When time allows, I'll post channel sets that I create to look at earthquakes on this "blog".

Instructions: To copy one of the channel sets on the iPad, press and hold your finger on part of the channel list. When you release you finger you will see text-selection handles. Select the channel set and choose copy. Then navigate to the seismogram settings tab and press and hold on the current channel list. When you release you will see text-selection options; choose Select All and then choose Paste to replace the current with a new set.

Tuesday
Sep242013

Southwestern Pakistan - 24 September, 2013, M 7.8

A large earthquake struck southwestern Pakistan at about 04:30 PM (Pakistan time). The USGS PAGER alert level is red. 

No real-time stations are located in the region, but the station NIL, located in norther Pakistant, and KBL, located in Kabul are at regional distances.

II; NIL; 00; BHZ; Nilore, Pakistan, Up-Down
II; NIL; 00; BH1; Nilore, Pakistan, North-South
II; NIL; 00; BH2; Nilore, Pakistan, East-West
IU; KBL; --; BHZ; Kabul, Afghanistan, Up-Down
IU; KBL; --; BHN; Kabul, Afghanistan, North-South
IU; KBL; --; BHE; Kabul, Afghanistan, East-West

Here is the mainshock recordings at those sites (displacement seismograms). Note that the local time in the plot is the local time where the plot was made, US EDT.

Here is a plot of the recent aftershock activity as seen at these stations (open the image in a new tab or window to see the full size).

Friday
Aug162013

Cook Strait, New Zealand - 16 August, 2013, M 6.5

The sequence of major and moderate earthquakes in the Cook Strait region between the North and South Islands of New Zealand moved to the South Island today. 

Seismic Station SNZO is located near Wellington on the southern North Island. Here is a plot of the mainshock (ground velocity) using the strong-motion sensor at the site (channel code 20) and components (HN1,2,Z). Here is a channel list suitable for recording aftershocks. Use the near filter settings to watch small aftershocks.

IU; SNZO; 00; BHZ; South Karori, New Zealand (UP-Down)
IU; SNZO; 00; BH1; South Karori, New Zealand (West-East)
IU; SNZO; 00; BH2; South Karori, New Zealand (North-South)

Here is a plot of the mainshock and the early aftershock activity. IT's hard for the USGS to detect the early aftershock just before 02:38 UTC. So it has no line identifying the origin time. 

Sunday
Jul212013

Cook Strait, New Zealand - 21 July, 2013, M 6.5

In the last few days several moderate-magnitude events occurred followed today by a M 6.5 earthquake in the Cooke Straight, between New Zealand's North and South Islands.

Seismic Station SNZO is located near Wellington on the southern North Island. Here is a plot of the mainshock (ground velocity) using the strong-motion sensor at the site (channel code 20) and components (HN1,2,Z).

 Here is a channel list suitable for recording aftershocks. Use the near filter settings.

IU; SNZO; 00; BHZ; South Karori, New Zealand (UP-Down)
IU; SNZO; 00; BH1; South Karori, New Zealand (West-East)
IU; SNZO; 00; BH2; South Karori, New Zealand (North-South)

Here is a plot of recent aftershocks observed at this station.

Sunday
Jun092013

Northern Territory, Australia - 09 June, 2013 - M 5.6

A moderate-size earthquake occurred in central Australia at 2013-06-09 14:22:13 UTC

A high quality seismometer is located relatively nearby in Warrakurna. Here is the channel information for that and another station nearby (part of the Alice Springs Seismic Array):

AU; WRKA; --; BHZ; Warrakurna, Western Australia (Up-Down)
AU; WRKA; --; BHE; Warrakurna, Western Australia(East-West)
AU; WRKA; --; BHN; Warrakurna, Western Australia (North-South)
AU; AS31; --; BHZ; Alice Springs, Australia (Up-Down)
AU; AS31; --; BHE; Alice Springs, Australia(East-West)
AU; AS31; --; BHN; Alice Springs, Australia (North-South)

Here are the mainshock displacements observed at Warrakurna:

To detect smaller aftershocks, you should use a filter from 1.0 to 4 hertz and you can choose a sample rate of 10 samples per second to reduce the file sizes.

 

Wednesday
May292013

Southern California - 29 May, 2013 - M 4.6

A small earthquake occurred off just off the coast of California this morning, about 20 km west of Santa Barbara.

A high quality seismometer is located in Santa Barbara. Here is the channel information:

CI; SBC; --; BHZ; Santa Barbara, CA, USA (Up-Down)
CI; SBC; --; BHE; Santa Barbara, CA, USA (East-West)
CI; SBC; --; BHN; Santa Barbara, CA, USA (North-South)

Here are the displacements (I integrated the original ground-velocity seismograms) recorded at seismic station SBC for the mainshock. I did not use any filters for these data. Note that I am on the east coast of the US, so local time for the plots is EDT.

 

Here is a more recent plot that shows the early aftershock activity. I applied the "Near" filters for this plot - it looks even more interesting if you set the filter "corners" to 1.0 and -4.0 (minus means don't apply the filter). The largest aftershock in the chart is a M 2.6 event at 14:50:02.

See earthquake.usgs.gov for details on the event.

Tuesday
Mar122013

Southern California - 11 March, 2013 - M 4.7

A magnitude 4.7 earthquake occurred in southern California on 11 March, 2013. See the US Geological Survey for information (earthquakes.usgs.gov). A map of the aftershocks is shown below. The red circles show the most recent aftershocks, the yellow show the "older" aftershocks. All these events occurred in the last few days. The symbol size is scaled by magnitude, but all the smallest events are shown with a uniformly small circle (the most common size circle on the map).

 

Here is a channel list for a station very close the the sequence.

