166:
87:
819:
843:
1897:
20:
79:
590:
855:
831:
110:, used to classify volcanic rocks chemically. However, the IUGS allows the use of the term to describe rocks close to the boundary between the rhyolite and dacite fields in each classification scheme. Rhyodacite then describes a fine-grained igneous rock containing between 20% and 60%
125:
The U.S. Geological Survey defines rhyodacite as volcanic rock containing 20% to 60% quartz and with plagioclase making up 35% to 65% of the total feldspar content. This makes rhyodacite the extrusive equivalent of monzogranite.
165:
1628:
1938:
772:
90:
TAS diagram with the approximate position of rhyodacite highlighted in yellow (T=trachyte or trachydacite; R=rhyolite; O3=dacite)
893:
448:
259:
275:
Goff, Fraser; Gardner, Jamie N.; Reneau, Steven L.; Kelley, Shari A.; Kempter, Kirt A.; Lawrence, John R. (2011).
859:
1931:
346:
1972:
835:
802:
797:
316:
1924:
174:
1957:
201:
1962:
958:
926:
886:
441:
1378:
1343:
364:"Pre-eruptive magma mixing in ash-flow deposits of the Tertiary Rum Igneous Centre, Scotland"
276:
1967:
375:
288:
8:
177:. This rock floated across the Indian Ocean for almost a year before it washed ashore at
99:
379:
292:
1174:
879:
823:
767:
554:
529:
434:
399:
107:
67:
225:
205:
1134:
842:
762:
621:
559:
403:
391:
342:
255:
1912:
1826:
1538:
1325:
1194:
847:
777:
746:
741:
524:
383:
194:
186:
1638:
1398:
1251:
716:
579:
491:
481:
1908:
1831:
1673:
1266:
1189:
951:
792:
721:
539:
519:
387:
1951:
1876:
1791:
1756:
1603:
1169:
1074:
946:
787:
691:
598:
574:
549:
544:
534:
395:
254:(2nd ed.). Cambridge, UK: Cambridge University Press. pp. 139–143.
129:
In addition to its quartz and feldspar content, rhyodacite commonly contains
31:
363:
1801:
1781:
1653:
1300:
1278:
1219:
1124:
1069:
1054:
908:
782:
726:
564:
496:
178:
103:
55:
51:
362:
Troll, Valentin R.; Donaldson, Colin H.; Emeleus, C. Henry. (2004-08-01).
193:. These include extensive ash flows and fallout sheets that are important
153:
phenocrysts are less common than in rhyolite, and rhyolite has only scant
86:
1904:
1690:
1581:
1561:
1551:
1478:
1428:
1353:
1199:
1139:
1109:
1064:
1022:
995:
990:
980:
931:
676:
631:
606:
514:
486:
476:
115:
19:
122:
content. Such a rock will contain between 69% and 72% silica by weight.
1856:
1841:
1816:
1811:
1721:
1706:
1623:
1591:
1556:
1546:
1528:
1508:
1453:
1433:
1388:
1310:
1295:
1271:
1231:
1184:
1159:
1119:
1094:
1084:
1079:
1059:
968:
651:
626:
418:
British
Regional Geology: The Palaeogene Volcanic Districts of Scotland
142:
130:
185:
Like other silica-rich compositions, rhyodacites are more abundant as
1871:
1861:
1851:
1836:
1806:
1786:
1771:
1766:
1731:
1726:
1685:
1678:
1643:
1613:
1598:
1576:
1518:
1498:
1493:
1483:
1468:
1448:
1423:
1418:
1413:
1403:
1393:
1368:
1333:
1246:
1214:
1164:
1154:
1129:
1104:
1099:
1039:
1000:
963:
686:
671:
656:
504:
190:
43:
82:
QAPF diagram with the approximate location of rhyodacite highlighted
