stress2grid: Spatial interpolation of SHmax

In tectonicr: Analyzing the Orientation of Maximum Horizontal Stress

Spatial interpolation of SHmax

Description

Stress field interpolation and wavelength analysis using a kernel (weighted) mean/median and standard deviation/IQR of stress data

Usage

stress2grid(
  x,
  stat = c("mean", "median"),
  grid = NULL,
  lon_range = NULL,
  lat_range = NULL,
  gridsize = 2,
  min_data = 3L,
  threshold = 25,
  arte_thres = 200,
  method_weighting = FALSE,
  quality_weighting = TRUE,
  dist_weight = c("inverse", "linear", "none"),
  idp = 1,
  qp = 1,
  mp = 1,
  dist_threshold = 0.1,
  R_range = seq(50, 1000, 50),
  ...
)

Arguments

x	sf object containing azi SHmax in degree unc (optional) Uncertainties of SHmax in degree type (optional) Methods used for the determination of the direction of SHmax
stat	whether the direction of interpolated SHmax is based on the circular mean and standard deviation ("mean", the default) or the circular median and interquartile range ("median")
grid	(optional) Point object of class sf.
lon_range, lat_range	(optional) numeric vector specifying the minimum and maximum longitudes and latitudes (ignored if grid is specified).
gridsize	numeric. Target spacing of the regular grid in decimal degree. Default is 2.5. (is ignored if grid is specified)
min_data	integer. Minimum number of data per bin. Default is 3
threshold	numeric. Threshold for deviation of direction. Default is 25
arte_thres	numeric. Maximum distance (in km) of the grid point to the next data point. Default is 200
method_weighting	logical. If a method weighting should be applied: Default is FALSE. If FALSE, overwrites mp.
quality_weighting	logical. If a quality weighting should be applied: Default is TRUE. If FALSE, overwrites qp.
dist_weight	Distance weighting method which should be used. One of "none", "linear", or "inverse" (the default).
idp, qp, mp	numeric. The weighting power of inverse distance, quality and method. Default is 1. The higher the value, the more weight it will put. When set to 0, no weighting is applied. idp is only effective if inverse distance weighting (dist_weight="inverse") is applied.
dist_threshold	numeric. Distance weight to prevent overweight of data nearby (0 to 1). Default is 0.1
R_range	numeric value or vector specifying the kernel half-width(s), i.e. the search radius (in km). Default is seq(50, 1000, 50)
...	(optional) arguments to dist_greatcircle()

Details

This is a modified version of the MATLAB script "stress2grid"

Value

sf object containing

lon,lat

longitude and latitude in degrees

azi

Mean SHmax in degree

sd

Standard deviation of SHmax in degrees

R

Search radius in km

mdr

Mean distance of datapoints per search radius

N

Number of data points in search radius

Source

https://github.com/MorZieg/Stress2Grid

References

Ziegler, M. and Heidbach, O. (2019). Matlab Script Stress2Grid v1.1. GFZ Data Services. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.5880/wsm.2019.002")}

See Also

dist_greatcircle(), PoR_stress2grid(), compact_grid(), circular_mean(), circular_median(), circular_sd()

Examples

data("san_andreas")
stress2grid(san_andreas, stat = "median")

tectonicr documentation built on Sept. 11, 2024, 6:05 p.m.