The following figures present the focal mechanisms tabulated below. The color red is use to rep[resent focal mechanisms determined for the current year.
| Date_Time (UT) | Lat | Lon | Depth(km) | Mw | Strike | Dip | Rake | Reference |
| 19620202_064334 | 36.37 | -89.51 | 8 | 4.23 | 350 | 84 | 145 | JGR79 |
| 19630303_173011 | 36.64 | -90.05 | 15 | 4.66 | 304 | 78 | -28 | ENG97 |
| 19650814_131356 | 37.22 | -89.31 | 2 | 3.60 | 280 | 70 | -20 | JGR79 |
| 19651021_020438 | 37.48 | -90.94 | 5 | 4.60 | 260 | 40 | -70 | JGR79 |
| 19660101_132338 | 42.80 | -78.20 | 2 | 4.27 | 110 | 70 | 20 | JGR79 |
| 19660123_015638 | 37.00 | -107.00 | 3 | 4.99 | 336 | 46 | -99 | BSSA80 |
| 19670410_190000 | 39.90 | -104.80 | 4 | 4.52 | 165 | 52 | -174 | BSSA81a |
| 19670613_190854 | 42.90 | -78.20 | 3 | 4.08 | 130 | 50 | 40 | JRG79 |
| 19670721_091449 | 37.44 | -90.44 | 15 | 4.04 | 350 | 60 | 135 | ENG97 |
| 19670809_132500 | 39.90 | -104.70 | 3 | 4.84 | 130 | 35 | -90 | BSSA81a |
| 19671127_050900 | 40.00 | -104.70 | 5 | 4.52 | 158 | 52 | -63 | BSSA81a |
| 19681109_170142 | 37.91 | -88.37 | 22 | 5.29 | 0 | 46 | 79 | JGR79 |
| 19701117_021355 | 35.86 | -89.95 | 16 | 4.10 | 220 | 75 | 150 | JGR79 |
| 19711002_031928 | 64.40 | -86.50 | 12 | 4.63 | 162 | 72 | 90 | JGR79 |
| 19720203_231109 | 33.31 | -80.58 | 2 | 4.36 | 260 | 40 | 10 | BSSA86 |
| 19720915_052215 | 41.60 | -89.40 | 13 | 4.12 | 170 | 70 | 160 | JGR79 |
| 19730615_010904 | 45.30 | -70.90 | 6 | 4.49 | 300 | 80 | 70 | JGR79 |
| 19731130_074841 | 35.80 | -84.00 | 13 | 4.08 | 190 | 70 | 150 | JGR79 |
| 19740403_230502 | 38.55 | -88.07 | 15 | 4.34 | 310 | 70 | 0 | JGR79 |
| 19740802_085211 | 33.91 | -82.53 | 2 | 3.96 | 350 | 65 | 100 | BSSA86 |
| 19750613_224027 | 36.54 | -89.68 | 9 | 3.74 | 85 | 60 | -20 | JGR79 |
| 19750709_145415 | 45.70 | -96.00 | 8 | 4.30 | 330 | 90 | 160 | JRG79 |
| 19760204_000457 | 34.70 | -112.50 | 12 | 4.63 | 120 | 40 | -100 | BSSA81b |
| 19760325_004120 | 35.59 | -90.48 | 12 | 4.62 | 220 | 65 | 150 | JGR79 |
| 19760325_010011 | 35.59 | -90.48 | 16 | 4.23 | 45 | 80 | -150 | JGR79 |
| 19780616_114653 | 33.00 | -100.70 | 3 | 4.51 | 260 | 60 | -60 | EQN80 |
| 19800727_185221 | 38.17 | -83.91 | 12 | 5.04 | 30 | 60 | 180 | BSSA82 |
| 19820109_125351 | 46.98 | -66.66 | 10 | 5.47 | 200 | 45 | 120 | SRL92 |
| 19820109_163642 | 47.02 | -66.65 | 6 | 4.73 | 215 | 60 | 130 | SRL92 |
| 19820111_214107 | 46.98 | -66.65 | 8 | 5.14 | 200 | 60 | 125 | SRL92 |
| 19820119_001442 | 43.50 | -71.60 | 8 | 4.22 | 200 | 35 | 120 | SRL92 |
| 19820121_003354 | 35.17 | -92.21 | 6 | 4.38 | 330 | 60 | 55 | SRL92 |
| 19831007_101846 | 43.94 | -74.26 | 9 | 4.83 | 170 | 70 | 115 | SRL92 |
| 19841018_153023 | 42.37 | -105.72 | 25 | 5.25 | 350 | 60 | -25 | SRL92 |
| 19860131_164643 | 41.65 | -81.16 | 6 | 4.63 | 25 | 80 | 165 | SRL92 |