1846:
1821:
1746:
1716:
1711:
1633:
1618:
1586:
1566:
1463:
1438:
1315:
1290:
1283:
1261:
1256:
1209:
1149:
1034:
985:
975:
921:
731:
706:
681:
611:
150:
146:
134:
119:
47:
39:
78:
1866:
1796:
1761:
1736:
1668:
1503:
1443:
1383:
1348:
1241:
1089:
1049:
1017:
1012:
916:
871:
661:
646:
589:
471:
457:
277:"Geologic map of the Valles caldera, Jemez Mountains, New Mexico"
138:
1896:
1776:
1751:
1648:
1608:
1571:
1473:
1338:
1236:
1226:
1179:
1144:
1114:
1044:
1029:
1007:
941:
936:
711:
696:
666:
641:
636:
616:
569:
170:
111:
98:
guidelines, rhyodacites are not formally defined in either the
63:
35:
1741:
1663:
1658:
1523:
1488:
1408:
1363:
1358:
420:, 4th edition, Nottingham, British Geological Survey, page 77
281:
New Mexico Bureau of
Geology and Mineral Resources Map Series
154:
426:
1513:
1458:
1373:
1305:
736:
509:
95:
59:
16:
Volcanic rock rich in silica and low in alkali metal oxides
243:
274:
361:
233:
British
Geological Survey: Rock Classification Scheme
50:rocks that are intermediate in composition between
1949:
332:
330:
252:Principles of igneous and metamorphic petrology
226:"Rock Classification Scheme - Vol 1 - Igneous"
1932:
887:
442:
327:
268:
249:
250:Philpotts, Anthony R.; Ague, Jay J. (2009).
200:Rhyodacite lava flows occur in northwestern
1939:
1925:
894:
880:
449:
435:
368:Contributions to Mineralogy and Petrology
58:. Rhyodacites form from rapid cooling of
164:
85:
77:
18:
341:. Berlin: Springer-Verlag. p. 22.
118:makes up about two-thirds of the total
1950:
336:
317:"Geologic units containing rhyodacite"
311:
309:
875:
430:
1891:
830:
416:Emeleus, C.H. and Bell, B.R. (2005)
34:intermediate in composition between
23:A sample of rhyodacite from Slovakia
854:
306:
208:on the island of Eigg in Scotland.
13:
901:
14:
1984:
106:by their mineral content, or the
1895:
853:
841:
829:
818:
817:
588:
410:
355:
218:
73:
1:
456:
211:
160:
1911:. You can help Knowledge by
7:
337:Fisher, Richard V. (1984).
10:
1989:
1890:
1699:
1537:
1324:
907:
813:
755:
597:
586:
464:
388:10.1007/s00410-004-0584-0
202:Ferry County (Washington)
175:1883 eruption of Krakatoa
492:Cryptovolcanic structure
959:Basaltic trachyandesite
927:Alkali feldspar granite
773:Eruptions by death toll
182:
91:
83:
24:
1344:Banded iron formation
195:stratigraphic markers
181:, Kenya, East Africa.
173:from the late August
168:
89:
81:
22:
46:equivalent of those
380:2004CoMP..147..722T
293:2011AGUFM.V13C2606G
102:, used to classify
100:QAPF classification
68:alkali metal oxides
62:relatively rich in
1700:Specific varieties
768:Lists of volcanoes
555:Subglacial volcano
530:Pyroclastic shield
183:
108:TAS classification
92:
84:
25:
1973:Volcanology stubs
1920:
1919:
1885:
1884:
1135:Nepheline syenite
869:
868:
622:Basaltic andesite
560:Submarine volcano
339:Pyroclastic rocks
1980:
1941:
1934:
1927:
1899:
1892:
1827:Rapakivi granite
1539:Metamorphic rock
