Newberry Volcano
Updated: 4 Μαΐου 2024 14:57 GMT -
shield volcano, caldera 2434 m / 7,985 ft
Όρεγκον (Καναδάς και ΗΠΑ (ηπειρωτική χώρα)), 43.72°N / -121.23°W
Current status: normal or dormant (1 out of 5)
Όρεγκον (Καναδάς και ΗΠΑ (ηπειρωτική χώρα)), 43.72°N / -121.23°W
Current status: normal or dormant (1 out of 5)
Last update: 14 Mar 2022 (small earthquakes)
Newberry volcano east of the Cascade Range in Oregon, is one of the largest volcanoes on the US mainland. It covers about 1600 km2 and contains a large caldera, Newberry Crater, that was created several 100,000 years ago by a series of devastating eruptions.
The volcano last erupted about 1300 years ago, blasting a plug of viscous lava and creating the well-known "Big Obsidian Flow."
[smaller] [larger]
Newberry volcano eruptions: 690 AD ± 100, 490 AD ± 100, 1450 BC (?), 4450 BC (?), 4690 BC ± 150, 4770 BC ± 75, 4860 BC ± 150, 4960 BC ± 100, 5070 BC ± 150, 5260 BC ± 150, 9210 BC ± 1000 (radiocarbon dated)
Latest nearby earthquakes
Ώρα | Mag. / Βάθος | Απόσταση / Τοποθεσία | |||
26 Απρ 23:15 (Los Angeles) | 0.2 4 km | 16 km δυτικά | 8 km SSE of Three Rivers, Oregon | Περ. |
Background
The low-angle basaltic to basaltic-andesite shield volcano is dotted with more than 400 cinder cones, and most of its edifice is the result of voluminous lava flows. However, Newberry volcano has also produced major explosive silicic eruptions, which formed the 6 x 8 km wide summit caldera containing two caldera lakes.The earliest eruptive products (<0.73 million years ago) (Ma) consist of a sequence of ash-flow and airfall tuffs. Caldera collapse is thought to be associated with 2 major ash flows emplaced about 0.5 and 0.3-0.5 Ma, respectively. These eruptions were preceded by the emplacement of numerous basaltic cones and vents and silicic lava domes and flows, many of which are aligned NNW and NNE parallel to regional fault zones.
A rhyolitic magma chamber has been present throughout the past 10,000 years. 6 major eruptive episodes within the past 10,000 years until about 1300 years ago have included both the eruption of basaltic lava flows from flank vents and the explosive ejection of rhyolitic pumice and pyroclastic flows and the extrusion of obsidian flows within the caldera.
---
Source: GVP Newberry volcano information