rotate {StratigrapheR}

Spherical rotation around fixed axes

Description

Spherical rotation around given rotation axes

Usage

rotate(dec, inc, rdec, rinc, rmag)

Arguments

dec

declination of the data; it is the angle from the north taken on an horizontal plane. It is measured clockwise from North and ranges from 0 to 360° (Tauxe 2010).

inc

inclination of the data; it is the angle from the horizontal, is positive downward, and ranges from +90° for straight down to -90° for straight up (Tauxe, 2010).

rdec

declination of the rotation axes (of length 1 or n).

rinc

inclination of the rotation axes (of length 1 or n).

rmag

magnitude of rotation (following the notation of the Stereonet software): a positive rotation is clockwise looking in the direction of the given declination and inclination; of length 1 or n).

References

• Tauxe, L., 2010. Essentials of Paleomagnetism. University of California Press.

• Allmendinger, R. W., Cardozo, N. C., and Fisher, D., 2013, Structural Geology Algorithms: Vectors & Tensors: Cambridge, England, Cambridge University Press, 289 pp.

• Cardozo, N., and Allmendinger, R. W., 2013, Spherical projections with OSXStereonet: Computers & Geosciences, v. 51, no. 0, p. 193 - 205, doi: 10.1016/j.cageo.2012.07.021

See Also

rmatrix, restore and reposition

Examples

earnet()

inc <- seq(0,85,5)
dec <- rep(0,length(inc))

earpoints(dec,inc)

rdec <- rep(0, length(inc))
rinc <- rep(90, length(inc))

mag <- 90
rmag  <- seq(mag, 0, by = -mag/(length(inc)-1))

rot <- rotate(dec,inc,rdec,rinc,rmag)

earpoints(dec = round(rot$dec,digits = 2), inc = round(rot$inc,digits = 2),
          l = list(bg = "green"),
          u = list(bg = "blue"),
          h = list(bg = "yellow"))

earpoints(dec = 0, inc = 90, l = list(bg = "red"))