摘要:

With the recent extension of K‐Ar dating methods within the Upper Pleistocene time, the use of new standards is recommended to allow calibration and inter‐laboratory comparisons. For this purpose, two pure microlitic groundmass reference materials were prepared from trachy‐basaltic lavas: Trachyte (MDO‐G) from Mont Dore, Puy de Sancy, Massif Central is around 250 000 years old; the second Trachyte (ISH‐G) from the Isle of Ischia, Gulf of Naples (Italy), is historical: Arso flow erupted on Christmas 1301 ‐ Janu

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1992.tb00487.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

More than 40 trace elements in 11 Chinese geological reference materials (stream sediments) GSD‐1 to GSD‐7 and GSD‐9 to GSD‐12 were determined by inductively coupled plasma‐mass spectrometry (ICP‐MS). Open acid digestions were used to prepare samples for the determination of most elements. However, for the measurement of Y, Zr and Hf, it was found necessary to use an alkali fusion in order to make fully quantitative measurements. The results obtained in this work are generally in good agreement with the recommended values from the sub‐ppm level to>several hundred ppm and illustrate the versatility of the technique, particularly for some less well character

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1992.tb00488.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

New analyses for AU, Ir, Pd and Pt in the USGS rock standard PCC‐1, carried out by two different radiochemical neutron activation procedures, are compared with similar analyses of a spinifex‐textured komatiitic peridotite. Better precision obtained for most of these elements on the komatiitic peridotite, in conjunction with consideration of literature values for PCC‐1, suggest that the volcanic peridotite is characterized by a more homogeneous distribution of noble metals than PCC‐1, a plutonic peridotite. These results suggest that reference materials for the analysis of sulfur‐poor mafic and ultramafie rocks with background levels of noble metals will be more satisfactory if volcanic rocks are

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1992.tb00489.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Two chromitite samples from the Isles of Shetland (North Scotland) have been processed, each in 200 kg quantities, as reference samples for the determination of gold and the platinum‐group elements (PGE). One of these samples, Chromitite CHR‐Pt+is enriched in the PGE and the other, Chromitite CHR‐Bkg has much lower concentrations. A detailed assessment of sample homogeneity is presented, together with the results of a cooperative study by thirty‐five international geochemical laboratories, private and public. Contributed data together with derived working values are presented for Au and the PGE as well as for major, minor and a few trace elements. It is hoped that this first compilation report will encourage additional laboratories to participate in further studies of the PGE in these two CHR

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1992.tb00490.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1992.tb00491.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY