Title: Colorado River
Content:  created by the tilting of sedimentary rock layers along faults. This is one of the most inaccessible regions of the continental United States. Below the confluence with the Green River, its largest tributary, in Canyonlands National Park, the Colorado enters Cataract Canyon, named for its dangerous rapids, and then Glen Canyon, known for its arches and erosion-sculpted Navajo sandstone formations. Here, the San Juan River, carrying runoff from the southern slope of Colorado's San Juan Mountains, joins the Colorado from the east. The Colorado then enters northern Arizona, where since the 1960s Glen Canyon Dam near Page has flooded the Glen Canyon reach of the river, forming 
Title: Grand Canyon
Content:  system. The ancestral Colorado River responded by cutting its channel faster and deeper. The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion. Between 100,000 and 3 million years ago, volcanic activity deposited ash and lava over the area which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.
Title: Grand Canyon
Content:  The Grand Canyon (,, Bidááʼ Haʼaztʼiʼ Tsékooh,  Gran Cañón) is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is 277 mi long, up to 18 mi wide and attains a depth of over a mile (6093 ft). The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery. Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer 
Title: Geology of the Grand Canyon area
Content:  2 million years ago greatly increased excavation of the Grand Canyon, which was nearly as deep as it is now, 1.2 million years ago. Volcanic activity deposited lava over the area 1.8 million to 500,000 years ago. At least 13 lava dams blocked the Colorado River, forming lakes that were up to 2000 ft deep. The end of the last ice age and subsequent human activity has greatly reduced the ability of the Colorado River to excavate the canyon. Dams in particular have upset patterns of sediment transport and deposition. Controlled floods from Glen Canyon Dam upstream have been conducted to see if they have a restorative effect. Earthquakes and mass wasting erosive events still affect the region. 
Title: Grand Canyon
Content:  also were deposited in non–marine environments. The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5–10 thousand feet (5000 to 10000 ft) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide Orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions). Weather conditions during the ice ages also increased the amount of water in the Colorado River 
Title: Geology of the Grand Canyon area
Content:  Powell and Lake Mead. In that distance, the Colorado River drops 2000 ft and has excavated an estimated 1000 mi3 of sediment to form the canyon. This part of the river bisects the 9000 ft-high Kaibab Uplift and passes seven plateaus (the Kaibab, Kanab, and Shivwits plateaus bound the northern part of the canyon and the Coconino bounds the southern part). Each of these plateaus are bounded by north–south-trending faults and monoclines created or reactivated during the Laramide orogeny. Streams flowing into the Colorado River have since exploited these faults to excavate their own tributary canyons, such as Bright Angel Canyon.
Title: Geology of the Grand Canyon area
Content:  can handle 13200 cuft per second more flow. Controlling river flow by use of dams has diminished the river's ability to scour rocks by substantially reducing the amount of sediment it carries. Dams on the Colorado River have also changed the character of the river water. Once both muddy and warm, the river is now clear and averages a 46 °F temperature year-round. Experimental floods approaching the 48200 cuft per second level mentioned above have been carried out in 1996 and 2004 to study the effects on sediment erosion and deposition. Grand Canyon lies on the southern end of the Intermountain West seismic belt. At least 35 earthquakes larger than 3.0 on the Richter 
Title: Colorado River
Content:  oldest visible rocks on Earth, dating as long ago as 2 billion years. The 277 mi of the river that flow through the Grand Canyon are largely encompassed by Grand Canyon National Park and are known for their difficult whitewater, separated by pools that reach up to 110 ft in depth. At the lower end of Grand Canyon, the Colorado widens into Lake Mead, the largest reservoir in the continental United States, formed by Hoover Dam on the border of Arizona and Nevada. Situated southeast of metropolitan Las Vegas, the dam is an integral component for management of the Colorado River, controlling floods and storing water for 
Title: Course of the Colorado River
Content:  carries Utah State Route 95 over the river. Below here the Colorado is joined by the Dirty Devil River and begins to widen into Lake Powell, the giant reservoir formed by Glen Canyon Dam 185 mi downstream. Lake Powell, a popular houseboating destination, is surrounded by the Glen Canyon National Recreation Area and receives over 2 million visitors each year despite its remote location. Before the dam was completed in 1966 the Colorado flowed through Glen Canyon, a sandstone gorge known for its colorful and intricately sculpted rock formations. The Escalante River, a desert stream which runs through the sinuous slot canyons of Grand Staircase-Escalante National Monument, joins about two-thirds of the way down Lake Powell. The San Juan River, which 
Title: Geology of the Grand Canyon area
Content:  largely responsible for creating the Rocky Mountains to the east. In total, the Colorado Plateau was uplifted an estimated 2 mi. The adjacent Basin and Range Province to the west started to form about 18 million years ago as the result of crustal stretching. A drainage system that flowed through what is today the eastern Grand Canyon emptied into the now lower Basin and Range province. Opening of the Gulf of California around 6 million years ago enabled a large river to cut its way northeast from the gulf. The new river captured the older drainage to form the ancestral Colorado River, which in turn started to form the Grand Canyon. Wetter climates brought upon by ice ages 

Question: through what process has the colorado river created the grand canyon in the usa?
Answer: erosion.