Station TA K27A - Flueckinger Farm, Gordon, NE, USA

Network: TA - USArray Transportable Network (new EarthScope stations)

Nearby stations (2 deg radius)

Station Name (Lat, Lon) Start / End Elevation
K27A Flueckinger Farm, Gordon, NE, USA (42.70, -102.24) 2008-11-16 / 2599-12-31 1131 m
Crust2 Type:D5,thick Platform 2 km seds.
Thickness Estimate:32 km
Thickness StdDev:3.3 km
Vp/Vs Estimate:1.85
Vp/Vs StdDev:0.09
Vs Estimate:3.514 km/s
Poisson's Ratio:0.29
Peak Value:0.03
Assumed Vp:6.483 km/s
Ps Weight:0.33333334
PpPs Weight:0.33333334
PsPs Weight:0.33333328
Residual Complexity:0.655
Nearby stations H: +-
(2.0 deg) Vp/Vs: +-

20 with match > 90% ( 19.047619 %) and 29 with match > 80% ( 27.619047 %) out of 105.

Download stack as xyz text file.

Azimuth Distribution of Events:

Prior Results for this Station

Study Thickness Vp/Vs Vp Vs Poissons Ratio Extra
EARS 32 km 1.85 6.483 km/s 3.514 km/s 0.29
Crust2.0 46 km 1.78 6.483 km/s 3.648 km/s 0.27 D5,thick Platform 2 km seds.
Global Maxima 32 km 1.85 6.483 km/s 3.514 km/s 0.29 amp=0.033830084
Local Maxima 1 43 km 2.05 6.483 km/s 3.166 km/s 0.34 amp=0.020599533
Local Maxima 2 35 km 1.73 6.483 km/s 3.747 km/s 0.25 amp=0.018558666
Local Maxima 3 43 km 1.62 6.483 km/s 4.008 km/s 0.19 amp=0.015370585
Local Maxima 4 31 km 1.82 6.483 km/s 3.567 km/s 0.28 amp=0.014424007
Predicted Arrivals for vertical incidence
(zero ray parameter)
Ps4.17 SECOND
PpPs14.04 SECOND
PsPs/PpSs18.21 SECOND

Events Processed for this Station

Download zip of receiver functions as SAC

View Record Section

Plot maxima for each earthquake.

