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M7.1 - LUZON, PHILIPPINES - 2022/07/27 00:43:24 UTC | Geoscope

 LUZON, PHILIPPINES 2022/07/27 00:43:24 UTC,  Mw=7.1

 Earthquake description:
     Location (USGS) : LUZON, PHILIPPINES
     UTC Date (USGS) : 2022/07/27 00:43:24
     Latitude (USGS) : 17.598°
     Longitude (USGS) : 120.809°
     Magnitude (SCARDEC) : 7.1 Mw
     Depth (SCARDEC) : 25 km
     Mechanism (SCARDEC) :

SCARDEC method: Analysis of the earthquake source

SCARDEC method uses the teleseismic body waves to retrieve the depth, focal mechanism, moment magnitude and source time function of earthquakes with magnitudes larger than 5.5-6. Details of the methodology are described in Vallée et al. [2011] and an application to all earthquakes with magnitude larger than 6 in the period 1992-2011 can be found in Vallée [2013]. The consolidated SCARDEC catalog, with full access to earthquake parameters and source time functions, can be found here.

In the near-real time configuration presented here, the solution is typically posted 45 minutes after earthquake occurrence. Solution includes a map summing up the SCARDEC results and a figure showing the agreement to the data. The map presents the earthquake location (together with the plate boundaries from Bird [2003] and the slab contours of SLAB 1.0 [Hayes et al., 2012]) and the main SCARDEC source parameters. Numerical values of focal mechanism parameters and seismic moment are written below the map. The data agreement figure compares the SCARDEC synthetics (red) with the FDSN data (black), in the frequency range used for focal mechanism determination. The name of GEOSCOPE stations is written in green.


See more information (about the data, the procedure, the reasons that could prevent from providing the earthquake information, the source time function determination...) in the "detailed notes".

If using some of the SCARDEC results, please refer to:

(1) Vallée, M., J. Charléty, A.M.G. Ferreira, B. Delouis, and J. Vergoz, SCARDEC : a new technique for the rapid determination of seismic moment magnitude, focal mechanism and source time functions for large earthquakes using body wave deconvolution, Geophys. J. Int., 184, 338-358, 2011.

(2) Vallée, M., Source time function properties indicate a strain drop independent of earthquake depth and magnitude, Nature Communications, doi: 10.1038/ncomms3606, 2013.



The method is running and maintained at IPGP laboratory. Apart from IPGP, past and present support to the development of the method are/were provided by the following institutes/projects :

                                                                            


We are grateful to the organisms providing, managing or federating data:

                                                                      


is used for drawing some maps of the webpage.

 
 Automatic determination of source parameters using the SCARDEC method
 Interactive map of the regional seismicity of the last ten years (Magnitude > 5; Source USGS)
Earthquake depth [km]
Magnitude
9
8
7
6
5
: GEOSCOPE stations    -    The information about the plate tectonics are provided by USGS and Bird (2003)
 Interactive map of the foreshocks and aftershocks
(2 weeks before and 2 weeks after the earthquake - Source USGS)

Earthquake depth [km]
Foreshock Aftershock Mag.
7
6
5
4
3
The information about the plate tectonics are provided by USGS and Bird (2003)

 Earthquake data of the GEOSCOPE stations
      Download the data archive (20000 seconds of data)
Metadata in FDSN stationXML and channel information in text format
Time series in miniSEED format

List of miniSEED segments

 Theorical arrival times at GEOSCOPE stations
     Display arrival times at available GEOSCOPE stations

