40:
461:
119:, commonly with scattered lithic fragments. The ash is composed of glass shards and crystal fragments. Ignimbrites may be loose and unconsolidated, or lithified (solidified) rock called lapilli-tuff. Near the volcanic source, ignimbrites often contain thick accumulations of lithic blocks, and distally, many show meter-thick accumulations of rounded cobbles of pumice. Ignimbrites may be white, grey, pink, beige, brown, or black depending on their composition and density. Many pale ignimbrites are
2844:
2868:
2615:
2880:
2856:
220:
mechanisms have an effect. A vertical variation in orientation of the structures is compelling evidence against post-depositional re-mobilization being responsible for the majority of the structures, but more work needs to be carried out to discover if the majority of ignimbrites have these vertical variations in order to say which process is the most common.
291:
283:
20:
212:
273:
Sheathfolds and other rheomorphic structures may be the result of a single stage of shear. Shear possibly occurred as the density current passed over the forming deposit. Vertical variations in the orientations of sheathfolds are evidence that rheomorphism and welding can occur syn-depositionally. It
294:
Light microscope image of a welded ignimbrite, composed of eutaxitic lapilli-tuff as seen in thin section (Long dimension is several mm). The glass shards (mostly brown) sometimes become welded together when the deposit is still hot, and can be deformed by flow and compaction about crystal fragments
242:
Another model proposed is that the density current became stationary before the rheomorphic structures form. Structures such as pervasive foliation are a result of load compaction, and other structures are the result of remobilization by load and deposition on inclined topography. The tuff deposited
185:
model. Since ignimbrite is a deposit, its characteristics cannot completely represent the flow, and the deposit may only record the depositional process. Vertical chemical zonation in ignimbrites is interpreted as recording incremental changes in the deposition, and the zonation rarely correlates
219:
Rheomorphic structures are only observed in high grade ignimbrites. There are two types of rheomorphic flow; post-depositional re-mobilization, and late stage viscous flow. While there is currently debate in the field of the relative importance of either mechanism, there is agreement that both
504:
There are two lines of evidence for the relative unimportance of lithostatic load in determining the intensity of welding; lateral changes in the degree of welding irrespective of thickness and cases where the degree of welding correlates with the chemical zoning. Welding is determined by a
318:
The ash matrix typically contains varying amounts of pea- to cobble-sized rock fragments called lithic inclusions. They are mostly bits of older solidified volcanic debris entrained from conduit walls or from the land surface. More rarely, clasts are cognate material from the magma chamber.
476:
and weld at the surface of sedimentation to form a viscous fluid; this is primary welding. If during transport and deposition the temperature is low, then the particles will not agglutinate and weld, although welding may occur later if compaction or other factors reduce the minimum welding
660:, when deformation and magmatism occurred far east of the plate boundary. Additional eruptions of ignimbrite continued in Nevada until roughly 14 million years ago. Individual eruptions were often enormous, sometimes up to thousands of cubic kilometres in volume, giving them a
593:
age (280–345 million years). It had an extremely violent origin. This material built up to considerable depth and must have taken years to cool down completely. In the process the materials that made up this mixture fused together into a very tough rock of medium density.
186:
with flow unit boundaries and may occur within flow units. It has been posited that the chemical changes are recording progressive aggradation at the base of the flow from an eruption whose composition changes with time. For this to be so, the base of the flow cannot be
274:
has been disputed that the shear between the density current and the forming deposit is significant enough to cause all of the rheomorphic structures observed in ignimbrites, although the shear could be responsible for some of the structures such as imbricate fiamme.
202:
theory suggests that the ignimbrite records progressive aggradation from a sustained current and that the differences observed between ignimbrites and within an ignimbrite are the result of temporal changes to the nature of the flow that deposited it.
477:
temperature to below the temperature of the glassy particles; this is secondary welding. This secondary welding is most common and suggests that the temperature of most pyroclastic density currents is below the softening point of the particles.
409:. The chemistry of the ignimbrites, like all felsic rocks, and the resultant mineralogy of phenocryst populations within them, is related mostly to the varying contents of sodium, potassium, calcium, the lesser amounts of iron and magnesium.
194:
deposition would not occur. Instantaneously cessation of the flow would cause local compression and extension, which would be evident in the form of tension cracks and small scale thrusting, which is not seen in most ignimbrites.
1164:
Budd, David A.; Troll, Valentin R.; Deegan, Frances M.; Jolis, Ester M.; Smith, Victoria C.; Whitehouse, Martin J.; Harris, Chris; Freda, Carmela; Hilton, David R.; Halldórsson, Sæmundur A.; Bindeman, Ilya N. (2017-01-25).
190:. The instantaneous deposition of an entire body of material is not possible because displacement of the fluid is not possible instantaneously. Any displacement of the fluid would mobilize the upper part of the flow, and
396:
occurred post-eruption as part of an autogenic post-eruptive alteration in some metastable form. Thus although tridymite and cristobalite are common minerals in ignimbrites, they may not be primary magmatic minerals.
1314:
PĂ©rez, W.; Alvarado, G. E.; Gans, P. B. (2006). "The 322 ka TiribĂ Tuff: stratigraphy, geochronology and mechanisms of deposition of the largest and most recent ignimbrite in the Valle
Central, Costa Rica".
656:. The magmatism in the Basin and Range Province included a massive flare-up of ignimbrite which began about 40 million years ago and largely ended 25 million years ago: the magmatism followed the end of the
494:
Cooling during transport is negligible, so if the eruption temperature is high enough then primary welding will occur. Lateral variations in degree of welding are not a result of cooling during transport.
1042:
Branney, M. J.; Kokelaar, P. (1992). "A reappraisal of ignimbrite emplacement: progressive aggradation and changes from particulate to non-particulate flow during emplacement of high-grade ignimbrite".
621:). The west cliffs are quarried to get blocks of Hinuera Stone, the name given to welded ignimbrite used for building cladding. The stone is light grey with traces of green and is slightly porous.
239:
cooling in the last few meters. It is also theorized that transformation occurs at a boundary layer at the base of the flow and that all the materials pass through this layer during deposition.
