For years I've been trying to use and modify the rock correlation labs from the state and still my students struggled. I finally sat down and created one that, though similar to those out there, is more straightforward and comprehensive.
We invite faculty to participate in an upcoming, fully-funded workshop, with both classroom and field components, focusing on using the IGUaNA curriculum modules in introductory level courses. These materials feature urban environmental, engineering, and forensic questions that can be answered using near-surface geophysics.
Alessandro Grippo, Ph.D.A key to lab 14 (Earth History), Fossil Indicators of Age, Environment, and Correlation answers to Lab 12 questionsLast Updated • November 30, 2016 Fossils and Age DeterminationsReview these materials and know them for the testquestion 1, page 161from bottom to top: C, O, S, D, Mor Cambrian, Ordovician, Silurian, Devonian, Mississippianquestion 2, page 161You shoudl draw the respective ranges for fossils F-1 and F-2. Ranges go from the bottom of the oldest Period to the Top of the youngest Period, and are indicated by a straight line closed, top and bottom, by a horizontal mark.F-1 (trilobite): C, O, SF-2 (crinoid): S, D, MThe two fossils only overlap during time S (Silurian)question 3, page 161Region IV only contains F-1F-1 is found alone (without F-2) only during the Cambrian and the OrdovicianThe rocks in unexplored region IV were deposited during the Cambrian and the Ordovician Periodsquestion 4, page 161Region V contains both F-1 and F-2These two fossils ranges overlap only during the SilurianThe rocks in unexplored region V were deposited during the Silurian Periodquestion 5, page 162The only time when Fossil F-1 is found by itself is during times C and O (Cambrian and Ordovician)question 6, page 162The only time when Fossils F-1 and F-2 are found together is during time S (Silurian)question 7, pages 162 and 163skippedBiozones and BiostratigraphyReview these materials and know them for the testquestion 1, page 164skippedquestion 2, page 165 skippedA Graphic Method of CorrelationInterpretation of an Outcrop in Southern IllinoisInterpretation of an Outcrop in Central IllinoisFossils and PaleoenvironmentsReview these materials and know them for the testquestion 1, page 169Benthonic and planktonic foraminiferaquestion 2, page 169Organisms with soft parts only, no shells or hard, mineralized parts or structuresquestion 3, page 170Shells of foraminifera can be retrieved intact from cuttings, the rock fragments obtained during drilling operations. If one knows at what depth certain benthic foraminifera live, one can estimate the ancient depth of the ocean bottom. If several wells are drilled, it is possible to observe trend or directions towards ancient shallow-waters areas and shorelines.The Habitat of Marine LifeReview these materials and know them for the testquestion 1, page 172 (left column)A bathymetric change refers to a change in the depth of the water column. The question is asking if, based on the kind of fossil you find, you can indicate how the depth of that ancient ocean changed.Since calcareous sponges and algae live in shallow waters (on the shelf) and siliceous sponges and cephalopods instead live in deeper waters, you can safely say that the sea level has been rising (that is the answer to the question)question 2, page 172 (left column)Because cephalopods and planktonic foraminifera live in the water column and not at the bottom of the ocean, so they are not tied to a specific depth of the ocean bottomquestion 3, page 172 (left column)The layer was deposited in shallow waters, on the shelfquestion 4, page 172 (left column)from page 170: "The forms of life found in the neritic-benthic zone require at least some light. That biologic requirement is readily met over most of this shallow zone where sunlight penetrates all the way to the ocean floor"question 5, page 172 (left column)Because during low tides the ocean bottom might become exposed and sea creatures can remain in the water saturated zone by digging deeper and deeperquestion 1, page 172 (right column)The four definitions are listed in the book in the same order, from top to bottom, in which they should be inserted in Figure 12.11, page 172question 2, page 172 (right column)There are three unconformities (all three are disconformities). Draw the arrowsMostly, there is a sharp change in fossil (and lithology, but that is not as important), rather than a gradual onequestion 3, pages 172 and 173 (right column)Paleozoic (for corals, figure 10.27, page 117; bryozoans, 10.29, page 119; brachiopods, 10.31, page 121; ferns and scale-tree fossils, 11.43, page 157)Cenozoic (woolly mammoth only existed during the Quaternary, which is part of the Cenozoic)Mesozoic (for angiosperms, like oak, figure 11.41, page 155)Invertebrate Trace FossilsReview these materials and know them for the testBack to Top | Back to Labs | Back to Home Page
Combining the field monitoring results of a deep-buried tunnel in Chongqing, the dynamic characteristics of the surrounding rock system under high in situ stress was analyzed by phase space reconstruction, calculating correlation dimension, Kolmogorov entropy and largest Lyapunov exponents. Both the Kolmogorov entropy and largest Lyapunov exponents show that the surrounding rock system is a chaotic one. Based on this, a local model was applied to predict surrounding rock displacement, and a nonlinear dynamic model was derived to forecast the interaction of the surrounding rock and support structure. The local method was found to have an extremely small total error. Also, the nonlinear dynamic model forecasting curves agree with the monitoring ones very well. It is proved that the nonlinear dynamic characteristic study is very important in analyzing rock stability and predicting the evolution of rock systems.
ABSTRACT: We evaluated the utility of whole-rock amino acid racemization as a method for the stratigraphic correlation and dating of carbonate sediments in the Hawaiian Islands. D-alloisoleucine/L-isoleucine (A/I) ratios were determined for carbonate sand and sandstone samples from 25 localities in the archipelago. The superposition of A/I ratios within stratigraphic sections and the regional concordance of ratios within geological formations support the integrity of the method. To correlate the A/I ratios with an absolute chronology, comparisons were made with previously published uranium series dates on corals and with [C.sup.14] dates on carbonate sand and organic material, including several new dates reported herein. The A/I mean from four marine isotope stage (MIS) 5e U-series calibration sites was 0.505 [+ or -] 0.027 (n = 11), and 12 "test sites" of previously uncertain or speculative geochronological age yielded an A/I mean of 0.445 [+ or -] 0.058 (n = 17). Similarly, extensive Holocene dunes o n Moloka'i and Kaua'i were correlated by a mean A/I ratio of 0.266 [+ or -] 0.022 (n = 8) and equated with a [C.sup.14] bulk sediment mean age of 8600 yr B.P. Our results indicate that the eolian dunes currently exposed in various localities in the Islands originated primarily during two major periods of dune formation, the last interglacial (MIS 5e) and the early Holocene (MIS 1). MIS 5e and MIS 1 A/I ratios from the Hawaiian Islands show close agreement with previous whole-rock studies in Bermuda and the Bahamas. We discuss these results in terms of their relevance to models of lithospheric flexure and to imposing constraints on the time frame for the extinction of fossil birds. 2b1af7f3a8