Topological analysis in Monte Carlo simulation for uncertainty propagation
Topological analysis in Monte Carlo simulation for uncertainty propagation
复制标题
不确定性传播蒙特卡罗模拟中的拓扑分析
DOI:
10.5194/se-10-1663-2019
复制
发表时间:
2019
期刊:
影响因子:
3.4
通讯作者:
V. Ogarko
中科院分区:
文献类型:
--
作者:
Evren Pakyuz;M. Jessell;J. Giraud;M. Lindsay;V. Ogarko
Abstract. This paper proposes and demonstrates improvements for the
Monte Carlo simulation for uncertainty propagation (MCUP) method. MCUP is a
type of Bayesian Monte Carlo method aimed at input data uncertainty
propagation in implicit 3-D geological modeling. In the Monte Carlo process,
a series of statistically plausible models is built from the input dataset
of which uncertainty is to be propagated to a final probabilistic geological
model or uncertainty index model. Significant differences in terms of topology are observed in the plausible
model suite that is generated as an intermediary step in MCUP. These
differences are interpreted as analogous to population heterogeneity. The
source of this heterogeneity is traced to be the non-linear relationship
between plausible datasets' variability and plausible model's variability.
Non-linearity is shown to mainly arise from the effect of the geometrical
rule set on model building which transforms lithological continuous
interfaces into discontinuous piecewise ones. Plausible model heterogeneity
induces topological heterogeneity and challenges the underlying assumption
of homogeneity which global uncertainty estimates rely on. To address this
issue, a method for topological analysis applied to the plausible model
suite in MCUP is introduced. Boolean topological signatures recording
lithological unit adjacency are used as n-dimensional points to be
considered individually or clustered using the density-based spatial
clustering of applications with noise (DBSCAN) algorithm. The proposed
method is tested on two challenging synthetic examples with varying levels
of confidence in the structural input data. Results indicate that topological signatures constitute a powerful
discriminant to address plausible model heterogeneity. Basic topological
signatures appear to be a reliable indicator of the structural behavior of
the plausible models and provide useful geological insights. Moreover,
ignoring heterogeneity was found to be detrimental to the accuracy and
relevance of the probabilistic geological models and uncertainty index
models.
Highlights.
Monte Carlo uncertainty propagation (MCUP) methods often produce
topologically distinct plausible models. Plausible models can be differentiated using topological signatures. Topologically similar probabilistic geological models may be obtained
through topological signature clustering.