144:
361:
171:
819:
1421:
968:
1433:
1053:
94:
1445:
27:
194:
change). These variations provide a lithostratigraphy or lithologic stratigraphy of the rock unit. Key concepts in stratigraphy involve understanding how certain geometric relationships between rock layers arise and what these geometries imply about their original depositional environment. The basic
329:
data for rock units, both directly and inferentially, so that a sequence of time-relative events that created the rocks formation can be derived. The ultimate aim of chronostratigraphy is to place dates on the sequence of deposition of all rocks within a geological region, and then to every region,
333:
A gap or missing strata in the geological record of an area is called a stratigraphic hiatus. This may be the result of a halt in the deposition of sediment. Alternatively, the gap may be due to removal by erosion, in which case it may be called a stratigraphic vacuity. It is called a
447:
This technique is used to date sequences that generally lack fossils or interbedded igneous rocks. The continuous nature of the sampling means that it is also a powerful technique for the estimation of sediment-accumulation rates.
391:
is a chronostratigraphic technique used to date sedimentary and volcanic sequences. The method works by collecting oriented samples at measured intervals throughout a section. The samples are analyzed to determine their detrital
1483:
396:
magnetism (DRM), that is, the polarity of Earth's magnetic field at the time a stratum was deposited. For sedimentary rocks this is possible because, as they fall through the water column, very fine-grained magnetic minerals
409:. Upon burial, that orientation is preserved. For volcanic rocks, magnetic minerals, which form in the melt, orient themselves with the ambient magnetic field, and are fixed in place upon crystallization of the lava.
424:
are the preferred lithologies because the magnetic grains are finer and more likely to orient with the ambient field during deposition. If the ancient magnetic field were oriented similar to today's field
1476:
444:(NRM) to reveal the DRM. Following statistical analysis, the results are used to generate a local magnetostratigraphic column that can then be compared against the Global Magnetic Polarity Time Scale.
299:, which attempts to define a global historical sea-level curve according to inferences from worldwide stratigraphic patterns. Stratigraphy is also commonly used to delineate the nature and extent of
264:
evidence in the rock layers. Strata from widespread locations containing the same fossil fauna and flora are said to be correlatable in time. Biologic stratigraphy was based on
William Smith's
1509:
1469:
288:
was developed during the 19th century, based on the evidence of biologic stratigraphy and faunal succession. This timescale remained a relative scale until the development of
581:(1999) "Cenozoic development of the Norwegian margin 60–64N: sequences and sedimentary response to variable basin physiography and tectonic setting" pp. 293–304
220:
vary with time, and researchers can use those to map subtle changes that occurred in the paleoenvironment. This has led to the specialized field of isotopic stratigraphy.
342:
for a period of time. A physical gap may represent both a period of non-deposition and a period of erosion. A geologic fault may cause the appearance of a hiatus.
1572:
531:
1562:
1567:
1557:
752:
1552:
1547:
793:
484:
685:
668:
643:
618:
598:
1297:
187:
373:
778:
110:
541:
1004:
745:
124:
in the 1790s and early 19th century. Known as the "Father of
English geology", Smith recognized the significance of
182:
Variation in rock units, most obviously displayed as visible layering, is due to physical contrasts in rock type (
1621:
788:
321:
Chronostratigraphy is the branch of stratigraphy that places an absolute age, rather than a relative age on rock
114:
1461:
798:
441:
265:
433:), the strata would retain a normal polarity. If the data indicate that the North Magnetic Pole were near the
738:
1075:
199:, states: in an undeformed stratigraphic sequence, the oldest strata occur at the base of the sequence.
1259:
494:
17:
1042:
803:
406:
121:
186:). This variation can occur vertically as layering (bedding), or laterally, and reflects changes in
468:
292:, which was based on an absolute time framework, leading to the development of chronostratigraphy.
