Automatically redraw during scroll: While you are scrolling, this option will cause the map to redraw everything when you move to an area not already rasterized. This option is usually best turned off. Only in small projects or on very fast systems is turning this option on a good idea.

Show seismic during scroll: Unlike "Automatically redraw", this option can usually be left on. If enabled, this will cause the lines of seismic to be drawn in the line editing color. This will give you an idea of where you are scrolling.

Scale: This allows you to change the scale for the screen by typing in a value. You can also change the map scale directly from the Extra Toolbar.

Reference Scale: This scale allows specific culture layers to have line widths scaled. For those layers that have "Use Reference Scale" turned on (see Culture Properties), the line width will scale against the reference scale. The size used will be equal to the current line width times the reference scale divided by the current scale. These lines will become thicker as you zoom in.