266:
suggest post-depositional re-mobilization. This interpretation of the deposition of the Green Tuff has been disputed, suggesting that it is an ignimbrite, and structures such as imbricate
1361:
Aguilera, Emilia Y.; Sato, Ana MarĂa; LlambĂas, Eduardo; Tickyj, Hugo (2014). "Erosion
Surface and Granitic Morphology in the Sierra de Lihuel Calel, Province of La Pampa, Argentina". In
303:) which is composed of shards and fragments of volcanic glass, pumice fragments, and crystals. The crystal fragments are commonly blown apart by the explosive eruption. Most are
251:
in
California show evidence of late stage viscous flow. These tuffs have a similar chemistry and so must have undergone the same compaction process to have the same foliation.
270:, observed in the Green Tuff, were the result of late stage primary viscous flow. Similar structures observed on Gran Canaria had been interpreted as syn-depositional flow.
472:
Welding is a common form of ignimbrite alteration. There are two types of welding, primary and secondary. If the density current is sufficiently hot the particles will
1388:
334:. Intensely welded ignimbrite may have glassy zones near the base and top, called lower and upper 'vitrophyres', but central parts are microcrystalline ('lithoidal').
170:
flows of very high particle concentration. Pyroclastic flows were envisioned as being similar to debris flows, with a body undergoing laminar flow and then stopping
697:
The layering of ignimbrites is used when the stone is worked, as it sometimes splits into convenient slabs, useful for flagstones and in garden edge landscaping.
694:
Repository, a U.S. Department of Energy terminal storage facility for spent nuclear reactor and other radioactive waste, is in a deposit of ignimbrite and tuff.
1271:
Freundt, A. (1999). "Formation of high-grade ignimbrites Part II. A pyroclastic suspension current model with implications also for low-grade ignimbrites".
258:
contains rheomorphic structures which are held to be a result of post-depositional re-mobilization because at that time the Green Tuff was believed to be a
235:
were formed during laminar viscous flow as the density current comes to a halt. A change from particulate flow to a viscous fluid could cause the rapid
609:
is covered in extensive flat sheets of ignimbrite erupted from caldera volcanoes during the
Pleistocene and Holocene. The exposed ignimbrite cliffs at
1232:"Magma Mixing and Crustal Recycling Recorded in Ternary Feldspar from Compositionally Zoned Peralkaline Ignimbrite 'A', Gran Canaria, Canary Islands"
2797:
224:
691:
932:
Chapin, C. E.; Lowell, G.R. (1979). "Primary and secondary flow structures in ash-flow tuffs of the
Gribbles Run paleovalley, central Colorado".
501:
ignimbrite is most densely welded where the thickness is greatest. The correlation is not perfect, and that other factors may have an influence.
814:
Troll, Valentin R.; Emeleus, C. Henry; Nicoll, Graeme R.; Mattsson, Tobias; Ellam, Robert M.; Donaldson, Colin H.; Harris, Chris (2019-01-24).
768:
1121:
Kobberger, G.; Schmincke, H.-U. (1999). "Deposition of rheomorphic ignimbrite D (Mogán
Formation), Gran Canaria, Canary Islands, Spain".
2473:
1464:
178:
freezing occurs when the driving stress falls below a certain level. This would produce a massive unit with an inversely graded base.
2884:
953:
798:
884:
Schmincke, H.-U.; Swanson, D. A. (1967). "Laminar
Viscous Flowage Structures in Ash-Flow Tuffs from Gran Canaria, Canary Islands".
505:
combination of factors including compositional changes, volatile content, temperature, grain size population and lithic content.
1392:
322:
If sufficiently hot when deposited, the particles in an ignimbrite may weld together, and the deposit is transformed into a
491:
There is not enough variation in the composition of primary and secondary welded ignimbrites for this to be a major factor.
330:. When this happens, the pumice lapilli commonly flatten, and these appear on rock surfaces as dark lens shapes, known as
1408:
Sparks, R. S. J. (1976). "Grain size variations in ignimbrites and implications for the transport of pyroclastic flows".
174:. The flow would travel as a plug flow, with an essentially non-deforming mass travelling on a thin shear zone, and the
143:
Two main models have been proposed to explain the deposition of ignimbrites from a pyroclastic density current: the
2827:
2822:
661:
613:(Waikato) mark the edges of the ancient Waikato River course which flowed through the valley before the last major
163:
480:
The factor that determines whether an ignimbrite has primary welding, secondary welding or no welding is debated:
633:
39:
460:
990:
2911:
2466:
1517:
1497:
1457:
625:
605:, where the striking orange-brown ignimbrite cliffs form a distinctive feature of the landscape. The nearby
598:
519:
1437:
1942:
606:
312:
262:
which has no lateral transport. Similarities between the structures in the Green Tuff and ignimbrites on
1907:
629:
585:. The ignimbrite quarried in the Hunter region at locations such as Martins Creek, Brandy Hill, Seaham (
48:
2860:
526:, Argentina, various landforms typical of granites can be observed in ignimbrite. These landforms are
1417:
1324:
1280:
1178:
1130:
1052:
1016:
978:
893:
827:
543:
432:
and bury watercourses and rivers. The water from such substrates will exit the ignimbrite blanket in
665:
228:
2867:
2192:
1167:"Magma reservoir dynamics at Toba caldera, Indonesia, recorded by oxygen isotope zoning in quartz"
2848:
2792:
2579:
2554:
2459:
1738:
1450:
1340:
1296:
1146:
1103:
1068:
909:
514:
Landscapes formed by erosion in hardened ignimbrite can be remarkably similar to those formed on
244:
760:
566:
Ignimbrites occur worldwide associated with many volcanic provinces having high-silica content
2787:
2646:
2584:
1693:
1253:
1231:
1212:
1194:
949:
863:
845:
794:
764:
700:
In the Hunter region of New South Wales, ignimbrite serves as an excellent aggregate or "blue
653:
539:
523:
342:
The mineralogy of an ignimbrite is controlled primarily by the chemistry of the source magma.
1086:
Branney, M. J.; Barry, T. L.; Godchaux, M. (2004). "Sheathfolds in rheomorphic ignimbrites".
