From this video, you can see that the origin of the lake is Kinneret
and Dead Sea
- just the emerged pits filled with Water. But as these plates still move, the pit also increases. In the north one plate collides with the other and there is a fold - the mountain Hermon
As a consequence, the Dead Sea descends every year to a meter. Today it is the lowest point of the earth - more than 400 meters below sea level.
Plates on map