I agree, sounds like Peaks Mode display.
Some information can be found on Honeywell's EGPWS site. Check out the site at
http://www.egpws.com/general_informa...peaks_mode.htm and the paper at
http://www.egpws.com/general_informa...tion/peaks.pdf
Note that with Peaks Mode available, the EGPWS terrain is able to show terrain even when more than 2000' below the aircraft. In this case, the only colour on the display is green. The highest peaks are painted in solid green.
On some displays where blue colour (other than cyan) is available - usually LCDs only - Peaks Mode EGPWS is able to display sea level elevation with blue colour. This feature can be pin-programmed. Nice example is this Swiss A340:
http://www.!!!!!!!!!!!!!!/open.file/425851/L/
EoD