Difference between revisions of "H/V spectral ratio"

From GeopsyWiki
Jump to navigation Jump to search
Line 11: Line 11:
 
== Window selection ==
 
== Window selection ==
  
[[Image:HV_toolbox_time.png|thumb|right|200px|Timing tab in toolbox]]
+
[[Image:HV_toolbox_time.png|thumb|right|200px|General sub-tab in Time tab of toolbox]]
* Make sure you are in the [[Geopsy: Toolbox_time_tab|Time tab]], and that parameters are as in the example window.
+
* Make sure you are in the [[Geopsy: Toolbox_time_general_tab|Time tab]], and that parameters are as in the example window.
 
<br style="clear: both"/>
 
<br style="clear: both"/>
  
[[Image:HV_toolbox_time_sta.png|thumb|right|200px|Timing tab in toolbox]]
+
[[Image:HV_toolbox_time_sta.png|thumb|right|200px|Raw signal sub-tab in Time  tab oftoolbox with anti-trigger parameters]]
* Click on the [[Geopsy: Toolbox_anti_trigger_tab|Raw signal]], to check that anti-trigger parameters are as in the example window.
+
* Click on the [[Geopsy: Toolbox_time_rawsignal_tab|Raw signal]], to check that anti-trigger parameters are as in the example window.
 
<br style="clear: both"/>
 
<br style="clear: both"/>
  

Revision as of 08:24, 9 March 2010


This tool is used to obtain Horizontal to Vertical (H/V) spectral ratios from any type of vibration signals (ambient vibrations, earthquake…). The example used for explanations is an ambient vibration recording.

Getting ready

Window selection

General sub-tab in Time tab of toolbox
  • Make sure you are in the Time tab, and that parameters are as in the example window.


Raw signal sub-tab in Time tab oftoolbox with anti-trigger parameters
  • Click on the Raw signal, to check that anti-trigger parameters are as in the example window.


Select pop-up menu
  • Click on the Select button and select Auto.


Number of selected windows
  • The number of selected windows appears at the bottom right corner of the time tab.

The number of windows should be as in the example.

Selected windows
  • Selected windows should appear as green rectangles on the signal viewer.


Processing parameters

Processing tab in toolbox
  • Click on the Processing tab, and make sure that parameters are as in the example window.


Output parameters

Output tab in toolbox
  • Make sure you are in the Output tab, and that parameters are as in the example window.


Data processing

  • Click on Start button at the bottom of the toolbox, whatever tab is displayed. HV toolbox star.png


No selected windows pop-up window
  • In case no window selection has been performed, a pup-up window appears.

Simply click on the Yes button and processing will follow its way.

Results

Signal diplay

Signal diplay with colored windows used for computing H/V matching with colours of individual H/V curves presented below
  • Selected windows are colored, matching colours in he H/V graphics, i.e. colour of individual H/V curves have the same colour as the signal windows.


H/V curve

Timing tab in toolbox
  • The blak curve represents H/V averaged over all colored individual H/V curves The two dashed lines represent H/V standard deviation.
  • The grey area represent the peak frequency and its standard deviation. The frequency value is at the limit between the dark and clear areas.


Peak frequency and standard deviation values

* Use the cursor to get values on the H/V curve. The exact value of the H/V peak frequency and its standard deviation may be obtained by sliding the cursor onto the H/V curve title (Strong_peak) in the upper right corner above the graphics.



The toolbox may be opened in two different ways:

  • if the signal window is already open clik on the H/V icon HV icon.png
  • if the signal window is not open drag the file(s) from the file manager to the H/V icon HV icon.png


The toolbox shows up in the form it was previously closed, with the file name(s) in the header.

The toolbox contains set ups for windowing selection and processing, together with output parameters.


Comprises three tabs: HV toolbox tabs 1.png


Time tab

Divided into three parts

Global time range

Global time range

Used to select all or part of the signal to be processed.

Works like the Waveform/Cut basic signal processing under the Waveform menu.

When "Use only the properties of the first signal" is checked, all tracks use the time parameters (T0, End, Picks) of the top track.


Time windows

Time window paramaters of H/V toolbox

Comprises 4 tabs: HV toolbox tabs 2.png

Windowing results

Below Time windows a line gives the resulting selected windows, in all stations, with possibility to get the number of windows in each station through the View pop-up menu.

HV toolbox other time.png

Saving results

Further readings