Andy Heath - Binder

Binder

The Binder processes a list of phase arrival times (picks) and attempts to associate together groups of picks (P & S) generated by unique seismic events. Multiple events can be generated simultaneously.

Detection of new events:

A regular orthorhombic lattice is constructed beneath the network of stations. Travel times from a node at the centre of each lattice cell are calculated to each station. The new phase arrival (pick) is migrated backwards by calculating the origin time of the pick at each node. The origin times of picks are stored at each node. Each node is inspected in turn and if sufficient origin times fall within a given range a new event is declared. The event is then initially relocated using hypo71.

Once an event has been declared, subsequent picks are first tested to see if they can be associated with the existing event. A set of user-defined parameters determines if an arrival (P or S) can be considered to belong to an event. When no further arrivals can be associated with a particular event it is relocated one last time using the NonLinLoc algorithm.

The Binder software has been used extensively, but it was initially tested against the ANCORP dataset (Northern Chile and Southern Bolivia) and a dataset collected from a dense array in Sumatra. The figures below show the Binder results using these two datasets.