1. 1. 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.

   2. How many beds can be correlated across all three sections? _________

   3. How thick is the thickest stratigraphic section (or column of rocks)?
      (Note: We are not asking about this thickest BED. We are asking about the thickest SECTION.
      Also note that the scale goes from 0 to 70 meters.)

   4. 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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2. 1. Draw lines to correlate the two sections below. (USE A RULER!!.)
   2. Which section (A or B) contains an unconformity? __________

   3. Which units are missing from that section because of the unconformity? (Give rock types).

      _______________________________

   4. Label the position of the unconformity with an arrow and the word "unconformity".

   5. What type of unconformity is it? ________________________

   

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3. 1. Draw correlation lines between the three sections below. Note that the units vary in thickness in each section.
   2. What happens to the conglomerate in section C? Why is it not present in section A or B?
   3. Why does the thickness of the sandstone change from section A to section B?
   4. In which direction (west or east?) was the land?
   5. In which direction (west or east?) was deeper water?
   6. Label the right side of section C with arrows to illustrate transgresion (T) and regression (R).

   

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4. 1. Correlate the three sections below. (Note that the limestone unit is present only in sections A and B, and that it is much thinner in section B. It has thinned to the point where it is not present at all in section C.) This is called a pinchout.

      

   2. What type of sequence (transgressive? regressive? or transgressive-regressive?) is represented here, as indicated by the vertical sequence of facies?

      _______________________________________________________

   3. Label the column on the left with up-pointing arrows to indicate the part of the sequence which represents a transgression (T), and the part which represents a regression (R). Label the arrows T or R.

   4. These sediments were deposited in an ancient sea. Based on the rock types, which facies (not section) was deposited nearest to the mainland?

      _________________________________________________

   5. Which facies (not section) was deposited farthest from the land? ______________________

   6. In which direction (west or east) was the land? __________________________

   7. Explain your reasoning for your answer to question f. __________________________________________________________________________________________

      __________________________________________________________________________________________

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5. Using the data below from the western and eastern sections in the boxes below, do the following:
   1. Using a pencil and a ruler, draw two stratigraphic sections on graph paper using the rock type and thickness data provided below. (You may instead use the computer to draw your sections if you wish.)

      Use the appropriate lithologic symbols and the correct thicknesses, scaled correctly on the graph paper.

      Draw a horizontal line across the top of your paper to represent the ground surface. You will draw the sections below this line, as if they were drill core data (plotting each unit below the ground surface). The first unit listed in each section should be drawn at the top of that section, with all of the other units in order below.

      Draw the western section on the left and the eastern section on the right. Draw the sections about 4 inches apart with the tops on the same line.

   2. Locate the positions of all unconformities in the two sections (look for abrupt or erosional contacts in the section descriptions). Mark the positions of the unconformities on your sections by using a wavy line, and then, correlate the unconformities by extending the wavy line between the two sections. Label your wavy lines "UNCONFORMITY", for clarity.

   3. Correlate the two sections by drawing lines to connect the contacts between equivalent units. Remember that some beds may change in thickness laterally, whereas others may "pinch out", or be eroded away in one of the sections.

   4. Draw arrows labelled "T" and "R" along the outer side of both sections to indicate the part of the cycle which represents a transgression, and the part which represents a regression. (You will have to think about the sedimentary environments to answer this question.)

       

       

      Western section 100 ft Shale; dark gray, fissile; rare ammonoid fossils; lower contact abrupt - probably erosional. 40 ft Basalt with vesicles. (Lava flow). 35 ft Conglomerate; red to brown; no fossils. 100 ft Sandstone; white to pale red; dominantly quartz sandstone, very well sorted, rounded sand grains, cross-bedded; no fossils. 75 ft Dolostone; tan to light gray; a few gastropod fossils present. 40 ft Limestone; light gray; oolitic limestone. 25 ft Limestone; medium gray; fossiliferous limestone; tabulate corals, crinoids, and bryozoans abundant. Lower contact abrupt. 50 ft Conglomerate and breccia; brown to red matrix; no fossils. 75 ft Sandstone, with some conglomerate beds; brown to red; plant fossils and rare bones present. 100 ft Siltstone (brown to green) with rare coal beds; plant fossils and some bivalves. 50 ft Shale; green to gray or brown; trilobites and brachiopods present. ________ 690 ft TOTAL

       

      Eastern section 100 ft Shale; dark gray; fissile; rare ammonoid fossils present; lower contact abrupt - probably erosional. 40 ft Basalt with vesicles. (Lava flow). 75 ft Sandstone; white; dominantly quartz sandstone, very well sorted, rounded sand grains; cross-bedding present; fossils absent. 100 ft Dolostone; tan to gray; a few gastropod fossils present. 60 ft Limestone; light gray; cross-bedded, oolitic limestone. 25 ft Limestone; medium gray; fossiliferous limestone with abundant tabulate corals. 20 ft Limestone; dark gray micrite limestone; lower contact abrupt - apparently erosional. 65 ft Sandstone with local conglomerate beds; brown to red. 50 ft Siltstone (brown, green, and gray), with rare coal beds; plant fossils present. 40 ft Shale; gray to brown; fissile; trilobite fossils present. 100 ft Limestone; gray; micrite limestone; rare brachiopods and bryozoans. ________ 675 ft TOTAL

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