Three BB and SM seismic stations in the Corinth Gulf jointly operated by the universities in Prague ...
Download
1 / 41

Jiri Zahradnik Charles University, Prague - PowerPoint PPT Presentation


  • 68 Views
  • Uploaded on

Three BB and SM seismic stations in the Corinth Gulf jointly operated by the universities in Prague and Patras. Jiri Zahradnik Charles University, Prague. Co-operation:. G-A. Tselentis, E. Sokos, A. Serpetsidaki V. Plicka, J. Jansky. Sergoula, Mamousia, University. CMG 3T BB vel

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Jiri Zahradnik Charles University, Prague' - mavis


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Three BB and SM seismic stations in the Corinth Gulf jointly operated by the universities in Prague and Patras

Jiri Zahradnik

Charles University, Prague


Co operation

Co-operation: operated by the universities in Prague and Patras

G-A. Tselentis, E. Sokos,

A. Serpetsidaki

V. Plicka, J. Jansky


Sergoula mamousia university
Sergoula, Mamousia, University operated by the universities in Prague and Patras

  • CMG 3T BB vel

  • CMG 5T SM acc

  • DM24 + SAM

  • 20 Hz continuous

  • 100 Hz triggered

  • stand-alone

  • 3-5 months


Sergoula mamousia university1
Sergoula, Mamousia, University operated by the universities in Prague and Patras

  • CMG 3T BB vel

  • CMG 5T SM acc

  • DM24 + SAM

  • 20 Hz continuous

  • 100 Hz triggered

  • stand-alone

  • 3-5 months


April 8 2001 serg black obs red synth
April 8, 2001 operated by the universities in Prague and PatrasSERGblack=obs.red=synth.

My “normal” job

is modeling, but

today I want to

discuss the data

reliability.


Are our data accurate
Are our data accurate ? operated by the universities in Prague and Patras

  • Compare the instrumentally corrected records, sampling 100 Hz (5T accel. and the differentiated 3T)

  • Demonstrate complications

Zeros and poles from

factory calibration tests

acceleration

velocity


Vartholomio earthquake
Vartholomio earthquake operated by the universities in Prague and Patras

  • Dec.2, 2002

  • 04:58

  • M=5.4 (PATNET)

  • Mw=5.6 (MEDNET)


Vartholomio dec 2 2002 m 5 4 at mamo 94 km
Vartholomio operated by the universities in Prague and PatrasDec. 2, 2002 M 5.4at MAMO(94 km)


3T clipped operated by the universities in Prague and Patras

(2 mm/sec)


ZOOM operated by the universities in Prague and Patras

3T clipped

(2 mm/sec)


MAMO operated by the universities in Prague and Patras

clipped 3T viewed as non-clipped acceleration

(suggesting a method how to correct clipping)


MAMO operated by the universities in Prague and Patras

with the clipped part

without


Noise natural and instrumental
Noise (natural and instrumental) operated by the universities in Prague and Patras

microseisms resolved by 3T, but not resolved by 5T


MAMO operated by the universities in Prague and Patras

Minimum frequency available from the 5T accelerograph (M 5.4; 94 km)


Vartholomio earthquake m 5 4 at serg 102 km
Vartholomio earthquake operated by the universities in Prague and PatrasM 5.4 at SERG (102 km)


Vartholomio earthquake m 5 4 at serg 102 km1
Vartholomio earthquake operated by the universities in Prague and PatrasM 5.4at SERG (102 km)

temporary

GPS (digitizer)

problem


SERG operated by the universities in Prague and Patras

fit in EW as

good as in Z

(3T || 5T)

some HF noise ?


SERG operated by the universities in Prague and Patras

velocity

not clipped

velocity in SERG is lower than in MAMO,

but acceleration is SERG is higher


SERG operated by the universities in Prague and Patras

ZOOM

a significant HF ‘ringing’ of 3T

(not caused by clipping)


SERG operated by the universities in Prague and Patras


SERG operated by the universities in Prague and Patras


Local event recorded at serg
Local event recorded at SERG operated by the universities in Prague and Patras

  • Dec.10, 2002

  • 16:47

  • M 3.8

  • SERG:

    D=13 km

    A=84o


Local m 3 8 at serg 13 km
Local M 3.8 operated by the universities in Prague and Patrasat SERG(13 km)


Local m 3 8 at serg 13 km1
Local M 3.8 operated by the universities in Prague and Patras at SERG(13 km)

less problems on

the Z-comp. of 3T,

both in HF and LF


Too noisy lf signal on 5t even at f 0 1 hz
Too noisy LF signal on 5T operated by the universities in Prague and Patras even at f ~ 0.1 Hz

M 3.8 recorded at D=13 km


Local event recorded at serg1
Local event recorded at SERG operated by the universities in Prague and Patras

  • Nov. 13, 2002

  • 21:55

  • M 3.0

  • SERG:

    D=7.5 km

    A=51o


SERG operated by the universities in Prague and Patras

November 13, 2002; at 21:55; M 3

SERG: D=7.5 km, A=51o

a rare disturbance

(signal-generated)

NS-comp. of 3T velocity

EW-comp. of 3T velocity


occasionally operated by the universities in Prague and Patras,

the LF signal on 3T is “as bad” as on 5T !


LF operated by the universities in Prague and Patras

the LF signal

on Z-comp.

of 3T is OK


M 3 at serg 7 km
M 3 operated by the universities in Prague and Patras at SERG(7 km)

HF noise on horizontal

components of 3T


Local event recorded at univ
Local event recorded at UNIV operated by the universities in Prague and Patras

  • Nov. 26, 2002

  • 12:13

  • M 3.5

  • UNIV:

  • D=13 km

  • A=209o


Nov 26 2002 m 3 5 at univ 13 km
Nov. 26, 2002 operated by the universities in Prague and PatrasM 3.5 at UNIV(13 km)


Nov 26 2002 m 3 5 at univ 13 km1
Nov. 26, 2002 operated by the universities in Prague and PatrasM 3.5 at UNIV(13 km)

GPS problem


Local event recorded at univ1
Local event recorded at UNIV operated by the universities in Prague and Patras

  • Apr. 18, 2003

  • 12:49

  • M 2.5

  • UNIV:

    D=5 km

    A=126o


April 18 2003 m 2 5 at univ 5 km
April 18, 2003 operated by the universities in Prague and Patras M 2.5at UNIV (5 km)

GPS recovered “itself”


April 18 2003 m 2 5 at univ 5 km1
April 18, 2003 operated by the universities in Prague and Patras M 2.5 at UNIV(5 km)

HF instrumental noise in 3T

LF instrumental noise in 5T

(complementary)


Conclusion
Conclusion operated by the universities in Prague and Patras

  • joint deployment of 3T BB and 5T SM revealed problems of both instruments

  • HF noise peak (30 Hz) on horiz. comp. of 3T

  • white accel. noise of 5T

  • occasional disturbances on horiz. 3T (tilt ?)

  • temporary timing (GPS, digitizer) problems


Instrumentally corrected records are rarely correct to every detail

Instrumentally “corrected” records are rarely correct operated by the universities in Prague and Patrasto every detail.

Joint deployment of

the 3T (BB) and 5T (SM) helps to reveal problems, and the instruments complement each other.


All data available from http seis30 karlov mff cuni cz
All data available from operated by the universities in Prague and Patrashttp://seis30.karlov.mff.cuni.cz

Thank you !


ad