Absolute distance of data points from the nearest plate boundary
Arguments
- x
sf
ordata.frame
objects of the data points in geographical coordinate system- PoR
Pole of Rotation.
"data.frame"
or object of class"euler.pole"
containing the geographical coordinates of the Pole of Rotation- pb
sf
objects of the plate boundary geometries in the geographical coordinate system- tangential
Logical. Whether the plate boundary is a tangential boundary (
TRUE
) or an inward and outward boundary (FALSE
, the default).- km
Logical. Whether the distance is expressed in kilometers (
TRUE
) or in degrees (FALSE
, the default).- ...
optional arguments passed to
smoothr::densify()
Details
The distance to the plate boundary is the longitudinal or latitudinal difference between the data point and the plate boundary (along the closest latitude or longitude) for inward/outward or tangential plate boundaries, respectively.
Note
Stresses emanate from the plate boundary along great circles, small circles or loxodromes associated with the pole of rotation. Hence the emanation distance is not necessarily the shortest distance to the plate boundary, which is measured along a great circle unrelated to the pole of rotation. The differences are particularly notable when the plate boundary is kinked or for convergent and divergent plate boundaries.
References
Wdowinski, S. (1998). A theory of intraplate tectonics. Journal of Geophysical Research: Solid Earth, 103(3), 5037<U+2013>5059. http://dx.doi.org/10.1029/97JB03390
Examples
data("nuvel1")
na_pa <- subset(nuvel1, nuvel1$plate.rot == "na")
data("plates")
plate_boundary <- subset(plates, plates$pair == "na-pa")
data("san_andreas")
res <- distance_from_pb(
x = san_andreas, PoR = na_pa, pb = plate_boundary, tangential = TRUE
)
head(res)
#> [1] -2.446542 -2.751949 -2.705483 -3.162091 -4.988116 -6.358818
res.km <- distance_from_pb(
x = san_andreas, PoR = na_pa, pb = plate_boundary, tangential = TRUE, km = TRUE
)
range(res.km)
#> [1] -1025.9419 597.3071