Geopsy: H/V and Spectrum Toolboxes: Time Tab: Time windows

The four sub-tabs of the Time windows section in the Time tab

This section is divided into four tabs:

• General: window selection parameters

• Raw signal: STA/LTA crieria applied to the raw signal

• Filter: filtering criteria for applying STA/LTA on the filtered signal

• Filtered signal: STA/LTA criteria applied to the filtered signal using the filtering criteria defined in the Filter sub-tab

General

The General tab in the Time windows section of the Time tab

This sub-tab contains the criteria used to select stable signal windows:

• Window length
• Window overlap
• Bad sample set-up
• Anti-triggering set-up

MAIN ARTICLE: General tab

Raw signal

This sub-tab is divided into two sections:

• STA/LTA parameters section (to the left)
• Apply to section (to the right)

A box at the bottom indicates whether or not the anti-trigger is applied to the raw signal.

MAIN ARTICLE: Anti-trigger parameters

Filter

Contains the filtering parameters used in the Filtered Signal tab.

MAIN ARTICLE: Filter

Filtered signal

This sub-tab is divided into two sections:

• STA/LTA parameters section (to the left)
• Apply to section (to the right)

A box at the bottom indicates whether or not the anti-trigger is applied to the filtered signal.

MAIN ARTICLE: Anti-trigger parameters

Windowing and data flow sub-section

Two boxes and one pop-up menu located at the bottom of the Time windows section are used to control windowing and real time data acquisition flow.

• Update box: should be checked when using geopsy for real time data acquisition. Checking the box when no data flow is entering has no effect on the processing.

• Common box: check this box to force selecting the same windows on all signal tracks, i.e. STA/LTA threshold must be verified simultaneously on all tracks in order to keep a window. When the box is unchecked, STA/LTA threshold must be verified on each track taken separately. There is no need to check this box in H/V processing, as in this case it is automatically applied.

Resulting windowing with the Common box unchecked

Resulting windowing with the Common box checked

• Select pop-up menu: used to determine which action is undertaken in the windowing process.

When the windowing has not yet been performed with the current parameters, a "*" is displayed besides Select

Select has not been used yet

When the windowing has already been performed with the current parameters, the "*" is no longer displayed besides Select

Select has already been used

The window selection process includes five possible actions.

Options in Select pop-up menu

Auto: windows are selected automatically using the criteria of the General sub-tab of the Time section.

Add: manually add windows. Choose this option and then, with the cursor, select a zone in the signal display where windows have to be added. If an existing window is included in the zone it will not be affected. Note that a window is added only if the criteria of the General sub-tab of the Time section are fulfilled.

Remove: manually remove windows. Choose this option and then, with the cursor, select a zone in the signal display where windows have to the removed.

Inverse: select the windows that were previously not selected. When no windowing has been performed, applying Inverse will select windows all along the signal without applying the windowing criteria.

Clear: automatically remove all windows.

Load: load windows from previous processing stored in a name.log file.

Resulting Auto windowing

Resulting Inverse windowing applied to the above Auto windowing