Happy Canyon [found: 1971, 34° 46.5′N, 101° 33.6′W, Texas] consists of about 85 vol. % enstatite (Fs 0.4%), 5 to 10 vol % plagioclase (An 26%), and 5 vol % diopside (Fs 0.9%). In addition, there are minor remnants of metal (Ni 6.35 wt %, Si‐free) and troilite (with 5.10 wt % Cr and 1.15 wt % Ti) that have survived extensive terrestrial weathering. The meteorite has a cumulate texture, uniform‐size euhedral, prismatic crystals of enstatite (0.3 to 0.4 mm long) with interstitial plagioclase, diopside, troilite, and metal. The enstatite crystals are dominantly disordered and occur in alignments that suggest flow. There are no chondrules or remnants of chondrules. The enstatite crystals contain internal negative crystal voids, which are charactieristic of enstatite achondrites, as well as internal branching submicron rivulet dislocations. The bulk composition is that of an E6 enstatite chondrite, however, it has the texture of a crystal cumulate; achondritic, but unlike that of enstatite achondrites. Glass of a granitic composition occurs mainly in the mesostasis and is compositionally like the glass found inside pyroxene crystals in the Cumberland Falls enstatite achondrite.Happy Canyon is most simply explained as an E6 composition that has melted and reprecipitated at a slightly higher oxidation state, at some depth (> 7 km), possibly in the core volume of a small, asteroidal‐size parent body. In terms of classification, it occupies the gap between the recrystallized enstatite chondrites and the igneous, crystalline, unbrecciated enstatite achondrites like Shallowater. Happy Canyon is a new type of enstatite achondrite
AN ANALYTICAL SCHEME FOR CHONDRITIC METEORITES
Authors: Hughes T.C. , Hannaker P. 
Published: June 2012

A chemical scheme is reported for the analysis of chondritic materials and results are presented for the Cocklebiddy meteorite. Analytical problems associated with chondrite inhomogeneity including phase leaching selectivity and the completeness of individual phase attack are considered. Data obtained by this method can be used to classify chondrites according to the accepted weight and molar ratio methods (Van Schmus and Wood, 1967: Wasson, 1974)The analytical scheme uses selective leaching techniques to determine, in each sample, the chemical composition of metallic, sulphide and silicate phases. Elemental concentrations are obtained by atomic absorption spectrometry, flame photometry, spectrophotometry or titration techniques, and the total sample average compositions are determined on fully oxidised specimens by XRF
CLAST‐LADEN MELT‐ROCK FRAGMENT IN THE ADAMS COUNTY, COLORADO, H5 CHONDRITE
Authors: Fodor R.V. , Keil Klaus , Prinz Martin , Ma M.‐S. , Murali A.V. , Schmitt R.A. 
Published: June 2012

The Adams County, Colorado, H5 chondrite contains a lithic fragment, 1 cm in size, that is texturally and mineralogically quite different from the chondritic host. It is composed of: a groundmass of fine‐grained euhedral to subhedral olivine (3–15 μm) and interstitial glass enclosing larger olivine and pyroxene grains (0.15‐0.5 mm; about 15 vol %); an assemblage of enstatite grains (subfragment within) and an assemblage of olivine plus orthopyroxene (a second subfragment); and about 11 vol % grains of mixed troilite and nickel‐iron metal. Analyses yielded these results: (i) olivine grains of the fragment groundmass have a compositional range (Fa12–45) and most grains contain substantial CaO and Cr2O3 (∼ 0.20 and 0.30 avg. wt%, respectively); interstitial glass has ∼ 55 wt% SiO2; (ii) larger olivine grains of the fragment are similarly high in CaO and Cr2O3 and also have a wide FeO/MgO range; one unusual pyroxene is an Mg‐rich pigeonite; (iii) the metal is martensite in composition (11–14 wt% Ni); and (iv) major and trace element analyses by INAA indicate an H‐group bulk composition for the entire 1 cm lithic fragment.On the basis of its texture and bulk and mineral compositions, the fragment is interpreted to represent unequilibrated H‐group material that was partly melted by impact. The Ca‐ and Cr‐enriched groundmass olivine and interstitial glass resulted from rapid crystallization of the chondritic melt. The Ca‐ and Cr‐enriched larger silicate grains, including the enstatite sub‐fragment and the pigeonite grain, are residual, unmelted clasts from the target material (this is supported by the presence of similar material in actual H3 chondrites). Further impact brecciation of the clast‐laden melt material, and resultant impact‐splashing accounts for the presence of the fragment in the H‐group Adams County host and documents the coexistence of unequilibrated and equilibrated H‐group material as surface regolith on one parent body.
COMPOSITION AND ORIGIN OF THE UNUSUAL OKTIBBEHA COUNTY IRON METEORITE
Authors: Kracher Alfred , Willis John 
Published: June 2012

We have analyzed Oktibbeha County, the most Ni‐rich iron meteorite, for Ni, Co, Cu, Ga, Ge, As, Sb, Ir, and Au. Cu and Sb are higher than in any other iron, but other trace elements are within the ranges typically found in iron meteorites. Extrapolation of trace element trends in group IAB indicates that Oktibbeha County is a member of this group. This sheds light on the origin of groups IAB and IIICD, which are thought to be derived from impact melts on parent bodies of chondritic composition.Lafayette (iron), another sample reported in the literature to have a similarly high Ni content, is probably a pseudometeorite.