128:
or rock layering and the importance of fossil markers for correlating strata; he created the first
590:
1611:
1500:
1338:
997:
635:
499:
132:
of
England. Other influential applications of stratigraphy in the early 19th century were by
915:
872:
783:
360:
269:
196:
137:
106:
143:
8:
1399:
1363:
1333:
1080:
1032:
509:
426:
388:
365:
351:
285:
1616:
1353:
1292:
1244:
1170:
1131:
1062:
1037:
1027:
930:
557:
377:
316:
289:
82:
1449:
1343:
943:
920:
852:
681:
664:
639:
614:
594:
537:
369:
304:
231:
223:
202:
165:
74:
730:
698:
268:, which predated, and was one of the first and most powerful lines of evidence for,
1437:
1358:
1328:
1254:
1239:
1149:
990:
808:
239:
66:
39:
16:
This article is about the branch of geology. For stratigraphy in archaeology, see
1491:
1378:
1180:
1154:
1101:
905:
895:
676:
251:
78:
238:) and fossil diversity with time, related to seasonal or longer term changes in
1425:
1373:
1307:
1269:
1264:
1216:
1096:
972:
900:
862:
842:
837:
381:
355:
133:
102:
97:
Engraving from
William Smith's monograph on identifying strata based on fossils
58:
380:. New oceanic crust is magnetized as it forms and then it moves away from the
117:
in a 1669 work on the fossilization of organic remains in layers of sediment.
1605:
1404:
1185:
1121:
1070:
887:
847:
504:
479:
463:
326:
217:
70:
393:
1287:
1211:
1144:
1106:
953:
877:
257:
129:
818:
170:
105:
established the theoretical basis for stratigraphy when he introduced the
1526:
1368:
1234:
1190:
1175:
473:
300:
1348:
1323:
1302:
1279:
1206:
1111:
910:
867:
857:
434:
430:
398:
296:
277:
273:
1420:
1052:
967:
533:
Whatever is Under the Earth the
Geological Society of London 1807â2007
205:
studies the changes in the relative proportions of trace elements and
65:) and layering (stratification). It is primarily used in the study of
1394:
1249:
1116:
829:
613:(2nd ed.) London, New York, etc.: Penguin Reference, London, p. 123.
421:
417:
183:
152:
330:
and by extension to provide an entire geologic record of the Earth.
1535:
413:
148:
120:
The first practical large-scale application of stratigraphy was by
35:
226:
documents the often cyclic changes in the relative proportions of
1517:
1226:
1013:
948:
938:
761:
489:
402:
322:
281:
227:
206:
125:
93:
62:
54:
31:
412:
Oriented paleomagnetic core samples are collected in the field;
1493:
458:
440:
Results of the individual samples are analyzed by removing the
261:
214:
210:
191:
175:
718:
713:
708:
26:
1510:
Lists of fossiliferous stratigraphic units by preserved taxon
703:
235:
724:
43:
982:
704:
University of South
Carolina Sequence Stratigraphy Web
140:, who studied the geology of the region around Paris.
760:
585:Fleet, A. J. and Boldy, S. A. R. (editors) (1999)
680:, 1st ed., Amsterdam: Academic Press (Elsevier).
661:Geosystems: An Introduction to Physical Geography
272:. It provides strong evidence for the formation (
1603:
699:ICS Subcommission for Stratigraphic Information
437:, the strata would exhibit reversed polarity.
303:-bearing reservoir rocks, seals, and traps of
1477:
998:
746:
529:
234:), grain size, thickness of sediment layers (
714:University of Georgia (USA) Stratigraphy Lab
663:, 7th ed., New York: Pearson Prentice-Hall.
73:. Stratigraphy has three related subfields:
573:
571:
372:are the result of reversals of the Earth's
46:demonstrate the principles of stratigraphy.
1484:
1470:
1005:
991:
753:
739:
536:. London: Geological Society. p. 78.
