Question

Active Boundaries: Convergent 3) continental vs. continental

a) Spreading centers
b) Transform faults
c) Mountain building
d) Subduction zones

Answer 1

In the context of convergent plate boundaries between continental plates, mountain building occurs due to the collision and resistance to subduction. Subduction zones, unlike continental-continental collisions, involve one plate diving beneath another and are marked by a pattern of increasing earthquake depth from the coast to inland. By analyzing global maps, various tectonic boundaries can be distinguished by their seismic and volcanic activity.

Step-by-step explanation:

Convergent Plate Boundaries: Continental vs. Continental

When discussing convergent plate boundaries, particularly the interaction between two continental plates, the most associated phenomena are mountain building and continental collisions. In such convergent zones, no subduction typically occurs since both land masses have similar densities and thus resist subducting beneath each other. Instead, the collision leads to the crumpling and thrusting up of the land to form mountain ranges. Over time, these mountains can be weathered and eroded, causing the elevation to decrease. Thus, a mountain belt with lower elevations is more likely to be older due to longer exposure to erosive processes.

At subduction zones, which are different from continental-continental convergent boundaries, one typically finds a pattern of earthquakes that increase in depth from the coast to inland. Subduction zones are associated with deep earthquakes, caused by the descending oceanic plate into the mantle. These seismic patterns help define the boundaries of subducting plates.

Further analysis of global maps showing earthquake and volcano distributions can help identify the various types of tectonic boundaries. For example, transform boundaries often have shallow earthquakes and no volcanoes. Observing these features and their patterns is key to interpreting ancient and current plate tectonic boundaries.

Answer 2

Continental vs. continental convergent boundaries lead to mountain building rather than subduction, with the uplifted crust forming large mountain ranges. Deep earthquakes typically occur at subduction zones, not continental transform boundaries. Over time, mountain ranges erode with older ranges usually having lower elevations.

Step-by-step explanation:

Convergent Plate Boundaries: Continental vs. Continental:

When two continental plates converge, the result is mountain building rather than the formation of subduction zones, which are more typical in oceanic-continental or oceanic-oceanic convergences. Mountain ranges such as the Himalayas are examples of continental vs. continental convergence. This type of active boundary is characterized by the creation of large mountain ranges as the crust is forced upwards due to the collision of the two landmasses. Deep earthquakes are usually associated with subduction zones rather than continent-continent transform boundaries. As one travels from the coast to inland at subduction zones, there is a pattern of increasing earthquake depth.

This shift from shallow to deeper earthquakes correlates with the angle of the descending plate as it submerges into the mantle. Over geologic time, mountain ranges erode and their elevations diminish suggesting older ranges typically have lower elevations. When examining maps for evidence of past tectonic activity look for patterns such as linear mountain belts which can indicate ancient convergent boundaries. The recognition of these content-loaded Active Boundaries: Convergent, and the evidence of it such as the Ural Mountains, shed light on the dynamic history of Earth's lithosphere.