811:
1034:; it decays to xenon-129, a stable isotope of xenon which appears in excess relative to other xenon isotopes. It is found in meteorites that condensed from the primordial Solar System dust cloud and trapped primordial iodine-129 (half life 15.7 million years) sometime in a relative short period (probably less than 20 million years) between the iodine-129's creation in a supernova, and the formation of the Solar System by condensation of this dust. The trapped iodine-129 now appears as a relative excess of xenon-129. Iodine-129 was the first extinct radionuclide to be inferred, in 1960. Others are
824:
39:
1011:. The global supply of helium (which occurs in gas wells as well as the atmosphere) is mainly (about 90%–99%) radiogenic, as shown by its factor of 10 to 100 times enrichment in radiogenic helium-4 relative to the primordial ratio of helium-4 to helium-3. This latter ratio is known from extraterrestrial sources, such as some
961:. Specifically, Pb is formed from U, Pb from U, and Pb from Th. In rocks that contain uranium and thorium, the excess amounts of the three heavier lead isotopes allows the rocks to be "dated", thus providing a time estimate for when the rock solidified and the mineral held the ratio of isotopes fixed and in place.
927:
Some naturally occurring isotopes are entirely radiogenic, but all those are radioactive isotopes, with half-lives too short to have occurred primordially and still exist today. Thus, they are only present as radiogenic daughters of either ongoing decay processes, or else cosmogenic (cosmic ray
1018:
As noted in the case of lead-204, a radiogenic nuclide is often not radioactive. In this case, if its precursor nuclide has a half-life too short to have survived from primordial times, then the parent nuclide will be gone, and known now entirely by a relative excess of its stable daughter. In
1002:
are stable, and small amounts were trapped in the crust of the Earth as it formed. Helium-3 is almost entirely primordial (a small amount is formed by natural nuclear reactions in the crust). Helium-3 can also be produced as the decay product of
994:, both of which form during the decay of heavier elements in bedrock. Radon is entirely radiogenic, since it has too short a half-life to have occurred primordially. Helium, however, occurs in the crust of the Earth primordially, since both
939:, a primordial fraction is always present, since all sufficiently long-lived and stable isotopes do in fact naturally occur primordially. An additional fraction of some of these isotopes may also occur radiogenically.
1499:
Note: this not the half-life of K, but rather the half-life that would correspond to the decay constant for decay to Ar. About 89% of the K decays to Ca.
1050:
of the radioactive parent isotope. The values given for half-life and decay constant are the current consensus values in the
Isotope Geology community.
899:
In comparison with the quantity of the radioactive 'parent isotope' in a system, the quantity of the radiogenic 'daughter product' is used as a
1599:
Government supply of radionuclides; information on isotopes; coordination and management of isotope production, availability, and distribution
910:
In comparison with the quantity of a non-radiogenic isotope of the same element, the quantity of the radiogenic isotope is used to define its
855:
769:
1019:
practice, this occurs for all radionuclides with half lives less than about 50 to 100 million years. Such nuclides are formed in
983:(half-life around 5700 years), but the carbon-14 was formed some time earlier from nitrogen-14 by the action of cosmic rays.
118:
1046:
The following table lists some of the most important radiogenic isotope systems used in geology, in order of decreasing
422:
810:
1381:
1369:
614:
319:
848:
632:
602:
103:
679:
229:
17:
972:. Almost all the argon in the Earth's atmosphere is radiogenic, whereas primordial argon is argon-36.
565:
1388:. Most of the radiogenic heating in the Earth results from the decay of the daughter nuclei in the
953:
present primordially, while the other three isotopes may also occur as radiogenic decay products of
1536:
841:
828:
560:
264:
904:
555:
452:
417:
113:
1605:
U.S. Department of Energy program for isotope production and production research and development
1618:
1385:
928:
induced) processes that produce them in nature freshly. A few others are naturally produced by
609:
259:
224:
1510:
734:
619:
511:
674:
1567:
1024:
915:
744:
719:
536:
8:
1544:
1015:
and meteorites, which are relatively free of parental sources for helium-3 and helium-4.
949:(Pb, Pb, Pb, and Pb) are present primordially, in known and fixed ratios. However, Pb is
895:) form some of the most important tools in geology. They are used in two principal ways:
639:
518:
412:
355:
348:
338:
279:
274:
108:
1467:
1418:
911:
900:
582:
577:
1365:
877:
754:
749:
709:
587:
326:
314:
297:
269:
239:
80:
1482:
1448:
1373:
946:
774:
764:
694:
447:
365:
333:
153:
85:
932:
processes (natural nuclear reactions of other types, such as neutron absorption).