88:
794:Principle of cross-cutting relationships
709:International Commission on Stratigraphy
568:
485:International Commission on Stratigraphy
359:
325:. The branch is concerned with deriving
169:
142:
92:
25:
23:Study of rock layers and their formation
1604:
804:Principle of inclusions and components
345:
1465:
986:
734:
727:A global index of stratigraphic terms
587:Petroleum Geology of Northwest Europe
523:
310:
209:within and between lithologic units.
476:(old instrument for studying strata)
195:concept in stratigraphy, called the
159:
1444:
779:Principle of original horizontality
111:principle of original horizontality
13:
817:
653:
245:
14:
1633:
692:
295:One important development is the
1443:
1432:
1431:
1419:
1051:
966:
634:Elsevier Scientific, Amsterdam,
789:Principle of lateral continuity
115:principle of lateral continuity
799:Principle of faunal succession
721:A stratigraphic data provider.
624:
603:
550:
442:natural remanent magnetization
266:principle of faunal succession
178:, showing sedimentary layering
1:
659:Christopherson, R. W., 2008.
516:
81:(biologic stratigraphy), and
589:Geological Society, London,
405:, orienting themselves with
57:concerned with the study of
7:
1076:Geological history of Earth
1012:
677:Stratigraphy and Timescales
630:Chapman, Richard E. (1983)
451:
77:(lithologic stratigraphy),
10:
1638:
1049:
495:Sedimentary basin analysis
349:
314:
249:
188:environments of deposition
163:
18:Stratigraphy (archaeology)
15:
1585:
1543:
1534:
1525:
1516:
1507:
1413:
1387:
1316:
1278:
1225:
1199:
1163:
1130:
1090:Composition and structure
1089:
1061:
1043:Index of geology articles
1020:
962:
929:
886:
828:
815:
769:
260:stratigraphy is based on
888:Geomorphologic processes
771:Stratigraphic principles
764:principles and processes
469:Conodont biostratigraphy
420:, and very fine-grained
609:Kearey, Philip (2001).
338:because deposition was
85:(stratigraphy by age).
1622:Methods in archaeology
954:Mass wasting processes
822:
530:Davies G.L.H. (2007).
407:Earth's magnetic field
385:
179:
156:
98:
89:Historical development
47:
1339:Environmental geology
830:Petrologic principles
821:
674:Montenari, M., 2016.
611:Dictionary of Geology
500:Sequence stratigraphy
435:South Rotational Pole
431:North Rotational Pole
363:
173:
146:
96:
42:area of southeastern
29:
1298:Planetary geophysics
916:Marine transgression
784:Law of superposition
270:biological evolution
197:law of superposition
138:Alexandre Brongniart
107:law of superposition
1497:stratigraphic units
1400:Petroleum geologist
1364:Forensic geophysics
1334:Engineering geology
1081:Timeline of geology
1033:Glossary of geology
510:Tectonostratigraphy
427:North Magnetic Pole
401:) behave like tiny
397:(< 17
389:Magnetostratigraphy
384:in both directions.
366:magnetostratigraphy
352:Magnetostratigraphy
346:Magnetostratigraphy
286:geologic time scale
256:Biostratigraphy or
1426:Geology portal
1354:Geologic modelling
1293:Geophysical survey
1245:Geodetic astronomy
1171:Structural geology
1132:Historical geology
1063:History of geology
1038:History of geology
1028:Outline of geology
973:Geology portal
931:Sediment transport
823:
386:
378:seafloor spreading
317:Chronostratigraphy
311:Chronostratigraphy
290:radiometric dating
180:
157:
99:
83:chronostratigraphy
48:
1599:
1598:
1595:
1594:
1591:
1590:
1587:
1581:
1580:
1459:
1458:
1344:Planetary geology
1260:Planetary geodesy
980:
979:
949:Glacial processes
944:Aeolian processes
939:Fluvial processes
921:Marine regression
686:978-0-12-811549-7
669:978-0-13-600598-8
644:978-0-444-42165-4
632:Petroleum Geology
619:978-0-14-051494-0
599:978-1-86239-039-3
577:Martinsen, O. J.
