Transcript TODAY`S ANNOUNCEMENTS - NAU jan.ucc.nau.edu web server

ANNOUNCEMENTS
• Please read chapter 2 (the whole thing)
• Today:
– a little more on the exercise we started in
class. If you had an excused absence, you
got a copy over email. If you were not
excused, look on with a neighbor
– where earthquakes occur in different
tectonic settings and why
Turn on your clickers please…
What is the asthenosphere?
A. The rocky part of the upper mantle
and the crust
B. The semi-molten (jello) part of the
upper mantle and crust
C. The semi-molten part of the upper
mantle, but no crust is involved
D. Just the crust, with no mantle involved
Talk to your neighbor
• What answer did you give?
• How confident were you of that answer?
• Tell your neighbor one reason you gave
that answer.
• What do you think of your neighbor’s
reason for his/her answer -- makes
more/less sense than yours?
What is the asthenosphere?
A. The rocky part of the upper mantle
and the crust
B. The semi-molten (jello) part of the
upper mantle and crust
C. The semi-molten part of the upper
mantle, but no crust is involved
D. Just the crust, with no mantle involved
Take 5 minutes to complete the
graph from Friday’s exercise
• even if you don’t have your own copy, look
on your neighbor’s and be sure you
understand the questions that are on the
sheet
• by the way, they are real earthquake data
• the sheet (w/ questions on the back) is due
on Wednesday
• compare your graph with someone in your
group -- I’m not into dot-for-dot correlation,
I’m into you seeing the general shape
Your
Clickers
Please
What is the likely depth of
earthquakes at mid-ocean
ridges?
A. very shallow or very deep, but probably nothing in
between
B. only very shallow
C. only very deep
D. any depth is possible and likely
What is the likely depth of
earthquakes at mid-ocean
ridges?
A. very shallow or very deep, but probably nothing in
between
B. only very shallow
C. only very deep
D. any depth is possible and likely
How to describe a fault
• Envision a house
with a roof
• The line of the roof
is the strike -- where
two planes intersect
• The dip of the roof is
the same on either
side -- it’s the angle
of the roof