554:. In addition, just like in granite landscapes landforms in ignimbrites may be influenced by
2872:
2802:
2771:
2766:
2549:
2390:
2102:
1889:
1758:
1425:
1332:
1288:
1243:
1202:
1186:
1138:
1095:
1060:
1024:
986:
941:
901:
853:
835:
752:
719:
701:
657:
498:
232:
79:
71:
2906:
2741:
2604:
2516:
2506:
2202:
1962:
1815:
618:
582:
555:
716: – Cultural or commercial name for a number of dimension or building stone varieties
444:
tuff eruption. In the process of boiling off this water, the ignimbrite layer may become
1421:
1328:
1284:
1182:
1134:
1056:
1020:
982:
897:
831:
2817:
2746:
2564:
2544:
2395:
2237:
1830:
1753:
1429:
1207:
1166:
858:
815:
345:
The typical range of phenocrysts in ignimbrites are biotite, quartz, sanidine or other
128:
2900:
2812:
2716:
2623:
2599:
2574:
2569:
2559:
2440:
2355:
2320:
2167:
1728:
1633:
1362:
1300:
1150:
1107:
1072:
1028:
913:
753:
590:
574:
109:
63:
1344:
412:
Some rare ignimbrites are andesitic, and may even be formed from volatile saturated
2807:
2751:
2589:
2521:
2365:
2345:
2217:
1864:
1842:
1783:
1683:
1628:
1613:
1479:
1366:
969:
Ragan, D. M.; Sheridan, M. F. (1972). "Compaction of the Bishop Tuff, California".
680:
535:
531:
445:
425:
377:
362:
263:
259:
167:
101:
473:
1248:
589:) and at abandoned quarry at Raymond Terrace is a volcanic sedimentation rock of
392:. In the majority of cases, it appears that these high-temperature polymorphs of
2701:
2656:
2631:
2539:
2511:
2501:
2254:
2145:
2125:
2115:
2042:
1992:
1917:
1763:
1698:
1668:
1623:
1581:
1554:
1549:
1539:
1502:
602:
255:
248:
78:, driven by being denser than the surrounding atmosphere. New Zealand geologist
24:
840:
816:"A large explosive silicic eruption in the British Palaeogene Igneous Province"
2726:
2651:
2420:
2405:
2380:
2375:
2285:
2270:
2187:
2155:
2120:
2110:
2092:
2072:
2017:
1997:
1952:
1874:
1859:
1835:
1795:
1768:
1748:
1718:
1678:
1653:
1638:
1618:
1527:
1336:
1099:
649:
632:, massive ignimbrite deposits up to several hundred metres thick occur in the
465:
350:
304:
187:
1257:
1198:
849:
2711:
2696:
2681:
2614:
2529:
2435:
2425:
2415:
2400:
2370:
2350:
2335:
2330:
2295:
2290:
2249:
2242:
2207:
2177:
2162:
2140:
2082:
2062:
2057:
2047:
2032:
2012:
1987:
1982:
1977:
1967:
1957:
1932:
1897:
1810:
1778:
1723:
1713:
1688:
1663:
1658:
1598:
1559:
1522:
713:
669:
578:
527:
485:
441:
440:
and the like, a process which may take several years, for example after the
381:
366:
358:
308:
1216:
867:
675:
Successions of ignimbrites make up a large part of post-erosional rocks in
74:, which are a hot suspension of particles and gases flowing rapidly from a
1292:
1142:
2756:
2731:
2706:
2636:
2410:
2385:
2310:
2280:
2275:
2197:
2182:
2150:
2130:
2027:
2002:
1879:
1854:
1847:
1825:
1820:
1773:
1708:
1593:
1544:
1534:
1492:
676:
614:
497:
Lithostatic load is responsible for the intensity of welding because the
433:
354:
346:
215:
Rheomorphic flow structures in a welded ignimbrite, Isle of Lipari, Italy
124:
1438:
http://www.dnzb.govt.nz/dnzb/default.asp?Find_Quick.asp?PersonEssay=3M44
945:
722: – Clastic rocks composed solely or primarily of volcanic materials
290:
2686:
2671:
2496:
2482:
2430:
2360:
2325:
2300:
2232:
2067:
2007:
1947:
1912:
1805:
1733:
1648:
1608:
1576:
1571:
1487:
1064:
645:
610:
515:
416:, where the ignimbrite would have the geochemistry of a normal basalt.
389:
370:
282:
116:
75:
44:
19:
1190:
211:
2736:
2721:
2691:
2666:
2661:
2641:
2594:
2340:
2315:
2212:
2172:
2135:
2037:
1902:
1800:
1790:
1743:
1703:
1673:
1603:
1588:
1566:
1512:
1507:
637:
551:
547:
449:
437:
413:
393:
331:
300:
267:
120:
113:
52:
32:
28:
1007:
Wolff, J. A.; Wright, J. V. (1981). "Rheomorphism of welded tuffs".
905:
2305:
2227:
2222:
2087:
2052:
1972:
1927:
1922:
731:
586:
567:
459:
289:
281:
210:
132:
87:
38:
18:
1442:
1436:
Dictionary of New
Zealand Biography, Patrick Marshall 1869-1950,
791:
Pyroclastic
Density Currents and the Sedimentation of Ignimbrites
734: – Hot semifluid material found beneath the surface of Earth
2761:
2534:
2077:
2022:
1937:
1869:
725:
641:
429:
385:
307:
that grew in the magma, but some may be exotic crystals such as
105:
67:
2455:
1446:
759:. New York, United States: Cambridge University Press. p.
299:
Ignimbrite is primarily composed of a matrix of volcanic ash (
166:
in 1976. Sparks attributed the poor sorting in ignimbrites to
227:
in
Colorado suggests that the rheomorphic structures such as
2451:
728: – Molten rock expelled by a volcano during an eruption
223:
A model based on observations at the Wall Mountain Tuff at
376:
Commonly in most felsic ignimbrites the quartz polymorphs
1230:
Troll, Valentin R.; Schmincke, Hans-Ulrich (2002-02-01).