305:petroleum geology
224:Cyclostratigraphy
203:Chemostratigraphy
166:Lithostratigraphy
160:Lithostratigraphy
75:lithostratigraphy
1629:
1586:
1573:Thalattosuchians
1541:
1540:
1532:
1531:
1523:
1522:
1486:
1479:
1472:
1463:
1462:
1447:
1446:
1435:
1434:
1424:
1423:
1359:Forensic geology
1329:Economic geology
1255:Gravity of Earth
1150:Paleoclimatology
1055:
1007:
1000:
993:
984:
983:
971:
970:
755:
748:
741:
732:
731:
719:Stratigraphy.net
647:
628:
622:
607:
601:
575:
566:
565:
554:
548:
547:
527:
370:Magnetic stripes
327:geochronological
174:Chalk layers in
101:Catholic priest
40:Colorado Plateau
1637:
1636:
1632:
1631:
1630:
1628:
1627:
1626:
1602:
1601:
1600:
1577:
1512:
1503:
1490:
1460:
1455:
1418:
1409:
1383:
1379:Mineral physics
1312:
1274:
1221:
1195:
1181:Plate tectonics
1159:
1155:Palaeogeography
1126:
1102:Crystallography
1085:
1057:
1056:
1047:
1016:
1011:
981:
976:
965:
958:
925:
906:Tectonic uplift
896:Plate tectonics
882:
824:
813:
765:
759:
695:
656:
654:Further reading
651:
650:
629:
625:
608:
604:
576:
569:
556:
555:
551:
544:
528:
524:
519:
514:
454:
358:
350:Main articles:
348:
319:
313:
254:
252:Biostratigraphy
248:
246:Biostratigraphy
168:
162:
91:
79:biostratigraphy
53:is a branch of
24:
21:
12:
11:
5:
1635:
1625:
1624:
1619:
1614:
1597:
1596:
1593:
1592:
1589:
1588:
1583:
1582:
1579:
1578:
1576:
1575:
1570:
1565:
1560:
1555:
1550:
1544:
1538:
1529:
1520:
1514:
1513:
1508:
1505:
1504:
1489:
1488:
1481:
1474:
1466:
1457:
1456:
1454:
1453:
1441:
1429:
1414:
1411:
1410:
1408:
1407:
1402:
1397:
1391:
1389:
1385:
1384:
1382:
1381:
1376:
1374:Mining geology
1371:
1366:
1361:
1356:
1351:
1346:
1341:
1336:
1331:
1326:
1320:
1318:
1314:
1313:
1311:
1310:
1308:Tectonophysics
1305:
1300:
1295:
1290:
1284:
1282:
1276:
1275:
1273:
1272:
1270:Geopositioning
1267:
1265:Remote sensing
1262:
1257:
1252:
1247:
1242:
1237:
1231:
1229:
1223:
1222:
1220:
1219:
1217:Marine geology
1214:
1209:
1203:
1201:
1197:
1196:
1194:
1193:
1188:
1183:
1178:
1173:
1167:
1165:
1161:
1160:
1158:
1157:
1152:
1147:
1142:
1136:
1134:
1128:
1127:
1125:
1124:
1119:
1114:
1109:
1104:
1099:
1097:Cosmochemistry
1093:
1091:
1087:
1086:
1084:
1083:
1078:
1073:
1067:
1065:
1059:
1058:
1050:
1048:
1046:
1045:
1040:
1035:
1030:
1024:
1022:
1018:
1017:
1010:
1009:
1002:
995:
987:
978:
977:
963:
960:
959:
957:
956:
951:
946:
941:
935:
933:
927:
926:
924:
923:
918:
913:
908:
903:
901:Salt tectonics
898:
892:
890:
884:
883:
881:
880:
875:
870:
865:
863:Soil formation
860:
855:
850:
845:
840:
834:
832:
826:
825:
816:
814:
812:
811:
806:
801:
796:
791:
786:
781:
775:
773:
767:
766:
758:
757:
750:
743:
735:
729:
728:
722:
716:
711:
706:
