Applet ( in separate window, ca. 450 x 480 Pixel )
( Background :
see
Seismometer Documentaion
and
Seismometer-Galvanometer Documentation,
see also Applet
Response Functions of Seismographs,
in separate windows )
- HowTo -
Dialogue Window :
( Screenshot )
COMPARE SEISMOGRAPH SYSTEM : WIECHERT_Z...
alows to select up to 3 of the seismograph systems implemented :
- WIECHERT_H, WIECHERT_Z and WOOD-ANDERSON
- are historical seismometers with "direct" recording,
- characterized by natural period, damping and a static amplification ( = recorded amplitude / mass excursion ).
- WWSSN_SP / LP, BENIOFF_LP, GALITZIN, KIRNOS and DEMO_SP / LP
- are seismometer - galvanometer systems, where
- a velocity transducer ( coil-magnet-assemly ) of a seismometer is connected to the coil of a galvanometer via a resistive T element,
- i.e. two resistances in series with seismometer / galvanometer coil and one shunt resistance.
- ( see Seismometer-Galvanometer Documentation
and Applet Seismometer-Galvanometer Coupling )
- The geophones SM4_10Hz and L4_2Hz
- are moving coil instruments connected to a digital recording system StrataView.
- The seismometer STS_2 ( Wielandt - Streckeisen )
- is a force-balance broadband seismometer.
- ( see Seismic Sensors and their Calibration, E. Wieland,
- in New Manual of Observatory Practice.
- Details see Applet Response Functions of Seismographs.
The graphic display is controlled by the display dialogue ( background light blue ) :
- XFR ( F ) / XFR ( Z ) / F + Z
- shows the frequency response and/or the corresponding Z-transform
- ( AMPL = ampltude, PHAS = phase in separate windows )
- for the seismograph systems selected.
- HIDE RESP WIN ...
- hides / shows the output signals in the time domain for different ground motions :
- DELTA IMP ( = Dirac impulse ),
- UNIT STEP,
- KUEPPERS_2 ( = Kueppers signal, order 2 ),
- or
- K_2 x HANNING ( = as above, with Hanning taper ),
- or
- one of the four earthquake recordings implemented.
- ( 200 SMP...10 SMP refers to Kueppers signals only and allows to select the signal length and, together with F-SAMP, the predominant frequency of the signal,
- SCL x 1.0...x 100 refers to the graphic display of the ground displacement of the earthquake examples. )
Top of Page HowTo Screenshots Download
- Screenshots -
Seismographs : WOOD-AND., WWSSN_LP and KIRNOS,
response to ground displacement
( param. see below : screenshot Text Area )
Colors : magenta = WOOD-AND., cyan = WWSSN_LP, blue = KIRNOS.
XFR ( F )
Amplitude ( AMPL ) and phase ( PHAS ) of
frequency response
XFR ( Z )
Amplitude ( AMP ) of Z-Transform
( F-SAMP 80 [Hz], +LOWPASS )
Resp. to UNIT STEP
( XFR ( Z ) as above, red = input signal =
ground displacement )
Earthquake recording HALLE
( F-SAMP 80 [Hz], +LOWPASS,
red = ground displacement )
Earthquake recording TURKEY
( F-SAMP 20 [Hz], +LOWPASS,
red = ground displacement )
LIST SEIS :
Top of Page HowTo Screenshots Download
Class and html files for a local installation of the applet are available as a zip file and as a tar.gz file.
More applets at : Geophysics Department TU Clausthal
Rev. 12-nov-2012
Comments to
Fritz Keller
( ned gschempfd isch globd gnueg )