 Earthquake records

Code Location Lat. Lon. Elev. Description Records
AISNouvelle-Amsterdam - TAAF, France-37.796°77.569°0.036 kmShow station
description
Show
records
ATDArta Cave - Arta, Republic of Djibouti11.531°42.847°0.61 kmShow station
description
Show
records
CANCanberra, Australia-35.319°148.996°0.7 kmShow station
description
Show
records
CCDConcordia Base, Dome C, Antartica-75.107°123.305°3.24 kmShow station
description
Show
records
CRZFPort Alfred - Ile de la Possession - Crozet Islands, France-46.431°51.855°0.14 kmShow station
description
Show
records
DRVDumont d'Urville - Terre Adelie, Antarctica-66.665°140.002°0.04 kmShow station
description
Show
records
ECHEchery - Sainte Marie aux Mines, France48.216°7.159°0.58 kmShow station
description
Show
records
FDFMMorne la Rosette, Martinique, France14.735°-61.16°0.32 kmShow station
description
Show
records
FOMANahampoana Reserve - Fort Dauphin, Madagascar-24.976°46.979°0.028 kmShow station
description
Show
records
FUTUMaopo'opo, Futuna-14.308°-178.121°0.097 kmShow station
description
Show
records
HDCHeredia, Costa Rica10.002°-84.111°1.186 kmShow station
description
Show
records
INUInuyama, Japan35.35°137.029°0.132 kmShow station
description
Show
records
IVIIvittuut, Greenland61.206°-48.171°0.015 kmShow station
description
Show
records
KIPKipapa, Hawaii, USA21.42°-158.011°0.11 kmShow station
description
Show
records
MPGMontagne des Peres - French Guiana, France5.11°-52.644°0.147 kmShow station
description
Show
records
NOUCPort Laguerre - New Caledonia, France-22.099°166.307°0.137 kmShow station
description
Show
records
PAFPort aux Francais - Kerguelen - TAAF, France-49.351°70.211°0.017 kmShow station
description
Show
records
PELPeldehue, Chile-33.144°-70.675°0.7 kmShow station
description
Show
records
PPTFPamatai - Papeete - Tahiti island - French Polynesia, France-17.59°-149.565°0.705 kmShow station
description
Show
records
ROCAMLeguat Reserve, Rodrigues Island, Republic of Mauritius-19.756°63.37°0.052 kmShow station
description
Show
records
SANVUEspiritu Santo, Vanuatu-15.447°167.203°0.056 kmShow station
description
Show
records
SOKSop - Niakhar, Senegal14.494°-16.456°0.071 kmShow station
description
Show
records
SSBTunnel de Badole - Saint Sauveur en Rue, France45.279°4.542°0.7 kmShow station
description
Show
records
TAMTamanrasset, Algeria22.791°5.528°1.41 kmShow station
description
Show
records
UNMUnam - Mexico, Mexico19.33°-99.178°2.28 kmShow station
description
Show
records
WUSWushi - Xinjiang Uygur, China41.201°79.216°1.468 kmShow station
description
Show
records

 Records from LHZ channel of GEOSCOPE stations
     Download graphic file in PDF format

This figure illustrates how the two blocks separated by the seismic fault are displaced during the earthquake. These movements are deduced from the SCARDEC focal mechanism, on the two possible fault planes. Additional information (tectonics, near-fault measurements) is required to determine which one of these two hypotheses corresponds to the real movements during the earthquake.



1) Overview

This page gathers information on earthquake characteristics (through the SCARDEC method, see below) and on GEOSCOPE data available for these events: The “data” tab provides access to the data seed file (20000s window starting at the earthquake origin time), provides access to the theoretical arrival times, shows earthquake waveforms for each station and channel, and presents the global Earth wave propagation through the visualization of the LHZ channel. The “mechanism” tab illustrates the geometry of the movement during the earthquake, along the two possible faults planes determined by SCARDEC analysis.

Several e-mail alerts are available, as soon as a new earthquake has been analyzed: (1) for all earthquakes, (2) for earthquakes with Mw>=6.5, and (3) for earthquakes with Mw>=7. Please contact Martin Vallée (vallee@ipgp.fr) to be added in one of these mailing lists.


2) Analysis of the earthquake source (SCARDEC method)

SCARDEC method uses the teleseismic body waves to retrieve the depth, focal mechanism, moment magnitude and source time function of earthquakes with magnitudes larger than 5.5-6. Details of the methodology are described in Vallée et al. [2011] and an application to all earthquakes with magnitude larger than 6 in the period 1992-2011 can be found in Vallée [2013]. The consolidated SCARDEC catalog, with full access to earthquake parameters and source time functions, can be found here.

In the near-real time configuration presented here, the solution is typically posted 45 minutes after earthquake occurrence. Solution includes a map summing up the SCARDEC results and a figure showing the agreement to the data. The map presents the earthquake location (together with the plate boundaries from Bird [2003] and the slab contours of SLAB 1.0 [Hayes et al., 2012]) and the main SCARDEC source parameters. Numerical values of focal mechanism parameters and seismic moment are written below the map. The data agreement figure compares the SCARDEC synthetics (red) with the FDSN data (black), in the frequency range used for focal mechanism determination. The name of GEOSCOPE stations is written in green.


See more information (about the data, the procedure, the reasons that could prevent from providing the earthquake information, the source time function determination...) in the "detailed notes".

If using some of the SCARDEC results, please refer to:

(1) Vallée, M., J. Charléty, A.M.G. Ferreira, B. Delouis, and J. Vergoz, SCARDEC : a new technique for the rapid determination of seismic moment magnitude, focal mechanism and source time functions for large earthquakes using body wave deconvolution, Geophys. J. Int., 184, 338-358, 2011.

(2) Vallée, M., Source time function properties indicate a strain drop independent of earthquake depth and magnitude, Nature Communications, doi: 10.1038/ncomms3606, 2013.



The method is running and maintained at IPGP laboratory. Apart from IPGP, past and present support to the development of the method are/were provided by the following institutes/projects :

                                                                            


We are grateful to the organisms providing, managing or federating data:

                                                                      


is used for drawing some maps of the webpage.