Application of statistical methods to evaluation of mineral deposits

Only in recent years have statistical methods been applied to evaluation of ore reserves. An attempt is made in this study to prepare an outline to be followed throughout the exploration in order that statistical methods can be applied to valuation problems. Particular emphasis is given to the preliminary requirements to a statistical approach. Representative parameters, sampling pattern, and sample size are discussed in separate chapters --Abstract, page iii

Paul Ramdohr (1890-1985)

Saupé Francis. Paul Ramdohr (1890-1985). In: Bulletin de Minéralogie, volume 108, 6, 1985. p. 735

Avant-Propos. Concentrations métalliques et milieux confinés.Metal concentrations and restricted environments

Saupé Francis. Avant-Propos. Concentrations métalliques et milieux confinés.Metal concentrations and restricted environments . In: Sciences Géologiques. Bulletin, tome 39, n°3, 1986. Concentrations métalliques et milieux confinés. pp. 211-214

Avant-Propos. Concentrations métalliques et milieux confinés.Metal concentrations and restricted environments

Saupé Francis. Avant-Propos. Concentrations métalliques et milieux confinés.Metal concentrations and restricted environments . In: Sciences Géologiques. Bulletin, tome 39, n°3, 1986. Concentrations métalliques et milieux confinés. pp. 211-214

Single mineralizing episodes in the epigenetic mercury ore deposits of Almadén: Isotopic evidence from the Las Cuevas deposit

Nine new S isotope analyses are presented of which 8 are from the Las Cuevas deposit. They are compared with data from literature. The different deposits of the district (and the three orebodies of the Almadén deposit) are characterised by a specific range of a34S value

A Possible Source of Error in 14C Dates: Volcanic Emanations (Examples from the Monte Amiata District, Provinces of Grosseto and Sienna, Italy)

Wood from regular timbering of a shallow seated mine in Tuscany gave 14C ages of 5730 +/- 100 years BP, much too old to be attributed to one of the known civilizations of Italy. This mine is located in a region of declining volcanic activity, noticeable especially through numerous emanations (natural or incidentally induced by drillings). It was suspected that the analyzed wood had grown in an environment where the normal atmosphere had been diluted by volcanic emanations. To check this hypothesis, living plants (trees, bushes and reeds) and volcanic emanations have been sampled and their 14C content measured. All present day plants are depleted in 14C, giving a fictitious age different from 0 (1805, 1820, 2540, 4350 years BP). Of the gaseous emanations sampled, two have a high pressure and show virtually no 14C (>41,000 years BP). Two others have a pressure close to atmospheric, and small amounts of 14C were introduced by atmospheric contamination (22,570 and 30,580 years BP). Conclusion: plants grown in the vicinity of volcanic emanations have 14C activities that are too low because of a natural 14C dilution and yield anomalously high ages. The delta-13C values obtained for two of these plants (-27.4 per mil and -23.7 per mil) are close to the average for plants in general (-25 per mil), whereas the CO2 of mofettes is heavier than atmospheric CO2.This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Datation par les méthodes K/Ar et Rb/Sr de quelques roches de la partie orientale de l'Ile d'Elbe (Province de Livourne, Italie)

Radiometric dating of the Quartz-monzonite of Porto Azzurro (Elba Island, Italy) gave ages of 5.9 ± 0.5 M.y. (K/Ar) and of 5.1 M.y. (Rb/Sr). Similar K/Ar ages were obtained for the biotite (6.2 ± 0.5 M.y.) and the K-feldspar (5.4 ± 1.1 M.y.) from one sample of this rock. The quartz-monzonite intrusion produced a hydrothermal metamorphism (amphibolite at 6.6 ± 0.9 — KAr) and a contact metamorphism. The later is deduced from K/Ar ages of the « Scisti di Calamita » (5.1 ± 0.6 M.y.) and of three aplite-swarms giving respectively 5.2 ± 0.7, 5.7 ± 0.4 and 6.1 ± 1.1 M.y.Des datations nouvelles de la quartz˗monzonite de Porto-Azzurro (Ile d'Elbe, Italie) ont donné des âges de 5,9 ± 0,5 M.a. (K/Ar) et de 5,1 M.a. (Rb/Sr), concordants avec les âges K/Ar obtenus sur la biotite (6,2 ± 0,5 M.a.) et le feldspath potassique (5,4 ± 1,1 M.a.) d'un échantillon de cette roche. L'intrusion de quartz˗monzonite a été accompagnée d'un métamorphisme hydrothermal (amphibolite hydrothermale : 6,6 ± 0,9 M.a. — K/Ar) et d'un métamorphisme thermique donné par les âges K/Ar des Schistes de Calamita (5,1 ± 0,6 M.a.) et de trois essaims d'aplites (5,2 ± 0,7 ; 5,7 ± 0,4 et 6,1 ± 1,1 M.a. respectivement).Saupé Francis, Marignac Christian, Moine Bernard, Sonet Jacques, Zimmermann Jean-Louis. Datation par les méthodes K/Ar et Rb/Sr de quelques roches de la partie orientale de l'Ile d'Elbe (Province de Livourne, Italie). In: Bulletin de Minéralogie, volume 105, 3, 1982. pp. 236-245