Events Used in the Stack

(29 events)
Radial Match Distance Baz FERegion Time Lat/Lon Depth Magnitude
97.90785 86.3 deg 245.11 deg Samoa Islands Region 2009/09/29 17:48:10 GMT (-15.5, -172.1) 18 km 7.1 MB, 8.1 MS, 8.1 MW, 8.0 MW
97.80223 93.3 deg 241.595 deg Tonga Islands Region 2009/03/19 18:17:40 GMT (-23.0, -174.7) 34 km 7.0 MB, 7.6 MS, 7.6 MW, 7.6 MW
97.724785 49.2 deg 146.171 deg Ecuador 2010/08/12 11:54:15 GMT (-1.3, -77.3) 207 km 6.4 MB, 7.1 MW, 7.1 MW
97.59949 71.8 deg 146.895 deg Northern Chile 2010/07/12 00:11:21 GMT (-22.1, -68.2) 115 km 6.1 MB, 6.3 MW, 6.2 MW
96.634796 81.5 deg 154.98 deg Near Coast Of Central Chile 2010/03/11 14:39:43 GMT (-34.3, -71.9) 11 km 6.7 MB, 7.0 MS, 6.9 MW, 6.9 MW
95.1639 67.6 deg 313.584 deg East Of Kuril Islands 2009/01/15 17:49:39 GMT (46.9, 155.2) 36 km 6.9 MB, 7.5 MS, 7.4 MW, 7.4 MW
94.719246 43.7 deg 126.667 deg Near Coast Of Venezuela 2009/09/12 20:06:24 GMT (10.7, -67.9) 10 km 6.3 MB, 6.4 MS, 6.3 MW, 6.3 MW
94.59567 53.8 deg 21.797 deg Norwegian Sea 2009/08/20 06:35:04 GMT (72.2, 0.9) 6.0 km 5.9 MB, 5.7 MS, 6.0 MW, 6.0 MW
93.99373 64.5 deg 145.659 deg Southern Peru 2009/07/12 06:12:47 GMT (-15.0, -70.4) 199 km 5.7 MB, 6.1 MW, 6.1 MW
93.7918 84.6 deg 157.451 deg Near Coast Of Central Chile 2010/07/14 08:32:21 GMT (-38.1, -73.3) 22 km 5.9 MB, 6.5 MS, 6.6 MW, 6.5 MW
93.53224 83.6 deg 157.156 deg Near Coast Of Central Chile 2010/09/09 07:28:01 GMT (-37.0, -73.4) 16 km 5.8 MB, 6.0 MS, 6.2 MW, 6.2 MW
93.26297 52.6 deg 148.388 deg Northern Peru 2010/05/19 04:15:44 GMT (-5.1, -77.5) 140 km 6.0 MB, 6.0 MW, 6.0 MW
93.12939 61.8 deg 316.597 deg Off East Coast Of Kamchatka 2010/07/30 03:56:13 GMT (52.5, 159.8) 23 km 6.1 MB, 6.3 MS, 6.3 MW, 6.3 MW
92.87177 49.6 deg 93.629 deg Northern Mid-Atlantic Ridge 2009/06/06 20:33:28 GMT (23.9, -46.1) 14 km 6.0 MB, 5.7 MS, 6.0 MW, 6.0 MW
92.4132 49.9 deg 12.557 deg North Of Svalbard 2009/03/06 10:50:29 GMT (80.3, -1.9) 9.0 km 6.6 MB, 6.5 MS, 6.5 MW, 6.4 MW
92.28606 38.8 deg 141.522 deg Panama 2009/07/04 06:49:35 GMT (9.6, -79.0) 38 km 6.0 MB, 5.5 MS, 6.0 MW, 6.0 MW
91.6456 76.0 deg 151.63 deg Near Coast Of Northern Chile 2010/03/26 14:52:07 GMT (-28.0, -70.8) 42 km 6.2 MB, 5.9 MS, 6.3 MW, 6.1 MW
91.63359 77.2 deg 315.69 deg Hokkaido, Japan Region 2009/06/05 03:30:33 GMT (41.8, 143.4) 29 km 6.0 MB, 6.3 MS, 6.4 MW, 6.4 MW
91.54791 86.5 deg 313.196 deg Near S. Coast Of Honshu, Japan 2009/08/09 10:55:55 GMT (33.2, 137.9) 297 km 6.5 MB, 7.1 MW, 7.1 MW
90.24824 37.6 deg 152.347 deg Off Coast Of Costa Rica 2009/08/13 09:37:35 GMT (7.9, -85.6) 10 km 5.8 MW, 5.3 MB
87.13969 53.5 deg 308.239 deg Rat Islands, Aleutian Islands 2009/07/06 14:53:12 GMT (50.4, 177.0) 22 km 6.0 MB, 5.8 MS, 6.1 MW, 6.0 MW
86.655495 38.0 deg 148.374 deg Costa Rica 2009/03/11 21:03:58 GMT (8.5, -83.2) 17 km 5.7 MB, 5.6 MS, 5.9 MW, 5.8 MW
86.62218 35.3 deg 12.642 deg Baffin Bay 2009/07/07 19:11:46 GMT (75.4, -72.5) 19 km 5.9 MB, 5.7 MS, 6.1 MW, 6.0 MW
84.94516 45.0 deg 307.517 deg Fox Islands, Aleutian Islands 2010/07/18 05:56:44 GMT (52.9, -169.8) 14 km 6.3 MB, 6.7 MS, 6.6 MW, 6.6 MW
84.15845 71.8 deg 147.03 deg Northern Chile 2010/03/04 22:39:26 GMT (-22.2, -68.3) 114 km 6.3 MB, 6.4 MW, 6.3 MW
82.98373 79.9 deg 154.15 deg Near Coast Of Central Chile 2008/12/18 21:19:28 GMT (-32.5, -71.7) 18 km 5.8 MB, 6.0 MS, 6.2 MW, 6.1 MW
80.70099 85.6 deg 166.407 deg West Chile Rise 2009/06/10 23:13:21 GMT (-41.7, -84.0) 10 km 5.7 MB, 5.2 MS, 5.7 MW, 5.6 MW
80.50028 74.0 deg 146.563 deg Salta Province, Argentina 2010/07/26 17:31:31 GMT (-24.1, -66.8) 193 km 5.6 MW, 5.3 MB, 5.5 MW
80.46786 71.9 deg 145.755 deg Chile-Bolivia Border Region 2009/07/14 18:38:08 GMT (-21.8, -67.1) 176 km 5.7 MW, 5.4 MB, 5.7 MW