1377:
1008:
759:
739:
714:
644:
531:
459:
405:
370:
30:
1602:
1486:
1423:
936:
885:
815:
669:
664:
543:
476:
284:
219:
196:
183:
170:
70:
48:
1612:
794:
789:
784:
779:
729:
387:
360:
204:
143:
96:
75:
1401:
1035:
914:(e.g. Pb/Pb). This technique is discussed in more detail under the heading
881:
724:
699:
684:
429:
377:
234:
1603:
Isotope
Development & Production for Research and Applications (IDPRA)
1452:
1372:(resulting from planetary accretion), radiogenic heating occurring in the
1038:(also inferred from extra magnesium-26 found in meteorites), and iron-60.
1413:
1397:
1393:
1389:
929:
689:
382:
304:
157:
1368:
during the production of radiogenic nuclides. Along with heat from the
1031:
1012:
659:
649:
506:
486:
309:
179:
1047:
1020:
980:
969:
704:
654:
481:
469:
464:
343:
1466:
Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021).
999:
995:
976:
38:
1004:
958:
954:
945:
is perhaps the best example of a partly radiogenic substance, as
873:
166:
139:
131:
63:
53:
991:
58:
935:
For radiogenic isotopes that decay slowly enough, or that are
1568:"Geoneutrinos make their debut; Radiogenic heat in the Earth"
987:
965:
1007:(H) which is a product of some nuclear reactions, including
942:
1596:
1027:, since they are not seen directly on the Earth today.
1364:
occurs as a result of the release of heat energy from
1041:
1508:
1465:
986:
Other important examples of radiogenic elements are
891:Radiogenic nuclides (more commonly referred to as
1468:"The NUBASE2020 evaluation of nuclear properties"
1610:
1056:indicates ultimate decay product of a series.
849:
1442:
979:-14 is radiogenic, coming from the decay of
856:
842:
1459:
1030:An example of an extinct radionuclide is
14:
1611:
1509:Allaby, Alisa; Michael Allaby (1999).
964:Another notable radiogenic nuclide is
1528:
1502:
1356:
1565:
1597:National Isotope Development Center
1559:
1042:Radiogenic nuclides used in geology
24:
1534:
880:. It may itself be radioactive (a
25:
1630:
1590:
876:that is produced by a process of
1541:Introduction to Earth Sciences I
823:
822:
809:
37:
1547:. p. 3.2 Mantle convection
947:all four of its stable isotopes
1515:A Dictionary of Earth Sciences
1493:
1447:. Cambridge University Press.
1436:
13:
1:
1429:
968:-40, formed from radioactive
1566:Dumé, Belle (27 July 2005).
1537:"The Earth as a Heat Engine"
7:
1407:
922:
603:High-energy nuclear physics
10:
1635:
1445:Radiogenic Isotope Geology
1067:kyr = kiloyear = 10 years
905:uranium–lead geochronology
1065:Myr = megayear = 10 years
1063:Gyr = gigayear = 10 years
1487:10.1088/1674-1137/abddae
1382:two main sources of heat
1060:Units used in this table
114:Interacting boson model
1574:. Institute of Physics
1453:10.1017/9781316163009
1443:Dickin, A.P. (2018).
1025:extinct radionuclides
501:High-energy processes
199:– equal all the above
97:Models of the nucleus
1511:"radiogenic heating"
1079:Decay constant (yr)
916:isotope geochemistry
537:nuclear astrophysics
1545:Columbia University
1023:, but are known as
893:radiogenic isotopes
519:Photodisintegration
442:Capturing processes
356:Spontaneous fission
349:Internal conversion
280:Valley of stability
275:Island of stability
109:Nuclear shell model
1419:Radiometric dating
1362:Radiogenic heating
1357:Radiogenic heating
912:isotopic signature
901:radiometric dating
870:radiogenic nuclide
816:Physics portal
610:Quark–gluon plasma
393:Radiogenic nuclide
1475:Chinese Physics C
1366:radioactive decay
1354:
1353:
1076:Daughter nuclide
878:radioactive decay
866:
865:
552:
298:Radioactive decay
254:Nuclear stability
81:Nuclear structure
16:(Redirected from
1626:
1584:
1583:
1581:
1579:
1563:
1557:
1556:
1554:
1552:
1535:Mutter, John C.
