Download Which way*s up?

Which way’s up?
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What are these features?
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Where have you seen them before?
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How were they orientated where
you saw them?
In this outcrop, which way is “up”?
How were these features originally
orientated?
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How did this come to be?
So…what tilted these features? Is it tilted the same
everywhere?
Baraboo Quartzite on Highway 12, near Devil’s Lake. The ripple marks
are on a surface that tilts to the North at about 25 degrees.
Baraboo Quartzite near Rock Springs, WI. The surface with the
ripple marks is tilting to the south at about 89 degrees
Geologic Cartoon of the Baraboo area
Detailed Geologic section through Baraboo Region.
Note where Devil’s Lake and Abelman’s gorge is.
How did the Baraboo Quartzite get folded? The diagrams
below suggest a recent model. Subduction from the south!
In simple words, the complex world of the Baraboo
Quartzite is as follows
•Erosion of Penokean Mts
produces a great thickness of
sand which will ultimately be
the Baraboo Quartzite
•Quartzite is folded with the
collision from the south
during the Mapavai Orogeny
1650 Mya
Do the rocks seem to form a sequence?
• Where would you find
the oldest rocks?
• Youngest rocks?
• Are there different
kinds of rocks at
different outcrops?