Garmin GPSMAP 238 Sounder - Manual (Page 125)

115
Appendix I
Understanding the Chart
Thermoclines
One of the unique features offered by Garmin is See-Thru technology. See-Thru technology allows
the GPSMAP 188/188C/238 to “see” through thermoclines and helps locate fi sh where they live;
and fi sh love thermoclines! A rough defi nition of a thermocline is a break in water where the water
temperature changes faster than the water above it. Thermoclines are shown as the weakest colors (see
pg. 14)
Thermocline
188188C238 Manual Part 2.indd 115 6/30/2003, 3:33:00 PM