07036 - 8 pages Within 48 Hrs Geology

CENTRAL PARK PROJECT

Rationale This project was designed with three main goals in mind: (1) Provide you with a clear and interesting link between the broad (at times seemingly disparate) skills taught in the course by exploiting local geology; (2) Provide the instructors an improved means of assessing your assimilation of those skills; and (3) Raise our awareness of the geology and geomorphology of arguably the most famous park in the world. Introduction

Central Park, established in 1857, is an 843-acre (341-ha) urban park in the hearth of Manhattan, New York City, bounded by 59th Street (Central Park South) to the south, 110th Street (Central Park North) to the north, 5th Avenue (Central Park East) to the east, and 8th Avenue (Central Park West) to the west. The park is a National Historic Landmark and hosts ~40 million visitors annually. Among these visitors, Earth scientists enjoy the abundance of rock outcrops in the park.

Being dominated by a single rock type, schist , a metamorphic rock with a sedimentary protolith, the bedrock geology of Central Park appears rather simple at first glance. Remarkably, however, there is in fact no consensus as to the exact age and origin of Central Park rocks. Indeed, scientists that have studied New York City geology have inconsistently and variably mapped Central Park rocks as part of two rock formations (see review by Puffer et al., 2010): (1) the Manhattan Schist/Formation — presumably of Cambrian–Ordovician (~500 Ma) age, with a protolith generally interpreted as pelitic sediment eroded off the North American continental craton and deposited on the continental shelf; and (2) the Hartland Formation — thought to be of younger (450–480 Ma) Ordovician age and to represent an exotic island arc terrane comprising volcanic rocks and volcanogenic sediments that was accreted to the North American craton during the Taconic Orogeny. The location of Cameron’s Line, an Ordovician suture fault thought to separate the autochthonous (locally derived) Manhattan Formation from the allochthonous (remotely derived, exotic) Hartland Formation, is highly disputed, but was proposed to run through Central Park (e.g., Taterka, 1987). This unresolved debate has significant implications for the tectonic evolution of the Northeastern US.

Central Park rocks also record the movement of glaciers that have covered the area in the past, most recently during the Wisconsin Glacial Episode from ~75 to 11 ka. Glacial erratics — boulders of various sizes dropped by receding glacier — and glacial striations or grooves — scratches or gouges cut into bedrock by rock fragments embedded at the base of the moving glacier — are visible throughout the park. A better understanding of the well-preserved glacial erosional landforms of Central Park can help reveal new details on the behavior of the Wisconsin glacier as it covered the area now occupied by New York City.

Our Central Park Project will thus tackle three research questions: (1) Do the rocks of Central Park belong to a single or multiple rock formations?; (2) What was the principal stresses direction during folding?; and (3) In what direction(s) were glaciers moving during the last glaciation? Early on in the course, you will formulate hypotheses directly linked to these questions and acquire field-based skills to conduct the field work necessary to help test these hypotheses. In the second part of the course, you will acquire data handling, analysis and presentation skills that will allow you to produce a professional quality deliverables (poster and report) in which you will present and discuss your findings following the scientific method.

In the field, your tasks will be to: (1) Make at least 10 measurements of the azimuth of glacial striations/grooves at a minimum

of 5 different outcrops. Performing additional measurements is encouraged. (2) Make at least 20 measurements of the trend of the rock foliation at a minimum of 10

different outcrops. Performing additional measurements is encouraged. (3) Make a detailed annotated sketch of an interesting outcrop of your choice, showing e.g.

glacial striations, folding, foliation, lithological contacts, etc. This should also include an example of height measurement, and so you should choose an outcrop with sufficient relief. A base map including the outline of outcrops will be provided. You must be able to plot your measurements on this base map for the poster and final report, and therefore you will need to know where you are and take good notes of it at all times.

PROJECT OUTLINE

Abstract An abstract is not a rewording of the conclusions, nor is it part of the introduction. Rather, it is a brief review of the most important points discussed in your paper. It must contain a statement of (1) background on the scientific problem/question(s) being studied; (2) the rationale/approach and main objective(s) of the research; (3) the methods used to accomplish the objective(s); (4) the main results of the research; and (5) conclusions about the implications of the research. Abstracts are placed first, but written last. Your abstract should be between 200 and 300 words.

Introduction

The Introduction must include: (1) Background information on the scientific problem; (2) the research questions being asked; (3) your hypotheses associated with the questions; and (4) a statement on the approach and objectives of your work/report. The introduction should be supported by significant research and therefore should include citations.

Methods

The Methods section must include: (1) A brief description of field methods and associated measurement uncertainties; (2) A brief description of the other data including sources being used in the report and the methods by which these data were acquired.

Results

Here you should describe (no interpretation) the results of your field work. This should include field observations and a description of the measurements obtained. Field results of the entire class should also be described. All of this should be supported by relevant figures (see below). The results should also present the mineralogical and geochemical data on schist samples that we have worked on in class, with associated figures.

Discussion

Here you should discuss your results and the class results in the context of the initial research questions. Do the results help you test your hypotheses? It is in the Discussion that you can interpret your observations and results. The Discussion should be supported by significant research and therefore should include citations.

Conclusion

The Conclusion serves to summarize the main results and conclusions of the report.

References

This section must include all references cited in the text provided in APA format and listed in alphabetical order (by first author last name).

Figures with captions (within or at the end of text)

Your report must include several figures following the guidelines and standards discussed in class. You must refer to those figures in the text, and each figure must include a detailed, self-explanatory caption with relevant data sources if any. Expected figures include, but are not limited to:

-Overview and detailed maps -Annotated field sketch and photographs -Histograms of glacial striations and foliation trend -Scatter plots of schist composition (data provided) More detailed guidelines are provided in the 200_Final_Report_Guidelines.docx file. References

Puffer, J. H., Benimoff, A. I., & Steiner, J. (2010). Geochemical characterization of New York City schist formations. New York State Geological Association.

Taterka, B.D. (1987). Bedrock geology of Central Park, New York City (Unpublished M.S. thesis), University of Massachusetts, Amherst, Massachusetts.

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