1326:Sedimentary rock
1195:Quartz monzonite
896:
889:
882:
873:
872:
857:
856:
845:
833:
832:
821:
820:
778:Decade Volcanoes
756:Lists and groups
747:Pyroclastic flow
742:Pyroclastic fall
592:
525:Pyroclastic cone
451:
444:
437:
428:
427:
421:
414:
408:
407:
359:
353:
352:
334:
325:
324:
313:
304:
303:
301:
299:
272:
266:
265:
247:
241:
240:
230:
222:
187:pyroclastic rock
1988:
1987:
1983:
1982:
1981:
1979:
1978:
1977:
1958:Aphanitic rocks
1948:
1947:
1946:
1945:
1888:
1886:
1881:
1695:
1639:Pseudotachylite
1533:
1320:
1252:Tephriphonolite
903:
900:
870:
865:
809:
751:
717:Tephriphonolite
593:
584:
580:Harmonic tremor
482:Complex volcano
460:
455:
425:
424:
415:
411:
360:
356:
349:
335:
328:
315:
314:
307:
297:
295:
273:
269:
262:
248:
244:
228:
224:
223:
219:
214:
163:
76:
17:
12:
11:
5:
1986:
1976:
1975:
1970:
1965:
1963:Volcanic rocks
1960:
1944:
1943:
1936:
1929:
1921:
1918:
1917:
1900:
1883:
1882:
1880:
1879:
1874:
1869:
1864:
1859:
1854:
1849:
1844:
1839:
1834:
1832:Rhomb porphyry
1829:
1824:
1819:
1814:
1809:
1804:
1799:
1794:
1789:
1784:
1779:
1774:
1769:
1764:
1759:
1754:
1749:
1744:
1739:
1734:
1729:
1724:
1719:
1714:
1709:
1703:
1701:
1697:
1696:
1694:
1693:
1688:
1683:
1682:
1681:
1674:Talc carbonate
1671:
1666:
1661:
1656:
1651:
1646:
1641:
1636:
1631:
1626:
1621:
1616:
1611:
1606:
1601:
1596:
1595:
1594:
1584:
1579:
1574:
1569:
1564:
1559:
1554:
1549:
1543:
1541:
1535:
1534:
1532:
1531:
1526:
1521:
1516:
1511:
1506:
1501:
1496:
1491:
1486:
1481:
1476:
1471:
1466:
1461:
1456:
1451:
1446:
1441:
1436:
1431:
1426:
1421:
1416:
1411:
1406:
1401:
1396:
1391:
1386:
1381:
1376:
1371:
1366:
1361:
1356:
1351:
1346:
1341:
1336:
1330:
1328:
1322:
1321:
1319:
1318:
1313:
1308:
1303:
1298:
1293:
1288:
1287:
1286:
1276:
1275:
1274:
1267:Trachyandesite
1264:
1259:
1254:
1249:
1244:
1239:
1234:
1229:
1224:
1223:
1222:
1217:
1207:
1202:
1197:
1192:
1190:Quartz diorite
1187:
1182:
1177:
1172:
1167:
1162:
1157:
1152:
1147:
1142:
1137:
1132:
1127:
1122:
1117:
1112:
1107:
1102:
1097:
1092:
1087:
1082:
1077:
1072:
1067:
1062:
1057:
1052:
1047:
1042:
1037:
1032:
1027:
1026:
1025:
1015:
1010:
1005:
1004:
1003:
993:
988:
983:
978:
973:
972:
971:
966:
956:
955:
954:
952:Picrite basalt
949:
939:
934:
929:
924:
919:
913:
911:
905:
904:
902:Types of rocks
899:
898:
891:
884:
876:
867:
866:
864:
863:
851:
839:
827:
814:
811:
810:
808:
807:
806:
805:
800:
793:Volcanic field
790:
785:
780:
775:
770:
765:
759:
757:
753:
752:
750:
749:
744:
739:
734:
729:
724:
722:Trachyandesite
719:
714:
709:
704:
699:
694:
689:
684:
679:
674:
669:
664:
659:
654:
649:
644:
639:
634:
629:
624:
619:
614:
609:
603:
601:
599:Volcanic rocks
595:
594:
587:
585:
583:
582:
577:
572:
567:
562:
557:
552:
547:
542:
540:Shield volcano
537:
532:
527:
522:
520:Parasitic cone
517:
512:
507:
502:
499:
494:
489:
484:
479:
474:
468:
466:
462:
461:
454:
453:
446:
439:
431:
423:
422:
409:
374:(6): 722–739.
