Two geostatistical methods for history matching are presented. Both rely on the sequential simulation principle for generating geologically sound realizations. The first method relies on perturbing the sequential simulation through the perturbation of the conditional distribution models; the second method relies on the perturbation of random numbers. We show that both approaches are general in ...

Tropospheric ozone (O3) pollution is a major problem worldwide, including in the United States of America (USA), particularly during the summer months. Ozone oxidative capacity and its impact on human health have attracted the attention of the scientific community. In the USA, sparse spatial observations for O3 may not provide a reliable source of data over a geo-environmental region. Geostatis...

Nitrogen is the most important driving factor in primary production and decomposition arid semi-arid ecosystems. The effects of shrub encroachment on nitrogen cycling have been investigated at site scale but seldomly conducted landscape scale. Here, we selected 43 shrubland sites distributing across 3000 km 2 area temperate desert grassland eastern Yanchi County Ningxia Hui Autonomous. We spati...

Simulated maximum likelihood estimates an analytically intractable likelihood function with an empirical average based on data simulated from a suitable importance sampling distribution. In order to use simulated maximum likelihood in an efficient way, the choice of the importance sampling distribution as well as the mechanism to generate the simulated data are crucial. In this paper we develop...

A new method is proposed for the classification of data in a spatial context, based on the minimization of a variance-like criterion taking into account the spatial correlation structure of the data. Kriging equations satisfying classification bias conditions are then derived for interpolating the rainfall data while taking into account the classification.

First, geostatistics provides descriptive tools such as semivariograms to characterize the spatial pattern of continuous and categorical soil attributes. Various interpolation (kriging) techniques capitalize on the spatial correlation between observations to predict attribute values at unsampled locations using information related to one or several attributes. An important contribution of geost...

We present a numerical study of the scale up problem for the fractional ow function in the Buckley-Leverett equation for ow in porous media. The scale up problem is to deene an averaged equation by local spatial averages, mapping from a micro-physical description to a meso-physical description and from a ne discretization grid to a coarser one. Scale up leads to the closure problem, which is th...