Chicago in what is now Lake Michigan, Glacial Lake Saginaw in front of the Saginaw lobe, and Glacial Lake Whittlesey in what are now the Lakes Huron and Erie basins. As
the Laurentide ice retreated during the Two Creeks Low
Phase, Early Lake Algonquin formed in what are now the
Lakes Michigan and Huron basins, along with Early Lake
Erie and Glacial Lake Iroquois in what is now the Lake
Ontario basin.
By 11.2 kyr BP ice retreat enabled the huge Main Lake
Algonquin to form in what are now the Lakes Michigan and
Huron basins, Glacial Lake Iroquois to be directly connected
to the Champlain Sea, and several small lakes to form in
what is now the southern Lake Superior basin. Further
retreat of ice in the Great Lakes by 10.2 kyr BP resulted in a
reduction in meltwater and the size of all of the Great Lakes
except what is now Lake Superior as the drainage passed
from the North Bay outlet directly in the Atlantic Ocean. The
new lakes are known as Duluth (now Superior), Chippewa
(Michigan), Stanley (Huron), Early Lake Erie, and Early
Lake Ontario. By 8.5 kyr BP the Laurentide ice has completely left the Great Lakes basin, resulting the formation of
Post Minong (Superior), Chippewa (Michigan), Stanley
(Huron), Early Lake Erie, and Early Lake Ontario. The
period between 7.5 and 5.3 kyr BP resulted in the Great
Lakes much as they are today but with slightly higher levels
and is known as the Nipissing stage. This was followed by
the Algoma phase around 2.9 kyr BP.
A huge (170,000
2 miles; 440,000 km
2
) and important
lake formed periodically during the period 12.8–9.0 kyr BP,
called Glacial Lake Agassiz (Teller and Clayton 1983; Teller
Fig. 2.12 Glacial lobes and sublobes of the southern Laurentide Ice
Sheet in north central USA during the late Wisconsinan Glaciation:
G = Grantsburg; W = Wadena; SL = St. Louis; R = Rainey; C =
Chippewa; WV = Wisconsin Valley; L = Langlade; D = Delevan;
H-P = Harvard-Princeton; PE = Peoria; DE = Decatur; EW = East
White; M = Miami; S = Scioto; LC = Lake Champlain; HR = Hudson
River; CV = Connecticut Valley; BB = Buzzards Bay; CC = Cape
Cod; GB = Georges Bank. Dotted line along axis of Lake Michigan
lobe shows location of time-distance diagram shown in original
reference. Light dashed line shows the maximum limit of the ice sheet
(Source Mickelson and Colgan 2003)
28
2 Soil-Forming Factors of the Great Lakes Coastal Zone
the Laurentide ice retreated during the Two Creeks Low
Phase, Early Lake Algonquin formed in what are now the
Lakes Michigan and Huron basins, along with Early Lake
Erie and Glacial Lake Iroquois in what is now the Lake
Ontario basin.
By 11.2 kyr BP ice retreat enabled the huge Main Lake
Algonquin to form in what are now the Lakes Michigan and
Huron basins, Glacial Lake Iroquois to be directly connected
to the Champlain Sea, and several small lakes to form in
what is now the southern Lake Superior basin. Further
retreat of ice in the Great Lakes by 10.2 kyr BP resulted in a
reduction in meltwater and the size of all of the Great Lakes
except what is now Lake Superior as the drainage passed
from the North Bay outlet directly in the Atlantic Ocean. The
new lakes are known as Duluth (now Superior), Chippewa
(Michigan), Stanley (Huron), Early Lake Erie, and Early
Lake Ontario. By 8.5 kyr BP the Laurentide ice has completely left the Great Lakes basin, resulting the formation of
Post Minong (Superior), Chippewa (Michigan), Stanley
(Huron), Early Lake Erie, and Early Lake Ontario. The
period between 7.5 and 5.3 kyr BP resulted in the Great
Lakes much as they are today but with slightly higher levels
and is known as the Nipissing stage. This was followed by
the Algoma phase around 2.9 kyr BP.
A huge (170,000
2 miles; 440,000 km
2
) and important
lake formed periodically during the period 12.8–9.0 kyr BP,
called Glacial Lake Agassiz (Teller and Clayton 1983; Teller
Fig. 2.12 Glacial lobes and sublobes of the southern Laurentide Ice
Sheet in north central USA during the late Wisconsinan Glaciation:
G = Grantsburg; W = Wadena; SL = St. Louis; R = Rainey; C =
Chippewa; WV = Wisconsin Valley; L = Langlade; D = Delevan;
H-P = Harvard-Princeton; PE = Peoria; DE = Decatur; EW = East
White; M = Miami; S = Scioto; LC = Lake Champlain; HR = Hudson
River; CV = Connecticut Valley; BB = Buzzards Bay; CC = Cape
Cod; GB = Georges Bank. Dotted line along axis of Lake Michigan
lobe shows location of time-distance diagram shown in original
reference. Light dashed line shows the maximum limit of the ice sheet
(Source Mickelson and Colgan 2003)
28
2 Soil-Forming Factors of the Great Lakes Coastal Zone