September 16, 2014
Photographer: Menashe Davidson
Summary Author: Menashe Davidson
The photo shows a beautiful Meshushim Pool, fed by the Meshushim stream, part of the Yehudiya Forest Nature Reserve in the Golan Heights. This pool, approximately 100 ft x 65 ft (30 m x 20 m) across, lies at the foot of an upright basalt cliff made of numerous basalt columns. The columns reach a height of approximately 16 ft (5 m) and a diameter of between 12-16 in (30-40 cm). Most of the columns are hexagons but some have columns with four, five and even seven sides.
Meshushim is the Hebrew term for the form of hexagon columns. While molten lava comes into contact with air, it cools, shrinks and cracks. The rock takes the shape of a hexagon because the circumference of the hexagons is smaller than other geometric forms, so less energy is needed to form it.
A closer look at the photo reveals that the columns in the upper layers are bent. Bending occurs because the lava cools on the outside first, while the inside the column stays in a liquid form slightly longer before solidifying. The flow from the interior acts to bend the column. The direction in which the column bends shows the direction of the lava flow before it hardened.
Syrian ash trees (Olive family) and Mount Tavor oaks grow on the edge of the pool. Photo taken on November 13, 2013.
Photo details: Camera Model: NIKON D80; Focal Length: 22mm (35mm equivalent: 33mm); Aperture: f/16.0; Exposure Time: 0.0025 s (1/400); ISO equiv: 1000.