1532:
1526:
1525:
1523:
1521:
1506:
1500:
1497:
1491:
1490:
1472:
1463:
1457:
1456:
1440:
1386:Earth's interior
1070:
1069:
858:
851:
844:
831:
826:
825:
818:
814:
813:
690:Skłodowska-Curie
550:
366:Neutron emission
134:' classification
86:Nuclear reaction
41:
27:
26:
21:
1634:
1633:
1629:
1628:
1627:
1625:
1624:
1623:
1609:
1608:
1593:
1588:
1587:
1577:
1575:
1564:
1560:
1550:
1548:
1533:
1529:
1519:
1517:
1507:
1503:
1498:
1494:
1470:
1464:
1460:
1441:
1437:
1432:
1410:
1370:Primordial Heat
1359:
1273:
1073:Parent nuclide
1066:
1064:
1062:
1055:
1044:
1009:ternary fission
937:stable isotopes
925:
884:) or stable (a
862:
821:
808:
807:
800:
799:
635:
625:
624:
605:
595:
594:
539:
535:
532:Nucleosynthesis
524:
523:
502:
494:
493:
443:
435:
434:
408:
406:Nuclear fission
398:
397:
371:Proton emission
300:
290:
289:
255:
247:
246:
148:
135:
124:
123:
99:
31:Nuclear physics
23:
22:
15:
12:
11:
5:
1632:
1622:
1621:
1607:
1606:
1600:
1592:
1591:External links
1589:
1586:
1585:
1558:
1527:
1501:
1492:
1458:
1434:
1433:
1431:
1428:
1427:
1426:
1424:Stable nuclide
1421:
1416:
1409:
1406:
1358:
1355:
1352:
1351:
1348:
1345:
1342:
1338:
1337:
1334:
1331:
1328:
1324:
1323:
1320:
1317:
1314:
1310:
1309:
1306:
1303:
1300:
1296:
1295:
1292:
1289:
1286:
1282:
1281:
1278:
1275:
1270:
1266:
1265:
1262:
1259:
1256:
1252:
1251:
1248:
1245:
1242:
1238:
1237:
1234:
1231:
1228:
1224:
1223:
1220:
1217:
1214:
1210:
1209:
1206:
1203:
1200:
1196:
1195:
1192:
1189:
1186:
1182:
1181:
1178:
1175:
1172:
1168:
1167:
1164:
1161:
1158:
1154:
1153:
1150:
1147:
1144:
1140:
1139:
1136:
1133:
1130:
1126:
1125:
1122:
1119:
1116:
1112:
1111:
1108:
1105:
1102:
1098:
1097:
1094:
1091:
1088:
1084:
1083:
1080:
1077:
1074:
1053:
1043:
1040:
924:
921:
920:
919:
908:
886:stable nuclide
864:
863:
861:
860:
853:
846:
838:
835:
834:
833:
832:
819:
802:
801:
798:
797:
792:
787:
782:
777:
772:
767:
762:
757:
752:
747:
742:
737:
732:
727:
722:
717:
712:
707:
702:
697:
692:
687:
682:
677:
672:
667:
662:
657:
652:
647:
642:
636:
631:
630:
627:
626:
623:
622:
617:
612:
606:
601:
600:
597:
596:
593:
592:
591:
590:
585:
580:
571:
570:
569:
568:
563:
558:
547:
546:
544:Nuclear fusion
540:
530:
529:
526:
525:
522:
521:
516:
515:
514:
503:
500:
499:
496:
495:
492:
491:
490:
489:
484:
474:
473:
472:
467:
457:
456:
455:
444:
441:
440:
437:
436:
433:
432:
427:
426:
425:
415:
409:
404:
403:
400:
399:
396:
395:
390:
385:
380:
374:
373:
368:
363:
358:
353:
352:
351:
346:
336:
331:
330:
329:
324:
323:
322:
307:
301:
296:
295:
292:
291:
288:
287:
285:Stable nuclide
282:
277:
272:
267:
262:
260:Binding energy
256:
253:
252:
249:
248:
245:
244:
243:
242:
232:
227:
222:
216:
215:
201:
200:
193:
192:
176:
175:
163:
162:
150:
149:
136:
130:
129:
126:
125:
122:
121:
116:
111:
106:
100:
95:
94:
91:
90:
89:
88:
83:
78:
73:
71:Nuclear matter
68:
67:
66:
61:
51:
43:
42:
34:
33:
9:
6:
4:
3:
2:
1631:
1620:
1619:Radioactivity
1617:
1616:
1614:
1604:
1601:
1598:
1595:
1594:
1573:
1572:Physics World
1569:
1562:
1546:
1542:
1538:
1531:
1516:
1512:
1505:
1496:
1488:
1484:
1481:(3): 030001.
