Fractures in the Niagara Escarpment in Ontario, Canada: distribution, connectivity, and geohazard implications

Abstract The Niagara Escarpment is a geological feature located in southern Ontario, Canada, and the northeastern United States, comprising highly fractured sandstone, shale carbonates deposited during Ordovician Silurian periods. Differential erosion of strata has generated steep cliff face which bisects city Hamilton, Ontario. Geological fractures are widespread escarpment result formation unstable blocks rock subject to through rockfall. This presents structural stability issues concern due proximity urban infrastructure. We quantify analyse fracture networks using combined field- numerical-modelling-based approach. location, orientation aperture were documented from local outcrops scanline area survey methods. Clusters poles describing discontinuities identified spherical projections, defining three sets: (1) sub-vertical stratabound set striking N–S, (2) E–W, (3) parallel horizontal sedimentary bedding planes we infer controlled geometry. Discrete network modelling sets highlights their high degree connectivity, contribution geohazards, quantifies role controlling fluid flow strata, dependent on aperture. Additionally, have potential act as free surfaces, facilitating stress conditions approximately cuboid produced, increasing risk rockfalls. conclude that present first-order control fluid-flow properties Escarpment.