A block and ash flow or block-and-ash flow is a flowing mixture of volcanic ash and large (>26 cm) angular blocks commonly formed as a result of a gravitational...

of the block and ash flow deposit adjacent to Keyhole Falls include grey spherulites and lithophysae. The third and final block and ash flow deposited...

created a caldera. Ash flow tuffs and block and ash flow deposits from this explosive eruption traveled down the Ash Creek and Bluff Creek valleys that...

collapses upon itself, forming a fast-moving pyroclastic flow (known as a block-and-ash flow) that moves down the side of the mountain at tremendous speeds...

and has two summit craters—the southernmost 200 m (660 ft)-wide one has active fumaroles. The volcano also features lava flows, block and ash flows and...

Qualibou depression, contains pyroclastic flow deposits, lava flows, domes, block and ash flow deposits, and explosion craters. This depression's perimeter...

L. M.; Clayton, G.; Goodhue, R. (January 2009). "Organic block coatings in block-and-ash flow deposits at Merapi Volcano, central Java". Geological Magazine...

and Mount Vesuvius in Italy discharged blocks weighing 2-3 tons over distances of 100-200m. Block and ash flow Xenolith – Rock inside a rock with a different...

dome explosions. Gravitational collapse of a lava dome can produce a block and ash flow. A cryptodome (from the Greek κρυπτός, kryptos, "hidden, secret")...

erupted around 4,300 years ago after a charcoal overlain by thick block-and-ash flow deposits was found. The charcoal was sent to the United States for...

is a lava dome complex of Pliocene-Pleistocene age, surrounded by block and ash flow deposits. Ajusco is part of the mountain chain of volcanic origin...

circular. Lava flows are uncommon. The volcano has generated an apron of block-and-ash flow deposits especially on the western, southwestern and eastern flanks...

3600 years ago. Lava dome growth has produced block and ash flows that traveled primarily to the northeast and southeast. The snow-capped Nevado del Tolima...

southern parts are filled with block-and-ash flows from the southern calderas. The southern calderas are the Robledo and Cerro Blanco calderas, which form...

affects combustor and turbine components. Ash can accumulate and partially block fuel spray nozzles, impairing air and fuel flow fields and mixture stoichiometries...

lava flows, but Ampato has also had explosive eruptions which have deposited ash, lapilli and pumice in the surrounding landscape. One young lava flow has...

and contains larger, coarse boulders and rock fragments, while an extremely hot ash plume lofts above it because of the turbulence between the flow and...

remnant of a cluster of lava domes south of Huaynaputina. Tephra and block-and-ash flow deposits from Holocene eruptions can be found within the amphitheatre...

shape and is formed primarily by lava flows with some block and ash flows and pyroclastic flows. Lava flows are 20–50 metres (66–164 ft) thick and often...

flows were formed by ash and 70% by blocks, with larger fragments accumulating on the margins of each flow deposit. The pyroclastic flow deposits contain...

thicknesses of 150 metres (490 ft). The lava domes are accompanied by block and ash flow deposits that reach lengths of 3.5 kilometres (2.2 mi). A steep descent...

the volcano's vent. The dome may later collapse, resulting in flows of ash and hot blocks. The eruption cycle is usually completed in a few years, but...

(1.1 Ma), Red Cliff and Nevis Peak (0.98 Ma). These are mainly andesite and dacite lava domes, with associated block and ash flows, plus lahars. Nevis...

end of the Puye Formation, a geologic formation of pyroclastic and block and ash flows exposed east of the Jemez Mountains. The dwellings were carved...

A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments...

mechanism by which the ash was transported, such as fallout tuff or ash flow tuff. Reworked tuffs, formed by erosion and redeposition of ash deposits, are usually...

pyroclastic flows, and at least one occurred a year later, on May 16, 1981. As the avalanche and initial pyroclastic flow were still advancing, a huge ash column...

products associated with Pairique are the Pairique Chico block and ash flow, the Arco Jara ignimbrite and the Cerro Lucho lavas. All of these do not exceed 5...

traced beneath this volcano. The main cone is formed by dacites and block and ash flows that were later intruded by dacitic porphyries, associated with...

smallest to largest) as volcanic ash, lapilli, or volcanic blocks (or, if they exhibit evidence of having been hot and molten during emplacement, volcanic...