405:
Most ignimbrites are silicic, with generally over 65% SiO
991:
10.1130/0016-7606(1972)83[95:COTBTC]2.0.CO;2
100:
Ignimbrites are made of a very poorly sorted mixture of
448:(altered). This tends to form chimneys and pockets of
755:
Igneous Rocks: A Classification and Glossary of Terms
624:
Huge deposits of ignimbrite form large parts of the
464:
Rock sample of ignimbrite, collected at the foot of
311:, derived from other magmas, igneous rocks, or from
127:. Darker-coloured ignimbrites may be densely welded
2780:
2622:
2489:
2263:
2101:
1888:
1478:
147:deposition and the progressive aggradation models.
27:from California, United States, uncompressed with
573:Ignimbrite occurs very commonly around the lower
1391:. University of Colorado Boulder. Archived from
936:. Geological Society of America Special Papers.
704:" for road surfacing and construction purposes.
484:Different chemical compositions will lower the
1009:Journal of Volcanology and Geothermal Research
424:Large hot ignimbrites can create some form of
2467:
1458:
1371:Gondwana Landscapes in southern South America
784:
782:
780:
47:in this photo is the ignimbrite layer of the
8:
1356:
1354:
879:
877:
2474:
2460:
2452:
1465:
1451:
1443:
1247:
1206:
857:
839:
428:activity as they tend to blanket the wet
927:
925:
923:
789:Branney, M. J.; Kokelaar, B. P. (2002).
225:Florissant Fossil Beds National Monument
70:. Ignimbrites form from the deposits of
1002:
1000:
743:
570:and the resulting explosive eruptions.
1389:"The Mid-Tertiary Ignimbrite Flare-Up"
971:Geological Society of America Bulletin
7:
2855:
384:are usually found within the welded
181:There are several problems with the
162:model was proposed by volcanologist
2879:
1430:10.1111/j.1365-3091.1976.tb00045.x
14:
648:, and north-central and southern
2878:
2866:
2854:
2843:
2842:
2613:
793:. Bath: The Geological Society.
751:Le Maitre, R. W., ed. (2002).
617:eruption 1,800 years ago (the
597:Ignimbrite also occurs in the
1:
1387:Cannon, E. (April 28, 2002).
1373:. Springer. pp. 393–422.
1029:10.1016/0377-0273(81)90052-4
323:
82:(1869–1950) coined the term
2928:
1249:10.1093/petrology/43.2.243
841:10.1038/s41598-018-35855-w
662:Volcanic Explosivity Index
628:in western Mexico. In the
2838:
2611:
1337:10.1007/s00445-006-0053-x
1100:10.1007/s00445-003-0332-8
510:Morphology and occurrence
66:, consisting of hardened
31:on left; compressed with
2517:Cryptovolcanic structure
634:Basin and Range Province
488:and enable primary weld.
2798:Eruptions by death toll
1518:Basaltic trachyandesite
1498:Alkali feldspar granite
1317:Bulletin of Volcanology
1273:Bulletin of Volcanology
1123:Bulletin of Volcanology
1088:Bulletin of Volcanology
1045:Bulletin of Volcanology
626:Sierra Madre Occidental
886:The Journal of Geology
520:Sierra de Lihuel Calel
469:
328:eutaxitic lapilli-tuff
296:
287:
216:
207:Rheomorphic flow model
56:
36:
1908:Banded iron formation
1293:10.1007/s004450050251
1143:10.1007/s004450050246
630:western United States
463:
293:
286:A block of ignimbrite
285:
214:
198:An adaptation of the
49:Rattlesnake Formation
42:
22:
16:Type of volcanic rock
1236:Journal of Petrology
664:of 8, comparable to
1422:1976Sedim..23..147S
1329:2006BVol...69...25P
1285:1999BVol...60..545F
1183:2017NatSR...740624B
1135:1999BVol...60..465K
1057:1992BVol...54..504B
1021:1981JVGR...10...13W
983:1972GSAB...83...95R
946:10.1130/SPE180-p137
898:1967JG.....75..641S
832:2019NatSR...9..494T
666:Yellowstone Caldera
607:TaupĹŤ Volcanic Zone
357:and in the case of
324:'welded ignimbrite'
131:or, less commonly,
2793:Lists of volcanoes
2580:Subglacial volcano
2555:Pyroclastic shield
2264:Specific varieties
1171:Scientific Reports
1065:10.1007/BF00301396
934:GSA Special Papers
820:Scientific Reports
470:
297:
288:
254:The Green Tuff in
245:Wagontire Mountain
217:
57:
37:
2894:
2893:
2647:Basaltic andesite
2585:Submarine volcano
2449:
2448:
1694:Nepheline syenite
1395:on April 21, 2016
1191:10.1038/srep40624
770:978-0-511-06651-1
654:Snake River Plain
524:La Pampa Province
365:minerals such as
72:pyroclastic flows
2919:
2882:
2881:
2870:
2858:
2857:
2846:
2845:
2803:Decade Volcanoes
2781:Lists and groups
2772:Pyroclastic flow
2767:Pyroclastic fall
2617:
2550:Pyroclastic cone
2476:
2469:
2462:
2453:
2391:Rapakivi granite
2103:Metamorphic rock
1890:Sedimentary rock
1759:Quartz monzonite
1467:
1460:
1453:
1444:
1433:
1404:
1402:
1400:
1375:
1374:
1358:
1349:
1348:
1311:
1305:
1304:
1268:
1262:
1261:
1251:
1227:
1221:
1220:
1210:
1161:
1155:
1154:
1118:
1112:
1111:
1083:
1077:
1076:
1039:
1033:
1032:
1004:
995:
994:
966:
960:
959:
929:
918:
917:
881:
872:
871:
861:
843:
811:
805:
804:
786:
775:
774:
758:
748:
720:Pyroclastic rock
658:Laramide orogeny
135:in composition.