| 19860712_081939 | 40.55 | -84.39 | 4 | 4.40 | 20 | 80 | -170 | SRL88 |
| 19870610_234853 | 38.71 | -87.95 | 10 | 4.96 | 135 | 70 | 15 | SRL89 |
| 19900926_131851 | 37.16 | -89.58 | 15 | 4.28 | 140 | 75 | 50 | ENG97 |
| 19910504_011854 | 36.56 | -89.83 | 8 | 4.13 | 90 | 67 | 20 | ENG97 |
| 19940116_004342 | 40.34 | -76.01 | 3 | 4.00 | 121 | 60 | 66 | SRL98 |
| 19940116_014916 | 40.34 | -76.05 | 3 | 4.60 | 135 | 49 | 68 | SRL98 |
| 19940205_145537 | 37.36 | -89.19 | 16 | 3.85 | 30 | 70 | 170 | ENG97 |
| 19950128_062621 | 44.51 | -114.83 | 13 | 4.23 | 155 | 70 | -30 | WEB |
| 19950414_003255 | 30.26 | -103.30 | 20 | 5.61 | 114 | 64 | -101 | CHANG |
| 19961129_054132 | 35.97 | -90.00 | 11 | 3.78 | 120 | 65 | -15 | WEB |
| 19970516_012320 | 40.58 | -114.99 | 11 | 3.99 | 30 | 50 | -100 | WEB |
| 19971024_083517 | 31.20 | -87.30 | 4 | 4.90 | 94 | 62 | -90 | tWEB |
| 19980102_072829 | 38.18 | -112.46 | 16 | 4.52 | 235 | 50 | 20 | WEB |
| 19980428_141301 | 34.94 | -98.51 | 19 | 3.88 | 120 | 70 | -60 | WEB |
| 19980620_211620 | 43.26 | -110.59 | 9 | 4.15 | 15 | 80 | -55 | WEB |
| 19980823_181616 | 43.83 | -111.03 | 14 | 3.85 | 205 | 55 | 10 | WEB |
| 19980925_195252 | 41.49 | -80.39 | 2 | 4.47 | 110 | 70 | 20 | SRL00 |
| 19981212_014132 | 37.46 | -116.29 | 11 | 4.24 | 350 | 60 | -160 | WEB |
| 19981222_011746 | 48.00 | -115.20 | 12 | 3.85 | 230 | 80 | 25 | WEB |
| 19990630_152732 | 40.64 | -111.58 | 15 | 3.55 | 155 | 50 | -85 | WEB |
| 19990820_135026 | 44.78 | -112.77 | 14 | 4.83 | 260 | 40 | -140 | WEB |
| 19990909_113843 | 38.89 | -111.99 | 12 | 3.87 | 215 | 65 | -75 | WEB |
| 19991022_175115 | 38.08 | -112.73 | 6 | 4.00 | 180 | 40 | -140 | WEB |
| 19991222_080331 | 38.76 | -111.59 | 4 | 3.97 | 185 | 65 | -95 | WEB |
| 20000130_144653 | 41.52 | -109.81 | 7 | 4.10 | 30 | 75 | 80 | WEB |
| 20000307_021604 | 39.75 | -110.83 | 13 | 3.99 | 150 | 20 | -35 | WEB |
| 20000408_113021 | 46.39 | -111.44 | 11 | 3.85 | 200 | 70 | 35 | WEB |
| 20000524_042206 | 46.35 | -111.39 | 11 | 3.99 | 200 | 55 | 35 | WEB |
| 20000526_215846 | 42.18 | -107.56 | 12 | 3.84 | 225 | 60 | 10 | WEB |
| 20000527_215818 | 38.33 | -108.86 | 13 | 3.77 | 125 | 60 | -15 | WEB |
| 20000628_142830 | 46.69 | -113.58 | 12 | 4.13 | 115 | 70 | -155 | WEB |
| 20001012_093233 | 40.53 | -119.51 | 8 | 3.82 | 70 | 60 | -35 | WEB |
| 20001110_191405 | 46.40 | -111.38 | 13 | 3.79 | 190 | 80 | 50 | WEB |
| 20001119_125430 | 40.49 | -119.51 | 11 | 3.93 | 65 | 65 | -25 | WEB |
| 20001124_042006 | 44.82 | -110.59 | 6 | 4.46 | 110 | 65 | -110 | WEB |
| 20000901_190259 | 37.70 | -115.85 | 9 | 3.62 | 70 | 85 | -20 | WEB |
| 20010223_214350 | 38.73 | -112.56 | 10 | 4.28 | 195 | 40 | -85 | WEB |
| 20010421_171856 | 42.92 | -111.39 | 10 | 5.10 | 349 | 47 | -105 | WEB |
| 20010504_064212 | 35.19 | -92.19 | 5 | 4.34 | 20 | 85 | -165 | WEB |