Losers

(76 events)
Radial Match Distance Baz FERegion Time Lat/Lon Depth Magnitude Reason
93.37926 87.5 deg 245.479 deg Tonga Islands 2009/09/29 18:22:13 GMT (-16.1, -173.3) 10 km 5.7 MB
88.86815 54.0 deg 353.026 deg East Of Severnaya Zemlya 2009/10/07 20:52:13 GMT (81.6, 119.5) 8.0 km 5.7 MB, 5.1 MS, 5.8 MW, 5.8 MW
86.73228 81.4 deg 154.979 deg Near Coast Of Central Chile 2010/03/12 16:50:01 GMT (-34.2, -71.9) 7.0 km 6.1 MB, 5.4 MS, 5.8 MW, 5.7 MW
85.44348 89.8 deg 40.996 deg Crete, Greece 2009/07/01 09:30:10 GMT (34.2, 25.5) 19 km 6.1 MB, 6.3 MS, 6.4 MW, 6.4 MW
79.77224 91.5 deg 242.865 deg Tonga Islands 2009/07/30 20:05:34 GMT (-20.8, -174.3) 10 km 5.9 MB, 5.7 MS, 5.8 MW, 5.7 MW
79.69006 39.8 deg 148.548 deg South Of Panama 2009/10/22 00:51:39 GMT (6.7, -82.6) 18 km 5.5 MB, 5.4 MS, 5.9 MW, 5.9 MW
78.94973 43.9 deg 154.957 deg Off Coast Of Ecuador 2009/05/10 01:16:06 GMT (1.4, -85.2) 6.0 km 5.5 MB, 5.7 MS, 6.1 MW, 6.1 MW
76.68667 65.4 deg 144.798 deg Peru-Bolivia Border Region 2009/09/30 19:03:17 GMT (-15.6, -69.3) 255 km 5.9 MB, 5.8 MW
75.695946 86.9 deg 246.41 deg Tonga Islands 2010/07/25 03:39:17 GMT (-15.1, -173.5) 7.0 km 5.6 MB, 5.7 MS, 5.9 MW, 5.9 MW
74.357 78.6 deg 319.537 deg Eastern Sea Of Japan 2010/03/30 01:02:53 GMT (43.3, 138.4) 21 km 6.1 MB, 5.3 MS, 5.7 MW, 5.6 MW
73.31437 86.3 deg 245.317 deg Samoa Islands Region 2009/10/19 22:49:38 GMT (-15.4, -172.3) 18 km 6.2 MB, 5.7 MS, 6.0 MW, 5.9 MW
73.05303 57.2 deg 102.721 deg Northern Mid-Atlantic Ridge 2008/12/07 06:23:09 GMT (13.4, -44.8) 10 km 5.6 MB, 5.3 MS, 5.7 MW
72.54734 40.6 deg 169.042 deg Galapagos Islands Region 2009/03/15 03:14:31 GMT (2.4, -95.1) 10 km 5.5 MS, 5.4 MB, 5.8 MW, 5.8 MW
72.05357 44.9 deg 307.404 deg Fox Islands, Aleutian Islands 2010/07/18 19:48:04 GMT (52.8, -169.7) 10 km 5.6 MB, 5.6 MS, 6.0 MW, 6.0 MW
71.67457 81.6 deg 154.92 deg Near Coast Of Central Chile 2010/03/11 14:55:27 GMT (-34.3, -71.8) 18 km 6.5 MB, 6.7 MW
71.44489 75.6 deg 147.148 deg Salta Province, Argentina 2010/03/08 17:03:16 GMT (-25.7, -66.6) 10 km 5.6 MB, 5.5 MS, 5.8 MW
71.41956 87.8 deg 245.476 deg Tonga Islands 2009/10/02 01:07:39 GMT (-16.3, -173.5) 8.0 km 6.1 MB, 6.0 MS, 6.1 MW, 6.1 MW
70.105774 65.2 deg 317.057 deg Kuril Islands 2009/04/21 05:26:11 GMT (50.8, 155.0) 152 km 6.0 MB, 6.2 MW, 6.2 MW
70.04965 39.3 deg 182.502 deg Galapagos Triple Junction Region 2009/10/15 17:48:21 GMT (3.3, -103.8) 10 km 5.9 MB, 5.7 MS, 6.0 MW, 6.0 MW