701:
694:
693:External links
691:
690:
689:
672:
655:
652:
649:
648:
623:
602:
567:
562:sepmstrata.org
549:
543:978-1862392144
542:
521:
520:
518:
515:
513:
512:
507:
502:
497:
492:
487:
482:
477:
471:
466:
461:
455:
453:
450:
382:midocean ridge
374:magnetic poles
356:Paleomagnetism
347:
344:
315:Main article:
312:
309:
250:Main article:
247:
244:
240:palaeoclimates
230:(particularly
218:isotope ratios
164:Main article:
161:
158:
134:Georges Cuvier
103:Nicholas Steno
90:
87:
71:volcanic rocks
38:strata of the
22:
9:
6:
4:
3:
2:
1634:
1623:
1620:
1618:
1615:
1613:
1610:
1609:
1607:
1584:
1574:
1571:
1569:
1566:
1564:
1561:
1559:
1556:
1554:
1551:
1549:
1546:
1545:
1542:
1539:
1537:
1533:
1530:
1528:
1524:
1521:
1519:
1515:
1511:
1506:
1502:
1499:by preserved
1498:
1495:
1494:fossiliferous
1487:
1482:
1480:
1475:
1473:
1468:
1467:
1464:
1452:
1451:
1442:
1440:
1439:
1430:
1428:
1427:
1422:
1416:
1415:
1412:
1406:
1405:Volcanologist
1403:
1401:
1398:
1396:
1393:
1392:
1390:
1386:
1380:
1377:
1375:
1372:
1370:
1367:
1365:
1362:
1360:
1357:
1355:
1352:
1350:
1347:
1345:
1342:
1340:
1337:
1335:
1332:
1330:
1327:
1325:
1322:
1321:
1319:
1315:
1309:
1306:
1304:
1301:
1299:
1296:
1294:
1291:
1289:
1286:
1285:
1283:
1281:
1277:
1271:
1268:
1266:
1263:
1261:
1258:
1256:
1253:
1251:
1248:
1246:
1243:
1241:
1240:Earth's orbit
1238:
1236:
1233:
1232:
1230:
1228:
1224:
1218:
1215:
1213:
1210:
1208:
1205:
1204:
1202:
1198:
1192:
1189:
1187:
1186:Geomorphology
1184:
1182:
1179:
1177:
1174:
1172:
1169:
1168:
1166:
1164:Dynamic Earth
1162:
1156:
1153:
1151:
1148:
1146:
1143:
1141:
1138:
1137:
1135:
1133:
1129:
1123:
1122:Sedimentology
1120:
1118:
1115:
1113:
1110:
1108:
1105:
1103:
1100:
1098:
1095:
1094:
1092:
1088:
1082:
1079:
1077:
1074:
1072:
1071:Geochronology
1069:
1068:
1066:
1064:
1060:
1054:
1044:
1041:
1039:
1036:
1034:
1031:
1029:
1026:
1025:
1023:
1019:
1015:
1008:
1003:
1001:
996:
994:
989:
988:
985:
975:
974:
969:
961:
955:
952:
950:
947:
945:
942:
940:
937:
936:
934:
932:
928:
922:
919:
917:
914:
912:
909:
907:
904:
902:
899:
897:
894:
893:
891:
889:
885:
879:
876:
874:
871:
869:
866:
864:
861:
859:
856:
854:
851:
849:
846:
844:
841:
839:
836:
835:
833:
831:
827:
820:
810:
809:Walther's law
807:
805:
802:
800:
797:
795:
792:
790:
787:
785:
782:
780:
777:
776:
774:
772:
768:
763:
756:
751:
749:
744:
742:
737:
736:
733:
726:
723:
720:
717:
715:
712:
710:
707:
705:
702:
700:
697:
696:
687:
683:
679:
678:
673:
670:
666:
662:
658:
657:
645:
641:
637:
633:
627:
620:
616:
612:
606:
600:
596:
592:
588:
584:
580:
574:
572:
563:
559:
558:"SEPM Strata"
553:
545:
539:
535:
534:
526:
522:
511:
508:
506:
505:Sadler effect
503:
