ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00104.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The Goldstein‐Short graph for the determination of ironmeteorite cooling rates from kamacite bandwidths andNiconcentrations has been approximated by the equation:log CR = −2.040 log BW — 8.940 log Ni + 8.700where the cooling rate, CR, is in units of°K/m.y., the bandwidth, BW, in units of mm, andNiconcentration is in weight percent. The equation reproduces the Goldstein‐Short values to within ±7% within theNiconcentration range 7 to 14%, which includes most octahedrites. The discrepancy between the graphical or analytical cooling‐rate estimations and those estimated from microprobe data is a factor o

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00105.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The earlier efforts to approximate the total number and mass of fragments from Pułtusk meteorite shower 1868 have been found unsatisfactoryWith the use of the field data of Samsonowicz and the sorting equation after Frost, differential expressions approximating the mass and number of fragments are derived. These expressions numerically integrated over the elliptical strewnfield area lead to the estimates ∼ 1.8 times 105and ∼ 2 times 106g for the total number and mass of fragments respectively.The meaning of the obtained results is discu

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00106.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The Raco meteorite fell in Raco, a small village in the Province of Tucumán, Argentina, on November 17, 1957. In the Centro de Pesquisas Geocronologicas of the University of Sao Paulo (Brazil), the authors determined itsK‐Arage: 4.400±28

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00107.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00108.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00109.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

We have classified 1858 lithic and vitreous fragments from the Luna 16 core‐tube sample. They were taken from the soil fractions ranging in size from 150 to 425 μ, at levels A and G (γ). 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. Luna 16 basalts are texturally and mineralogically similar to Apollo 11 basalts, though the former are characterized by more Fe‐rich olivines and pyroxenes and by lower ilmenite contents than are Apollo 11 basalts. The atomic ratio Al/Ti in Luna 16 basalt pyroxenes in about 1.5; Apollo 11 basalt pyroxenes have Al/Ti = 2.0, indicating the possibility of a lower mean valence for Ti in the Luna 16 material than in the Apollo 11 material. Most light‐colored lithic fragments are anorthositic rather than noritic in character and are comparable to Apollo 11 anorthosites in mineral chemistry. We believe they are samples of terra regions to the north of the Luna 16 landing site. Triangular diagrams plotting normative plagioclase, normative mafics plus oxides, and normative orthoclase plus apatite neatly separate the three major types of lunar materials — mare basalts, anorthosites, and noritic rocks — and reveal that the Luna 16 regolith is composed of mare basalt and anorthosite, with very little norite component. Colorless‐to‐greenish glass occurs in the Luna 16 sample, which has high Fe and low Ti; it may represent gabbroic rock related to

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00110.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00111.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The temperature gradient induced in the Lost City meteorite during its nine‐second flight through the atmosphere has been determined from measurements of the variations in the natural TL output of the meteorite with depth below the surface of the specimen. The rate of temperature change decreases about 5 °C per mm in the range of 4 mm to 15 mm below its surface. Although temperatures above 205 °C penetrated only the outer 4 mm of the meteorite, temperatures higher than 120 °C penetrated as far as 20 mm below its sur

ISSN:0026-1114    

DOI:10.1111/j.1945-5100.1971.tb00112.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY