December 27, 2001 Earthquake in Eastern Maine


Weston Observatory reports that a small earthquake occurred at 3:54:27 p.m. Eastern Standard Time on Thursday, December 27, 2001 northeast of Bangor in a sparsely populated part of eastern Maine.

The following parameters have been calculated for the earthquake (this is a preliminary determination):

Preliminary magnitude 2.8
Preliminary location 45 deg. 3 min. North latitude, 68 deg. 9 min. West longitude
Depth 22 kilometers
This places the epicenter near the south end of Nicatous Lake in northern Hancock County.

Further Information:

The Maine Geological Survey received only two felt reports, from Greenfield and Burlington. This is not surprising given the earthquake's small magnitude and relatively great depth, and also considering the low population density of the region.

Canadian Seismic Network Hourly plot for 20:00 to 21:00 (UT) on December 27, 2001. The earthquake registered on several instruments between 20:50 and 21:00.

Phase Data Listing of Weston Observatory. This table lists information about the earthquake recorded at seismic stations around the region. It also gives statistics related to calculating the time, location, and magnitude of the earthquake.

Epicenter

map showing epicenter of earthquake

December 27, 2001 Maine, Approximately 56 km ENE of Bangor

DATE ORIGIN LAT N LONG W DEPTH MN MC ML GAP RMS ERH ERZ Q
11227 2054 28.92 45-2.51 68- 9.36 21.68 2.8 130 0.39 4.6 7.0 C

STN DIST AZM RMK HRMN SEC TOBS TCAL RES WT AMX PRX XMAG FMP FMAG
UMM 66.3 124 IPD1 2054 39.86 10.95 11.19 -0.26 2.61 177 .14 2.3
S 4 2054 48.05 19.14 19.92 -0.80 0.00
WVL 132.4 245 IPD4 2054 44.65 15.73 20.44 -4.72 0.00 129 .24 2.5
S 4 2054 59.25 30.33 36.39 -6.07 0.00
PQI 181.4 3 EPD4 2054 63.23 34.31 26.50 7.79 0.00
S 4 2054 80.29 51.38 47.16 4.16 0.00
LMN 277.3 71 P 3 2055 9.90 40.98 38.34 2.65 0.00
A11 291.1 327 S 3 2055 39.06 70.15 71.28 -1.15 0.41
A16 305.2 332 P 1 2055 10.93 42.01 41.77 0.24 1.54
S 3 2055 42.71 73.79 74.36 -0.56 0.50
LBNH 312.3 253 P 0 2055 11.70 42.78 42.66 0.07 2.01
A54 320.0 327 P 1 2055 12.85 43.94 43.61 0.27 1.47
MOQ 323.4 275 P 1 2055 13.30 44.39 44.03 0.22 1.46
LMQ 324.9 329 P 0 2055 13.12 44.21 44.22 -0.08 1.94
S 2 2055 47.55 78.64 78.70 -0.19 0.97
FFD 329.2 238 EPD4 2055 16.27 47.35 44.75 2.61 0.00 276 .22 3.5
S 4 2055 60.74 91.82 79.65 12.18 0.00
A61 330.2 333 S 3 2055 48.21 79.29 79.86 -0.58 0.46
HNH 361.0 246 EPD4 2055 2.04 33.13 48.66 -15.57 0.00
S 4 2055 66.10 97.19 86.62 10.51 0.00
DPQ 402.2 297 P 1 2055 22.86 53.95 53.76 0.19 1.11
S 4 2055 61.81 92.90 95.69 -2.80 0.00
GSQ 437.8 10 P 1 2055 28.00 59.08 58.15 0.93 0.88
S 3 2055 72.15 103.23 103.50 -0.28 0.31
CNQ 473.7 1 P 3 2055 30.49 61.57 62.58 -1.03 0.22
S 4 2055 78.50 109.58 111.39 -1.85 0.00
ICQ 502.5 8 P 1 2055 35.00 66.08 66.14 -0.06 0.66
S 4 2055 85.25 116.33 117.72 -1.40 0.00
SMQ 586.3 11 P 1 2055 46.09 77.18 76.48 0.63 0.28
MNQ 612.0 356 P 1 2055 48.40 79.48 79.65 -0.17 0.17

Explanation of Table

Table Header: detailed hypocenter data

  1. Geographic location
  2. DATE = date event occurred, yr/mo/dy (year/month/day)
  3. ORIGIN = event origin time (UCT) in hours, minutes, and seconds
  4. LAT N = latitude north in degrees and minutes
  5. LONG W = longitude west in degrees and minutes
  6. DEPTH = event depth in kilometers
  7. MN = Nuttli Lg phase magnitude with amplitude divided by period
  8. MC = signal duration (coda) magnitude
    WES: 2.23 Log(FMP) + 0.12Log(Dist) - 2.36 (Rosario, 1979)
    MIT: 2.21 Log(FMP) - 1.7 (Chaplin et al., 1980)
  9. ML = local magnitude
    WES: calculated from Wood-Anderson seismograms (Ebel, 1982)
    GSC (Geological Survey of Canada): Richter Lg magnitude
  10. GAP = largest azimuthal separation, in degrees, between stations
  11. RMS = root mean square error of travel time residual in seconds
  12. ERH = standard error of epicenter in kilometers
  13. ERZ = standard error of event depth in kilometers
  14. Q = solution quality of hypocenter
    A = excellent
    B = good
    C = fair
    D = poor

Table Body: earthquake phase data

  1. STN = station name
  2. DIST = epicentral distance in kilometers
  3. AZM = azimuthal angle in degrees measured clockwise between true north and vector pointing from epicenter to station
  4. Description of onset of phase arrival
    I = impulsive
    E = emergent
  5. R = phase
    P = first P arrival
    S = first S arrival
  6. M = first motion direction of phase arrival
    U = up or compression
    D = down or dilatation
  7. K = weight of arrival
    0 = full weight (1.0)
    1 = 0.75 weight
    2 = 0.50 weight
    3 = 0.25 weight
    4 = no weight (0.0)
  8. HRMN = hour and minute of phase arrival
  9. SEC = second of phase arrival
  10. TCAL = calculated travel time of phase in seconds
  11. RES = travel time residual (error) of phase arrival
  12. WT = weight of phase used in hypocentral solution
  13. AMX = peak-to-peak ground motion, in millimicrons, of the maximum envelope amplitude of vertical-component signal, corrected for system response
  14. PRX = period in seconds of the signal from which amplitude was measured
  15. XMAG = Nuttli magnitude recorded at station
  16. FMP = signal duration (coda), in seconds, measured from first P arrival
  17. FMAG = coda magnitude recorded at station

Last updated on October 6, 2005