STEP 2: User Coordinate Systems

Known incompatibilities between Poly3D and WEB Forms

Name and Parent

	You want to:	coordinate system.
	Coord. Sys. Name:
	Parent Coord. Sys:

Position and Orientation


+ is East	+ is North	+ is upwards	relative to parent
			(in degrees)
EW-axis	NS-axis	vertical axis	relative to parent
Rotation Order

Guidelines for entering User Coordinate System Orientation:

In most cases. your coordinate system will correspond to a particular fracture. From the strike and dip of the fracture (with right-hand rule) you can use the following rotation convention:

E-W axis rotation =	0
N-S axis rotation =	dip
vertical axis rotation =	- strike
rotation order =	321

so that x1 lies along the dip direction and x2 lies along the strike of the fracture.

Go to:

	STEP 1: Constants
	STEP 3: Observation Grids
	STEP 4: Crack Creation