69.82301 84.8 deg 157.448 deg Near Coast Of Central Chile 2010/07/14 15:05:50 GMT (-38.2, -73.2) 35 km 5.5 MS, 5.4 MB, 5.8 MW, 5.7 MW
68.54763 52.1 deg 152.675 deg Near Coast Of Northern Peru 2009/02/15 10:04:49 GMT (-5.9, -80.9) 21 km 5.8 MB, 5.7 MS, 6.1 MW, 6.1 MW
68.52694 84.5 deg 157.416 deg Near Coast Of Central Chile 2010/03/07 15:59:44 GMT (-38.0, -73.3) 27 km 5.5 MB, 5.6 MS, 5.8 MW, 5.8 MW
68.18233 73.4 deg 149.447 deg Northern Chile 2010/07/17 06:07:42 GMT (-24.7, -69.8) 49 km 5.7 MB, 5.5 MW, 5.5 MW
68.143875 84.0 deg 157.205 deg Near Coast Of Central Chile 2010/08/05 06:01:47 GMT (-37.4, -73.3) 18 km 5.5 MS, 5.4 MB, 5.9 MW, 5.8 MW
67.70751 83.2 deg 312.833 deg Near East Coast Of Honshu, Japan 2009/06/06 05:52:43 GMT (35.5, 140.9) 34 km 5.8 MB, 5.4 MS, 5.8 MW, 5.7 MW
67.48202 44.8 deg 307.131 deg Fox Islands, Aleutian Islands 2010/07/28 11:31:46 GMT (52.7, -169.4) 10 km 5.6 MW, 5.2 MS, 5.2 MB, 5.1 ML
67.24268 35.0 deg 194.099 deg East Central Pacific Ocean 2010/01/21 08:03:22 GMT (8.3, -110.4) 10 km 5.8 MB, 5.3 MS, 5.6 MW, 5.6 MW
67.08299 51.9 deg 72.908 deg Azores Islands Region 2009/11/04 18:41:44 GMT (36.2, -33.9) 10 km 5.7 MB, 5.6 MS, 5.9 MW, 5.8 MW
66.46656 56.9 deg 146.626 deg Peru-Brazil Border Region 2010/01/25 22:52:46 GMT (-8.5, -74.5) 147 km 5.7 MB, 5.9 MW, 5.9 MW
66.05281 96.5 deg 295.698 deg Mariana Islands 2010/07/10 05:39:43 GMT (14.0, 145.0) 136 km 5.6 MB, 5.6 MW, 5.5 MW
65.89291 91.1 deg 297.78 deg Mariana Islands Region 2010/08/22 09:33:06 GMT (19.4, 147.4) 23 km 5.9 MB, 5.3 MS, 5.5 MW
65.669304 54.7 deg 153.279 deg Off Coast Of Northern Peru 2010/07/04 06:57:44 GMT (-8.5, -80.5) 29 km 5.7 MW, 5.3 MB, 5.6 MW
65.50263 87.4 deg 245.896 deg Tonga Islands 2009/05/13 21:31:17 GMT (-15.8, -173.5) 85 km 5.8 MW, 5.3 MB, 5.8 MW
65.45688 50.4 deg 307.779 deg Andreanof Islands, Aleutian Is. 2009/06/22 21:05:33 GMT (51.3, -178.2) 29 km 5.5 MB, 5.0 MS, 5.4 MW, 5.4 MW
65.0456 79.3 deg 314.817 deg Near East Coast Of Honshu, Japan 2010/07/04 21:55:51 GMT (39.7, 142.4) 27 km 6.4 MB, 6.1 MS, 6.3 MW, 6.2 MW
64.7577 57.9 deg 143.175 deg Western Brazil 2009/01/29 22:28:05 GMT (-8.1, -71.4) 602 km 5.7 MW, 5.3 MB, 5.6 MW
64.41677 87.0 deg 245.984 deg Tonga Islands 2009/10/01 06:13:32 GMT (-15.4, -173.3) 10 km 5.6 MB, 5.7 MS, 5.8 MW, 5.7 MW
