Sedimentology explores the origin, transport, deposition and diagenetic alterations of the materials that compose sediments and sedimentary rocks.
We approach sedimentary rocks in two sequential stages:
- Description
Interpretation
Date: ______________
Lab Section: _________
Name: _______________________
To turn in at end of lab meeting.
I. Neatly fill in this table for at least 10 different sedimentary rocks.
Rock Name
Dominant
material
(clas., chem.,
org.)
and rock color
Resource/Use
Locations
Sed. structures (if any),
and other features
II. The Story of the Rock: You should describe and tell the “story of the rock.” Think about this
for each sample you examine. The starting point is the weathering of some preexisting rocks
(producing clastic and/or chemical sediment), or the growth of some life form (organic). Then
the material is eroded and transported (with many modifications along the way). Finally the
material is deposited at a final resting place, and lithified by burial and/or cementation.
JH 2/14/12
Stratigraphy and Lithologic Correlation
1.
a.
Draw lines between the three stratigraphic sections below to connect the geologic contacts
between similar lithologies. (USE A RULER!!.) Note that each vertical column is a
stratigraphic section.
Each lithologic unit can be regarded as a bed.
b.
How many beds can be correlated across all three sections?
c.
How thick is the thickest stratigraphic section (or column of rocks)?
d.
A bed of coal is present in sections B and C. How deep would you have to drill in section A (starting
at the top of the section, up near the letter A) to reach the buried coal seam?
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JH 2/14/12
2.
a.
Draw lines to correlate the two sections below.
b.
Which section (A or B) contains an unconformity?
c.
Which units are missing from that section because of the unconformity?
d.
Label the position of the unconformity with an arrow and the word “unconformity”.
e.
What type of unconformity is it?
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JH 2/14/12
3.
a.
Draw correlation lines between the three sections below.
Note that the units vary in thickness in each section.
a.
What happens to the conglomerate in section C? Why is it not present in section A or B?
b.
In which direction (west or east?) was the land?
c.
In which direction (west or east?) was deeper water?
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JH 2/14/12