Chesapeake Group

Geology

Formations: unnamed (5), Calvert (140), Choptank (54), Eastover (24), Old Church (5), Saint Marys (7), St Mary's (8), St Marys (26), St. Mary's (1), St. Marys (3), Yorktown (28)

Lithologies: not reported (57), "siliciclastic" (6), claystone (94), mudstone (2), siltstone (7), sandstone (122), conglomerate (1), marl (9)

Paleoenvironments: marine indet. (92), terrestrial indet. (4), peritidal (1), shallow subtidal indet. (8), offshore shelf (6), marginal marine indet. (6), coastal indet. (91), estuary/bay (43), lagoonal (1), foreshore (17), shoreface (8), transition zone/lower shoreface (1), offshore (23)

Age range: base of the Late/Upper Oligocene to the top of the Piacenzian or 28.40000 to 2.58800 Ma
Collections

Time interval Ma Country or state Original ID and collection number
Late/Upper Oligocene28.4 - 23.03USA (Virginia) (164631 167201 167203)
Late/Upper Oligocene - Early/Lower Miocene28.4 - 15.97USA (Virginia) (60657)
Aquitanian23.03 - 20.44USA (Virginia) (70517)
Aquitanian23.03 - 20.44USA (Maryland) (70589 71794 71814)
Early/Lower Miocene23.03 - 15.97USA (Virginia) (71653)
Aquitanian - Serravallian23.03 - 11.62USA (Maryland) (231816)
Miocene23.03 - 5.333USA (Maryland) (125939)
Burdigalian20.44 - 15.97USA (Virginia) (57951 57953 57959 85360 89448 89454 89549)
Burdigalian20.44 - 15.97USA (Maryland) (17790 45493 45511 57786 57960 60848 70590 70591 70592 70593 70815 70816 70817 71796 71807 71810 71924 79101 79102)
Burdigalian20.44 - 15.97USA (Delaware) (18579)
Burdigalian - Langhian20.44 - 13.82USA (Maryland) (18518 51718 68977 231819 231820)
Burdigalian - Serravallian20.44 - 11.62USA (Virginia) (105548)
Burdigalian - Serravallian20.44 - 11.62USA (Maryland) (45510 60858 60870 68976 123869 125137 144136)
Barstovian16.3 - 12.5USA (Maryland) (18519)
Langhian15.97 - 13.82USA (Virginia) (28368 48883 57784 57785 57787 66065 70516 71654 71797 71799 71804 71808 71813 79793 207008 231782)
Langhian15.97 - 13.82USA (Maryland) (60379 18516 100214 100213 100212 45498 45502 45506 70826 45509 48884 51724 55517 68975 69023 69024 70818 70819 70820 70823 70824 70827 70834 71615 71634 71647 71795 71805 71809 89550 98328 126602 168458 222691)
Langhian - Serravallian15.97 - 11.62USA (Maryland) (97474 231780)
Serravallian13.82 - 11.62USA (Maryland) (13408 18580 37347 37348 49945 51715 51716 51725 51726 51731 55396 57782 60376 70546 71816 70594 70821 70822 70825 70828 70829 70830 70831 70832 70833 70835 70836 70837 70838 70840 70841 70842 70843 70844 70845 70846 70847 70848 70854 70855 70856 71533 71638 71639 71641 71648 71815 71819 79103 79104 79105 79106 79107 79108 79109 79110 79111 79112 79113 79114 79115 79116 79352 79353 88577 88578 88580 88581 88582 89455 97475 155893 160228 160229 231783)
Serravallian13.82 - 11.62USA (Virginia) (13407 45508 55690 57110 57111 57113 57114 57700 71627 71629 71642 71643 71645 71806 71798 71800 71801 71811 71812 71817 71818 97416 126605 160233 187324 201605)
Tortonian11.62 - 7.246USA (Virginia) (51719 57112 60643 71625 71630 71632 71637 152251)
Tortonian11.62 - 7.246USA (Maryland) (52050 55395 70547 70849 70850 70851 70852 70853 70865 71631 71635 71636 81588 86500 123487 219172 221449 231781)
Late/Upper Miocene11.608 - 5.333USA (Maryland) (51717 51722 51727 51728 51729 51730 51732 51733 68978 69016 69017 69032 73637)
Late/Upper Miocene11.608 - 5.333USA (Virginia) (51720 51723 60629 60676 79751 79752 79754 79756 187943)
Messinian7.246 - 5.333USA (Virginia) (51721 70529 70531 71534 71618 71535 71619 71536 71622 71623 71626 71628 71644 71646 71655 71820 89551 141245 179732)
Early/Lower Pliocene5.333 - 3.6USA (Virginia) (57908)
Zanclean5.333 - 3.6USA (North Carolina) (49982 51591 52582 77580 77581 77582 77583 77584 77585 77586)
Zanclean5.333 - 3.6USA (Virginia) (57906 57907 58986 71620 71624)
Pliocene5.333 - 2.588USA (Arizona) (125975)
Pliocene5.333 - 2.588USA (Virginia) (85158)
Pliocene5.333 - 2.588USA (North Carolina) (49983 61920 61921 61922 61923 62357 123228)
Late/Upper Pliocene3.6 - 2.588USA (Virginia) (60660 60667 71621)
Piacenzian3.6 - 2.588USA (North Carolina) (18550)