Geological and Topographical Features of Argentina

The Argentine territory is part of the South American plate, which is pushed westward by the expansive forces of the Mid-Atlantic Ridge and faces opposition from the Nazca plate, pushed eastward from the Pacific Rise.

Mountainous Regions

Puna

A large-scale arid plateau (3,500 meters above sea level). This region features furrowed hills oriented north-south, enclosing basins at the confluence of few streams. It contains loose rocks on the slopes and in salt flats, which originated from low waters, resulting in sparse vegetation.

Eastern Range

Located east of the Puna, this region features high mountains that separate narrow and steep streams from valleys with broad and gentle slopes.

Sub-Andean Sierras

Situated east of the Eastern Cordillera, these mountains reach heights between 1,500 and 2,000 meters above sea level and follow a north-south orientation. The mountains are cut by river valleys flowing toward the plain, characterized by extensive rainfall and lush vegetation.

Pampean Ranges

These take the form of blocks oriented north-south, separated by flat areas of decreasing height. These mountains exist in large groups or chains. Abundant rains feed rivers and creeks that carve grooves; where water is scarce, salt flats are generated.

Sierra Tandilia

These are low, flat, and grouped together, featuring rounded, granitic rocks.

Sierra Ventania

Comprising two main chains, these are the tallest mountains of the system, characterized by sharp ridges, jagged shapes, and steep slopes.

Precordillera

Located west of the Pampa, this range presents a series of strings with flat tops (4,000 meters above sea level) separated by narrow valleys. Vegetation is sparse, and there are many loose rock blocks.

Front Range

Higher than the Precordillera, this range formed when it collided with the mountain range, creating rigid, narrow, and tall folds. Altitudes exceed 6,000 meters, featuring permanent snow and large accumulations of rock blocks on the hillsides. The summits are rounded rather than rugged.

Patagonian Andes and Tierra del Fuego

Less extensive and lower in height than the central Andes (2,500 m), these are cut by valleys. The topography features sharp peaks and summits, sculpted by Quaternary ice ages.

Plains and Lowlands

Chaco Plain

This region features a uniform landscape without significant distinction.

Pampas Plains

Located south of the Chaco, this region is characterized by extreme horizontality. Based on climate and vegetation, it is divided into:

• Eastern Pampas: Wet and low, with almost zero slope and subject to recurring floods.
• Western Pampas: Dry and high, characterized by a scarcity of water courses.