Introduction:
We want to show how the size, abundance, and distrubution of species reveals the conditions at the time of deposition. Previous research discusses the Ordovician environment based on long standing asumptions without discussing how such conclusions were reached. We want to investigate for ourselves and show what our evidence reveals about the Ordovician environment.
According to R.H. Osbourne, his data concludes that Bryozoans and Brachiopods lived in similar types of environments. The habitat includes all marine environments except smooth sand or muddy bottoms because they need a firm, clean surface to attach to. Evidence has also shown that some species of Brachiopods and Bryozoans require clear water in which the sediments are unstirred. Most modern Brachiopods live in areas were the bottoms are not distrupted by strong currents because they are not physiologically adapted to handle large amounts of sediment accumulation (Osbourne, 1966).
We hope that the data we collect depicts this type of environment, and depositional characeristics that we predict. We predict and hypothesize that the fossils we find in the Liberty Formation will show two things. First, during the late Ordovician, Ohio was near the equator under a tropical sea, and second, deposition occured deeper offshore waters.
Research and design methods:
We plan to make two trips to study the Liberty Formation at Route 1 in Brookville, IN. At each visit, our sample area will include two randomly selected areas. They will be one foot wide and extend vertically the entire height of the formation. We will then use stakes and rope to mark off cubed sections every two feet apart as you go up the formation. Sample spots will be noted by approximate elevation within the formation, judging from our starting point at ground zero elevation.
At each sample location, we will count the number, abundance, and size of each individual species on the surface of the formation. We will look at the distribution and the general orientation of the fossils. Finally, we will generally take notice of the soil and rock surrounding the fossils. From the data we collect, we hope to determine the environment in which these individuals lived.
Analysis:
The data will be used to statistically calculate numerous things. First we will calculate the mean, median, and mode for each species. We will also calculate the standard deviation and varience, if the data requires. Then, most importantly, t-tests will be performed. This test will tell us whether or not two samples come from the same population. We can use this to compare between different species, or between different elevations.
Data Sheet:
Table 1: Species Abundance (depicts top horizontal row of table)
Sample #/ Elevation/ # of / # of / # of / # of / # of / # of
Brachs Gastros Bryos Trilos Cephs Pelecypods
Table 2: Brachiopods
Size: Large (> 10 cm) ? Total pieces: ?
Medium (around 5 cm) ? Whole pieces ?
Small (< 3 cm) ? Fragmented pieces ?
Table 3: Bryozoans
Number seen
Branched ?
Encrusting ?
Sheet Colonies ?
Flow Chart:
We plan to meet every Sunday to correlate research, data, charts, etc. and also make a progress report on the web. We plan to make our sampling field trips to the roadcut on November 5th and November 22nd. Then, November 13th, we are setting up our spread sheets, and entering our first set of data into the computer. We will also get a preliminary distibution of our findings. On November 20th, we will have the research and background section of our paper complete. On November 25th, t-tests and all data sheets will be complete. November 26-30th, we will analysize our data in detail. Finally on December 1st, our individual papers and group presentation will be complete. We will finish by editing and practicing our presentation.
Bibliography:
Feldmann, Rodney M.; Hackathorn, Marianne. "Fossils of Ohio", bulletin 70. Ohio Division of Geological Survey. 1996.
Frey, Robert Charles. "The Biostratigraphy of the Upper Richmond Group (Upper Ordovician), Franklin County, IN." Miami University Department of Geology Thesis Paper, Copyright 1976.
Maurer, Robert James. "The Clssification of Bedding Contacts in the Richmondian Stage (Upper Ordovician) of the Cincinnatian Series" Miami University Department of Geology Thesis Paper, Copyright 1974.
Osbourne, R.H. "Bedrock Geology and Limestone Petrology of Eastern Hamilton County, OH" Ohio State University Department of Geology Dissertation Paper, Copyright 1966.
Ross, Robert M.; Allman, Warren D. "Causes of Evolution: A Paleontological Perspective" University of Chicago Press: Chicago, IL, Copyright 1990.
Spencer, Edgar Winston. "Basic Concepts of Historical Geology" Thomas Y. Crowell Co.: New York, Copyright 1962.
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