354:
347:
326:
305:
267:
260:
242:
216:
215:
213:
210:
162:
159:
75:
72:
15:
9:
6:
4:
3:
2:
1985:
1974:
1971:
1969:
1966:
1964:
1961:
1959:
1956:
1955:
1953:
1942:
1937:
1935:
1930:
1928:
1923:
1922:
1916:
1914:
1910:
1907:article is a
1906:
1901:
1898:
1894:
1893:
1889:
1878:
1875:
1873:
1870:
1868:
1865:
1863:
1860:
1858:
1855:
1853:
1850:
1848:
1845:
1843:
1840:
1838:
1835:
1833:
1830:
1828:
1825:
1823:
1820:
1818:
1815:
1813:
1810:
1808:
1805:
1803:
1800:
1798:
1795:
1793:
1792:Litchfieldite
1790:
1788:
1785:
1783:
1780:
1778:
1775:
1773:
1770:
1768:
1765:
1763:
1760:
1758:
1757:Hyaloclastite
1755:
1753:
1750:
1748:
1745:
1743:
1740:
1738:
1735:
1733:
1730:
1728:
1725:
1723:
1720:
1718:
1715:
1713:
1710:
1708:
1705:
1704:
1702:
1698:
1692:
1689:
1687:
1684:
1680:
1677:
1676:
1675:
1672:
1670:
1667:
1665:
1662:
1660:
1657:
1655:
1652:
1650:
1647:
1645:
1642:
1640:
1637:
1635:
1632:
1630:
1627:
1625:
1622:
1620:
1617:
1615:
1612:
1610:
1607:
1605:
1604:Litchfieldite
1602:
1600:
1597:
1593:
1590:
1589:
1588:
1585:
1583:
1580:
1578:
1575:
1573:
1570:
1568:
1565:
1563:
1560:
1558:
1555:
1553:
1550:
1548:
1545:
1544:
1542:
1540:
1536:
1530:
1527:
1525:
1522:
1520:
1517:
1515:
1512:
1510:
1507:
1505:
1502:
1500:
1497:
1495:
1492:
1490:
1487:
1485:
1482:
1480:
1477:
1475:
1472:
1470:
1467:
1465:
1462:
1460:
1457:
1455:
1452:
1450:
1447:
1445:
1442:
1440:
1437:
1435:
1432:
1430:
1427:
1425:
1422:
1420:
1417:
1415:
1412:
1410:
1407:
1405:
1402:
1400:
1397:
1395:
1392:
1390:
1387:
1385:
1382:
1380:
1377:
1375:
1372:
1370:
1367:
1365:
1362:
1360:
1357:
1355:
1352:
1350:
1347:
1345:
1342:
1340:
1337:
1335:
1332:
1331:
1329:
1327:
1323:
1317:
1314:
1312:
1309:
1307:
1304:
1302:
1299:
1297:
1294:
1292:
1289:
1285:
1282:
1281:
1280:
1277:
1273:
1270:
1269:
1268:
1265:
1263:
1260:
1258:
1255:
1253:
1250:
1248:
1245:
1243:
1240:
1238:
1235:
1233:
1230:
1228:
1225:
1221:
1218:
1216:
1213:
1212:
1211:
1208:
1206:
1203:
1201:
1198:
1196:
1193:
1191:
1188:
1186:
1183:
1181:
1178:
1176:
1173:
1171:
1170:Phonotephrite
1168:
1166:
1163:
1161:
1158:
1156:
1153:
1151:
1148:
1146:
1143:
1141:
1138:
1136:
1133:
1131:
1128:
1126:
1123:
1121:
1118:
1116:
1113:
1111:
1108:
1106:
1103:
1101:
1098:
1096:
1093:
1091:
1088:
1086:
1083:
1081:
1078:
1076:
1075:Hyaloclastite
1073:
1071:
1068:
1066:
1063:
1061:
1058:
1056:
1053:
1051:
1048:
1046:
1043:
1041:
1038:
1036:
1033:
1031:
1028:
1024:
1021:
1020:
1019:
1016:
1014:
1011:
1009:
1006:
1002:
999:
998:
997:
994:
992:
989:
987:
984:
982:
979:
977:
974:
970:
967:
965:
962:
961:
960:
957:
953:
950:
948:
947:Alkali basalt
945:
944:
943:
940:
938:
935:
933:
930:
928:
925:
923:
920:
918:
915:
914:
912:
910:
906:
897:
892:
890:
885:
883:
878:
877:
874:
862:
861:
852:
850:
849:
844:
840:
838:
837:
828:
826:
825:
816:
815:
812:
804:
801:
799:
796:
795:
794:
791:
789:
