Original paper
Geostatistical modelling of the subsurface geological-geotechnical heterogeneities in the Tabriz Subway, East Azarbayjan Province, Iran
Mahmoudi, Mitra; Khojasteh, Enayatollah Ranjineh; Sharghi, Yousef
Zeitschrift der Deutschen Gesellschaft für Geowissenschaften Band 170 Heft 2 (2019), p. 145 - 159
24 references
published: Dec 9, 2019
published online: Oct 29, 2019
manuscript accepted: Sep 5, 2019
manuscript revision received: Sep 3, 2019
manuscript revision requested: Jul 29, 2019
manuscript received: Jun 18, 2019
ArtNo. ESP171017002002, Price: 29.00 €
Abstract
This study was aimed at evaluating the capabilities of geostatistical methods in constructing a two-dimensional subsurface geological model of soil categories (with a geotechnical insight) along a part of the Tabriz subway (metro) line 2, East Azarbayjan Province in Iran, using three geostatistical methods. One of the important features about the geostatistical predictions, besides their accuracy and reasonability, is the evaluation of uncertainty for the produced models for supporting decision making about the coming steps e.g. in construction and maintenance of tunnels. Indicator Kriging (IK) besides the Sequential Indicator Simulation (SIS) and Generalized Coupled Markov Chain (GCMC) techniques were applied in this study to predict the geological categories at unknown locations. The used dataset came from 11 boreholes and wells along a part of this metro line. First, indicator variables of each soil category were assigned to sampling points along the boreholes. These indicators were then used to model the spatial variability structure of the categories using the indicator variograms and transition probabilities. These models were then used to predict the geotechnical categories at unsampled locations and the model spatial uncertainty. Finally, the reproduction of the indicator variograms and proportions as well as the geological plausibility of the outcomes were assessed.
Keywords
geostatistics • Indicator Kriging (IK) • Sequential Indicator Simulation (SIS) • Generalized Coupled Markov Chain (GCMC) • Tabriz subway • stratigraphic coordinates system