The excavation hazard is calculated on minodes that represent underground tunnels as a series of connected nodes. For more information on minodes and to find out how to create or update them, go to this page: Minode Generator

This app is all about analysing seismically active faults. There are three ways of ranking seismic faults:

Specialised assessment of seismically active faults and related hazards.

You can pick any grid cell to view the frequency magnitude chart of events found in the local area. This is the b-value used for this grid point. The b-value is a very sensitive parameter in hazard calculations, and there are cases where the automatic FM modelling algorithm may not work well. There are several markers to help identify potential areas where the FM model may not represent the data accurately:

If you pick a minode in the 3D View, the grid point sources that contribute to the hazard at that minode will be plotted, scaled by how much they contribute. Theoretically, every grid point contributes to the hazard at a minode, but there is an accuracy threshold applied with a minimum probability to speed up the calculations. Increasing the accuracy will result in more contributing grid point sources.

Overview

Probabilistic seismic hazard evaluation based on grid and spatial methods.

Estimating seismic hazard for work areas using excavation view analysis.

The hazard assessment app is designed to be simple to use but beneath the interface is a lot of complexity. It is important to be familiar with the underlying calculations and ensure that you are aware of the assumptions and limitations of the analysis. The calculations have been described in the linked pages below.

There are three types of isosurfaces that can be plotted in the Hazard Isosurfaces window. The details behind the calculation of each parameter is linked in the pages below:

Interpreting hazard isosurfaces and spatial distribution of seismic events.

Grid Definition

Mine Geometry Model Minode Generator is a new utility app which enables you to generate your own new minodes from a mine geometry model. If you're not sure what minodes are or why you would want to generate them, see What are minodes? If you're not sure what mine geometry models are, see Mine Geometry Models Application.

How b-value sensitivity affects seismic hazard calculations and event rates.

Quantifying effects of input parameter variations on seismic hazard.

Separating clustered and background seismic events using stochastic methods.

Calculating peak particle velocity from seismic events and ground motion.

You can now plot the relationship in a couple of different ways:

That is the question. An explainer on seismic hazard measurement.

Hazard can be tracked over time by specifying a number of time steps and a step interval. The back analysis tool will step the backdate backward through time and summarise the hazard within each mining volume. Mining volumes can be defined in the Configuration area (link to filter volume editing page). The hazard within each mining volume is calculated by accumulating the hazard within each grid cell or for each minode within the volume.

MUL refers to the truncating magnitude of the Gutenberg-Richter distribution