Αποτελέσματα Αναζήτησης
6 Νοε 2023 · Mount Shasta was primarily constructed during four major cone-building episodes that were centered on separate vents. Each of the cone-building periods produced andesite lava flows, block-and-ash flows, and mudflows originating mainly at the central vents.
- Mount Shasta
Mount Shasta began forming on the remnants of an older,...
- Mount Shasta
Mount Shasta (/ ˈ ʃ æ s t ə / SHASS-tə; Shasta: Waka-nunee-Tuki-wuki; [5] Karuk: Úytaahkoo) [6] is a potentially active [7] stratovolcano at the southern end of the Cascade Range in Siskiyou County, California. At an elevation of 14,179 ft (4,322 m), it is the second-highest peak in the Cascades and the fifth-highest in the state.
Mount Shasta erupts episodically with ten or more eruptions occurring in short (500-2,000 year) time periods separated by long intervals (3,000-5,000 years) with few or no eruptions. Evidence suggests that magma most recently erupted at the surface about 3,200 years ago.
Mount Shasta began forming on the remnants of an older, similar volcano that collapsed 300,000 to 500,000 years ago. The collapse spawned one of the largest landslides known on Earth, covering more than 440 km 2 (170 mi 2 ) of Shasta Valley to the northeast.
19 Μαΐ 2024 · It was formed 15,000 to 20,000 years ago from andesite flows and was later intruded by a hornblende dacite dome. Since the end of the last ice age, Shastina cone was built by mostly pyroxene andesite lava flows.
30 Σεπ 2024 · Mount Shasta, peak (14,162 feet [4,317 metres]) of the Cascade Range in the Shasta-Trinity National Forest, northern California, U.S. The peak lies 77 miles (124 km) north of the city of Redding. An impressive double-peaked dormant volcano, it dominates the landscape (a vast panorama of tumbled.
The extensively eroded Sargents Ridge (right of center), on the south side of Mount Shasta, is a remnant of the oldest of four major edifices that were constructed following the collapse of ancestral Mount Shasta. The Sargents Ridge cone formed during the Pleistocene, less than 250,000 years ago.
