M 7.6 - 191 km S of ‘Ohonua, Tonga

  • 2009-03-19 18:17:40 (UTC)
  • 23.043°S 174.660°W
  • 31.0 km depth

Origin

Available Origin Products
CatalogMagnitudeTimeDepthReview StatusLocationSource
US 7.6 mwc 18:17:40 31.0 km REVIEWED 23.043°S 174.660°W US
ISCGEM 7.6 mw 18:17:41 39.9 km REVIEWED 23.134°S 174.581°W US ISCGEM
GCMT 7.6 mwc 18:17:40 34.0 km AUTOMATIC 23.050°S 174.660°W US
CHOY 7.8 me 18:17:40 40.0 km REVIEWED 23.050°S 174.660°W US
DUPUTEL 7.6 mww 18:17:40 50.5 km AUTOMATIC 23.050°S 174.660°W US DUPUTEL

Moment Tensor

Available Moment Tensor Products
CatalogTensorMagnitudeDepth% DCSource
DUPUTEL 7.6 Mww 50.5 km 81 % US DUPUTEL
US 7.6 Mww 45.0 km 83 % US
US 7.6 Mwc 49.1 km 90 % US LD
US 7.6 Mwc 47.0 km 98 % US

Finite Fault

Available Finite Fault Products
CatalogMagnitudeMaximum SlipSource
US 7.7 Mw 1.6 m US

Focal Mechanism

Available Focal Mechanism Products
CatalogMechanismNodal Plane 1Nodal Plane 2Source
US GCMT CHOY 215° , 65° , 120° 341° , 38° , 43° US US US
US GCMT CHOY 205° , 44° , 98° 14° , 46° , 82° US US US
US GCMT CHOY 215° , 65° , 120° 341° , 38° , 43° US US US

Subduction Zone Geometry Analysis

Most Likely Geometry: Strike = 198.34, Dip = 15.0
Most Likely Depth if on Planar Slab Interface = 14.98 km
Most Likely Depth if on Polynomial Slab Interface = 15.32 km

Basemap of subduction zone showing the area of the trench constrained in this example. Earthquake locations from the gCMT catalog and EHB catalog (gray circles, sized according to magnitude) are shown. Maroon rectangle indicates the area shown in cross section (c); all earthquakes within this area may be used to constrain trench geometry.
Variation in dip of best-fitting fault planes from the gCMT catalog for all events used to constrain trench geometry across the plane of the cross-section. Individual event dips are shown with small dark gray circles, sized with magnitude. Large mechanisms indicate the average dip in 20km bins across the plane of the cross-section. Light gray mechanisms represent a bulk average; dark gray represents a moment-weighted average.
Maximum Likelihood probability function describing interface dip probability over a range of dips from 0-60 degrees. Vertical black dashed line indicates the planar solution with an SVD inversion.
Least Squares R-squared correlation and RMS misfit functions describing interface dip likelihood over a range of dips from 0-60 degrees.

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