For the last three formats, coordinates of centers and corners are given in an (x,y,down) coordinate system, where, commonly, the x-axis points east, y-axis points north, and down-axis points down. The global coordinate system, on the other hand is a (north,east,down) system. Sorry for any confusion that results.
NOTE: For all formats, TYPE is set to negative if dislocation coordinates are in degrees (i.e., not projected).
1) Dunbar format (from DIS3D)--(obsolete):
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TYPE=+/-1 HALFLEN DU DL DIP STRIKE X1C X2C SS DS
HALFLEN = half-length of dislocation rectangle.
DU = distance measured downdip from surface to top of dislocation rectangle.
DL = distance measured downdip from surface to bottom of dislocation rectangle.
X1C = X1 coordinate of up-dip projected center of dislocation (i.e., at the surface).
( = latitude if 1-axis points north).
X2C = X2 coordinate of up-dip projected center of dislocation (i.e., at the surface).
( = longitude if 2-axis points east).
SS = strike-slip Burger's vector (meters). (+ is left-lateral)
DS = dip-slip Burger's vector (meters). (+ is normal-faulting)
2) Normal or "earthquake" format:
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TYPE=+/-2 LONCEN LATCEN DCEN STRIKE DIP HORLEN DIPLEN SS DS OP RAKE
X(KM) Y(KM) (KM) (KM) (KM) (M) (M) (M)
LONCEN, LATCEN or X,Y = coordinates of center of rectangular dislocation.
DCEN = vertical depth to center of rectangular dislocation.
DIP is positive if one is looking down-dip as left hand points toward STRIKE.
HORLEN = full horizontal length of rectangular surface.
DIPLEN = width of rectangle measured down-dip.
SS = strike-slip Burger's vector (meters). (+ is left-lateral)
DS = dip-slip Burger's vector (meters). (+ is normal-faulting for positive dips)
OP = opening mode Burger's vector (meters). (+ is expansion)
RAKE (optional) = rake angle for slip on this patch (not relevant if SS and DS
are given).
3) Ends format:
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TYPE=+/-3 LON1 LAT1 LON2 LAT2 DEPTHTOP DIP DIPLEN SS DS OP RAKE
X1 Y1 X2 Y2 (KM) (KM) (M) (M) (M)
LON1,LAT1 or X1,Y1 = coordinates of first top corner in KM.
LON2,LAT2 or X2,Y2 = coordinates of second top corner in KM.
DEPTHTOP = vertical depth to top of rectangle in KM.
DIP is positive if one is looking down-dip as left hand points toward second corner.
(STRIKE in type 3 is azimuth of vector pointing from first to second corner.)
DIPLEN = width of rectangle measured down-dip.
SS = strike-slip Burger's vector (meters). (+ is left-lateral)
DS = dip-slip Burger's vector (meters). (+ is normal-faulting for positive dips)
OP = opening mode Burger's vector (meters). (+ is expansion)
RAKE (optional) = rake angle for slip on this patch (not relevant if SS and DS
are given).
4) Triangle format:
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TYPE=+/-4 LON1 LAT1 DEPTH1 LON2 LAT2 DEPTH2 LON3 LAT3 DEPTH3 SS DS OP RAKE
X1 Y1 Z1 X2 Y2 Z2 X3 Y3 Z3 (M) (M) (M)
LON-LAT-DEPTH or X,Y,Z = coordinates of corners of triangle.
SS = strike-slip Burger's vector (meters). (+ is left-lateral)
DS = dip-slip Burger's vector (meters). (+ is normal-faulting for positive dips)
OP = opening mode Burger's vector (meters). (+ is expansion)
RAKE (optional) = rake angle for slip on this patch (not relevant if SS and DS
are given).
Vertical triangles should be viewed from the clockwise side in assigning dip-slip.