is there any river flowing through or alongside it?
Yes, Colorado River
Introduction
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.
are the oldest rocks in the world in the grand canyon Yes, the rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old.
Yes, Colorado River. Yes, Colorado River. Yes, Colorado River
Geology of the Grand Canyon area Geology of the Grand Canyon area Geology of the Grand Canyon area
Introduction Introduction Introduction
 The new river captured the older drainage to form the ancestral Colorado River, which in turn started to form the Grand Canyon. f. The new river captured the older drainage to form the ancestral Colorado River, which in turn started to form the Grand Canyon 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.
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Geology of the Grand Canyon area [SEP] Introduction
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 starting 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 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.