@@ -91,18 +91,18 @@ E.g. `angle = 45` with `ratio = 0.5` would result into NE-SW elongated crystals.
...
@@ -91,18 +91,18 @@ E.g. `angle = 45` with `ratio = 0.5` would result into NE-SW elongated crystals.
For Quartz, let's assume we have mostly roundish/quadratic grains and only a minor preferred orientation of the crystals, so that they are slightly oriented along NE-SW:
For Quartz, let's assume we have mostly roundish/quadratic grains and only a minor preferred orientation of the crystals, so that they are slightly oriented along NE-SW:
```{r p-qu}
```{r p-qu}
p1_qu = anis2D_par2A(ratio = .9, angle = 45)
p1_qu = anis_GSLIBpar2A(ratios = .9, angles = 45)
```
```
The Feldspars have a more pronounced elongated shape, also with preferred orientation along the same direction as the Quartz grains:
The Feldspars have a more pronounced elongated shape, also with preferred orientation along the same direction as the Quartz grains:
Function `anis2D_par2A` returns the Cholesky decomposition of the anisotropy matrix. So, if the anistropy of the mineral phases had been generated by this function, then we need to calculate the cross product of the matrices to obtain the anistropy matrices `A`:
Function `anis_GSLIBpar2A` returns the inverse Cholesky decomposition of the anisotropy matrix. So, if the anistropy of the mineral phases had been generated by this function, then we need to re-calculate the anistropy range matrices `A`:
```{r}
```{r}
A1_qu = tcrossprod(p1_qu)
A1_qu = as.AnisotropyRangeMatrix(p1_qu)
A2_fsp = tcrossprod(p2_fsp)
A2_fsp = as.AnisotropyRangeMatrix(p2_fsp)
```
```
This results into
This results into
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@@ -121,20 +121,26 @@ There is also the option to directly generate the anisotropy matrix.
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@@ -121,20 +121,26 @@ There is also the option to directly generate the anisotropy matrix.
In this case, the matrix can be written manually:
In this case, the matrix can be written manually:
The Biotite occurs as thin plates and has a slightly different preferred orientation then the two main minerals:
The Biotite occurs as thin plates and has a slightly different preferred orientation then the two main minerals:
For the fracture and joint systems the anisotropy is very pronounced, because they are very thin but passing through longer distances through the rock.
For the fracture and joint systems the anisotropy is very pronounced, because they are very thin but passing through longer distances through the rock.
Accordingly, the anisotropy matrix should be chosen similar to this:
Accordingly, the anisotropy matrix should be chosen similar to this: