Why in news?
Recently there is a Magnitude 7.5 earthquake in the Southern Drake Passage caused by tectonic activity in a complex boundary region where the South American Plate and Antarctic Plate interact.
The region is marked by numerous faults and fracture zones beneath the seafloor, leading to significant seismic activity.
 
Specific Factors Behind the Event

• The Drake Passage is located in a tectonically active area that opened millions of years ago due to plate divergence, resulting in prominent fault lines.
• The event's focal mechanism and position indicate it was a strike-slip earthquake, caused by horizontal movement along a fault rather than vertical displacement.
• These types of oceanic intraplate earthquakes happen when built-up tectonic stresses are released along weak zones or pre-existing faults in the plate.
• Although most large earthquakes in this region occur near mapped boundaries like the Shackleton Fracture Zone, this quake took place in an intermediate zone, consistent with a pattern of historic crustal stress.

About Drake Passage
The Drake Passage is a deep, narrow waterway between Cape Horn at the southern tip of South America and the South Shetland Islands of Antarctica, connecting the Atlantic and Pacific Oceans and serving as the shortest sea route between the two continents.

Geography and Location

• The Drake Passage spans about 800–1,000 km (500–600 miles) wide, with a depth averaging 3,400 meters and reaching up to 4,800 meters in some areas.
• It is the narrowest stretch of the Southern Ocean and forms a climatic transition zone between subpolar South America and polar Antarctica.
• Cross-section of the Drake Passage illustrating its depth profile along with surface water salinity and temperature data

Historical Significance

• The passage is named after Sir Francis Drake, but it was first traversed by Dutch navigator Willem Schouten in 1616.
• Historically, it was a critical trade route before the Panama Canal and remains infamous for its treacherous seas, with powerful currents, storms, and massive waves.
• The region is also known as "Mar de Hoces" in Spanish, referencing an earlier (1525) Spanish encounter.

Oceanography and Climate Role

• The Antarctic Circumpolar Current flows unimpeded through the passage, playing a major role in global ocean circulation and climate regulation.
• Its unique geography allows intense mixing of cold Antarctic waters and warmer northern waters, driving powerful eddies and extreme sea conditions.
• Expedition ship crossing the Drake Passage towards Antarctica.

Hazards

• The Drake Passage is notorious for rough weather, strong westerly winds, and massive, unpredictable waves, posing risks even to modern ships.

Ecological Importance

• The passage is a habitat for whales, dolphins, seabirds (including albatrosses, petrels), and penguins.
• Its mixing zone is biologically and climatically significant for the Southern Ocean ecosystem.

Navigation and Crossing

• Despite its dangers, the passage is the preferred route for ships heading to Antarctica because alternative routes (Strait of Magellan and Beagle Channel) are narrower and equally hazardous.
• Crossing is a notable challenge for explorers, scientists, and tourists heading to Antarctica today.

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