80:Patrick Marshall
2927:
2926:
2922:
2921:
2920:
2918:
2917:
2916:
2897:
2896:
2895:
2890:
2834:
2776:
2742:Tephriphonolite
2618:
2609:
2605:Harmonic tremor
2507:Complex volcano
2485:
2480:
2450:
2445:
2259:
2203:Pseudotachylite
2097:
1884:
1816:Tephriphonolite
1474:
1471:
1407:
1398:
1396:
1386:
1383:
1381:Further reading
1378:
1360:
1359:
1352:
1313:
1312:
1308:
1270:
1269:
1265:
1229:
1228:
1224:
1163:
1162:
1158:
1120:
1119:
1115:
1085:
1084:
1080:
1041:
1040:
1036:
1006:
1005:
998:
968:
967:
963:
956:
931:
930:
921:
883:
882:
875:
813:
812:
808:
801:
788:
787:
778:
771:
750:
749:
745:
741:
710:
689:
619:Hatepe eruption
583:New South Wales
564:
512:
458:
452:-altered rock.
422:
408:
403:
349:, occasionally
347:alkali feldspar
340:
280:
209:
156:
141:
23:Rocks from the
17:
12:
11:
5:
2925:
2923:
2915:
2914:
2912:Volcanic rocks
2909:
2899:
2898:
2892:
2891:
2889:
2888:
2876:
2864:
2852:
2839:
2836:
2835:
2833:
2832:
2831:
2830:
2825:
2818:Volcanic field
2815:
2810:
2805:
2800:
2795:
2790:
2784:
2782:
2778:
2777:
2775:
2774:
2769:
2764:
2759:
2754:
2749:
2747:Trachyandesite
2744:
2739:
2734:
2729:
2724:
2719:
2714:
2709:
2704:
2699:
2694:
2689:
2684:
2679:
2674:
2669:
2664:
2659:
2654:
2649:
2644:
2639:
2634:
2628:
2626:
2624:Volcanic rocks
2620:
2619:
2612:
2610:
2608:
2607:
2602:
2597:
2592:
2587:
2582:
2577:
2572:
2567:
2565:Shield volcano
2562:
2557:
2552:
2547:
2545:Parasitic cone
2542:
2537:
2532:
2527:
2524:
2519:
2514:
2509:
2504:
2499:
2493:
2491:
2487:
2486:
2481:
2479:
2478:
2471:
2464:
2456:
2447:
2446:
2444:
2443:
2438:
2433:
2428:
2423:
2418:
2413:
2408:
2403:
2398:
2396:Rhomb porphyry
2393:
2388:
2383:
2378:
2373:
2368:
2363:
2358:
2353:
2348:
2343:
2338:
2333:
2328:
2323:
2318:
2313:
2308:
2303:
2298:
2293:
2288:
2283:
2278:
2273:
2267:
2265:
2261:
2260:
2258:
2257:
2252:
2247:
2246:
2245:
2238:Talc carbonate
2235:
2230:
2225:
2220:
2215:
2210:
2205:
2200:
2195:
2190:
2185:
2180:
2175:
2170:
2165:
2160:
2159:
2158:
2148:
2143:
2138:
2133:
2128:
2123:
2118:
2113:
2107:
2105:
2099:
2098:
2096:
2095:
2090:
2085:
2080:
2075:
2070:
2065:
2060:
2055:
2050:
2045:
2040:
2035:
2030:
2025:
2020:
2015:
2010:
2005:
2000:
1995:
1990:
1985:
1980:
1975:
1970:
1965:
1960:
1955:
1950:
1945:
1940:
1935:
1930:
1925:
1920:
1915:
1910:
1905:
1900:
1894:
1892:
1886:
1885:
1883:
1882:
1877:
1872:
1867:
1862:
1857:
1852:
1851:
1850:
1840:
1839:
1838:
1831:Trachyandesite
1828:
1823:
1818:
1813:
1808:
1803:
1798:
1793:
1788:
1787:
1786:
1781:
1771:
1766:
1761:
1756:
1754:Quartz diorite
1751:
1746:
1741:
1736:
1731:
1726:
1721:
1716:
1711:
1706:
1701:
1696:
1691:
1686:
1681:
1676:
1671:
1666:
1661:
1656:
1651:
1646:
1641:
1636:
1631:
1626:
1621:
1616:
1611:
1606:
1601:
1596:
1591:
1586:
1585:
1584:
1574:
1569:
1564:
1563:
1562:
1552:
1547:
1542:
1537:
1532:
1531:
1530:
1525:
1515:
1510:
1505:
1500:
1495:
1490:
1484:
1482:
1476:
1475:
1473:Types of rocks
1472:
1470:
1469:
1462:
1455:
1447:
1441:
1440:
1434:
1416:(2): 147–188.
1405:
1382:
1379:
1377:
1376:
1363:Rabassa, Jorge
1350:
1306:
1279:(7): 545–567.
1263:
1242:(2): 243–270.
1222:
1156:
1129:(6): 465–485.
1113:
1094:(6): 485–491.
1078:
1051:(6): 504–520.
1034:
1015:(1–3): 13–34.
996:
961:
954:
919:
906:10.1086/627292
892:(6): 641–644.