63.22391 83.0 deg 156.719 deg Near Coast Of Central Chile 2010/03/21 18:31:04 GMT (-36.3, -73.2) 36 km 5.6 MB, 5.1 MS, 5.5 MW, 5.5 MW
62.90539 70.4 deg 323.808 deg Sakhalin, Russia 2010/03/16 09:44:17 GMT (52.1, 142.2) 24 km 5.6 MB, 5.5 MS, 5.8 MW, 5.8 MW
62.422806 79.0 deg 315.267 deg Near East Coast Of Honshu, Japan 2009/02/15 09:24:31 GMT (40.2, 142.2) 33 km 6.1 MB, 5.5 MS, 5.7 MW, 5.7 MW
62.41541 64.6 deg 145.507 deg Southern Peru 2009/09/05 03:58:39 GMT (-15.1, -70.2) 210 km 5.8 MW, 5.2 MB, 5.8 MW
62.38904 80.2 deg 151.914 deg San Juan Province, Argentina 2009/03/11 13:06:53 GMT (-31.9, -69.2) 28 km 5.5 MB, 4.8 MS, 5.3 MW, 5.5 ML
62.149986 79.9 deg 151.227 deg San Juan Province, Argentina 2010/01/18 12:28:34 GMT (-31.4, -68.6) 94 km 5.5 MB, 5.4 MW, 5.4 MW
62.011307 72.3 deg 314.691 deg Kuril Islands 2009/10/13 10:15:13 GMT (44.6, 149.1) 40 km 5.6 MB, 5.2 MS, 5.7 MW, 5.6 MW
61.98749 77.5 deg 148.178 deg Catamarca Province, Argentina 2009/08/12 18:00:52 GMT (-27.9, -66.7) 174 km 5.5 MW, 5.3 MB, 5.5 MW
61.75168 79.9 deg 312.886 deg Off East Coast Of Honshu, Japan 2010/01/17 06:04:36 GMT (37.9, 143.6) 7.0 km 5.7 MB, 5.2 MS, 5.6 MW, 5.6 MW
61.517437 90.2 deg 38.301 deg Eastern Mediterranean Sea 2009/06/19 14:04:59 GMT (35.4, 28.5) 28 km 5.6 MB, 5.6 MS, 5.8 MW, 5.8 MW
61.514282 96.0 deg 245.389 deg South Of Fiji Islands 2009/06/08 04:33:19 GMT (-22.2, -179.6) 612 km 5.5 MW, 5.2 MB
61.03064 93.9 deg 316.319 deg Ryukyu Islands, Japan 2009/10/30 07:03:39 GMT (29.2, 129.8) 34 km 6.3 MB, 6.8 MS, 6.8 MW, 6.8 MW
60.261852 44.7 deg 307.097 deg Fox Islands, Aleutian Islands 2010/07/19 08:20:30 GMT (52.7, -169.3) 10 km 5.6 MW, 5.2 MS, 5.4 MB, 5.1 ML
59.876064 76.0 deg 151.881 deg Near Coast Of Northern Chile 2009/02/06 02:58:35 GMT (-28.0, -71.1) 52 km 5.5 MB
58.81524 34.7 deg 311.319 deg Kodiak Island Region, Alaska 2009/03/30 07:13:07 GMT (56.5, -152.7) 21 km 5.9 MB, 5.9 MS, 5.9 MW, 5.9 MW
57.19909 97.7 deg 240.499 deg South Of Fiji Islands 2010/08/04 04:46:20 GMT (-26.9, -177.2) 18 km 5.7 MB, 5.8 MS, 6.0 MW, 5.9 MW
56.256306 59.9 deg 194.535 deg Southern East Pacific Rise 2010/03/07 07:05:23 GMT (-16.2, -115.3) 10 km 5.8 MB, 5.7 MS, 6.3 MW, 6.2 MW
56.01701 73.4 deg 146.145 deg Jujuy Province, Argentina 2010/01/28 08:04:14 GMT (-23.4, -66.7) 208 km 5.8 MB, 5.9 MW, 5.9 MW
55.18391 92.4 deg 298.67 deg Mariana Islands 2008/12/02 12:31:43 GMT (19.1, 145.8) 137 km 5.9 MB, 5.9 MW, 5.9 MW
