SUNY Potsdam Helicorder Displays
!! NOTICE !!
This is an archived copy of the real pages that can be found at:
http://quakes.potsdam.edu/earthworm/welcome.html
The reason for this site is because I put a lot of effort into creating this, setting up the webserver, and basically making things work.
After seeing things change hands, and watching things not ever get updated, I fear the quakes.potsdam.edu pages will not be available forever.
So mainly this is for my personal archive, but this is also here for anyone interested in looking at some seismic traces.
Also, the below earthquake is something I lived through, and made the traces for -
plus it was one of very few 5.x+ earthquakes in the north country of New York within a century.
Questions or comments? Please contact [ eric at thern dot org ]
EARTHQUAKE! Saturday April 20th, 2002 - about 6:51am EST -- CLICK HERE TO SEE THE DATA!
Here is REAL-TIME data for all the SUNY Potsdam stations.
about a 2-5 minute delay for updates
BGR EHZ LD : Bangor, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
BRCN EHZ LD : Brasie Corners, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
CHIP EHZ LD : Chipman, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
MSNY EHZ LD : Massena, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
LOZ EHZ LD : Lake Ozonia, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
FINE EHZ LD : Fine, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
PTN EHZ LD : Potsdam, New York
10/01/2002 (00) | 09/30/2002 (00) | 09/29/2002 (00) | 09/28/2002 (00) | 09/27/2002 (00) | 09/26/2002 (00) | 09/25/2002 (00)
LOZ BHZ LD : Lake Ozonia, New York - Broadband BHZ
09/23/2002 (00) |
LOZ BHN LD : Lake Ozonia, New York - Broadband BHN
09/23/2002 (00) |
LOZ BHE LD : Lake Ozonia, New York - Broadband BHE
09/23/2002 (00) |
Description
These displays simulate actual seismograms that are routinely recorded
at SUNY Potsdam's Geology Department with computer equipment.
The siesmograms show a record of how the ground moved during a 24-hour period.
The siesmogram is 'read' like a book, from left to right and top to bottom
(this is the direction that time increases). As with a book, the right end
of any horizontal line 'connects' with the left end of the line below it.
The colors of the horizontal lines have no particular significance, but are
there to help you distinguish the different lines.
The vertical lines are not part of the seismogram, but are present to indicate
equal intervals of time. Time is indicated on the left-hand side in EST and
on the right-hand side in UCT.
When an earthquake occurs the seismogram
will show ground motion fluctuations that typically last from
several tens of seconds to many minutes depending on the size
of the earthquake. The height of the recorded waves on the seismogram
(wave amplitude) is a greatly magnified representation of the actual
ground motion. The magnification is roughly 100,000 times or more.
A recording of an earthquake has recognizable characteristics.
Typically, once can recognize the arrival of different
wave types: P (the fastest traveling waves), S, and Surface waves.
On these seismograms you may see local earthquakes in the Northern New York
area, parts of Canada, and even earthquakes throughout the world. Almost
any earthquake in the world having a magnitude of greater than 5.5 will be
seen on these seismograms. For distant earthquakes, be sure to look at one
of the "broad band" siesmograms. (SUNY Potsdam has a broadband station,
however it is offline at the moment). Broad-band seismic instruments are
particularly sensitive to low-frequency ground motions generated by large
earthquakes. Some types of seismic waves (for example surface waves) from
a distant earthquake will only be visible on broad band seismograms.
Not all the wiggles seen on the seismograms are due to earthquakes.
Anything that produces ground vibrations could be recorded, for example
a car that passes by the seismometer (this is why seismometers are typically located well away from roads).
Such noise is usually easy to distinguish from earthquake generated
signals because the the noise is often "spikey" in appearance.
Other interesting signals may be recorded as well. An example that
will show up in the Potsdam records is nearby quarry blasts.
(there are a few, the most notable one is only about 10 miles north of Potsdam).
Map Links to each of the stations
BGR = Bangor, New York
BRCN = Brasie Corners, New York
CHIP = Chipman, New York
FINE = Fine, New York
LOZ = Lake Ozonia, New York
MSNY = Massena, New York
PTN = Potsdam, New York
Top of this page
The SUNY Potsdam Seismic Network is run by Dr. Frank Revetta.
Earthworm setup and maintainance is a joint effort between Andrew McDermott and Eric Thern and the SUNY Potsdam Geology department.
[USGS] U.S. Geological Survey
[CNSS] Council of the National Seismic System
Earthworm Software
Earthworm Documentation
SUNY Potsdam Geology Department