6th Intercontinental Geoinformation Days (IGD), Baku, Azerbaijan, 13 - 14 June 2023, vol.6, pp.207-210
Block
modeling is a frequently employed technique to yield the block motions such as
block rotations and internal strains as well as to estimate fault slip rates via GNSS
velocity data. The accuracy of the modeling outcomes heavily relies on the precise determination
of the block boundaries. Typically, surface traces of mapped faults, seismological data,
and/or GNSS velocity fields are utilized for this purpose. Nonetheless, the identification
of suitable and accurate block boundaries for the velocity field is subject to interpretation
and subjectivity. One method that can be used to determine block boundaries is the clustering
method. Clustering analysis assigns data to similar groups based on similarities and
differences in the data subject to clustering. Since the 2000s, this method has been used in the
clustering of GNSS velocities and helps to determine block boundaries before
block modeling. In this study, we utilized the Non-negative Matrix Factorization (NMF) method to cluster the current GNSS horizontal velocity field of Türkiye, and we compared the results with the
literature. First, we clustered velocities from k = 2 to 9 using five distinct single clustering
methods to determine the block boundaries. Then, we used the optimum number k = 5 to cluster the
data using NMF-based ensemble clustering.