Sort list alphabetically: When enabled, this will cause items in the list to be sorted in alphabetical order under their appropriate categories. However, you will not be able to re-order the layers at this time.

Show Owner: When enabled, the owner of the data is displayed in brackets next to the data. This only applies to individual data items. For example the generic item Wells will not have any owner information, however an individual grid will.

Connect contour and grid if possible: When enabled, this will cause the grids and contours to be connected. That is, if the grid is turned on or off, the corresponding contour is also turned on or off, and vice versa. If you want to display a time contour with an amplitude grid, be sure to disable this option. Note that the names of the grid and horizon must be consistent. Grids and contours are considered "connected" if the base name is the same. The base name is the grid name without the "Grid" extension, and the contour name without the "Contour" extension.

Show Layer:  Use this button to toggle a layer on. A layer is shown (visible) when the box to the right is checked on. This is the same function as turning on a check box. Note: Some layer types (Contours, Grid Data, and Raster) will only allow one to be display at a time. To override this, hold down the Ctrl key and check on multiple layers.

Hide Layer: Use the button to toggle a layer off. A layer is off (not visible) when the check box is empty. This is the same function as turning off the check box.

Delete Layer:   To delete a layer, highlight the layer first and then select Delete layer or use the icon. Note: This is NOT reversible.

Layer Visibility: Open the Layer Visibilitywindow to define the scale at which the data is turned off and on.