U.S. Department of the Interior
U.S. Geological Survey
News Release
October 3, 2006 Diane Noserale 703-648-4333 dnoseral@xxxxxxxx
Gregory Stewart 207-622-8201, ext.118 gstewart@xxxxxxxx
Water in Monitoring Well Still
Dropping…
Maine Earthquake Lowers Ground
Water
View the Acadia National Park
well level at:
http://waterdata.usgs.gov/me/nwis/uv/?site_no=442238068154101&PARAmeter_cd=72019
A minor earthquake that shook Maine
Oct. 2 at 8:07 pm caused the water level in a U.S. Geological Survey (USGS)
monitoring well to drop more than 2 ½ feet. Nearly 17 hours later,
the groundwater level was still dropping, according to scientists at the
USGS Maine Water Science Center in Augusta. Hydrologists call the
change in the well “dramatic,” and note that well-water users could notice
changes in their drinking water. USGS hydrologists will continue to monitor
this well several times per day.
The preliminary magnitude 3.9 earthquake
was the third such event to shake up residents in Maine in the past few
weeks. This event was centered about 4 miles south-southeast of Bar Harbor,
or 45 miles southeast of Bangor, Maine. A magnitude 2.5 earthquake on Sept
28 and a magnitude 3.4 on Sept. 22 were centered in the same location.
“It isn’t unusual for earthquakes
to cause minor changes in water levels in wells, but this is the most memorable
in Maine in the last decade,” said USGS hydrologist Gregory Stewart. “Users
of well water could notice cloudy water and possibly a change in availability
of water,” said Stewart, who notes that the region’s fractured bedrock
means it is difficult to predict whether or not other wells will be affected.
“Water-level responses can occur over time periods of a few minutes to
several months.”
The well, located in Acadia National
Park in Bar Harbor, is a drilled bedrock well that is 98 feet deep. On
a normal day, water-level changes are generally 3-4 inches at this well.
One other well near the epicenter also showed a drop in water level from
this event. Other local earthquakes in the past two weeks were not detected
at water level monitoring wells in the state.
Monday’s earthquake was widely
felt in coastal and central Maine. More than a thousand citizens
from about 176 zip codes have reported light to moderate shaking on the
USGS Did You Feel It website: http://pasadena.wr.usgs.gov/shake/STORE/Xtib1_06/ciim_display.html
Although this series of felt earthquakes
is notable for this area, Maine has been shaken by stronger events. Several
minor earthquakes centered in Maine are recorded each year; many are too
small to be felt.
The largest earthquake centered
in Maine occurred March 21, 1904. Its magnitude was 5.1. This
event toppled chimneys and was widely felt throughout New England. Historic
earthquakes centered outside Maine have been large enough to cause damage
in the state. The largest historic earthquake to shake the region
was a magnitude 7.0 earthquake in 1663, centered in Quebec along the St.
Lawrence River. It toppled chimneys in eastern Massachusetts. In
1755, a magnitude 6.0 earthquake off Cape Ann, Mass. shook down chimneys
and several brick buildings in eastern Mass.
More information on the earthquake
history of Maine is found on: http://earthquake.usgs.gov/regional/states.php?regionID=19®ion=Maine
USGS serves the nation by providing
reliable scientific information to: describe and understand the Earth;
minimize loss of life and property from natural disasters; manage water,
biological, energy, and mineral resources; and enhance and protect our
quality of life.
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Diane Noserale
Media Relations, Eastern Region
U.S. Geological Survey
150 National Center
Reston, VA 20192
phone: 703-648-4333
fax: 703-648-4588
