PENNSYLVANIA QUAKES AND SEISMIC WINDOWS


Date Time EST Epicenter Mg/Int Lat Lon FM Per NM Syn Notes,
1663-Feb-05 17:30
St. Lawrence R. area
7.+ /X 46.5 72.5   3 -1 79 hrs. Felt sharply in NE,
1727-Nov-09 22:40
Newbury-Mass
/VIII 42.8 70.8   -2 -4 60 hrs. Ground waves. Rumble,
1737-Dec-18 23:00
New York City
/VII 40.8 74   -2 -3 28 hrs. Chimneys toppled,
1758-Apr-24 21:30
Annapolis-MD
  38.9 76.5 1 17 16 43 hrs. ,
1783-Nov-29 21:00
New Hamp.-Penn.
        4 5 40 hrs. Three separate shocks,
1791-May-18 04:11
East Haddam-Conn.
/VIII 41.5 72.5 0 0 15 2 hrs. Fish jumped from water,
1800-Mar-17  
Philadelphia
  39.8 75.2 6 4   54 hrs.  
1800-Nov-29  
Philadelphia
  39.8 75.2 -1 13 13 22 hrs.  
1840-Nov-11  
Philadelphia
  39.8 75.2 1 0   34 hrs.  
1840-Nov-14  
Philadelphia
  39.8 75.2 4 3   34 hrs. Wave on Delaware R,
1884-May-31  
Allentown
/V 40.6 75.5   6 6 4 hrs.  
1884-Aug-10 14:07
New York City
5.5/VII 40.6 74.0 4 0   96 hrs. Int. VI in Philadelpia
1889-Mar-08 18:40
Harrisburg-Reading
3.9 /VI 40 76.5 -9 -11 6 60 hrs. Ball of fire in sky,
1908-May-31 12:41
Allentown
/VI 40.6 75.5 14 11 -1 64 hrs. Maybe not tectonic,
1934-Oct-29 15:07
Erie
/V 42 80.2 6 9 -8 68 hrs. People left theaters,
1938-Jul-15 17:45
Clover Cr.-Henrietta
3.3/VI 40.4 78.2 3 18 18 8 hrs. Spring stopped flow,
1954-Jan-07 02:24
Sinking Spring-PA
/VI 40.3 76.1   2 5 74 hrs. Furniture upset,
1954-Feb-21 15:00
Wilkes-Barre
4.5 /VII 41.2 75.9 4 17 19 52 hrs. $1 million damage,
1954-Feb-23 22:55
Wilkes-Barre
/VI 41.2 75.9 6 19 21 52 hrs. Mains broken,
1961-Sep-14 21:17
Lehigh Valley
/V 40.8 75.5 20 20 5 8 hrs. Bricks from chimney,
1961-Dec-27 12:05
Bristol-Levittown
/V 40.5 74.8 6 16 21 5 days  
1964-May-12 01:45
Cornwall-PA
4.5 /VI 40.2 76.5   0 1 27 hrs.  
1968-Dec-10 04:13
Darby-NJ - Philadel.
2.5 /V 39.7 74.6 5 20 20 16 hrs. broke windows,
1972-Dec-07 22:00
New Holland-Akron
/VI 40.1 76.2 17 17 2 1 hr.!  
1978-Jul-16 01:39
Lancaster-New Prov.
3.1 /V 39.9 76.3 -3 -3   5 hrs.  
1978-Oct-06 19:26
Brunnerville
3.0 /V 40.0 76.5 -12 -9 3 61 hrs.  
1980-Mar-11 01:00
Abington-Arosley
3.7 /V 40.2 75.1 10 -5 -5 1 hr.!  
1980-Jul-27 13:52
Max.Kentucky Quake
5.2 /VII 38.2 83.9 ecl 0 -2   59 hrs. Felt 15 states, incl PA,
1984-Apr-22 20:36
Marticville-Conestoga
4.4 /VI 39.9 76.4 6 7   35 hrs. Foreshock Apr 18,
1991-Aug-15 02:15
Centre Hall-Coburn
3.0 /V 40.8 77.7 6 5 31 hrs.    
1993-May-10 04:14
Reading-Hamburg
2.8 /IV 40.3 76.0 4 5   46 hrs. 5 minor aftershocks,
1994-Jan-15 19:03
Reading
4.2 /V 40.3 76.0   5 2 76 hrs.  
1994-Jan-15 20:48
Reading
4.6 /VI 40.3 76.0   5 2 76 hrs. Max. centered in PA,
1997-Nov-13 22:44
Lititz-PA
3.0 /IV 40.2 76.3 -1 1   54 hrs.  
Note: 30 of 34 Penn. quakes (83%) were in standard Seismic Windows (Syz -1 thru Syz +6 days)
Only one (Newbury, Mass.) was clearly not related to a high tide period.
Bold type indicates a "Seismic Window" of increased, potential for earthquakes.
Underlined items for quakes within perigean spring tides with Sychroneity less than 37 hrs.
Mg = Magnitude
Int = Mercalli Intensity
Lat = South Latitude
Lon = West Longitude
e = Eclipse (et = Total Eclipse)
FM = Date of Full Moon in relation to Quake
Per = Perigee = Date of Perigee in relation to Quake
NM = Date of New Moon in relation to Quake
Sync = Synchroneity is time difference between Syzygy (new or full stage of the Moon) and Perigee (On same day, only 2 to 5 times per year)
Jim Berkland, Geologist, Nov 15, 1997
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