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Tombstone Weathering Lab. Preparation. Reading on Weathering Processes Lecture on Weathering Processes Chemical Physical Class-generated list of factors controlling weathering rates. Goals. Examine weathered surfaces and infer weathering processes
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Preparation • Reading on Weathering Processes • Lecture on Weathering Processes • Chemical • Physical • Class-generated list of factors controlling weathering rates
Goals • Examine weathered surfaces and infer weathering processes • Make qualitative and quantitative measures of weathering extent • Estimate weathering rate • Deal with noisy natural data • Generate hypotheses on controls of weathering extent in addition to time
Cemetery with Recognizable Consistent Lithology and Shape of Headstones
Field Trip Steps • 5 minute intro from owner – Jewish section pointed out & off-limits • 10 minutes observations of weathering in a small area • 10 minute group discussion of weathering processes
Field Trip Steps • 5 minute demo on using calipers
Group Work • Identify a headstone (shape, readable, sandstone) • Measure width of top and bottom of stone • Determine visual weathering class • Other observations • Spend ~60 minutes
Data Analysis • Scatter plots of age and VWC and change in thickness • Estimate weathering rates • Class discussion about scatter: “How good do we expect it to look?”
Hypotheses on other controls • Class brainstorming on other factors • In-class writing – pick a hypothesis, describe how you could test it • Interesting idea: aspect as a control
Practical Considerations • Finding the right cemetery – uniform lithology is key, uniform shape is good • Cemetery permission (hard to find people in charge for small, country places) • Winter is OK (if not too cold) • Calipers should be more than 6” long • Engineers may need help to recognize sandstone