| Gallipoli and Dardanelles Strait, Turkey: The city of
Gallipoli (Gelibolu in Turkish) sits at a crossroads between the
Marmara and Aegean Seas, connected by the Dardanelles Strait. The
strait is a 61-kilometer-long drowned valley formed along a fault
(fracture in Earth’s crust). The fracture formed as the Arabian,
Indian, and African tectonic plates collided with the Eurasian plate
during the Tertiary period, approximately 2-65 million years ago.
This faulting created the rugged terrain of western Turkey visible in
the lower half of this astronaut photograph, as well as the great
mountain ranges of the Alps and Himalayas. Plate collision continues
today as Turkey moves westward in relation to Eurasia. The movement
leads to frequent strike-slip earthquakes (quakes in which the
relative ground motion along the fault is forward or backward, rather
than up or down.) The urbanized area of modern Gallipoli is
visible as a light gray to pink region at the entrance to the
Dardanelles Strait. Water in the Strait flows in both northeast and
southwest directions due to opposite surface and undercurrents. The
Strait has a long history of strategic importance as it provides a
conduit between the Mediterranean and Black Seas, as well as access
to Ankara, Turkey’s capital, to the northeast (not shown). Several
ships are visible in the Strait to the southwest of Gallipoli (image
center left). The Battle of Gallipoli—part of an Allied plan to
capture Istanbul, then the capital of the Ottoman Empire—was fought
near the city during World War I. |
