Fault rake
= Fault rake
{title2=$\lambda$}
The <fault rake> specifies the slip direction within a <fault plane>. With an along-strike unit <vector> $\mathbf s$ and a down-dip unit <vector> $\mathbf d$, one explicit convention is $\mathbf b/b=\cos\lambda\,\mathbf s-\sin\lambda\,\mathbf d$. Positive $90^\circ$ then denotes up-dip slip. A convention must accompany a signed <fault rake>.