Glenn Cougoulat – ISTerre

Vibrations study : seismological considerations in instrumentation

Les services d’observations – Coutant / Cougoulat - Nov 2014

Le service d’observation 100 sites permanents

2013 : + 56 sites mobiles

Faits marquants

Modernisation des sites RLBP

XX sites modernisés (infrastructures, communication,

acquisition)

XX sites multi-paramètres (GPS, Acc, BB)

Implémentation d’un système de surveillance

automatique de la sismicité des Alpes

SeiscomP3 - Shake-MapTM

Evaluation rapide des dommages

Expérience CIFALP-Pyrope

Développement d‘une chaîne efficace et performante

depuis l’installation jusqu’à la distribution des données

SO-ISTerreRéseaux Permanents et Mobiles

Les services d’observations – Coutant / Cougoulat - Nov 2014

Sismob-RESIF

Organization: 2 sub-pools (+1 obsolete) dedicated to different scientific targets

tomography of lithospheric targets (74 BB stations),

hazard studies (45 BB stations),

( antennas for studies of shallow structures at 100-m scale, site effects, unconventional seismic

sources etc.: 23 obsolete stations with short-period sensors)

Staff: 2 technical staff for instrument pool (1 fte = 0.2 IR + 0.8 AI); Databases: 4 technical

staff of RESIF-SI (0.55 fte = 0.4 IE + 0.13 IR + 0.02 AI); 1 scientist (0.1 fte)

Instruments of broad interest to all French seismologists interested in data acquisition

from temporary arrays (~50); Public release of data 3 years after end of experiment (see

RESIF-SI)

Funding (2013): 74 k€ = 70 k€ from INSU-CNRS + 4 k€ (user fee). Low user fee because

either it was paid in advance in 2011 (PYROPE, LIBRIS), or it will be paid in 2014 (RHUM-RUM,

DOMERAPI).

Instruments Type Nb

142 dataloggers Nanometrics Taurus 3-channels 119

Agecodagis 6 or 9 channels 23

307 velocimeters Broadband (120s) 3C – STS2 36

Wide-band (30, 60s) 3C – Güralp CMG40 90

Short-period (5s, 2Hz) 3C and 1C 181

20 accelerometers Güralp CMG5 20

119 stations

Les services d’observations – Coutant / Cougoulat - Nov 2014

ISTerre

Measures

Seismology

GPS

Extensometry

Weather, Temperature, Pressure, Rain

Electric

Photogrammétrie…

Field Isoled, mountain, landslides, urban

Les services d’observations – Coutant / Cougoulat - Nov 2014

ISTerre

Test facilities

Characterized test sites

Low noise condition

Calibration table for sensors =>

transfer function

Calibration electronics for digitizers

Les services d’observations – Coutant / Cougoulat - Nov 2014

Supervision : Poste d’observation

Outil de détection automatique Seiscomp

Local seismicity - Sismalp

HRI

HRI

HRI

Réponses instrumentales - Outils

Earth = Filter

Records =

seismogram

Seismic

source (s)

Earth =

Green

function

Measure =

seismometer +

digitizer

Earth = Filter

Low noise model

Usual controls - time

Usual control - frequency

Diurnal variations

Seasonal variations

• Velocity changes or timing check

Cross Correlation

Quality Control

Daily variation on the Z component at station CT26 No concrete slab at this station

PQLX software: Statistical analysis of the power spectral density

Vertical channels

USArray

FR permanent network

TA 127A

TA 135A

What about the horizontal channels…

North channels East channels Period = 100s

Earthquake sea of Okhotsk M=7.7

De

riva

tive

of

atm

osp

he

ric

pre

ssu

re d

(Pre

ssu

re)/

dt

PSD

me

an v

alu

e

Period = 20s Horizontal channels Z channel

PSD

mea

n v

alu

e

Period = 10s Horizontal channels Z channel

PSD

me

an v

alu

e

Time (days) from 08/01/12 to 08/20/12

Insulation developments

HRI developments Coutant et al.

HRI