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547:. The melting is thought to have occurred because the impacts of the Early Imbrian thinned the overlying rock – either causing the mantle to rise because of the reduced pressure on it, bringing molten material closer to the surface, or the top melting as heat flowed upwards through the mantle because of reduced overlying
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exists from the time spanned by the Early and Late
Imbrian epoch of the Moon, the Early and Late Imbrian has been used by at least one notable scientific work as an unofficial subdivision of the terrestrial
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basin occurred at the start of the epoch. The other large basins that dominate the lunar near side (such as
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epoch occurred from 3,850 million years ago to about 3,800 million years ago. It overlaps the end of the
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Lunar olivine basalt formed around 3.3 billion years ago. This is part of sample 15555, known as
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epoch occurred between 3,800 million years ago to about 3,200 million years ago. It was the
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mostly during the subsequent Late
Imbrian epoch. The Early Imbrian was preceded by the
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551:. The majority of lunar samples returned to earth for study come from this epoch.
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Periods on the Lunar
Geologic Timescale. Axis scale: Millions of years ago.
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W. Harland; R. Armstrong; A. Cox; L. Craig; A. Smith; D. Smith (1990).
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below the lunar basins partially melted and filled them with
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The Hadean does not have any subdivisions recognized by the
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is a lunar geologic period divided into two epochs, the
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49:. Unsourced material may be challenged and removed.
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555:Relationship to Earth's geologic time scale
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109:Learn how and when to remove this message
693:International Commission on Stratigraphy
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47:adding citations to reliable sources
1329:= kiloannum (thousands years ago);
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1333:= megaannum (millions years ago);
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1337:= gigaannum (billions years ago).
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34:needs additional citations for
1:
776:Pleistocene (11.7 ka–2.58 Ma)
1454:. You can help Knowledge by
1446:This article related to the
1397:. You can help Knowledge by
739:Geological history of Earth
1532:
1433:
1376:
1012:Mississippian (323–359 Ma)
1007:Pennsylvanian (299–323 Ma)
771:Holocene (present–11.7 ka)
613:Cambridge University Press
609:A Geologic time scale 1989
1324:
1296:Paleoarchean (3.2–3.6 Ga)
1146:Terreneuvian (521–539 Ma)
688:
660:
588:Hadean eon-related topics
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172:
128:
1291:Mesoarchean (2.8–3.2 Ga)
1136:Miaolingian (497–509 Ma)
981:Guadalupian (260–272 Ma)
833:Paleocene (56.0–66.0 Ma)
823:Oligocene (23.0–33.9 Ma)
697:lunar geologic timescale
529:Lunar geologic timescale
459:lunar geologic timescale
416:Lunar Geologic Timescale
250:−1000 —
240:−1500 —
230:−2000 —
220:−2500 —
210:−3000 —
200:−3500 —
190:−4000 —
180:−4500 —
1286:Neoarchean (2.5–2.8 Ga)
1251:Orosirian (1.8–2.05 Ga)
1246:Statherian (1.6–1.8 Ga)
1189:Cryogenian (635–720 Ma)
1079:Llandovery (433–444 Ma)
986:Cisuralian (272–299 Ma)
797:Pliocene (2.59–5.33 Ma)
260:−500 —
1256:Rhyacian (2.05–2.3 Ga)
1225:Calymmian (1.4–1.6 Ga)
1184:Ediacaran (539–635 Ma)
1131:Furongian (485–497 Ma)
976:Lopingian (252–260 Ma)
802:Miocene (5.33–23.0 Ma)
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477:that created the huge
467:Late Heavy Bombardment
1261:Siderian (2.3–2.5 Ga)
1220:Ectasian (1.2–1.4 Ga)
1141:Series 2 (509–521 Ma)
828:Eocene (33.9–56.0 Ma)
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16:Lunar geologic period
1301:Eoarchean (3.6–4 Ga)
1194:Tonian (720 Ma–1 Ga)
1074:Wenlock (427–433 Ma)
1064:Pridoli (419–423 Ma)
487:Mare Tranquillitatis
43:improve this article
1511:Geochronology stubs
1356: •
1345: •
1343:Geologic time scale
1105:Middle (458–470 Ma)
1069:Ludlow (423–427 Ma)
1038:Middle (383–393 Ma)
933:Middle (237–247 Ma)
902:Middle (164–174 Ma)
559:Since little or no
1354:Geology portal
1215:Stenian (1–1.2 Ga)
1110:Early (470–485 Ma)
1043:Early (393–419 Ma)
938:Early (247–252 Ma)
907:Early (174–201 Ma)
876:Early (100–145 Ma)
871:Late (66.0–100 Ma)
680:Lower Imbrian
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471:Inner Solar System
426:Chronological unit
413:Time scale(s) used
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670:Basin Groups
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1391:geochronology
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1175:(539 Ma–1 Ga)
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952:Paleozoic Era
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862:(66.0–145 Ma)
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463:Early Imbrian
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60: –
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55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
1456:expanding it
1445:
1399:expanding it
1388:
1373:
1339:
1275:Archean Eon
1237:(1.6–2.5 Ga)
1122:(485–539 Ma)
1091:(444–485 Ma)
1055:(419–444 Ma)
1024:(359–419 Ma)
998:(299–359 Ma)
967:(252–299 Ma)
955:(252–539 Ma)
919:(201–252 Ma)
888:(145–201 Ma)
847:Mesozoic Era
747:Cenozoic Era
608:
602:
577:
563:evidence on
558:
533:Late Imbrian
532:
526:
518:
509:Late Imbrian
483:Mare Crisium
479:Mare Imbrium
462:
456:
446:
442:
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407:Earth's Moon
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143:
105:
96:
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79:
72:
65:
53:
41:Please help
36:verification
33:
1311:Hadean Eon
1089:Ordovician
860:Cretaceous
760:Quaternary
520:Great Scott
1516:Moon stubs
1495:Categories
1313:(4–4.6 Ga)
1277:(2.5–4 Ga)
1206:(1–1.6 Ga)
812:Paleogene
654:Hadean Eon
594:References
561:geological
421:Definition
328:Copernican
168:Chronology
99:March 2024
69:newspapers
1340:See also:
1120:Cambrian
1053:Silurian
1022:Devonian
917:Triassic
886:Jurassic
675:Nectarian
503:Nectarian
292:Nectarian
58:"Imbrian"
965:Permian
786:Neogene
582:See also
1501:Imbrian
665:Cryptic
527:In the
469:of the
457:In the
439:Imbrian
305:Imbrian
265:–
255:–
245:–
235:–
225:–
215:–
205:–
195:–
185:–
124:Imbrian
83:scholar
1506:Hadean
1319:
570:Hadean
545:basalt
541:mantle
531:, the
499:basalt
493:, and
475:impact
473:. The
461:, the
430:Period
377:
370:
363:
85:
78:
71:
64:
56:
1450:is a
1389:This
565:Earth
537:epoch
443:Early
353:Early
90:JSTOR
76:books
1452:stub
1448:Moon
1395:stub
447:Late
445:and
437:The
340:Late
139:PreN
62:news
573:eon
45:by
1497::
1335:Ga
1331:Ma
1327:ka
611:.
575:.
505:.
489:,
485:,
449:.
133:Ma
1483:e
1476:t
1469:v
1458:.
1426:e
1419:t
1412:v
1401:.
731:e
724:t
717:v
699:.
646:e
639:t
632:v
615:.
523:.
159:C
154:E
149:N
144:I
112:)
106:(
101:)
97:(
87:·
80:·
73:·
66:·
39:.
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