gr3 - Grid data into 3D cube

Name

gr3 — Grid data into 3D cube

Syntax

Description

Create a 3D grid using moving average as the default interpolator. Will default use scalar values as input to gridding.

Arguments

No arguments, the grid will have the same number of rows and columns as the last grid that set the @nrow @ncol @nlay variables. Each node is evaluated using moving average in 3D.

inc xinc yinc zinc

Create grid model grid with increments xinc, yinc and zinc . Each node is evaluated using moving average in 3D.

nx ny nz

Create a grid with nx times ny times nz grid cells. Each node is evaluated using moving average in 3D.

fill

Will try to fill the cube. Default is a snapping method for a large set of input points.

snap

Will snap the input points to the nearest node in the cube.

lat

Lateral 3d gridding. If input is f.inst. well data with stacking velocities and time values for each well. Then one can grid a 3d velocity/time depth cube.

sca

Will use scalar values as input to gridding.

poi

Will use z values as input to gridding.

ref reference_grid

Use a reference_grid in workspace to tell the layout of the result cube.

Update cube towards wells in workspace.

upd checkshot_name [check] [disk] [tensor | conic]

Update cube towards wells in workspace checkshot_name. Moving average is the default interpolator. 
check checkstart checkstop. Remove cells that has an unacceptable range within checkstart checkstop velocity. 
disk - Apply disk for temporary datasets. Used to save memory and recommended for large cube gridding. 
tensor - Update using b-spline tensor. [max radius]. Optionally use a max radius. [fac factor]. Optionally use a radius factor. 
conic - Update using conic shape. [rad radius]. Optionally use a radius value. 
two - The format of the well string is x y z two_way_travel_time.    Default if not specified is x y z one_way_travel_time
cube - The format of the well string is the same as the cube: x y time cube_velocity.

Smooth cube with gaussian filter.

smo gau [rad xradius yradius zradius]

Smooth cube with gaussian filter.
rad xradius yradius zradius - Apply radius factors in smoothing. The factors are given independently to x, y, and z directions. Smoothing is a weighted sum of grid nodes to the side of the centre, where the number of nodes used is 2 times the radius factor.

gau rad 0 0 zradius - Apply smoothing only in the z-direction

Write out the z values of the cube as inlines and crosslines to an external file.

write [lim limit_value] [xytv] [form format] inlinestart xlinestart inlinestep xlinestep filename.

Write out cube to file filename. 
lim limit_value - Apply a limit and a limit_value for the number of nodes written out to test the procedure.
xytv - The output switches inline and xline when writing x y time velocity.
form format - Format specification of the output:

format = 1 (default) : Id     inline  xline   x-utm       y-utm       time      velocity
format = 2: inline  xline   x-utm       y-utm       time      velocity
format = 3: xline   x-utm       y-utm       time      velocity
format = 0: x-utm       y-utm       time      velocity

iinlinestart xlinestart inlinestep xlinestep - Specify start and step of inlines and crosslines to be written out. 
filename - Specify file name of output.

Transform a grid or cube to a new cube.

gr3 [ins workspacename [all] ] | [fgr] | [vsum] | [edi] | [cdi] | [int] | [form]

A cube is in active data and is recalculated to a new cube. 
ins workspacename [all] - Insert values from the scalar data part in workspacename (grid, cube or polydata) into a cube in active. The all argument will insert into all neighboring cells as well.
fgr - Fill the cube in active with interpolated values for all undefined values. 
vsum - Sum the cube in active vertically. 
edi - Evaluate distance in 2d grid in active into a new 3d cube. 
cdi - Use computed distance in 3d grid for undefined. 
int - Interpolate between layers in the cube. See command object Cube generation of all layers. 
form [const a b c] [min max]. Using a formula for velocity cube gridding. Makes a time velocity cube based on a regression formula. Input is the seabed grid and the constant a, b and c that is present in the formula. The twt grid in the formula is the layers in the cube. min maxis the min and max values for the new cube.

Examples

Ex.1: Cube gridding

mak ran 11      ;# Make 11 random points
gr3 50 50 50    ;# Make a cube of 50 50 50 nodes

# Cube model gridding
z                 ;# Erase screen
win demo          ;# Get demo window (450000 460000 6450000 6460000 1000 4000)
spe bgc whi       ;# Specify background color to white
vie 2 2 1         ;# Viewport 2 x 2 and select 1
mak ran 11        ;# Make 11 random points
mak ras           ;# Make random scalar
mhi pp            ;# Move to pp
gr3 77 77 77      ;# Grid scalars into cube of dimension 77 77 77
dis               ;# Display the cube
tx2 lle col bla txt "sca" ;# Text at lower left
vie 2 con         ;# Select viewport 2 and connect to previous
mlo pp            ;# Move lo pp
gr3 poi 77 77 77  ;# Grid points into cube of dimension 77 77 77
dis               ;# Display the cube
tx2 lle col bla txt " poi" ;# Text at lower left
vie 3 con         ;# Select viewport 3 and connect to previous
mlo pp            ;# Move lo pp
gr3 poi 77 77 77  ;# Grid single points into cube of dimension 77 77 77
gr3 vsum          ;# Grid vertical sum into cube
dis               ;# Display the cube
tx2 lle col bla txt "vsum" ;# Text at lower left
vie 4 con         ;# Select viewport 4 and connect to previous
mlo pp            ;# Move lo pp
mak ran 22        ;# Make random points
grp 77 77         ;# Make a grid
gr3 77 77 77 edi  ;# Grid distance of grid into cube of dimension 77 77 77
dis               ;# Display the cube
tx2 lle col bla txt "edi" ;# Text at lower left

The above example produces this image.

Examples of cube gridding

See also

filt impl, gen - Generate grid

lim limit_value - Apply a limit and a limit_value for the number of nodes written out to test the procedure.