| 20010719_201534 | 38.74 | -111.55 | 2 | 4.23 | 190 | 65 | -100 | WEB |
| 20010904_124553 | 37.15 | -104.64 | 3 | 4.18 | 215 | 30 | -80 | WEB |
| 20010905_105207 | 37.14 | -104.47 | 2 | 4.44 | 190 | 25 | -130 | WEB |
| 20020129_043658 | 43.58 | -110.61 | 16 | 3.79 | 30 | 80 | -15 | WEB |
| 20020131_181745 | 40.28 | -107.70 | 11 | 3.87 | 290 | 70 | 40 | WEB |
| 20020324_104407 | 37.01 | -115.10 | 11 | 4.06 | 180 | 65 | -170 | WEB |
| 20020331_183501 | 43.16 | -110.73 | 9 | 3.70 | 325 | 35 | -135 | WEB |
| 20020420_105044 | 44.51 | -73.66 | 10 | 4.97 | 360 | 35 | 80 | WEB |
| 20020618_173713 | 37.97 | -87.78 | 19 | 4.50 | 120 | 80 | 10 | WEB |
| 20021022_041116 | 43.18 | -110.83 | 11 | 4.33 | 355 | 55 | -105 | WEB |
| 20021103_204156 | 42.81 | -98.90 | 8 | 4.14 | 90 | 50 | -110 | WEB |
| 20021111_233928 | 32.36 | -80.07 | 9 | 4.00 | 350 | 40 | 90 | WEB |
| 20030103_050212 | 41.27 | -111.82 | 13 | 3.87 | 170 | 60 | -75 | WEB |
| 20030417_010419 | 39.55 | -111.88 | 2 | 4.13 | 185 | 50 | -85 | WEB |
| 20030429_085937 | 34.55 | -85.50 | 12 | 4.59 | 275 | 75 | 5 | WEB |
| 20030505_163232 | 37.75 | -78.07 | 5 | 3.55 | 3 | 71 | 158 | WEB |
| 20030525_073233 | 43.10 | -101.75 | 15 | 3.93 | 85 | 60 | -130 | WEB |
| 20030529_225214 | 38.26 | -117.90 | 11 | 3.82 | 270 | 85 | -15 | WEB |
| 20030606_122933 | 36.89 | -88.99 | 5 | 4.02 | 165 | 85 | 15 | WEB |
| 20030608_101454 | 41.22 | -116.36 | 11 | 3.79 | 75 | 80 | 85 | WEB |
| 20030816_050920 | 36.80 | -91.72 | 5 | 3.71 | 25 | 80 | -165 | WEB |
| 20030821_075654 | 44.09 | -110.53 | 5 | 4.20 | 295 | 55 | -100 | WEB |
| 20030913_152241 | 36.85 | -104.99 | 4 | 4.05 | 170 | 55 | -100 | WEB |
| 20031115_201159 | 38.22 | -117.87 | 6 | 4.14 | 274 | 85 | -10 | WEB |
| 20031115_211937 | 38.22 | -117.87 | 10 | 4.07 | 264 | 70 | -15 | WEB |
| 20031123_121959 | 40.73 | -115.15 | 10 | 4.19 | 25 | 50 | -90 | WEB |
| 20031222_191556 | 35.70 | -121.10 | 7 | 6.54 | 115 | 35 | 80 | WEB |
| 20040107_075138 | 43.57 | -110.38 | 5 | 4.80 | 145 | 55 | -145 | WEB |
| 20040107_084421 | 43.57 | -110.38 | 13 | 3.95 | 130 | 75 | -155 | WEB |
| 20040107_092347 | 43.60 | -110.35 | 15 | 3.89 | 220 | 75 | 25 | WEB |
| 20040317_235307 | 35.73 | -121.07 | 5 | 4.62 | 105 | 55 | 70 | WEB |
| 20040322_120956 | 36.85 | -104.85 | 4 | 4.39 | 175 | 55 | -95 | WEB |
| 20040407_155412 | 43.61 | -110.36 | 8 | 3.73 | 220 | 75 | -5 | WEB |
| 20040516_012940 | 37.27 | -114.96 | 6 | 3.97 | 350 | 75 | -160 | WEB |
| 20040523_092205 | 32.53 | -104.56 | 3 | 3.92 | 345 | 50 | -120 | WEB |
| 20040615_083421 | 36.73 | -89.68 | 2 | 3.49 | 175 | 55 | 70 | WEB |
| 20040622_085528 | 32.53 | -104.58 | 2 | 3.57 | 5 | 70 | -110 | WEB |
| 20040628_061052 | 41.44 | -88.96 | 7 | 4.15 | 20 | 90 | -165 | WEB |
| 20040630_122145 | 42.17 | -120.30 | 9 | 4.63 | 160 | 60 | -120 | WEB |
