GY 112L Lab Assignment 8 Paleozoic Lab 2

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1 Name: Grade /100 (+5 bonus) Percent: GY 112L Lab Assignment 8 Paleozoic Lab 2 Note: There are a lot of specimens to look at in this weeks lab. It is probably best for you to look at the physical specimens first and do the written questions last. This way if you run out of lab time, you ll be able to finish off the rest of the lab at home. Part 1: Fossils Sponges (Phylum Porifera; Cambrian to Recent) and Stromatolites (Archean Recent) Specimen 8-1a: Astraeospongia sp. (Silurian); Specimen 8-1b: stromatolite (Paleozoic); Specimen 8-1c: Corynella sp. (Cretaceous) Why do sponges like specimen 8-1a have spicules? Specimen 8-1c is an excellent fossilized sponge. What characteristic(s) tell you that it is a sponge? (hint: examine the specimen with your hand lens) [3 points] Specimen 8-1b is a fine example of a Paleozoic stromatolite. Where are the oldest stromatolites on the Earth found? (Refer to your web notes for the answer). [3 points] Corals: (Phylum Cnidaria; Cambrian to Recent) Specimen 8-2a: Streptelasma sp. Ord.- Dev., Specimen 8-2b: Heliophyllum sp. Dev., Specimen 8-2c: Favosites sp. Ord Perm., Specimen 8-2d: unknown tabulate coral HY-73 Which specimen(s) are colonial corals? [3 points] Which specimen(s) are solitary corals? [3 points] A possible internet research question: How do modern coral propagate? [5 points] i

2 Bryozoans (Phylum Bryozoan, Ordovican-Recent) Specimen 8-3a: Dekayella sp., Ord., Specimen 8-3b: Hallopora sp. Ord-Dev., Specimen 8-3c Archimedes sp. Miss-Perm. Some Bryozoans are twig like while others are lacy; however, they all share some common charcteristics. What are they? [5 points] Specimen 8-3c is called Archimedes? Why is this a good name for this beastie? (Hint who was Archimedes and what did he do?) [5 points] More Drawing 101 Draw any Two of the organisms in the lab today. Use the box below and the one at the top of the next page for your sketches. Remember to use pencil, and add shading where possible. Be sure to add scales (use cm not inches) to your diagrams. If you are unclear as to how you go about doing this, ask us. [10 points each; 20 total] Name of Specimen: Specimen Number: Scale ii

3 Name of Specimen: Specimen Number: Scale Want some additional credit? Draw another (different) beastie for 5 bonus points Name of Specimen: Specimen Number: Scale iii

4 Part 2: Niagara Falls Rock Suite Background: The Niagara Falls area (southern Ontario, Canada and northern New York State; Figure 8-8) is underlain by a combination of siliciclastic and carbonate rock units that range in age from the Ordovician to the Silurian. There are numerous facies changes within the strata and even a few unconformities. The neat thing about the rocks is their exposure. Rocky outcrops can be found all around the Niagara Falls area. In fact, you can trace individual beds for a couple of hundred kilometers from northern New York State to the tip of the Bruce Peninsula in Ontario. For this lab, you will see rocks, maps, and stratigraphic sections. Stratigraphy. Figure 8-9 at the top of the next page is a stratigraphic column for the northern portion of the United States (Including parts of Canada) from Michigan to New York. It covers the Cambrian-Silurian intervals of geological time. It initially looks pretty complex, but do not panic! It isn't all that difficult to interpret once you get your eyes in focus. The extreme left columns are time intervals. Here you will spot your old friends the Cambrian (Camb.) Ordovician and Silurian. You will also see the divisions Early, Middle and Late. A lot of the other terms (Niagaran, Llandoverian etc.) are epochs or other divisions that we do not have to worry about in GY 112/112L. The rest of the columns relate the stratigraphy at specific areas. Figure 8-8: Paleogeographic map of southern Ontario, New York and Pennsylvania during the Wenlockian Epoch. From Cheel, R.J., Sedimentology and depositional environments of Silurian Strata of the Niagara Escarpment, Ontario and New York. iv

5 Figure 8-9: A portion of Paleozoic stratigraphy covering the area around Niagara Falls From Cheel, R.J., Sedimentology and depositional environments of Silurian Strata of the Niagara Escarpment, Ontario and New York. The Niagara region is the second column from the right. The names that occur in the rows within each column are formation etc. names. Refer to the Niagara area column to answer the next 6 questions. What age is the Rochester Formation? [3 points] What age is the Queenston Formation? [3 points] To which group does the Whirlpool Formation belong? [3 points] What happens to the Queenston Formation from Windsor-Sarnia to W. New York? [4 points] v

6 What do you think the black areas represent across the stratigraphic columns? [4 points] Why are the Silurian black areas thicker at Algonquin Arch than at other geographical regions in the area? (Hint: Think time and topography before you ask for help). [4 points] Rock Suites. Figure 8-10 to the right is a sedimentary section through the rocks that underlay Niagara falls. Rock samples 8-4 through 8-6 (locations shown on the figure) come from this section. Figure modified from Cheel, R.J., Sedimentology and depositional environments of Silurian Strata of the Niagara Escarpment, Ontario and New York. 8-6 Rock Specimen 8-4: Rochester Formation. What is class of sedimentary rock is this specimen? [2 points] 8-5 What is the name of this sedimentary rock [3 points] Rock Specimen 8-5: Gasport Formation. Some 8-4 people clump this formation into the Lockport Group. Regardless of what you call it, this rock and the Rochester Formation below are the reason why we have Niagara Falls. What properties of the Gasport/Lockport Formation coupled with the stratigraphic relationships between the formation helped to produce Niagara Falls? (Hint: consider the stratigraphy in Figure What are the black layers composed of and how do they differ from the white layers?) [3 points] vi

7 Rock Specimen 8-6: Goat Island Formation. This is a fine-grained sedimentary rock with round chert nodules. What is class of sedimentary rock is this specimen? [2 points] What is the name of this sedimentary rock [3 points] Look at the rock with your hand lens. Geologists often use the term "sucrosic" to describe dolostones. Why do they do this and do you agree with its usage here? [3 points] The Falls. The figure below is a cartoon of Niagara Falls viewed from the air. From Cheel, R.J., Sedimentology and depositional environments of Silurian Strata of the Niagara Escarpment, Ontario and New York. Given that the Peace River Bridge is 500 m long, determine the rate of retreat of the Horseshoe (Canadian) Falls from: 1378 to 1678: m/year [3 points] 1842 to 1927: m/year [3 points] vii

8 Name: Last Question: Without Niagara Falls, it s unlikely that the cities of Niagara Falls (one in Canada, the other in the US) would ever have become the Honeymoon Capitals of the world. No hotels would have located here. All the wax museums, strip clubs and other el- d to go somewhere else. With the exception of cheapo tourist attractions would have ha Orlando, Las Vegas and other existing tourist traps, where might these eyesores have gone and why? (Note: the funnier your answer, the better your grade). [10 points] Notes viii