pyroclastic in English
In practice pyroclastic and volcaniclastic rocks include all the products of extrusive volcanic activity except lava flows.
Use "pyroclastic" in a sentence
1. A Cinder is a pyroclastic material
2. Intrusion of a high alumina quartz tholeiite into the pyroclastic beds terminated the activity.
3. The pyroclastic shield volcano is situated in the central Sahara of northern Chad
4. This fallout, mixed with magma, mud, and steam, sent additional pyroclastic flows speeding down St. Helens' flanks.
5. In the Seeberg area (Karawanken/Austria) intermediate to acidic pyroclastic rocks of Palaeozoic age are found.
6. Petrographic Observations on Mixing of Acid and Basic Magmas: Genesis of the Dacitoïdes of the Qom-Aran Area (Central Iran) Among the Upper Eocene pyroclastic materials of the Qom-Aran area (Central Iran) there are rocks (named lava-breccias) with intermediate facies between lavas and pyroclastic rocks.
7. Pyroclastic flow deposits have become a research topic of great interest in volcanology, because they may bring the humanity devastating hazards.
8. Cherts studied from the southern Barberton greenstone belt are identified as replacement products of various pillow lavas, pyroclastic deposits, and sedimentary deposits
9. Volcanic activity in the area culminated with the formation of pyroclastic cones, blocky lava flows, and pit craters that postdate the last Cordilleran glaciation.
10. R . Schmidt ﹐ Descriptive Nomenclature & Classification of Pyroclastic Deposits & Fragments ﹐ Recomendation of IUGS Subcommision on the Systematics of Igneous Rocks ﹐ Geology ﹐ Vol.9﹐5﹐19
11. Basalts and alkali-feldspar rhyolites, associated in some places with ignimbrites, occur in volcanic bodies that are interlayered with pyroclastic and fossiliferous Upper Cretaceus sedimentary rocks.
12. Schmidt ? Descriptive Nomenclature & Classification of Pyroclastic Deposits & Fragments ? Recomendation of IUGS Subcommision on the Systematics of Igneous Rocks ? Geology ? Vol.9? 5 ? 19
13. Rock types found in the mountainous volcanic districts include rhyolites, trachytes, dacites, andesites, basaltic lavas, widespread pyroclastic formations, and associated alluvial and lacustrine deposits.
14. The relative size of glass rims coating crystals in the matrix ash provides a semi-quantitative measure of abrasion of ash grains in pyroclastic flows.
15. Major and trace element analyses reveal that the sills in the Oville-Formation, volcanic bombs, subvolcanic xenoliths and a plug within the pyroclastic rocks belong to the alkali rock series.
16. Copper mineralization occurs mainly as disseminations around and in the altered stocks, and in the form of veins and stockworks and as impregnations in the surrounding lavas and pyroclastic rocks.
17. Localities with abnormally high reflectances (>1.0%) include sites with local heat sources, such as an intrusion (Afton mine near Kamloops), a coal fire (Hat Creek), or a hot, pyroclastic flow (south of Princeton).
18. A name for pyroclastic flows which glow red in the dark is nuée Ardente (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique.
19. An earlier caldera was filled with lava flows starting from 43,000 years BP; two pyroclastic eruptions occurred later and formed the Black Sands and Brown Tuff formations, the last of which was emplaced between about 3890 BC and 800 AD.
20. Originally Stabiae was a fortified settlement in the vesuvian area. Hidden by the historical eruption of the Vesuvius 79 A.D., the ancient Stabiae is still buried under the pyroclastic materials It was built on the Varano plain nearby to the sea from where it was possible to control both the port, where the present city of Castellammare di Stabia is located, and the important road network connected to the landing � stage.
21. A variety of volcaniclastic facies are recognized on the basis of bed geometry, sedimentary structures, and textural characteristics, and include: thinly bedded tuffs and lapillistones that were deposited by fallout from vertical ash columns (some tuffs contain accretionary lapilli and hence originated from subaerial eruption columns); pillow talus deposits (hyaloclastites) resulting from the rapid quenching of lava in water; volcaniclastic turbidites representing relatively deep-water resedimented tephra; and a single massive pyroclastic flow that was emplaced during a single depositional event, and may have been derived from a Plinian eruption or series of Surtseyan eruptions.