788:Volcanic belt
786:
784:
781:
779:
776:
774:
771:
769:
766:
764:
761:
760:
758:
754:
748:
745:
743:
740:
738:
735:
733:
730:
728:
725:
723:
720:
718:
715:
713:
710:
708:
705:
703:
700:
698:
695:
693:
692:Phonotephrite
690:
688:
685:
683:
680:
678:
675:
673:
670:
668:
665:
663:
660:
658:
655:
653:
650:
648:
645:
643:
640:
638:
635:
633:
630:
628:
625:
623:
620:
618:
615:
613:
610:
608:
605:
604:
602:
600:
596:
591:
581:
578:
576:
575:Volcanic cone
573:
571:
568:
566:
563:
561:
558:
556:
553:
551:
550:Stratovolcano
548:
546:
545:Somma volcano
543:
541:
538:
536:
535:Rootless cone
533:
531:
528:
526:
523:
521:
518:
516:
513:
511:
508:
506:
503:
500:
498:
495:
493:
490:
488:
485:
483:
480:
478:
475:
473:
470:
469:
467:
463:
459:
452:
447:
445:
440:
438:
433:
432:
429:
419:
413:
405:
401:
397:
393:
389:
385:
381:
377:
373:
369:
365:
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310:
294:
290:
287:: V13C–2606.
286:
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261:9780521880060
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253:
246:
239:: 1–52. 1999.
238:
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203:
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180:
176:
172:
167:
158:
157:phenocrysts.
156:
152:
149:. Quartz and
148:
144:
140:
136:
132:
127:
123:
121:
117:
114:and in which
113:
109:
105:
104:igneous rocks
101:
97:
88:
80:
71:
69:
65:
61:
57:
53:
49:
45:
42:. It is the
41:
37:
33:
32:volcanic rock
29:
21:
1913:expanding it
1902:
1887:
1802:Luxullianite
1782:Lapis lazuli
1727:Blue Granite
1654:Serpentinite
1629:Metapsammite
1379:Conglomerate
1301:Trondhjemite
1279:Trachybasalt
1220:Pantellerite
1204:
1125:Monzogranite
1070:Hornblendite
1055:Granodiorite
909:Igneous rock
858:
846:
834:
822:
783:Volcanic arc
727:Trachybasalt
701:
565:Supervolcano
497:Fissure vent
417:
412:
371:
367:
357:
338:
320:
296:. Retrieved
284:
280:
270:
251:
245:
236:
232:
220:
199:
184:
128:
124:
93:
56:granodiorite
52:monzogranite
27:
26:
1968:Volcanology
1905:volcanology
1691:Whiteschist
1582:Greenschist
1562:Cataclasite
1552:Amphibolite
1479:Phosphorite
1429:Itacolumite
1354:Calcarenite
1200:Quartzolite
1140:Nephelinite
1110:Lamprophyre
1065:Harzburgite
1023:Napoleonite
996:Charnockite
991:Carbonatite
981:Blairmorite
932:Anorthosite
860:WikiProject
803:polygenetic
798:monogenetic
677:Nephelinite
632:Blairmorite
607:Agglomerate
515:Mud volcano
487:Cryovolcano
477:Cinder cone
179:Takwa Beach
169:Rhyodacite
131:phenocrysts
116:plagioclase
74:Description
66:and low in
1952:Categories
1857:Teschenite
1842:Shonkinite
1817:Pietersite
1812:Novaculite
1722:Borolanite
1707:Adamellite
1624:Metapelite
1592:Calcflinta
1557:Blueschist
1547:Anthracite
1529:Wackestone
1509:Travertine
1454:Lumachelle
1434:Jaspillite
1389:Diamictite
1311:Websterite
1296:Troctolite
1272:Benmoreite