501:
498:
496:
493:
491:
488:
486:
483:
481:
480:Harris matrix
478:
475:
472:
470:
467:
465:
464:Bed (geology)
462:
460:
457:
456:
449:
445:
443:
438:
436:
432:
428:
423:
419:
415:
410:
408:
404:
400:
395:
390:
383:
379:
375:
371:
367:
362:
357:
353:
343:
341:
337:
331:
328:
324:
318:
308:
306:
302:
298:
293:
291:
287:
283:
279:
275:
271:
267:
263:
259:
258:paleontologic
253:
243:
241:
237:
233:
229:
225:
221:
219:
216:
212:
208:
204:
200:
198:
193:
189:
185:
177:
172:
167:
154:
150:
145:
141:
139:
135:
131:
127:
123:
122:William Smith
118:
116:
112:
108:
104:
95:
86:
84:
80:
76:
72:
68:
64:
60:
56:
52:
45:
41:
37:
33:
28:
19:
1612:Stratigraphy
1496:
1448:
1436:
1417:
1317:Applications
1288:Geomagnetism
1212:Hydrogeology
1145:Paleontology
1140:Stratigraphy
1139:
1107:Geochemistry
964:
878:Metamorphism
770:
725:Agenames.org
675:
660:
631:
626:
610:
605:
586:
582:
578:
561:
552:
532:
525:
446:
439:
411:
387:
339:
335:
332:
320:
294:
255:
222:
201:
181:
130:geologic map
119:
100:
69:and layered
51:Stratigraphy
50:
49:
1563:Plesiosaurs
1527:Vertebrates
1388:Occupations
1369:Meteoritics
1235:Cartography
1191:Volcanology
1176:Geodynamics
853:Exfoliation
474:Erygmascope
364:Example of
301:hydrocarbon
67:sedimentary
1606:Categories
1568:Pterosaurs
1558:Phytosaurs
1349:Geobiology
1324:Biogeology
1303:Seismology
1280:Geophysics
1207:Glaciology
1112:Mineralogy
911:Subsidence
873:Compaction
868:Diagenesis
858:Weathering
517:References
422:sandstones
418:siltstones
297:Vail curve
278:extinction
274:speciation
232:carbonates
190:(known as
147:Strata in
1617:Petrology
1553:Mosasaurs
1548:Dinosaurs
1492:Lists of
1395:Geologist
1250:Geomatics
1117:Petrology
1021:Overviews
843:Extrusive
838:Intrusive
429:near the
414:mudstones
403:compasses
184:lithology
153:Argentina
1536:Reptiles
848:Volcanic
762:Geologic
591:page 295
452:See also
394:remanent
228:minerals
207:isotopes
149:Cafayate
113:and the
61:layers (
36:Jurassic
34:through
1518:Animals
1450:Geology
1438:Geology
1227:Geodesy
1014:Geology
490:Key bed
340:on hold
282:species
55:geology
32:Permian
684:
667:
642:
617:
597:
579:et al.
540:
459:Assise
336:hiatus
323:strata
284:. The
276:) and
262:fossil
236:varves
215:oxygen
211:Carbon
192:facies
176:Cyprus
126:strata
109:, the
63:strata
1501:taxon
1200:Water
636:p. 33
682:ISBN
665:ISBN
640:ISBN
615:ISBN
595:ISBN
538:ISBN
376:and
354:and
213:and
136:and
59:rock
44:Utah
30:The
280:of
1608::
638:,
593:,
583:In
570:^
560:.
416:,
399:Ξm
368:.
307:.
242:.
1485:e
1478:t
1471:v
1006:e
999:t
992:v
754:e
747:t
740:v
688:.
671:.
646:.
621:.
564:.
546:.
425:(
155:)
151:(
20:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
.jpg)