54.903374 64.0 deg 145.301 deg Central Peru 2009/03/15 08:19:05 GMT (-14.5, -70.4) 190 km 5.7 MW, 5.1 MB, 5.6 MW
54.404335 87.3 deg 244.067 deg Samoa Islands Region 2009/01/28 12:39:42 GMT (-17.0, -172.1) 10 km 5.6 MB, 5.3 MS, 5.5 MW
54.139328 71.0 deg 146.613 deg Chile-Bolivia Border Region 2008/12/04 16:47:09 GMT (-21.4, -68.3) 115 km 5.5 MB, 5.5 MW, 5.5 MW
53.337082 92.9 deg 299.54 deg Mariana Islands 2010/03/08 09:47:11 GMT (19.3, 144.7) 457 km 6.0 MB, 6.1 MW, 6.1 MW
52.410633 52.2 deg 309.87 deg Rat Islands, Aleutian Islands 2009/10/07 05:38:37 GMT (52.2, 178.1) 138 km 5.6 MB, 5.6 MW, 5.6 MW
52.233437 72.8 deg 188.705 deg Easter Island Region 2009/09/10 19:46:03 GMT (-29.9, -111.8) 10 km 5.5 MW, 5.4 MB
51.834732 81.6 deg 312.625 deg Off East Coast Of Honshu, Japan 2008/12/20 10:29:23 GMT (36.5, 142.4) 19 km 6.0 MB, 6.3 MS, 6.3 MW, 6.3 MW
51.71925 86.8 deg 245.19 deg Samoa Islands Region 2009/09/29 23:45:03 GMT (-15.8, -172.6) 10 km 6.0 MB, 5.8 MS
51.608974 81.9 deg 152.32 deg Mendoza Province, Argentina 2010/02/12 12:03:38 GMT (-33.6, -68.8) 148 km 5.6 MB, 5.8 MW, 5.8 MW
51.08304 90.8 deg 316.814 deg Kyushu, Japan 2009/04/05 09:36:26 GMT (32.0, 131.4) 26 km 5.8 MB, 5.4 MS, 5.8 MW, 5.8 MW
50.580677 73.3 deg 315.146 deg Kuril Islands 2010/03/06 13:31:12 GMT (44.2, 147.6) 53 km 5.7 MW, 5.1 MS, 5.4 MB, 5.6 MW
48.82986 81.6 deg 312.69 deg Off East Coast Of Honshu, Japan 2008/12/21 09:16:44 GMT (36.5, 142.3) 13 km 5.6 MB, 5.7 MS, 5.9 MW, 5.9 MW
48.67328 77.3 deg 316.986 deg Hokkaido, Japan Region 2009/02/28 00:35:56 GMT (42.6, 142.1) 105 km 5.5 MB, 5.5 MW, 5.5 MW
48.590096 66.1 deg 316.239 deg Kuril Islands 2010/07/25 12:57:01 GMT (49.7, 154.6) 130 km 5.7 MB, 5.6 MW, 5.6 MW
47.668232 50.3 deg 307.681 deg Andreanof Islands, Aleutian Is. 2009/06/22 19:55:24 GMT (51.3, -178.2) 35 km 5.6 MB, 5.6 MW, 5.6 MW
45.91949 81.6 deg 155.136 deg Near Coast Of Central Chile 2010/03/11 15:06:02 GMT (-34.5, -72.0) 32 km 6.0 MB, 5.9 ML
45.101482 72.1 deg 189.214 deg Easter Island Region 2009/09/17 23:21:38 GMT (-29.1, -112.3) 10 km 5.7 MB, 6.0 MS, 6.2 MW, 6.2 MW
44.28974 91.4 deg 302.719 deg Volcano Islands, Japan Region 2009/07/29 14:52:08 GMT (22.6, 143.3) 140 km 5.5 MW, 5.2 MB, 5.4 MW
42.093857 92.2 deg 317.268 deg Kyushu, Japan 2009/09/03 13:26:18 GMT (31.1, 130.0) 166 km 5.9 MB, 6.2 MW, 6.2 MW
41.328682 92.3 deg 242.503 deg Tonga Islands 2009/08/13 11:17:01 GMT (-21.7, -174.6) 10 km 5.6 MW, 5.3 MB