Geology Notes

Glacier: a Flowing Stream of Ice

Mountain
Continental (Greenland, Antarctica)
Snowfall vs Melting & Evaporation (Ablation)

Zone of Accumulation

Snowfall Exceeds Melting & Evaporation
Excess Snow Turns to Ice & Flows Out
Zone of Melting or Ablation

Melting & Evaporation Exceeds Snowfall
Melting Excess Made up by Ice Flowing in
Terminus of Glacier

Snowfall & Inflow = Melting & Evaporation (Ablation)

Results of Glaciation

Abrasion

Polish
Striations
Chatter Marks
Crescentic Gouges
Bedrock Scour
Deposition

Till
Outwash
Varved Clays
Meltwater Erosion

Glacial Landforms

Mountain Glacier Landforms

Evolution of a typical mountain glacier landscape.

Continental Glacier Landforms

Two stages in the retreat of a typical continental glacier.

The Greenland Ice Cap shows the dome-like form of a typical continental glacier.
Glacial Chronology

The table below gives an idea how complex the Pleistocene really was. Ice advances and retreats in different areas are given different names because it is not always certain that they began at the same time everywhere.

Time (1000 Years) Conditions North America Alps Northern Europe Poland-Russia
0-18 Interglacial
18-67 Glacial Wisconsin Wurm Vistula Varsovian
67-128 Interglacial Sangamon Uznach Eem Masovian
128-180 Glacial Illinoisan Riss Warthe/Saale Cracovian
180-230 Interglacial Yarmouth Hoetting Holstein Sandomirian
230-300 Glacial Kansan Mindel Elster Jaroslavian
300-330 Interglacial Aftonian Cromer Likhvin
330-470 Glacial "Nebraskan" Gunz Menapian
470-540 Interglacial Waalian
540-550 Glacial Donau II Weybourne
550-585 Interglacial Tiglian
585-600 Glacial Donau I
600-2000 About 20 Glacial Advances
2000 (2 M.Y.) Beginning of Pleistocene
4000 (4 M.Y.) Dwarf forests still in Antarctica
15 M.Y. First Glaciation in Antarctica
Ice Ages

Pleistocene 3 M.y.
Permian 250-220 M.y.
Ordovician 450 M.y.
Precambrian
900-650 M.y.