873:
806:
799:
776:
769:
742:
740:
737:
736:
735:
729:
723:
717:
709:
706:
692:Yucca Mountain
688:
685:
563:
560:
516:granitic rocks
511:
508:
507:
506:
502:
495:
492:
489:
457:
454:
421:
418:
406:
402:
399:
339:
336:
279:
276:
247:in Oregon and
208:
205:
164:Stephen Sparks
155:
149:
140:
137:
129:volcanic glass
15:
13:
10:
9:
6:
4:
3:
2:
2924:
2913:
2910:
2908:
2905:
2904:
2902:
2887:
2886:
2877:
2875:
2874:
2869:
2865:
2863:
2862:
2853:
2851:
2850:
2841:
2840:
2837:
2829:
2826:
2824:
2821:
2820:
2819:
2816:
2814:
2813:Volcanic belt
2811:
2809:
2806:
2804:
2801:
2799:
2796:
2794:
2791:
2789:
2786:
2785:
2783:
2779:
2773:
2770:
2768:
2765:
2763:
2760:
2758:
2755:
2753:
2750:
2748:
2745:
2743:
2740:
2738:
2735:
2733:
2730:
2728:
2725:
2723:
2720:
2718:
2717:Phonotephrite
2715:
2713:
2710:
2708:
2705:
2703:
2700:
2698:
2695:
2693:
2690:
2688:
2685:
2683:
2680:
2678:
2675:
2673:
2670:
2668:
2665:
2663:
2660:
2658:
2655:
2653:
2650:
2648:
2645:
2643:
2640:
2638:
2635:
2633:
2630:
2629:
2627:
2625:
2621:
2616:
2606:
2603:
2601:
2600:Volcanic cone
2598:
2596:
2593:
2591:
2588:
2586:
2583:
2581:
2578:
2576:
2575:Stratovolcano
2573:
2571:
2570:Somma volcano
2568:
2566:
2563:
2561:
2560:Rootless cone
2558:
2556:
2553:
2551:
2548:
2546:
2543:
2541:
2538:
2536:
2533:
2531:
2528:
2525:
2523:
2520:
2518:
2515:
2513:
2510:
2508:
2505:
2503:
2500:
2498:
2495:
2494:
2492:
2488:
2484:
2477:
2472:
2470:
2465:
2463:
2458:
2457:
2454:
2442:
2439:
2437:
2434:
2432:
2429:
2427:
2424:
2422:
2419:
2417:
2414:
2412:
2409:
2407:
2404:
2402:
2399:
2397:
2394:
2392:
2389:
2387:
2384:
2382:
2379:
2377:
2374:
2372:
2369:
2367:
2364:
2362:
2359:
2357:
2356:Litchfieldite
2354:
2352:
2349:
2347:
2344:
2342:
2339:
2337:
2334:
2332:
2329:
2327:
2324:
2322:
2321:Hyaloclastite
2319:
2317:
2314:
2312:
2309:
2307:
2304:
2302:
2299:
2297:
2294:
2292:
2289:
2287:
2284:
2282:
2279:
2277:
2274:
2272:
2269:
2268:
2266:
2262:
2256:
2253:
2251:
2248:
2244:
2241:
2240:
2239:
2236:
2234:
2231:
2229:
2226:
2224:
2221:
2219:
2216:
2214:
2211:
2209:
2206:
2204:
2201:
2199:
2196:
2194:
2191:
2189:
2186:
2184:
2181:
2179:
2176:
2174:
2171:
2169:
2168:Litchfieldite
2166:
2164:
2161:
2157:
2154:
2153:
2152:
2149:
2147:
2144:
2142:
2139:
2137:
2134:
2132:
2129:
2127:
2124:
2122:
2119:
2117:
2114:
2112:
2109:
2108:
2106:
2104:
2100:
2094:
2091:
2089:
2086:
2084:
2081:
2079:
2076:
2074:
2071:
2069:
2066:
2064:
2061:
2059:
2056:
2054:
2051:
2049:
2046:
2044:
2041:
2039:
2036:
2034:
2031:
2029:
2026:
2024:
2021:
2019:
2016:
2014:
2011:
2009:
2006:
2004:
2001:
1999:
1996:
1994:
1991:
1989:
1986:
1984:
1981:
1979:
1976:
1974:
1971:
1969:
1966:
1964:
1961:
1959:
1956:
1954:
1951:
1949:
1946:
1944:
1941:
1939:
1936:
1934:
1931:
1929:
1926:
1924:
1921:
1919:
1916:
1914:
1911:
1909:
1906:
1904:
1901:
1899:
1896:
1895:
1893:
1891:
1887:
1881:
1878:
1876:
1873:
1871:
1868:
1866:
1863:
1861:
1858:
1856:
1853:
1849:
1846:
1845:
1844:
1841:
1837:
1834:
1833:
1832:
1829:
1827:
1824:
1822:
1819:
1817:
1814:
1812:
1809:
1807:
1804:
1802:
1799:
1797:
1794:
1792:
1789:
1785:
1782:
1780:
1777:
1776:
1775:
1772:
1770:
1767:
1765:
1762:
1760:
1757:
1755:
1752:
1750:
1747:
1745:
1742:
1740:
1737:
1735:
1732:
1730:
1729:Phonotephrite
1727:
1725:
1722:
1720:
1717:
1715:
1712:
1710:
1707:
1705:
1702:
1700:
1697:
1695:
1692:
1690:
1687:
1685:
1682:
1680:
1677:
1675:
1672:
1670:
1667:
1665:
1662:
1660:
1657:
1655:
1652:
1650:
1647:
1645:
1642:
1640:
1637:
1635:
1634:Hyaloclastite
1632:
1630:
1627:
1625:
1622:
1620:
1617:
1615:
1612:
1610:
1607:
1605:
1602:
1600:
1597:
1595:
1592:
1590:
1587:
1583:
1580:
1579:
1578:
1575:
1573:
1570:
1568:
1565:
1561:
1558:
1557:
1556:
1553:
1551:
1548:
1546:
1543:
1541:
1538:
1536:
1533:
1529:
1526:
1524:
1521:
1520:
1519:
1516:
1514:
1511:
1509:
1506:
1504:
1501:
1499:
1496:
1494:
1491:
1489:
1486:
1485:
1483:
1481:
1477:
1468:
1463:
1461:
1456:
1454:
1449:
1448:
1445:
1439:
1435:
1431:
1427:
1423:
1419:
1415:
1411:
1410:Sedimentology
1406:
1394:
1390:
1385:
1384:
1380:
1372:
1368:
1367:Ollier, Cliff
1364:
1357:
1355:
1351:
1346:
1342:
1338:
1334:
1330:
1326:
1322:
1318:
1310:
1307:
1302:
1298:
1294:
1290:
1286:
1282:
1278:
1274:
1267:
1264:
1259:
1255:
1250:
1245:
1241:
1237:
1233:
1226:
1223:
1218:
1214:
1209:
1204:
1200:
1196:
1192:
1188:
1184:
1180:
1176:
1172:
1168:
1160:
1157:
1152:
1148:
1144:
1140:
1136:
1132:
1128:
1124:
1117:
1114:
1109:
1105:
1101:
1097:
1093:
1089:
1082:
1079:
1074:
1070:
1066:
1062:
1058:
1054:
1050:
1046:
1038:
1035:
1030:
1026:
1022:
1018:
1014:
1010:
1003:
1001:
997:
992:
988:
984:
980:
977:(1): 95–106.
