Multiple-point geostatistical simulation using the bunch-pasting direct sampling method

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ABSTRACT 13 Multiple-point geostatistics has opened a new field of methodologies by which complex 14 geological phenomena have been modeled efficiently. In this study, a modified form of 15 Direct Sampling (DS) method is introduced which not only keeps the strength of DS 16 simulation technique but also speeds it up by one or two orders of magnitude. While previous 17 methods are based on pasting only one point at a time, here the simulation is done by pasting 18 a bunch of nodes at a time, effectively combining the flexibility of DS with the 19 computational advantages of patch-based methods. This bears the potential of significantly 20 speeding up the DS method. The proposed simulation method can be used with unilateral or 21 1 ‐This is the present address and exposed to change in future. 2 random simulation paths. No overlap occurs in the simulation procedure because the bunch 22 takes the shape of the empty space around the simulated nodes. Systematic tests are carried 23 on different training images including both categorical and continuous variables, showing 24 that the realizations preserve the patterns existent in the training image. To illustrate the 25 method, a Matlab implementation of the method is attached to the paper.