1480:
1476:
1469:
1462:
1454:
1450:
1446:
1439:
1435:
1425:
1422:
1420:
1417:
1415:
1412:
1411:
1405:
1403:
1399:
1395:
1391:
1387:
1383:
1379:
1375:
1371:
1367:
1363:
1349:
1346:
1343:
1340:
1339:
1335:
1332:
1329:
1326:
1325:
1321:
1318:
1315:
1312:
1311:
1307:
1304:
1301:
1298:
1297:
1293:
1290:
1287:
1284:
1283:
1279:
1276:
1271:
1268:
1267:
1263:
1260:
1257:
1254:
1253:
1249:
1246:
1243:
1240:
1239:
1235:
1232:
1229:
1226:
1225:
1221:
1218:
1215:
1212:
1211:
1207:
1204:
1201:
1198:
1197:
1193:
1190:
1187:
1184:
1183:
1179:
1176:
1173:
1170:
1169:
1165:
1162:
1159:
1156:
1155:
1151:
1148:
1145:
1142:
1141:
1137:
1134:
1131:
1128:
1127:
1123:
1120:
1117:
1114:
1113:
1109:
1106:
1103:
1100:
1099:
1095:
1092:
1089:
1086:
1085:
1081:
1078:
1075:
1072:
1071:
1068:
1061:
1057:
1051:
1049:
1039:
1037:
1033:
1028:
1026:
1022:
1016:
1014:
1010:
1006:
1001:
997:
993:
989:
984:
982:
978:
973:
971:
967:
962:
960:
956:
952:
948:
944:
940:
938:
933:
931:
917:
913:
909:
906:
902:
898:
897:
896:
894:
889:
887:
883:
879:
875:
871:
859:
854:
852:
847:
845:
840:
839:
837:
836:
830:
820:
817:
812:
806:
805:
804:
803:
796:
793:
791:
788:
786:
783:
781:
778:
776:
773:
771:
768:
766:
763:
761:
758:
756:
753:
751:
748:
746:
743:
741:
738:
736:
733:
731:
728:
726:
723:
721:
718:
716:
713:
711:
708:
706:
703:
701:
698:
696:
693:
691:
688:
686:
683:
681:
678:
676:
673:
671:
668:
666:
663:
661:
658:
656:
653:
651:
648:
646:
643:
641:
638:
637:
634:
629:
628:
621:
618:
616:
613:
611:
608:
607:
604:
599:
598:
589:
586:
584:
581:
579:
576:
575:
573:
572:
567:
564:
562:
559:
557:
554:
553:
549:
548:
545:
542:
541:
538:
533:
528:
527:
520:
517:
513:
512:by cosmic ray
510:
509:
508:
505:
504:
498:
497:
488:
485:
483:
480:
479:
478:
475:
471:
468:
466:
463:
462:
461:
458:
454:
451:
450:
449:
446:
445:
439:
438:
431:
428:
424:
423:pair breaking
421:
420:
419:
416:
414:
411:
410:
407:
402:
401:
394:
391:
389:
388:Decay product
386:
384:
381:
379:
376:
375:
372:
369:
367:
364:
362:
361:Cluster decay
359:
357:
354:
350:
347:
345:
342:
341:
340:
337:
335:
332:
328:
325:
321:
318:
317:
316:
313:
312:
311:
308:
306:
303:
302:
299:
294:
293:
286:
283:
281:
278:
276:
273:
271:
268:
266:
263:
261:
258:
257:
251:
250:
241:
238:
237:
236:
233:
231:
228:
226:
223:
221:
218:
217:
214:
210:
206:
205:Mirror nuclei
203:
202:
198:
195:
194:
191:
190:
187: −
186:
181:
178:
177:
174:
173:
168:
165:
164:
161:
160:
155:
152:
151:
147:
146:
141:
138:
137:
133:
128:
127:
120:
117:
115:
112:
110:
107:
105:
102:
101:
98:
93:
92:
87:
84:
82:
79:
77:
76:Nuclear force
74:
72:
69:
65:
62:
60:
57:
56:
55:
52:
50:
47:
46:
45:
44:
40:
36:
35:
32:
29:
28:
19:
1576:. Retrieved
1571:
1561:
1549:. Retrieved
1540:
1530:
1518:. Retrieved
1514:
1504:
1495:
1478:
1474:
1461:
1444:
1438:
1402:potassium-40
1390:decay chains
1380:make up the
1361:
1360:
1191:1.55125 ×10
1059:
1058:
1052:
1045:
1036:aluminium-26
1029:
1017:
985:
974:
963:
950:
941:
934:
926:
892:
890:
882:radionuclide
869:
867:
430:Photofission
392:
378:Decay energy
305:Alpha α
212:
208:
188:
184:
171:
158:
144:
1578:23 November
1551:23 November
1520:24 November
1414:Geoneutrino
1398:thorium-232
1394:uranium-238
1333:1.2097 ×10
1305:9.1577 ×10
1294:245.25 kyr
1222:0.7038 Gyr
1219:9.8485 ×10
1163:4.9475 ×10
930:nucleogenic
903:tool (e.g.
