reposition {StratigrapheR}

Core correction

Description

Core correction : declination and inclination are corrected for cores of given declination, inclination and rotation

Usage

reposition(dec, inc, cdec = 0, cinc = 90, crot = 0)

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).

cdec

declination of the core.

cinc

inclination of the core.

crot

rotation of the core; it is the angle of rotation around the core direction clockwise between the measurement and the actual core orientation. In others words it is the magnitude of the rotation to apply clockwise to the measured data using the core direction as an axis.

See Also

rotate and restore

Examples

# ----

d <- zeq_example

dec <- d$Dec
inc <- d$Inc

cdec <- 75
cinc <- 45
crot <- 90

par(mfrow = c(2,2))

earnet()
earpoints(dec,inc)
earpoints(0, 90, l = list(cex = 2))
earpoints(0, 90, l = list(col = "red", bg = "red"))
title("1. Laboratory projection,
      axis for rotating the specimen")

# Roll ----

roll <- reposition(dec, inc, crot = 90)

earnet()
earpoints(roll$dec,roll$inc)
earpoints(0, 90, l = list(cex = 2))
earpoints(90, 0, h = list(col = "red", bg = "pink"), double = TRUE)
title("2. Correction of the specimen rotation,
      in red the axis for tilting the specimen")

# Tilt ---

tilt <- reposition(dec, inc, cinc = cinc ,crot = crot)

earnet()
earpoints(0, cinc, l = list(cex = 2))
earpoints(tilt$dec, tilt$inc)
earpoints(0,90, l = list(col = "red", bg = "red"))
title("3. Correction of the specimen inclination,
      in red the axis for rotating the tilted specimen")

# Orient ---

orient <- reposition(dec, inc, cdec = cdec, cinc = cinc ,crot = crot)

earnet()
earpoints(cdec, cinc, l = list(cex = 2))
earpoints(orient$dec, orient$inc)
title("4. Full geographical repositioning,
      the big dot is the core orientation")

par(mfrow = c(1,1))

# ----