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This "Plate Motion Calculator" calculates the relative and absolute plate motion direction and speed at any point on the earth. The prototype of web-based plate motion calculator was developed by K. Tamaki. This calculator is a revised version by K. Okino using perl-CGI script.

Method of Calculation: Select plate motion model, plate (or plates) and input latitude and longitude of the point, then press the "Execute calculation" button.

Plate Model: NUVEL-1 NUVEL-1A NNR-NUVEL-1 NNR-NUVEL-1A HS3-NUVEL-1A (see references below)

Moving Plate: Africa Antarctica Arabia Australia Caribbea Cocos Eurasia India Nazca North America Pacific South America Juan de Fuca Philippiine

Fixed Plate: Africa Antarctica Arabia Australia Caribbea Cocos Eurasia India Nazca North America Pacific South America Juan de Fuca Philippiine (not used in NNR models)

Latitude[deg]: (North: positive, South : negative (ex. -15.5))

Longitude[deg]:(East: positive, West: negative (ex. -116.5))

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References of Models:

• NUVEL-1:(relative motion, Pacific plate fixed)
  • DeMets, C., R. G. Gordon, D. F. Argus, and S. Stein, Current plate motions, Geophys. J. Int., 101, 425-478, 1990.
• NUVEL-1A:(relative motion, Pacific plate fixed)
  • DeMets. C., R. G. Gordon, D. F. Argus, and S. Stein, Effect of recent revisions to the geomagnetic reversal time scale on estimate of current plate motions, Geophys. Res. Lett., vol. 21, no. 20, 2191-2194, 1994.
• NNR-NUVEL-1:(absolute plate motion, no-net rotation)
  • Argus D.F., R.G. Gordon, No-net-rotation model of current plate velocities incorporating plate motion model NUVEL-1. Geophys. Res. Lett. (18) 2039-2042, 1991.
• NNR-NUVEL-1A:(absolute plate motion, no-net rotation)
  • DeMets. C., R. G. Gordon, D. F. Argus, and S. Stein, Effect of recent revisions to the geomagnetic reversal time scale on estimate of current plate motions, Geophys. Res. Lett., vol. 21, no. 20, 2191-2194, 1994.
• HS3-NUVEL-1A:(absolute plate motion, relative to hotspot frame)
  • Gripp, A.E., and Gordon, R.G., Young tracks of hotspots and current plate velocities, Geophys. J. Int., 150, 321-361, 2002.

Please note that the velocity calculated based on NUVEL-1 and NUVEL-1A may be 4.5% and <2% faster than those measured by space geodetic methods by using VLBI/SLR.

• Gordon, R. G., Orbital dates and steady rates, Nature, 364, 760-761, 1993.

Used Equation:

• rotation vector
  • MωF= MωP - FωP = (ωx, ωy, ωz)

• rotation pole
  • plat = atan(ωz / sqrt (ωx*ωx+ωy*ωy))

• plon = atan(ωy/ωx)

• rotation rate
  • rate = sqrt(ωx*ωx+ωy*ωy*+ωz*ωz)

• velocity at a point (tlat,tlon)

• Vew = radius * cos (tlat)*rate*(sin(plat)-cos(plat)*tan(tlat)*cos(plon-tlon))

• Vns = radius * rate * cos(plat)*sin(tlon-plon)

• Velocity = sqrt (Vew*Vew + Vns*Vns)

• Direction = atan(Vew/Vns)

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Last revised : November 11 2010 S bug report to okino@aori.u-tokyo.ac.jp