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 = 2.5,
min_data = 3,
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 ifgrid
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
. IfFALSE
, overwritesmp
.- quality_weighting
Logical. If a quality weighting should be applied: Default is
TRUE
. IfFALSE
, overwritesqp
.- 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 to0
, 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()
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
References
Ziegler, M. O. and Heidbach, O. (2019). Matlab Script Stress2Grid v1.1. GFZ Data Services. doi:10.5880/wsm.2019.002
Examples
data("san_andreas")
stress2grid(san_andreas, stat = "median")
#> Simple feature collection with 609 features and 7 fields
#> Geometry type: POINT
#> Dimension: XY
#> Bounding box: xmin: -124.57 ymin: 24.33 xmax: -107.07 ymax: 39.33
#> Geodetic CRS: WGS 84
#> # A tibble: 609 × 8
#> lon lat azi sd R mdr N geometry
#> * <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <int> <POINT [°]>
#> 1 -115. 24.3 173 4 250 0.820 3 (-114.57 24.33)
#> 2 -115. 24.3 173 4 300 0.683 3 (-114.57 24.33)
#> 3 -115. 24.3 174. 1 350 0.748 6 (-114.57 24.33)
#> 4 -115. 24.3 174. 1 400 0.654 6 (-114.57 24.33)
#> 5 -115. 24.3 168 1 450 0.908 41 (-114.57 24.33)
#> 6 -115. 24.3 168. 1 500 0.896 90 (-114.57 24.33)
#> 7 -115. 24.3 168. 1 550 0.850 120 (-114.57 24.33)
#> 8 -115. 24.3 169 1 600 0.817 153 (-114.57 24.33)
#> 9 -115. 24.3 169 1 650 0.773 169 (-114.57 24.33)
#> 10 -115. 24.3 168 1 700 0.737 183 (-114.57 24.33)
#> # ℹ 599 more rows