1. GLACIAL AND POST GLACIAL HISTORY ICE LAKES ISOSTATIC REBOUND TYPICAL STRATIGRAPHY POLLEN AND CLIMATE

2. WORLD ICE COVER

3. WATCH ICE RETREAT as well as SEA and LAND LEVEL RISE

4. GLOBAL SEA LEVEL HISTORY

5. Ridge et al., 1999 Dyke & Prest, 1987 Radiocarbon Ages Ice Extent +Thickness = Ice Volume =  Sea Level

6. History Geology of Vermont, Edward Hitchcock, 1861 Mt. Mansfield Erratic Ludlow, VT Striae

7. Unweathered erratics and weak soils suggest overrunning by LGM ice. Mt. Washington Erratics Mt. Katahdin Soil

8. “Common COSMOGENIC Nuclides”......

9. Target Atoms 10 Be: O, Mg, Si, Fe 26 Al: Si, Al, Fe n 3n3n 4p Spallation How are csi’s made? Muons? < 3% t 1/2 = 700 ky t 1/2 = 1500 ky 5 to 40 at g -1 yr -1

10. For long-lived or stable nuclides N = P*t + Inheritance

11. Goofer Point (block, bedrock, boulder) Summit (block) Tuckerman (block) Mt. Washington Long-standing Dogma All of New England overrun and rock surfaces eroded by continental ice

12. Basin Ponds Moraine (6 boulders) North Basin (3 boulders) Knife Edge and South Peak (2 bedrock) Baxter Peak (bedrock & block) Cathedral Ridge Mt. Katahdin

13. Summit Block, Baxter Peak 25.6±0.5 ky 1 st indication something is not as expected

14. Polished Bedrock, Knife Edge 11.2 ± 0.4 ky

15. North Basin Boulders (n=3),  = 12.3 ± 0.9 ky 10.9 ± 0.4 ky 11.6 ± 0.4 ky 13.9 ± 0.4 ky On lip

16. Pineo Ridge Calibrated 14 C Age 13.2 to 14.0 ky Average 10 Be: 26 Al Age 13.5 ± 0.6 ky

17. 21.6, 13.4, 13.6 ky 120±3 ky 9.8±0.3 ky Mt. Washington 2 nd indication something is not as expected

18. Mt. Washington and Mt. Katahdin, nunataks during late Wisconsinan? Not likely! 1. fresh erratics 2. weak soils Recession.. younging

19. Was continental ice so thin/cold that it eroded little, leaving nuclides from prior exposure on the summits? cone Sub-summit erosion

20. >500 ky total history BEDROCK 9.3±0.5 ky ERRATIC BAFFIN ISLAND UPLAND

21. Late Glacial Limit Waterloo Cactus Rock Bush, Baraboo, Observatory

22. Cold non-erosive upland ice, warm erosive valley ice Pangnirtung Fjord, Baffin Island New England is not unique; there is an Arctic analog.

23. PREDICTABLE SEQUENCE MEAN WHILE, BACK IN VERMONT

25. EARLYLATER = STOWE GULLY

26. OBSERVATION: LAKE SHORE FEATURES ARE TILTED NORTHSOUTH Rising to the north

27. LAKE SHORELINES CAN BE FOUND AT PREDICTABLE ELEVATIONS

28. WHAT IS IT? ALNUS or ALDER

29. WATCH PINE MOVE NORTH

30. VIEW TOGETHER

31. Delcourt and Delcourt, 1984 Jackson and Whitehead, 1991 Spear et al., 1994 COOL, WET? meridional flow WARM AND DRY strong westerlies COLD WARMING, MOIST meridional flow Adirondack Mtns. Eastern N. America Pollen, Macrofossils Pollen, Foraminifera COOL, WET? spruce increase COOLING? WARM AND STORMY pine and birch expand WARM AND DRY WARMING White Mtns. Pollen, Macrofossils WARM, DRY? pine and birch expand WARMING COOLING? COOL, WET? spruce increase COLD Max. Seasonality Spruce Minimum 2 4 6 8 10 12 0 14 C year BP