Q. Consider the following statements regarding the regional extensions of the global Cordillera system:
1.The Alaska Range and the Brooks Range form the northernmost extensions of the North American Cordillera.
2.In Mexico, the continuous mountain backbone is represented by the Sierra Madre Occidental and the Sierra Madre Oriental.
3.The South American Cordillera forms parallel chains that terminate completely north of the Tierra del Fuego archipelago.
4.The structural system terminates at the tip of South America, showing no geological continuity with the Antarctic Peninsula.
Which of the statements given above are correct?
Answer: A
Notes:
Explanation:
- Statement 1 is correct: The North American Cordillera includes the northern sub-arctic ranges like the Brooks Range and Alaska Range within Alaska.
- Statement 2 is correct: As the cordillera moves south into Mexico, it splits into two massive flanking ranges: the Sierra Madre Occidental (west) and the Sierra Madre Oriental (east).
- Statement 3 is incorrect: The Andes do not stop north of Tierra del Fuego; they continue all the way through the parallel chains to the very southern tip of South America at Tierra del Fuego.
- Statement 4 is incorrect: Tectonically, the system does not end at South America; it continues underwater along the Scotia Arc loop before rising again as the mountain backbone of the Antarctic Peninsula.