AZ; TRO; --; BHZ; Toro Peak, CA, USA (Up-Down)
AZ; TRO; --; BHE; Toro Peak, CA, USA (East-West)
AZ; TRO; --; BHN; Toro Peak, CA, USA (North-South)

Here is a plot of the strong-motion instrument mainshock at this station and a plot of more recent, small aftershocks.

 

Tuesday
Feb052013

Northern Vanuatu Subduction Zone - 06 Feb, 2013 - M 8.0

A sequence of earthquakes that began about a week ago just added a great earthquake in the northermost segment of the northern Vanuatu subduction zone (near the Santa Cruz Islands region).

There are no close real-time stations in the region, but the aftershock sequence includes events large enough to see at greater distance.

 

Friday
Dec142012

Offshore southern California - 14 December, 2012 - M 6.4

A major earthquake occurred within the Pacific Plate off the coast of northern Baja California and southern California.

 

The event is quite a distance from the coast. However, there are some seismic stations within several tens of kilometers of the earthquake, so you may be able to see some of the larger aftershocks if you use the monitoring function. Here is a channel list for the station on San Clemente Island.

CI; SCI2; --; BHZ; San Clemente Island, CA, USA (Up-Down)
CI; SCI2; --; BHE; San Clemente Island, CA, USA (East-West)
CI; SCI2; --; BHN; San Clemente Island, CA, USA (North-South)

Here is a plot of the vertical, east-west and north-south displacement seismograms for the mainshock. I used the channel list above with no filters on the signal (other than the original seismometer response) and integrated the velocity seismograms to produce a displacement seismogram.

 

Here is a plot highlighting one of the early aftershocks (and a few other very small ones). I used the near filter with a sample rate of 10 samples per second with the above channel list to make the plot.

 

 

Saturday
Nov102012

Eastern Kentucky - 10 November, 2012 - M 4.3

A small earthquake occurred in eastern Kentucky this afternoon. The event was located within the earthscope transporatable array, so there is at least one seismometer withing a few 10's of km of the event. A channel list for one close station is listed below.

TA; T52A; --;BHZ;HALLIE,KY USA (UP-DOWN)
TA; T52A; --;BHE;HALLIE,KY USA (EAST-WEST)
TA; T52A; --;BHN;HALLIE,KY USA (NORTH-SOUTH)

 

A plot of the signals at this station showing the M 4.3 event and several aftershocks is shown below.

Here's an image showing the signals from the mainshock.

 

Wednesday
Nov072012

Off The Coast of Guatemala - 07 November, 2012 - M 7.4

The earthquake occured along the west coast of Guatemala; detailed information is available from the US Geological Survey at this site. The location is shown in the map below.

 Here are the seismograms from a global sample of seismic stations.

The following channels are for the closest station, which is operated by the Servicio Nacional de Estudios Territoriales (SNET) of El Salvador. 

SV;SNET;--;BHZ; El Salvador (UP-DOWN)
SV;SNET;--;BHE; El Salvador  (EAST-WEST)
SV;SNET;--;BHN; El Salvador  (NORTH-SOUTH)

Here is the mainshock on the El Salvadoran station

Another nearby station is

CU;TGUH;00;BHZ; Tegucigalpa, Honduras (UP-DOWN)
CU;TGUH;00;BH2; Tegucigalpa, Honduras  (EAST-WEST)
CU;TGUH;00;BH1; Tegucigalpa, Honduras  (NORTH-SOUTH)

You should be able to see the larger aftershocks on either.

Sunday
Oct282012

South of Masset, Canada - 28 October, 2012 - M 7.7

A large reverse-faulting earthquake occurred off the west coast of British Columbia last night. So far there have been many moderate-size aftershocks.

 

The following channels are for the closest station at Van Inlet, BC - so close that it may be experiencing some problems with power and communications. 

CN;VIB;--;HHZ; VAN INLET, BC, CANADA(UP-DOWN)
CN;VIB;--;HHE; VAN INLET, BC, CANADA (EAST-WEST)
CN;VIB;--;HHN; VAN INLET, BC, CANADA (NORTH-SOUTH)

This station is farther away, but seems to be more reliable relaying the data in real time

AT;CRAG;--;BHZ; CRAG ALASKA,AK, USA (UP-DOWN)
AT;CRAG;--;BHE; CRAG ALASKA,AK, USA (EAST-WEST)
AT;CRAG;--;BHN; CRAG ALASKA,AK, USA (NORTH-SOUTH)
Here are some of the recent aftershocks seen at Crag Alaska.
Sunday
Oct212012

Central California - 21 October, 2012 - M 5.3

The earthquake occured along the central California San Andreas Fault System; detailed information is available from the US Geological Survey at this site.

This part of central California is on of the places along the San Andreas Fault System with sparse broadband station availability through the seismogram servers that epicentral uses - there are plenty of seismometers down there, they just aren't available in real time through the standard sources. Here's a channel list for a seismic station operated by the University of California at Berkeley that is located about 50-75 km northwest of the earthquake, in the Hollister Hills region, just east of Salinas.

BK; SAO; 00; BHZ; SAO, HOLLISTER HILLS, CA, USA (VERTICAL);
BK; SAO; 00; BHE; SAO, HOLLISTER HILLS, CA, USA (EAST);
BK; SAO; 00; BHN; SAO, HOLLISTER HILLS, CA, USA (NORTH);

The mainshock signals are very clear (see below) and the larger aftershocks should show up well even at this distance. If you want to monitor the aftershock activity, you could stream (use the automatic updates every five minutes or so) about 30 minutes of data, enter a "10" in the Sample-Rate field, and use the "Near" filters.