| 20040716_032517 | 36.86 | -89.16 | 5 | 3.46 | 140 | 70 | 20 | WEB |
| 20040716_121730 | 40.63 | -95.56 | 12 | 3.53 | 290 | 55 | -135 | WEB |
| 20040801_065046 | 36.89 | -104.92 | 4 | 4.28 | 155 | 65 | -120 | WEB |
| 20040804_235526 | 43.69 | -78.25 | 3 | 3.19 | 125 | 65 | 35 | WEB |
| 20040814_201443 | 43.17 | -111.02 | 8 | 3.63 | 20 | 75 | -60 | WEB |
| 20040816_210554 | 46.68 | -121.50 | 11 | 4.02 | 60 | 60 | 20 | WEB |
| 20040819_060603 | 44.66 | -124.31 | 23 | 4.70 | 155 | 65 | 75 | WEB |
| 20040819_235149 | 33.18 | -86.93 | 4 | 3.63 | 30 | 30 | -100 | WEB |
| 20040826_231131 | 64.76 | -86.28 | 23 | 4.24 | 155 | 60 | 80 | WEB |
| 20040912_130519 | 39.61 | -85.75 | 13 | 3.83 | 320 | 75 | 15 | WEB |
| 20040928_171524 | 35.81 | -120.37 | 8 | 5.89 | 140 | 85 | -155 | WEB |
| 20041001_192218 | 37.40 | -117.11 | 9 | 3.87 | 355 | 85 | -155 | WEB |
| 20041107_112025 | 32.97 | -87.90 | 3 | 4.25 | 35 | 40 | -115 | WEB |
| 20041116_182128 | 42.00 | -120.45 | 12 | 3.95 | 150 | 75 | -130 | WEB |
| 20041121_155032 | 44.35 | -114.01 | 13 | 3.86 | 195 | 60 | 55 | WEB |
| 20050128_223707 | 34.71 | -111.00 | 4 | 3.76 | 135 | 75 | -15 | WEB |
| 20050130_113750 | 34.76 | -111.08 | 3 | 4.00 | 90 | 65 | -100 | WEB |
| 20050210_140453 | 35.75 | -90.23 | 14 | 4.11 | 55 | 80 | -165 | WEB |
| 20050306_061749 | 47.75 | -69.73 | 12 | 4.58 | 350 | 30 | 80 | WEB |
| 20050501_123732 | 35.83 | -90.15 | 8 | 4.22 | 315 | 60 | 20 | WEB |
| 20050602_113510 | 36.14 | -89.46 | 15 | 3.89 | 155 | 65 | 70 | WEB |
| 20050611_111610 | 42.27 | -120.07 | 14 | 3.61 | 0 | 45 | -45 | WEB |
| 20050620_122141 | 36.95 | -88.96 | 4 | 3.60 | 320 | 80 | 15 | WEB |
| 20050726_040836 | 45.40 | -112.55 | 10 | 5.47 | 115 | 55 | -140 | WEB |
| 20050726_071246 | 45.43 | -112.61 | 13 | 3.84 | 275 | 85 | -130 | WEB |
| 20050727_155146 | 45.39 | -112.62 | 12 | 3.99 | 360 | 55 | -15 | WEB |
| 20050728_022930 | 45.50 | -112.43 | 12 | 3.54 | 105 | 40 | -130 | WEB |
| 20050729_140718 | 45.42 | -112.60 | 11 | 3.52 | 170 | 40 | -15 | WEB |
| 20050729_204618 | 38.78 | -112.10 | 12 | 3.82 | 275 | 50 | 45 | WEB |
| 20050807_052834 | 45.50 | -112.57 | 12 | 3.68 | 330 | 50 | -50 | WEB |
| 20050810_220817 | 36.95 | -104.86 | 4 | 4.88 | 160 | 40 | -110 | WEB |
| 20050812_205348 | 42.20 | -120.04 | 13 | 3.95 | 55 | 35 | -10 | WEB |
| 20050825_030941 | 35.88 | -82.80 | 8 | 3.65 | 90 | 60 | -60 | WEB |
| 20050916_150944 | 39.00 | -119.56 | 12 | 4.06 | 200 | 65 | -50 | WEB |
| 20050928_052732 | 44.60 | -116.07 | 11 | 3.84 | 170 | 65 | 20 | WEB |
| 20050928_231800 | 44.56 | -115.99 | 8 | 3.64 | 160 | 50 | 0 | WEB |
| 20050928_232045 | 44.61 | -116.05 | 8 | 3.79 | 170 | 70 | 30 | WEB |
| 20050929_135015 | 44.49 | -116.06 | 9 | 3.85 | 355 | 75 | 55 | WEB |
| 20051002_011001 | 44.54 | -115.99 | 7 | 3.84 | 150 | 30 | -65 | WEB |