976:
972:
965:
962:
957:
955:0-8137-2180-6
951:
947:
943:
939:
935:
928:
926:
924:
920:
915:
911:
907:
903:
899:
895:
891:
887:
880:
878:
874:
869:
865:
860:
855:
851:
847:
842:
837:
833:
829:
825:
821:
817:
810:
807:
802:
800:1-86239-097-5
796:
792:
785:
783:
781:
777:
772:
766:
762:
757:
756:
747:
744:
738:
733:
730:
727:
724:
721:
718:
715:
712:
711:
707:
705:
703:
698:
695:
693:
686:
684:
682:
678:
673:
671:
667:
663:
659:
655:
651:
647:
643:
639:
636:, largely in
635:
631:
627:
622:
620:
616:
612:
608:
604:
600:
595:
592:
591:Carboniferous
588:
584:
580:
576:
575:Hunter Region
571:
569:
561:
559:
557:
556:joint systems
553:
549:
545:
541:
537:
533:
532:flared slopes
529:
525:
521:
517:
509:
503:
500:
496:
493:
490:
487:
483:
482:
481:
478:
475:
467:
462:
455:
453:
451:
447:
446:metasomatised
443:
439:
435:
431:
427:
419:
417:
415:
410:
400:
398:
395:
391:
387:
383:
379:
374:
372:
368:
364:
360:
356:
352:
348:
343:
337:
335:
333:
329:
325:
320:
316:
314:
310:
306:
302:
292:
284:
277:
275:
271:
269:
265:
261:
257:
252:
250:
246:
240:
238:
234:
230:
226:
221:
213:
206:
204:
201:
196:
193:
189:
184:
179:
177:
173:
169:
165:
161:
153:
150:
148:
146:
138:
136:
134:
130:
126:
122:
118:
115:
111:
107:
103:
98:
96:
92:
89:
85:
81:
77:
73:
69:
65:
64:volcanic rock
62:is a type of
61:
54:
50:
46:
41:
34:
30:
26:
21:
2883:
2871:
2859:
2847:
2808:Volcanic arc
2752:Trachybasalt
2676:
2590:Supervolcano
2522:Fissure vent
2366:Luxullianite
2346:Lapis lazuli
2291:Blue Granite
2218:Serpentinite
2193:Metapsammite
1943:Conglomerate
1865:Trondhjemite
1843:Trachybasalt
1784:Pantellerite
1684:Monzogranite
1643:
1629:Hornblendite
1614:Granodiorite
1480:Igneous rock
1413:
1409:
1397:. Retrieved
1393:the original
1370:
1323:(1): 25–40.
1320:
1316:
1309:
1276:
1272:
1266:
1239:
1235:
1225:
1177:(1): 40624.
1174:
1170:
1159:
1126:
1122:
1116:
1091:
1087:
1081:
1048:
1044:
1037:
1012:
1008:
974:
970:
964:
937:
933:
889:
885:
823:
819:
809:
790:
754:
746:
699:
696:
690:
681:Gran Canaria
674:
623:
596:
572:
565:
562:Distribution
513:
479:
471:
426:hydrothermal
423:
411:
404:
401:Geochemistry
378:cristobalite
375:
363:feldspathoid
344:
341:
327:
321:
317:
313:country rock
298:
272:
264:Gran Canaria
260:fall deposit
253:
241:
236:
222:
218:
199:
197:
191:
182:
180:
175:
171:
159:
157:
151:
144:
142:
102:volcanic ash
99:
94:
90:
83:
59:
58:
2885:WikiProject
2828:polygenetic
2823:monogenetic
2702:Nephelinite
2657:Blairmorite
2632:Agglomerate
2540:Mud volcano
2512:Cryovolcano
2502:Cinder cone
2255:Whiteschist
2146:Greenschist
2126:Cataclasite
2116:Amphibolite
2043:Phosphorite
1993:Itacolumite
1918:Calcarenite
1764:Quartzolite
1699:Nephelinite
1669:Lamprophyre
1624:Harzburgite
1582:Napoleonite
1555:Charnockite
1550:Carbonatite
1540:Blairmorite
1503:Anorthosite
940:: 137–154.
672:eruptions.
644:, southern
603:New Zealand
474:agglutinate
468:in Ethiopia
361:tuffs, the
305:phenocrysts
256:Pantelleria
249:Bishop Tuff
25:Bishop tuff
2901:Categories
2727:Rhyodacite
2677:Ignimbrite
2652:Benmoreite
2421:Teschenite
2406:Shonkinite
2381:Pietersite
2376:Novaculite
2286:Borolanite
2271:Adamellite
2188:Metapelite
2156:Calcflinta
2121:Blueschist
2111:Anthracite
2093:Wackestone
2073:Travertine
2018:Lumachelle
1998:Jaspillite
1953:Diamictite
1875:Websterite
1860:Troctolite
1836:Benmoreite
1796:Shonkinite
1769:Rhyodacite
1749:Pyroxenite
1719:Peridotite
1679:Lherzolite
1654:Kimberlite
1644:Ignimbrite
1639:Icelandite
1619:Granophyre
1528:Shoshonite
1399:August 24,
826:(1): 494.
739:References
652:, and the
650:New Mexico
640:, western
601:region of
599:Coromandel
579:Australian
528:inselbergs
466:Mount Guna
420:Alteration
351:hornblende
338:Mineralogy
326:, made of
309:xenocrysts
233:pyroclasts
139:Deposition
84:ignimbrite
60:Ignimbrite
2712:Phonolite
2697:Leucitite
2682:Komatiite
2530:Lava dome
2526:Lava cone
2483:Volcanoes
2436:Variolite
2426:Theralite
2416:Tachylite
2401:Rodingite
2371:Mangerite
2351:Larvikite
2336:Jasperoid
2331:Jadeitite
2296:Epidosite
2250:Tectonite
2243:Soapstone
2208:Quartzite
2178:Migmatite
2163:Itabirite
2141:Granulite
2083:Turbidite
2063:Sylvinite
2058:Siltstone
2048:Sandstone
2033:Oil shale
2013:Limestone
1988:Gritstone
1983:Greywacke
1978:Geyserite
1968:Evaporite
1958:Diatomite
1933:Claystone
1898:Argillite
1811:Tachylyte
1779:Comendite
1724:Phonolite
1714:Pegmatite
1689:Monzonite
1664:Lamproite
1659:Komatiite
1599:Foidolite
1560:Enderbite
1523:Mugearite
1301:128562387
1258:0022-3530
1199:2045-2322
1151:128674265
1108:130797592
1073:129177112
914:128752517
850:2045-2322
714:Bluestone
683:islands.
