TY - JOUR A1 - Chen, Yen-Shin A1 - Weatherill, Graeme A1 - Pagani, Marco A1 - Cotton, Fabrice Pierre T1 - A transparent and data-driven global tectonic regionalization model for seismic hazard assessment JF - Geophysical journal international N2 - A key concept that is common to many assumptions inherent within seismic hazard assessment is that of tectonic similarity. This recognizes that certain regions of the globe may display similar geophysical characteristics, such as in the attenuation of seismic waves, the magnitude scaling properties of seismogenic sources or the seismic coupling of the lithosphere. Previous attempts at tectonic regionalization, particularly within a seismic hazard assessment context, have often been based on expert judgements; in most of these cases, the process for delineating tectonic regions is neither reproducible nor consistent from location to location. In this work, the regionalization process is implemented in a scheme that is reproducible, comprehensible from a geophysical rationale, and revisable when new relevant data are published. A spatial classification-scheme is developed based on fuzzy logic, enabling the quantification of concepts that are approximate rather than precise. Using the proposed methodology, we obtain a transparent and data-driven global tectonic regionalization model for seismic hazard applications as well as the subjective probabilities (e.g. degree of being active/degree of being cratonic) that indicate the degree to which a site belongs in a tectonic category. KW - Fuzzy logic KW - Earthquake hazards KW - Seismicity and tectonic Y1 - 2018 U6 - https://doi.org/10.1093/gji/ggy005 SN - 0956-540X SN - 1365-246X VL - 213 IS - 2 SP - 1263 EP - 1280 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Ebert, Thomas A1 - Trauth, Martin H. T1 - Semi-automated detection of annual laminae (varves) in lake sediments using a fuzzy logic algorithm JF - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences N2 - Annual laminae (varves) in lake sediments are typically visually identified, measured and counted, although numerous attempts have been made to automate this process. The reason for the failure of most of these automated algorithms for varve counting is the complexity of the seasonal laminations, typically rich in lateral fades variations and internal heterogeneities. In the manual counting of varves, the investigator acquired and interpreted flexible numbers of complex decision criteria to understand whether a particular simple lamination is a varve or not. Fuzzy systems simulate the flexible decision making process in a computer by introducing a smooth transition between true varve and false varve. In our investigation, we use an adaptive neuro fuzzy inference system (ANFIS) to detect varves on the basis of a digital image of the sediment. The results of the application of the ANFIS to laminated sediments from the Meerfelder Maar (Eifel, Germany) and from a landslide-dammed lake in the Quebrada de Cafayate of Argentina are compared with manual varve counts and possible reasons for the differences are discussed. (C) 2015 Elsevier B.V. All rights reserved. KW - Varve KW - Lake sediment KW - Image processing KW - Fuzzy logic KW - MATLAB KW - Statistics Y1 - 2015 U6 - https://doi.org/10.1016/j.palaeo.2015.05.024 SN - 0031-0182 SN - 1872-616X VL - 435 SP - 272 EP - 282 PB - Elsevier CY - Amsterdam ER -