Hindu Kush Mountains of Afghanistan

February 20, 2011

EPOD--Sheridan--two collisions (2) 

: Rob Sheridan
Summary Author: Rob Sheridan

Seen in the foreground, two medical evacuation helicopters (dust-offs) take-off from the Joint Theater Hospital at Bagram Airfield in eastern Afghanistan to a mountain rescue of a wounded Coalition soldier. The political geography of Afghanistan has been dominated by collisions between human cultures for centuries. The Hindu Kush Mountains tower over the topography of eastern Afghanistan, and represent another type of collision, albeit on a much longer timescale. This mountain range is a western extension of the Himalayas, which began forming about 70 million years ago, during the late Cretaceous Period, as the Indo-Australian Plate drove north into the Eurasian Plate, forming a convergent boundary and resulting in the ongoing Himalayan orogeny. These young mountains consist primarily of sedimentary and metamorphic rock that has been lifted and folded from the bed of the Tethys Sea. This ancient sea was closed by these plate movements during tens of millions of years of convergence. The orogeny continues today with the Indo-Australian Plate moving northward about two inches (60 mm) and the Himalayas pushing up about a fifth of an inch (5 mm) every year. The still-growing Himalayas are being simultaneously eroded by wind and melting snow, creating the fine clay soil that forms the floors of eastern Afghanistan’s fertile valleys and the tiny grains of dust that wreaks havoc with Coalition helicopter engines. 

Photo Details: Camera: Canon PowerShot SD940 IS; Focal Length: 20.0mm; Digital Zoom: 1.953x; Aperture: f/5.9; Exposure Time: 0.010 s (1/100); ISO equiv: 160.