670:Lake Toba
581:state of
486:viscosity
442:Novarupta
434:fumaroles
382:tridymite
367:nepheline
359:phonolite
353:, rarely
278:Petrology
229:foliation
188:turbulent
125:rhyolitic
110:lithified
86:from the
2849:Category
2757:Trachyte
2732:Rhyolite
2707:Obsidian
2637:Andesite
2411:Taconite
2386:Pyrolite
2311:Ganister
2281:Aphanite
2276:Appinite
2198:Phyllite
2183:Mylonite
2151:Hornfels
2131:Eclogite
2028:Mudstone
2003:Laterite
1963:Dolomite
1880:Wehrlite
1855:Trachyte
1848:Hawaiite
1826:Tonalite
1821:Tephrite
1774:Rhyolite
1739:Porphyry
1709:Obsidian
1594:Essexite
1545:Boninite
1535:Basanite
1493:Andesite
1369:(eds.).
1345:58892024
1217:28120860
868:30679443
708:See also
677:Tenerife
390:breccias
355:pyroxene
295:(clear).
237:en masse
200:en masse
192:en masse
183:en masse
176:en masse
172:en masse
160:en masse
152:En masse
145:en masse
35:on right
2861:Commons
2788:Hotspot
2687:Lapilli
2672:Felsite
2497:Caldera
2431:Unakite
2361:Llanite
2326:Ijolite
2301:Felsite
2233:Suevite
2068:Tillite
2008:Lignite
1948:Coquina
1913:Breccia
1806:Syenite
1734:Picrite
1649:Ijolite
1609:Granite
1577:Diorite
1572:Diabase
1488:Adakite
1418:Bibcode
1325:Bibcode
1281:Bibcode
1208:5264179
1179:Bibcode
1131:Bibcode
1053:Bibcode
1017:Bibcode
979:Bibcode
894:Bibcode
859:6345756
828:Bibcode
646:Arizona
611:Hinuera
577:of the
552:gnammas
548:tafonis
540:nubbins
456:Welding
438:geysers
371:leucite
168:laminar
121:dacitic
117:lapilli
76:volcano
45:caprock
2907:Tephra
2873:Portal
2737:Tephra
2722:Pumice
2692:Latite
2667:Dacite
2662:Cinder
2642:Basalt
2595:Tossol
2341:Kenyte
2316:Gossan
2213:Schist
2173:Marble
2136:Gneiss
2038:Oolite
1903:Arkose
1801:Sovite
1791:Scoria
1744:Pumice
1704:Norite
1674:Latite
1604:Gabbro
1589:Dunite
1567:Dacite
1513:Basalt
1508:Aplite
1343:
1299:
1256:
1215:
1205:
1197:
1149:
1106:
1071:
952:
912:
866:
856:
848:
797:
767:
638:Nevada
499:Tiribi
450:kaolin
414:basalt
394:quartz
332:fiamme
301:tephra
268:fiamme
114:pumice
112:) and
95:imbri-
53:Oregon
33:fiamme
29:pumice
2490:Types
2306:Flint
2228:Slate
2223:Skarn
2088:Varve
2053:Shale
1973:Flint
1928:Chert
1923:Chalk
1341:S2CID
1297:S2CID
1147:S2CID
1104:S2CID
1069:S2CID
910:S2CID
732:Magma
702:metal
615:TaupĹŤ
587:Boral
568:magma
536:domes
518:. In
386:tuffs
154:model
133:mafic
108:when
91:igni-
88:Latin
2762:Tuff
2535:Maar
2078:Tufa
2023:Marl
1938:Coal
1870:Tuff
1401:2016
1254:ISSN
1213:PMID
1195:ISSN
950:ISBN
864:PMID
846:ISSN
795:ISBN
765:ISBN
726:Lava
679:and
668:and
642:Utah
550:and
544:tors
430:soil
388:and
380:and
369:and
231:and
158:The
106:tuff
104:(or
93:and
68:tuff
43:The
2441:Wad
1426:doi
1333:doi
1289:doi
1244:doi
1203:PMC
1187:doi
1139:doi
1096:doi
1061:doi
1025:doi
987:doi
942:doi
938:180
902:doi
854:PMC
836:doi
687:Use
243:at
123:or
51:in
2903::
1424:.
1414:23
1412:.
1365:;
1353:^
1339:.
1331:.
1321:69
1319:.
1295:.
1287:.
1277:60
1275:.
1252:.
1240:43
1238:.
1234:.
1211:.
1201:.
1193:.
1185:.
1173:.
1169:.
1145:.
1137:.
1127:60
1125:.
1102:.
1092:66
1090:.
1067:.
1059:.
1049:54
1047:.
1023:.
1013:10
1011:.
999:^
985:.
975:83
973:.
948:.
922:^
908:.
900:.
890:75
888:.
876:^
862:.
852:.
844:.
834:.
822:.
818:.
779:^
763:.
761:92
558:.
546:,
542:,
538:,
534:,
530:,
522:,
436:,
373:.
315:.
97:.
2475:e
2468:t
2461:v
1466:e
1459:t
1452:v
1432:.
1428::
1420::
1403:.
1347:.
1335::
1327::
1303:.
1291::
1283::
1260:.
1246::
1219:.
1189::
1181::
1175:7
1153:.
1141::
1133::
1110:.
1098::
1075:.
1063::
1055::
1031:.
1027::
1019::
993:.
989::
981::
958:.
944::
916:.
904::
896::
870:.
838::
830::
824:9
803:.
773:.
407:2
55:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
