Whiteline; Thermoclines - Garmin Fishfinder 160C Owner's Manual

Whiteline

The Fishfinder 160C can help you to determine if the bottom is
hard or soft. When the sonar soundwaves are reflected back by the
bottom, a hard bottom returns a stronger signal than a soft bottom.
A thin whiteline indicates a softer bottom while a thick whiteline
indicates a harder bottom. Normally, a red line shows the point
where water meets the bottom. This line follows the bottom contour,
along with any significant objects lying on the bottom. The unit uses
the whiteline function to make the bottom layer information easier
to distinguish.
With the Fishfinder 160C, active whiteline helps accentuate where
strong signals are located, which makes bottom type determination
easier. The example below shows the bottom return with and without
the whiteline activated.
Whiteline Hard Bottom Soft Bottom
Fishfinder 160C Owner's Manual
Whiteline Turned Off

Thermoclines

Garmin's See-Thru technology allows the Fishfinder 160C to "see"
through thermoclines and helps locate fish where they live; and fish
love thermoclines!
A rough definition of a thermocline is a break in water where the
water temperature changes faster than the water above it.
A > W T
PPENDIX HITELINE AND HERMOCLINES
Thermocline
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