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FAQ

How do I create and assess a user defined trigger in Short Term Response Analysis?

Open the Simple Response Viewer window in the app then to create a User Trigger:

  1. Click "Control Panels"

  2. Click "User Triggers"

  3. The "User Triggers" panel will then open on the left

  4. Input the location and date of your trigger

  5. Save the trigger

Using the trigger for analysis: 6. Click "Tables"

  1. Click "User Triggers"

  2. The User Trigger Table View will appear

  3. Select your saved trigger

Why is there no cumulative energy line?

The shape of the cumulative energy graph inherently has no diagnostic value and is often misleading. The accumulation of a logarithmic parameter is dominated by the largest events and results in a curve with a somewhat arbitrary, random shape which doesn’t represent the underlying stochastic process. The total energy released has some value and is included in the blast triggers table.

To illustrate further, the video below shows a repeated generation of synthetic seismic data where each sample has the same number of events, the same b-value, and the same Omori relationship.

Why isn't it called Omori Analysis anymore?

Omori Analysis has been a bit of a misnomer in the mining industry. The Omori Law (and Modified Omori Law, MOL) is a mathematical relationship to describe the activity rate of aftershocks over time. There isn't really such a thing as 'Omori Analysis' or an 'Omori Chart'. What most people call an 'Omori Chart' is simply a cumulative events chart. Why make it more complicated than that!

What are the 'nearby' events?

Nearby events are shown in the Response 3D view and the Magnitude-Time chart to indicate events that are close, but just outside, the response time and radius. Events are 'nearby' if they occur: Less than 0.25 × time before the trigger, less than 2.0 × time after the trigger, and less than 2.0 × radius from the trigger.

How seismic events are associated with a trigger blast if included in multiple blast responses?

If you tick a blast, all the events within the radius and time indicated in the Response Controls panel will show (in 3D, in the chart, and the stats of these events in the table as well).

If you tick multiple blasts (either if they are close or not), all events within their respective time / space will also show.

There is an option to ‘include duplicate events’ or not. If you hover over this option, it will tell you the details you want:

  • When Include duplicates events ON : The same event may be included in multiple responses
  • When Include duplicates events OFF : Duplicate events will be removed, trigger that is the most recent is assigned first, then the closest.

Example: Two near (time & space) blasts ticked​

Duplicate Events Include: Unticked

  • Both occurred close in time and space The ‘Max ML’ indicated in the table for both is the same, because that ML=1.75 event is included in both of their response.
  • The “Response Events charts” have maximum or 2500 and 7000 (y-axes).

Duplicate Events Include: Ticked If the include duplicate is ticked, the maximum y-axes double.