lecture 5a

Mexico is a large, dynamic country with a very rough and mountainous topography, featuring very little flat ground overall.
The country is situated near the junction of three major tectonic plates, particularly in its southern part:
- North American Plate: Most of Mexico sits on this plate.
- Cocos Plate: Located in the blue region.
- Caribbean Plate: Also contributes to the complex tectonic setting.
The convergence of these three plates (North American, Cocos, and Caribbean) is located just south of central Mexico, roughly south of Acapulco. This multi-plate junction significantly increases the potential for substantial earthquake activity.
A small portion of Baja California is located on the Pacific Plate, but the majority of Mexico remains on the North American Plate.

Mexico has a high potential for major earthquake activity due to its complex tectonic plate setting.
February 2017 Earthquake: A major earthquake affected the central part of Mexico, causing deaths, significant damage, and widespread devastation, with many bodies trapped in rubble from collapsed buildings.
1985 Mexico City Earthquake: This event was far more severe than the 2017 earthquake, causing enormous damage and resulting in an estimated $5,000$ deaths in Mexico City alone. The devastation was immense, with entire buildings collapsing. This horrific event is deeply remembered by the country, especially by residents of Mexico City.
Mexico City's Vulnerability:
- A significant portion of Mexico City is built on a dried-out lake bed, where the ground can undergo subsidence (sinking). Building on this former lake bed exacerbates the effects of seismic activity, making quaking even worse.
- While many newer high-rise buildings in Mexico City are designed to be earthquake-proof, a large number of older structures do not meet these standards and are more vulnerable.
Additional Hazards in Mexico City: Besides earthquakes, the city faces threats from:
- Volcanic eruptions nearby.
- Severe air quality issues.
- High elevation (over $7,000$ feet, higher than Flagstaff, Arizona), which can make breathing difficult, especially with poor air quality.
Earthquakes frequently affect the southern half of the country, not just Mexico City.

Mexico is crisscrossed by several prominent mountain ranges, collectively known as the