MultiLoop III - Tutorial 3MultiLoop III - Tutorial 3

Creating a Grid & Plotting Creating a Grid & Plotting VectorsVectors

(Continued from Tutorial 2)(Continued from Tutorial 2)

Step 1: Create the gridStep 1: Create the grid

Complete Tutorial 1 and 2.Complete Tutorial 1 and 2. From the “Survey” menu, select “Edit Grids”From the “Survey” menu, select “Edit Grids” The “Define Grid” dialogue will appearThe “Define Grid” dialogue will appear Enter the properties of the grid to createEnter the properties of the grid to create Select “New”Select “New” A grid will be created.A grid will be created. Go.Go.

From the “Survey” menu, select “Edit Grids”

The “Define Grid” Dialogue appears,sensible default values will be computed.

The grid location in space

The coordinate on the grid located in space

Orientation

Length of the sides

Calculated strike and dip

DiscretizationHatching and back-planetoggles

Colouring options

Grid selector

Create a grid with the parameters given in the edit boxes to the right Replots the grid with the

parameters selected, recomputesscattered vectors

Edit the referencepoint, rotations,strike length and dip extensions to parameterize the grid you want.

…these parameters can be changed later,so don’t be tooconcerned to set themperfectly the first timethrough.

When, done, click “New” to create the grid

When a new grid is created, the “Grid Selector” will need a name for it.

A suggested name will be automatically generated.

Set the name you want and click“OK” to create the grid. Oftenthe suggested name will be goodenough, and does not need changing.

If a duplicate grid name is entered, a grid will not be created.

The new grid nameappears in the grid selector

The grid should appear in the graphic window. If it does not,check the orientation and reference point parameters to ensurethe grid is properly located. Check the strike length and dipextension to ensure the grid is the proper size.

Hint: If the grid cannot be seen, Turn on the backplane to help locate the grid. Also check the “Show” option in the “Plot” menu, to ensure that grids are showing.

Step 2: Compute scattered Step 2: Compute scattered fieldsfields

Add hatching to the gridAdd hatching to the grid Compute the scattered vector fields Compute the scattered vector fields

and view the default plotand view the default plot Remove the profile plot from viewRemove the profile plot from view Select a new channel to view as Select a new channel to view as

scattered vectorsscattered vectors GoGo

Click on “Hatching“to add hatching

Hatch marks are then shown at the discretization points

Click “Update” to update the scattered vector fields on the grid.

A confirmation message will appear to confirm thatthe scattered vectors should be recomputed.Click “Yes”

The scattered vector fields are recomputed and plotted

To work more with scattered vectors, exit the “Define Grid” dialog

To remove the profiles from thedisplay (the profiles will still exist,but will just not be shown),from the “Plot” menu, select“Show” and click on “ResponseProfiles”.

This makes the display lesscluttered, so working with thescattered vector plots is easier. This is done as a matter of convenience only.

The Response Profiles can beredisplayed at any time by repeating this operation.

The profile plots are removed; the grid with the scattered vectors is easier to see.

To edit the scattered vectors, click “Vectors”on the “Plot” menu

This brings up the “Plot Magnetic Field Vectors” dialogue

Vector DataSelector: showsexisting vectordata

Normalized or unnormalizedvectors can be plotted

The “Plot Magnetic Field Vectors” dialogue

The scale sets the size of vectors plotted

Vector plots can be createdor deleted. Here are novector data available tocreate a plot, so “CreatePlot” is grayed out.

Settings: “Auto” sets the scales and coloursautomatically

Two vectorfields can beoverlain

A 3-component(X,Y,Z) field isplotted

No field is plotted in the second selection

The vector plot can be hidden from view

The vector field for channel“Eq_0” is plotted

To change the channel plotted,click on the button in the Channelcolumn

A “Select the gate name” dialogue will appear. Select the gate name from the list box

Click “OK” when done

The vector field for the selected channel will be plotted

Step 3: Plot a second Step 3: Plot a second channelchannel

Select how the vectors will be plottedSelect how the vectors will be plotted Select the channel to plotSelect the channel to plot GoGo

To plot the second vector field,click on the Component, in thisCase “No Selection” is showing

A “Set Component” dialogue will appear. Select the component from the radio buttonlist

Click “OK” when done

As before, to change the channel plotted,click on button in the Channel column

A “Select the gate name” dialogue will appear. Select the gate name from the list box

Click “OK” when done

Two 3-component vector fields are now plotted

The vector fields compare channels UT_6 and UT_1

Detail of the vector field

To zoom in, use the magnifying glass or type “i”

Each vector field is plotted with its own colour scheme. The colourused varies with the magnitude of the vector.

Channel UT_6 is plotted in purple (large) and blue (small)

Channel UT_1 large amplitudes are plotted in red,smaller amplitudes in purple