735:Oppenheimer
413:Spontaneous
383:Decay chain
334:K/L capture
310:Beta β
180:Isodiaphers
104:Liquid drop
1430:References
1322:32.76 kyr
1319:2.116 ×10
1308:75.69 kyr
1291:2.826 ×10
1208:1.397 Gyr
1205:4.962 ×10
1194:4.468 Gyr
1180:11.93 Gyr
1166:14.01 Gyr
1149:1.867 ×10
1135:1.666 ×10
1124:49.44 Gyr
1121:1.402 ×10
1093:1.477 ×10
1082:Half-life
1032:iodine-129
1021:supernovas
1013:Moon rocks
765:Strassmann
755:Rutherford
633:Scientists
588:Artificial
583:Cosmogenic
578:Primordial
574:Nuclides:
551:Processes:
507:Spallation
18:Radiogenic
1347:4.33 ×10
1277:2.24 ×10
1264:0.70 Myr
1177:5.81 ×10
1152:37.1 Gyr
1138:41.6 Gyr
1107:6.54 ×10
1048:half-life
981:carbon-14
970:potassium
770:Świątecki
685:Pi. Curie
680:Fr. Curie
675:Ir. Curie
670:Cockcroft
645:Becquerel
566:Supernova
270:Drip line
265:p–n ratio
240:Borromean
119:Ab initio
1613:Category
1408:See also
1350:1600 yr
1336:5730 yr
1280:310 kyr
1272:Ar (98%)
1261:9.9 ×10
1250:1.5 Myr
1247:4.6 ×10
1233:4.3 ×10
1110:106 Gyr
1096:483 Gyr
1000:helium-4
996:helium-3
977:nitrogen
923:Examples
829:Category
730:Oliphant
715:Lawrence
695:Davisson
665:Chadwick
561:Big Bang
448:electron
418:Products
339:Isomeric
230:Even/odd
207: –
182:– equal
169:– equal
167:Isotones
156:– equal
142:– equal
140:Isotopes
132:Nuclides
54:Nucleons
1384:in the
1274:S (2%)
1236:16 Myr
1005:tritium
959:thorium
955:uranium
874:nuclide
785:Thomson
775:Szilárd
745:Purcell
725:Meitner
660:N. Bohr
655:A. Bohr
640:Alvarez
556:Stellar
460:neutron
344:Gamma γ
197:Isomers
154:Isobars
49:Nucleus
1400:, and
1374:mantle
992:helium
827:
795:Wigner
790:Walton
780:Teller
710:Jensen
477:proton
220:Stable
1471:(PDF)
1378:crust
1216:Pb**
1188:Pb**
1160:Pb**
988:radon
975:Some
966:argon
872:is a
760:Soddy
740:Proca
720:Mayer
700:Fermi
650:Bethe
225:Magic
1580:2013
1553:2013
1522:2013
1396:and
1376:and
998:and
990:and
957:and
951:only
943:Lead
750:Rabi
705:Hahn
615:RHIC
235:Halo
1483:doi
1449:doi
1392:of
1344:Rn
1341:Ra
1316:Ac
1313:Pa
1302:Ra
1299:Th
1288:Th
1269:Cl
1258:Mg
1255:Al
1241:Be
1230:Xe
1202:Ca
1174:Ar
1157:Th
1146:Hf
1143:Lu
1132:Os
1129:Re
1118:Sr
1115:Rb
1104:Nd
1101:Sm
1090:Os
1087:Pt
888:).
620:LHC
534:and
1615::
1570:.
1543:.
1539:.
1513:.
1479:45
1477:.
1473:.
1404:.
1330:N
1327:C
1285:U
1244:B
1227:I
1213:U
1199:K
1185:U
1171:K
1054:**
907:).
868:A
487:rp
453:2×
320:0v
315:2β
211:↔
1582:.
1555:.
1524:.
1489:.
1485::
1455:.
1451::
918:.
857:e
850:t
843:v
482:p
470:r
465:s
327:β
213:N
209:Z
189:Z
185:N
172:N
159:A
145:Z
64:n
59:p
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
