Title: dog jumping in snow image removed to save space
1- dog jumping in snow image removed to save space
2today
- Logistics
- Silverton Winter Interim course
- Your paper is due 11/20
- Exam two is a week from Thursday
- Cool caves
- Sotano de las Golondrinas, Mexico
- Riverbluff Cave, Missouri
- Karst topography and groundwater
3Sotano de Las Golondrinas
http//youtube.com/watch?vdHKMeMyqKxI
http//youtube.com/watch?vh2bqxZs0iCc
4Riverbluff Cave, MO
- turtle shells
- peccary tracks
- lion and bear scratches on walls
- horse bones
- Douglas fir needles
5Riverbluff Cave, MO
- Never-before-seen turtle shells
- Never-before-seen horse bones
- Ice Age pigs
- 15 foot tall extinct bear scratchings
- American Lion scratchings
- untouched for at least 55 thousand years
- some remains 850,000 yrs. old
6Riverbluff Cave, MO
- stalactites, stalagmites, columns, cave bacon,
draperies, flowstone, soda straws
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9(extinct) American lion scratches
660,000 year old turtle shells
(extinct) short faced bear scratches
http//www.npr.org/templates/story/story.php?story
Id7283494
10Limestone Karst Regions
11Karst topography dissolution of limestone
- Dissolution is particularly important for
sedimentary rocks containing carbonate minerals.
Common carbonate minerals include - calcite (CaCO3) or calcium carbonate in
limestone - dolomite (CaMg(CO3)2 or calcium magnesium
carbonate in dolomite - Ground water is a bit acidic. It contains
carbonic acid (H2CO3), from dissolved carbon
dioxide gas.
12Karst topography dissolution of limestone
So. when you add water (H2O), calcium carbonate
(CaCO3), and carbon dioxide (CO2), you get
calcium bicarbonate (Ca(HCO3)2), which is very
soluble and easily removed! H2O CO2 CaCO3
Ca(HCO3)2
- Calcium carbonate can also be PRECIPITATED, which
means turned from a liquid into a solid - When conditions are right for precipitation,
calcite forms mineral coatings that cement the
existing rock grains together or it can fill
fractures
13cave pearls!
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15- limestone bluff image removed to save space
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17a sink
18caverns
- Large, open underground areas occurring in
massive limestone depositions at or near the
surface - Two Stages of Formation
19caverns two stages of formation
- Initial Excavation
- --Water dissolves the limy bedrock leaves
voids - Decoration Stage
- --Water leaves behind the compounds it had
been carrying - in solution
20speleothems formed by precipitated deposits of
minerals on the wall, floor, or roof of a cave
- Stalactite pendant structure hanging downward
from a caverns roof - Stalagmite projecting structure growing upward
from a caverns floor
?Stalactite
?Stalagmite
Carlsbad Caverns, NM
21Florida sinkholes
-
Winterpark sinkhole - ? Increased with lowering of the water table
because water helped provide stability of rock