| 20051031_002330 | 44.90 | -113.45 | 14 | 4.46 | 190 | 25 | -25 | WEB |
| 20051121_175232 | 44.83 | -111.53 | 16 | 3.54 | 325 | 65 | -55 | WEB |
| 20051219_202740 | 32.52 | -104.57 | 5 | 4.14 | 230 | 40 | -85 | WEB |
| 20060111_100236 | 43.55 | -127.19 | 29 | 5.30 | 215 | 60 | 15 | WEB |
| 20060118_094745 | 45.42 | -112.57 | 12 | 4.03 | 10 | 70 | -25 | WEB |
| 20060205_032552 | 44.74 | -111.88 | 13 | 4.43 | 135 | 35 | -45 | WEB |
| 20060210_214813 | 39.55 | -107.43 | 9 | 3.80 | 75 | 35 | -100 | WEB |
| 20060216_122832 | 66.93 | -135.83 | 11 | 4.12 | 85 | 90 | 30 | WEB |
| 20060218_130131 | 66.50 | -142.11 | 13 | 4.17 | 70 | 85 | -20 | WEB |
| 20060305_104216 | 64.93 | -129.26 | 2 | 5.42 | 290 | 45 | 85 | WEB |
| 20060329_033654 | 66.41 | -142.23 | 6 | 4.30 | 225 | 70 | 15 | WEB |
| 20060407_083140 | 47.38 | -70.46 | 25 | 3.77 | 15 | 55 | 85 | WEB |
| 20060518_101621 | 44.17 | -110.34 | 8 | 3.84 | 200 | 40 | -30 | WEB |
| 20060524_042027 | 32.35 | -115.19 | 12 | 5.09 | 215 | 45 | -90 | WEB |
| 20060607_040403 | 43.35 | -111.37 | 8 | 3.31 | 185 | 60 | -90 | WEB |
| 20060611_100150 | 40.25 | -111.07 | 14 | 3.50 | 235 | 25 | 35 | WEB |
| 20060617_162214 | 45.60 | -111.91 | 10 | 3.83 | 175 | 50 | -55 | WEB |
| 20060618_000533 | 45.60 | -111.90 | 10 | 4.17 | 305 | 60 | -120 | WEB |
| 20060620_201118 | 41.84 | -81.17 | 4 | 3.55 | 275 | 75 | 0 | WEB |
| 20060630_165501 | 42.43 | -111.50 | 10 | 4.15 | 10 | 65 | -70 | WEB |
| 20060714_093446 | 47.00 | -68.79 | 17 | 3.48 | 170 | 25 | 45 | WEB |
| 20060714_170601 | 42.43 | -111.54 | 10 | 3.96 | 10 | 75 | -70 | WEB |
| 20060826_005004 | 66.26 | -142.49 | 21 | 4.48 | 230 | 75 | -20 | WEB |
| 20060827_025823 | 66.27 | -142.14 | 22 | 4.33 | 235 | 80 | -15 | WEB |
| 20060827_032005 | 66.30 | -142.25 | 20 | 4.35 | 225 | 75 | -15 | WEB |
| 20060901_234449 | 66.43 | -142.44 | 3 | 4.41 | 50 | 75 | 15 | WEB |
| 20060902_195459 | 42.43 | -111.53 | 9 | 3.62 | 15 | 70 | -65 | WEB |
| 20061003_000737 | 44.33 | -68.17 | 2 | 3.87 | 340 | 35 | 85 | WEB |
| 20061008_024827 | 46.85 | -121.60 | 12 | 4.31 | 255 | 40 | 25 | WEB |
| 20070103_143438 | 37.06 | -104.90 | 2 | 4.38 | 205 | 50 | -60 | WEB |
| 20070109_154935 | 59.37 | -136.87 | 13 | 5.59 | 275 | 60 | 30 | WEB |
| 20070124_113015 | 37.41 | -117.08 | 9 | 3.83 | 265 | 90 | -10 | WEB |
| 20070225_035221 | 42.47 | -110.67 | 11 | 3.96 | 325 | 70 | -75 | WEB |
| 20070228_114741 | 41.06 | -114.77 | 12 | 3.58 | 60 | 70 | -25 | WEB |
| 20070302_044000 | 37.93 | -122.14 | 12 | 4.30 | 80 | 80 | 10 | WEB |
| 20070305_180622 | 58.81 | -134.44 | 1 | 3.81 | 35 | 35 | 85 | WEB |
| 20070329_053931 | 45.34 | -112.58 | 11 | 3.71 | 5 | 50 | -60 | WEB |
| 20070410_163425 | 69.73 | -144.68 | 18 | 4.49 | 205 | 65 | 25 | WEB |
| 20070427_154250 | 37.10 | -115.27 | 10 | 3.82 | 260 | 80 | 10 | WEB |
