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Le thuya de Berbérie « Tetraclinis articulata Vahl », espèce résineuse endémique d’Afrique du Nord se trouve généralement sous forme de taillis. La valorisation de la biomasse de thuya, et en particulier de son bois peut être envisagée par la filière papetière par le biais d’une cuisson soude en présence d’anthraquinone (AQ). Le bois jeune de thuya (20 ans) se délignifie bien à l’aide d’une cuisson soude-anthraquinone dans les conditions habituellement appliquées aux résineux avec un temps total de cuisson de 145 min et une température de palier de 165 ◦C. Le rendement brut obtenu est égal à 43,3 % avec un indice Kappa de 33,6. Dans les mêmes conditions de cuisson, le bois âgé (60 ans) peut être lessivé mais se délignifie moins facilement., The coniferous trees of the thuya de Berbérie (Tetraclinis articulata Vahl), from the North Africa (Algeria) is commonly grown as a coppice stand. The biomass of thuya, and especially its wood, can be transformed in pulp by the paper and pulp industry throughout the soda cooking process with the help of the anthraquinone (AQ). The young wood (20 years-old) is well delignified in the soda–anthraquinone process, in the usual conditions applied to the resinous species, in the cooking time schedule of 145 min with the level of 165 ◦C of temperature. The pulp yield of raw material obtained is 43.3% (oven dried wood), with a kappa number of: 33.6. In the same cooking conditions, the mature wood (60 years-old) can be also treated, but with some lower delignification level.

When processing seismic times, it is of upmost importance to take into consideration the action of faulting, to allow both a correct estimation and display of the data. Kriging with a fault throw as an imposed drift allow to include a very precise model of faults to the standard drift functions. After examining in detail an academic example in 1-D,the routine 2-D practical situation is studied and 2 real examples are shown.

Variogram.- Improving the Estimation and Modelling of the Variogram.- Towards Resistant Geostatistics.- Statistical Inference of the Semivariogram and the Quadratic Model.- Use of the Jackknife Method to Estimate Autocorrelation Functions (or Variograms).- Computing Variograms in Folded Strata-Controlled Deposits.- The Variogram and Kriging: Robust and Resistant Estimators.- The Variogram and its Estimation.- Inference for Spatial Autocorrelation Functions.- Precision of Global Estimation.- Precision of Estimation of Recoverable Reserves: The Notion of Conditional Estimation Variance.- Estimation Variance of Global Recoverable Reserve Estimates.- Combining Local Kriging Variances for Short-Term Mine Planning.- Application of a Geostatistical Method to Quantitatively Define Various Categories of Resources.- Kriging.- Conditional Bias in Kriging and a Suggested Correction.- Positive Kriging.- Correcting Conditional Bias.- mAD and Conditional Quantile Estimators.- Kriging Seismic Data in Presence of Faults.- Co-Kriging - New Developments.- Indicator Kriging.- The Place of Non-Parametric Geostatistics.- Indicator Kriging as Applied to an Alluvial Gold Deposit.- Estimating Local Recoverable Reserves Via Indicator Kriging.- Conditional Recovery Estimation Through Probability Kriging - Theory and Practice.- Recoverable Reserves.- Recovery Estimation: A Review of Models and Methods.- The Selectivity of the Distributions and "The Second Principle of Geostatistics".- Local Estimation of the Recoverable Reserves: Comparing Various Methods with the Reality on a Porphyry Copper Deposit.- Isofactorial Models and Change of Support.- Geostatistical Application in Tabular Style Lead-Zinc Ore at Pine Point Canada.- Local Estimation of the Block Recovery Functions.- The Block Distribution Given a Point Multivariate Normal Distribution.- Spectral Analysis and Data Analysis.- Three-Dimensional, Frequency-Domain Simulations of Geological Variables.- Factorial Kriging Analysis: A Substitute to Spectral Analysis of Magnetic Data.- The Factorial Kriging Analysis of Regionalized Data. Its Application to Geochemical Prospecting.- The Analysis of Second-Order Stationary Processes: Time Series Analysis, Spectral Analysis, Harmonic Analysis, and Geostatistics.

This paper is a review of the “State of the Art” in recovery estimation, from the theoretical and practical point of view. After a recall on early methods, some of them being still usefull, the main methods currently employed are compared in the case of point recovery: namely indicator kriging, disjunctive kriging, conditional distribution. The pratice of each method is reviewed then in the important case of block recovery, including a comparison of the change-of-support methods involved.