1232:Shonkinite
1205:Rhyodacite
1185:Pyroxenite
1160:Peridotite
1120:Lherzolite
1095:Kimberlite
1085:Ignimbrite
1080:Icelandite
1060:Granophyre
969:Shoshonite
702:Rhyodacite
652:Ignimbrite
627:Benmoreite
348:3540127569
212:References
191:lava flows
161:Occurrence
143:hornblende
28:Rhyodacite
1872:Variolite
1862:Theralite
1852:Tachylite
1837:Rodingite
1807:Mangerite
1787:Larvikite
1772:Jasperoid
1767:Jadeitite
1732:Epidosite
1686:Tectonite
1679:Soapstone
1644:Quartzite
1614:Migmatite
1599:Itabirite
1577:Granulite
1519:Turbidite
1499:Sylvinite
1494:Siltstone
1484:Sandstone
1469:Oil shale
1449:Limestone
1424:Gritstone
1419:Greywacke
1414:Geyserite
1404:Evaporite
1394:Diatomite
1369:Claystone
1334:Argillite
1247:Tachylyte
1215:Comendite
1165:Phonolite
1155:Pegmatite
1130:Monzonite
1105:Lamproite
1100:Komatiite
1040:Foidolite
1001:Enderbite
964:Mugearite
687:Phonolite
672:Leucitite
657:Komatiite
505:Lava dome
501:Lava cone
458:Volcanoes
404:128532728
396:1432-0967
204:, and at
44:extrusive
1847:Taconite
1822:Pyrolite
1747:Ganister
1717:Aphanite
1712:Appinite
1634:Phyllite
1619:Mylonite
1587:Hornfels
1567:Eclogite
1464:Mudstone
1439:Laterite
1399:Dolomite
1316:Wehrlite
1291:Trachyte
1284:Hawaiite
1262:Tonalite
1257:Tephrite
1210:Rhyolite
1175:Porphyry
1150:Obsidian
1035:Essexite
986:Boninite
976:Basanite
922:Andesite
824:Category
732:Trachyte
707:Rhyolite
682:Obsidian
612:Andesite
321:usgs.gov
206:An Sgùrr
189:than as
151:sanidine
147:pyroxene
135:andesine
120:feldspar
48:plutonic
40:rhyolite
1867:Unakite
1797:Llanite
1762:Ijolite
1737:Felsite
1669:Suevite
1504:Tillite
1444:Lignite
1384:Coquina
1349:Breccia
1242:Syenite
1090:Ijolite
1050:Granite
1018:Diorite
1013:Diabase
917:Adakite
836:Commons
763:Hotspot
662:Lapilli
647:Felsite
472:Caldera
376:Bibcode
289:Bibcode
139:biotite
1777:Kenyte
1752:Gossan
1649:Schist
1609:Marble
1572:Gneiss
1474:Oolite
1339:Arkose
1237:Sovite
1227:Scoria
1180:Pumice
1145:Norite
1115:Latite
1045:Gabbro
1030:Dunite
1008:Dacite
942:Basalt
937:Aplite
848:Portal
712:Tephra
697:Pumice
667:Latite
642:Dacite
637:Cinder
617:Basalt
570:Tossol
402:
394:
345:
298:18 May
258:
171:pumice
145:, and
112:quartz
94:Under
64:silica
36:dacite
1903:This
1742:Flint
1664:Slate
1659:Skarn
1524:Varve
1489:Shale
1409:Flint
1364:Chert
1359:Chalk
465:Types
400:S2CID
229:(PDF)
155:mafic
30:is a
1909:stub
1514:Tufa
1459:Marl
1374:Coal
1306:Tuff
737:Tuff
510:Maar
392:ISSN
343:ISBN
300:2020
256:ISBN
96:IUGS
60:lava
54:and
38:and
1877:Wad
384:doi
372:147
133:of
1954::
398:.
390:.
382:.
370:.
366:.
329:^
319:.
308:^
285:79
283:.
279:.
235:.
231:.
197:.
141:,
137:,
70:.
1940:e
1933:t
1926:v
1915:.
895:e
888:t
881:v
450:e
443:t
436:v
406:.
386::
378::
351:.
323:.
302:.
291::
264:.
237:1
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
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