| 20070428_052030 | 69.65 | -144.79 | 21 | 4.87 | 205 | 90 | 0 | WEB |
| 20070508_154649 | 45.39 | -112.13 | 10 | 4.36 | 345 | 55 | -85 | WEB |
| 20070523_190915 | 22.02 | -96.27 | 11 | 5.60 | 190 | 75 | -160 | WEB |
| 20070525_134018 | 25.96 | -110.05 | 6 | 4.55 | 315 | 80 | -160 | WEB |
| 20070609_104544 | 36.93 | -104.79 | 4 | 3.35 | 195 | 50 | -60 | WEB |
| 20070610_180606 | 66.27 | -142.30 | 12 | 4.27 | 235 | 95 | 5 | WEB |
| 20070611_010346 | 37.50 | -114.04 | 8 | 3.90 | 260 | 75 | -5 | WEB |
| 20070612_072343 | 37.54 | -118.88 | 14 | 4.55 | 40 | 75 | -5 | WEB |
| 20070614_215757 | 45.13 | -120.95 | 18 | 3.58 | 255 | 85 | 20 | WEB |
| 20070625_023226 | 41.13 | -124.81 | 28 | 4.88 | 215 | 65 | 0 | WEB |
| 20070806_055945 | 37.81 | -114.43 | 8 | 3.87 | 110 | 55 | 10 | WEB |
| 20070818_131630 | 38.07 | -113.31 | 10 | 4.11 | 95 | 65 | -55 | WEB |
| 20070901_183202 | 41.64 | -112.33 | 9 | 3.66 | 245 | 85 | 5 | WEB |
| 20070908_071540 | 33.67 | -108.86 | 9 | 3.58 | 255 | 80 | 70 | WEB |
| 20070924_062054 | 45.10 | -123.03 | 20 | 3.65 | 125 | 90 | -45 | WEB |
| 20071031_030454 | 37.43 | -121.77 | 9 | 5.48 | 235 | 85 | -15 | WEB |
| 20071103_153532 | 66.32 | -135.43 | 6 | 4.57 | 70 | 70 | 20 | WEB |
| 20071103_195505 | 66.05 | -142.17 | 13 | 3.90 | 240 | 70 | 0 | WEB |
| 20071105_214800 | 39.36 | -111.64 | 15 | 3.76 | 230 | 25 | -65 | WEB |
| 20071128_125818 | 66.19 | -135.45 | 22 | 4.04 | 25 | 70 | -45 | WEB |
| 20071129_222744 | 66.38 | -142.29 | 13 | 4.64 | 70 | 80 | -35 | WEB |
| 20080103_135310 | 66.32 | -142.55 | 10 | 3.84 | 50 | 80 | 15 | WEB |
| 20080117_194645 | 67.93 | -136.28 | 18 | 4.92 | 250 | 70 | 15 | WEB |
| 20080130_100707 | 62.43 | -137.05 | 12 | 4.29 | 85 | 40 | 60 | WEB |
| 20080221_141605 | 41.08 | -114.77 | 11 | 5.91 | 30 | 40 | -90 | WEB |
| 20080221_235752 | 41.05 | -114.92 | 9 | 4.61 | 255 | 35 | -40 | WEB |
| 20080222_015006 | 41.02 | -114.93 | 11 | 3.86 | 230 | 55 | -60 | WEB |
| 20080222_232746 | 41.04 | -114.85 | 12 | 4.32 | 225 | 40 | -85 | WEB |
| 20080227_075939 | 41.12 | -114.67 | 11 | 4.12 | 90 | 85 | 10 | WEB |
| 20080228_151039 | 41.04 | -114.90 | 10 | 3.98 | 250 | 40 | -50 | WEB |
| 20080311_194225 | 69.82 | -146.66 | 18 | 4.26 | 5 | 65 | 15 | WEB |
| 20080315_162235 | 41.09 | -114.92 | 10 | 3.57 | 45 | 45 | -95 | WEB |
| 20080325_115938 | 44.70 | -110.05 | 12 | 4.21 | 5 | 60 | -30 | WEB |
| 20080327_010714 | 36.50 | -113.64 | 10 | 3.72 | 220 | 70 | -50 | WEB |
| 20080401_131617 | 41.22 | -114.82 | 12 | 4.12 | 85 | 50 | -15 | WEB |
| 20080407_095113 | 28.92 | -98.82 | 4 | 4.86 | 45 | 45 | -100 | WEB |
| 20080418_093700 | 38.45 | -87.89 | 14 | 5.23 | 25 | 90 | -175 | WEB |
| 20080418_151416 | 38.48 | -87.89 | 14 | 4.61 | 225 | 80 | -180 | WEB |
| 20080421_053830 | 38.47 | -87.82 | 15 | 4.00 | 210 | 85 | 175 | WEB |
| 20080422_204009 | 41.22 | -114.81 | 11 | 3.83 | 45 | 30 | -55 | WEB |
| 20080424_224704 | 39.53 | -119.93 | 7 | 3.73 | 240 | 75 | 15 | WEB |
| 20080424_225548 | 39.55 | -119.89 | 8 | 4.27 | 245 | 85 | 30 | WEB |
| 20080425_173100 | 38.45 | -87.87 | 13 | 3.72 | 295 | 80 | 5 | WEB |
| 20080426_064010 | 39.52 | -119.93 | 8 | 4.89 | 240 | 80 | 15 | WEB |
| 20080428_113318 | 39.57 | -119.91 | 5 | 4.04 | 135 | 90 | -175 | WEB |
| 20080505_112544 | 38.48 | -90.41 | 19 | 2.75 | 105 | 60 | 30 | WEB |
| 20080508_055502 | 39.54 | -119.92 | 10 | 3.59 | 25 | 85 | -25 | WEB |
| 19901019_070157 | 46.47 | -75.59 | 11 | 4.60 | 141 | 42 | 90 | DU |
| 19931116_093144 | 45.20 | -73.46 | 12 | 3.90 | 144 | 45 | 96 | DU |
| 19940116_004245 | 40.34 | -76.01 | 2 | 4.00 | 156 | 45 | 108 | DU |
| 19940116_014916 | 40.34 | -76.05 | 2 | 4.60 | 159 | 48 | 102 | DU |
| 19950616_121311 | 44.29 | -71.91 | 6 | 3.70 | 95 | 50 | 40 | DU |
| 19960314_104226 | 45.99 | -74.43 | 6 | 3.70 | 136 | 36 | 98 | DU |
| 19960821_075414 | 44.18 | -71.35 | 7 | 3.40 | 144 | 60 | 93 | DU |
| 19970524_185206 | 45.81 | -74.19 | 22 | 3.60 | 96 | 33 | 60 | DU |
| 19971028_114418 | 47.67 | -69.91 | 5 | 4.30 | 27 | 66 | 111 | DU |
| 19971106_023433 | 46.75 | -71.35 | 12 | 4.50 | 39 | 63 | 87 | DU |
| 19980730_085722 | 46.17 | -74.72 | 9 | 3.70 | 150 | 27 | 75 | DU |
| 19990316_125048 | 49.69 | -66.39 | 5 | 4.40 | 30 | 63 | 93 | DU |
| 20000101_112258 | 46.87 | -78.90 | 10 | 4.60 | 116 | 68 | 69 | DU |
| 20000420_084655 | 43.95 | -74.25 | 6 | 3.60 | 150 | 54 | 120 | DU |
| 20010126_030319 | 41.99 | -80.83 | 5 | 3.90 | 5 | 79 | 159 | DU |
| Code | Reference |
| BSSA80 | Herrmann, R. B., J. Dewey and S.-K. Park (1980). The Dulce, New Mexico earthquakes of January, 1966 Bull. Seism. Soc. Am. 70, 2171-2183. |
| BSSA81 | Herrmann, R. B., C. Y. Wang and S. -K. Park (1981). The Denver earthquakes of 1967-1968, Bull. Seism. Soc. Am. 71, 731-746. |
| BSSA81b | Eberhart-Phillips, D., R. M. Richardson, M. L. Sbar and R. B. Herrmann (1981). Analysis of the 4 February 1976 Chino Valley, Arizona Earthquake, Bull. Seism. Soc. Am. 71, 787-802. |
| BSSA82 | Herrmann, R. B., C. A. Langston, and J. E. Zollweg (1982). The Sharpsburg, Kentucky earthquake of July 27, 1980, J. E. Zollweg ), Bull Seism. Soc. Am. 72, 1219-1239. |
| BSSA86 | Herrmann, R. B. (1986). Surface-wave studies of some South Carolina earthquakes, Bull. Seism. Soc. Am. 76, 111-121. |
| DU | Du, Wen-xuan; Kim, Won-Young; Sykes, Lynn R. (2003). Earthquake Source Parameters and State of Stress for the Northeastern United States and Southeastern Canada from Analysis of Regional Seismograms, Bull. Seism. Soc. Am. 93, 1633 - 1648. |
| CHANG | Chang, T.-M. (1997). Evaluation of Surface-Wave Waveform Modeling for Lithosphere Velocity Structure, Ph.D. Disserations, Saint Louis Unviersity, PDF 3,167 kbytes ). |
| EQN80 | Voss, J. A. and R. B. Herrmann (1980). A surface wave study of the June 16, 1978 Texas earthquake, Earthquake Notes 51, 3-14. |
| ENG97 | Herrmann, R. B., and C. J. Ammon (1997). Faulting parameters of earthquakes in the New Madrid, Missouri region, Engineering Geology 46, 299-311. |
| JGR79 | Herrmann, R. B. (1979). Surface wave focal mechanisms for eastern North American earthquakes with tectonic implications, J. Geophys. Res.84, 3543-3552. |
| SRL88 | Schwartz, S. Y., and D. H. Christensen (1988). The 12 July St. Marys, Ohio earthquake and recent seismicity in the Anna, Ohio seismogenic zone, Seism. Res. Letters 59,, 57-62. |
| SRL89 | Taylor, K. B., R. B. Herrmann, M. W. Hamburger, G. L. Pavlis, A. Johnston, C. Langer and C. Lam (1989). The southeastern Illinois earthquake of 10 June 1987, Seism. Res. Letters 60, 101-110. |
| SRL92 | Nguyen, B. V., and R. B. Herrmann (1992). Determination of source parameters for central and eastern North American earthquakes (1982-1986), Seism. Res. Letters 63, 567-586. |
| SRL98 | Ammon, C. J., R. B. Herrmann, C. A. Langston, and H. Benz (1998). Source parameters of the January 16, 1994 Wyomissing Hills, Pennsylvania earthquakes, Seism. Res. Letters 69, 261-269. |
| SRL00 | Maceira, M., C. J. Ammon and R. B. Herrmann (2000). Faulting parameters of the September 25, 1998 Pymatuning, Pennsylvania earthquake, Seism. Res. Letters 71, 742-752. |
| tWEB | Not yet places on the web page |
| WEB | Digital Data Focal Mechanism Page |
The following file gives the focal mechanism information used to create the table shown above. This ASCII file has the following infomation in the columns: Event date, latitude, longitude, broadband depth, moment magnitude, strike, dip, rake, and citation. The citation is the same as that above. The relation between seismic moment, M0 and moment magnitude Mw is log M0 = 1.5 Mw + 16.05, where the seismic moment is in units of dyne-cm.
Since Nuttli developed the mbLg magnitude scale for the central United States, this magnitude is often reported by SLU and the USGS. Different magniude scales are based on different sesimci phases and frequenices. The mbLg scale uses the Lg phase and frequencies near 1.0 Hz. The Mw scale is base on the low frequency signal from the earthquake and a regional model of seismic velocities in the upper part of the Earth. These two scales differ.
We used the reported MLg(GS) values reported by the USGS and the
Mw report here to examine this diffference. The following figure
displays the difference between these magnitudes for the central United States.
The blue symbols are for earthquakes in the centrla and southeastern US and the red symbols are for earthquakes in the northeastern United States and SE Canada.