Lead stable isotope ratios as indicators of soil age and human impacts

Lead (Pb) isotope ratios can often be used to trace sources of Pb in soils and water.   207Pb/206Pb and other Pb isotope ratios differ between the various sources of Pb in the environment.  For example, Pb deposited during the use of Pb gasoline additives often has distinctive Pb isotope ratios that can used to distinguish it from ordinary, naturally occurring Pb in soils.

This project aims to use Pb isotopes to trace the appearance of industrial Pb in soils close to Champaign-Urbana (in the “Critical Zone Observatory”).  The focus is not on Pb contamination; we seek to use the appearance of industrial Pb as an indicator of soil and sediment age- to distinguish pre-1940 soils from more recent ones.

This project involves:

  1. Lab work to implement methods for extracting and purifying Pb from soils and measuring Pb isotope ratios using the Multicollector ICP-MS.
  2. Measuring a series of soils.
  3. Interpreting results using information in the scientific literature regarding Pb isotopes in industrial emissions over time.

This could be either a senior thesis project or an undergraduate research project.

Supervisors:  Dr. David Grimley (ISGS), Prof. Tom Johnson, Dr. Gideon Bartov (Lab Manager)   contact:  tmjohnsn@illinois.edu

Paleoclimatology Undergrad research project: Fall 2016-Spring 2017

An undergraduate research project is available beginning Fall 2016 (or as early as summer 2016) with Dr. Jessica Conroy, Department of Geology and Department of Plant Biology.

The project will investigate the geochemistry and physical properties of lake sediment cores taken from pools and lakes at Cara Bianca, Belize, a Classic Maya site containing a water temple and settlement. Working closely with archaeologists, we will investigate the local climate and environment of this region over the past ~2,000 years.

Two new Undergraduate Research Projects available with Jared Freiburg at the ISGS:

  1. The origin of giant barite crystals in the Mississippi Valley, Iowa (would likely require sulfur isotope analysis and maybe fluid inclusion analysis work)
  2. The cause and significance of fluorescent/phosphorescent barite in the Mississippi Valley, Iowa (detailed LA-MICPMS elemental work on a variety of fluorescent and non-fluorescent barites)

Advisor: Jared Freiburg (ISGS) freiburg@illinois.edu

Paleobiology Undergraduate Research Projects ’16-’17

(1) Fossil insects from the Lower Cretaceous Crato Formation of Brazil

The Lower Cretaceous Crato Formation of northeastern Brazil is famous for the abundance and exceptional preservation of its paleobiota. The laminated limestones of the Nova Olinda Member yield and astonishing array of remarkably well preserved fossils, including a wide variety of vertebrates such as fish, turtles, lizards, crocodiles, pterosaurs, dinosaurs and birds, and a diverse flora including some of the earliest flowering plants. However, the most diverse and abundant component of the assemblage are terrestrial arthropods and, in particular, insects. This research project will involve the identification and description of exceptionally preserved fossil insects from the Crato Formation in the Illinois Natural History Survey Paleontology Collection, including a new species of diving beetle (Coleoptera: Dytiscidae).

Advisor: Sam W. Heads (INHS, swheads@illinois.edu), Jacalyn M. Wittmer (jwittm2@illinois.edu)

(2) Fossil earwigs (Insecta: Dermaptera) in Miocene Dominican amber

Earwigs (Dermaptera) are familiar insects characterized by a pair of prominent pincer-like forceps on the end of their abdomen. They are generally very rare in the fossil record, so well preserved specimens are extremely important to our understanding of earwig evolution. This research project will involve the study and formal description of two new species of earwigs preserved in Early Miocene amber from the Dominican Republic in the Illinois Natural History Survey Paleontology Collection. The work will involve amber preparation, advanced microscopy and digital imaging as well as training in formal taxonomic procedures.

Advisor: Sam W. Heads (INHS, swheads@illinois.edu), Jacalyn M. Wittmer (jwittm2@illinois.edu)

(3) Carbonate Sedimentology of the Middle Ordovician Kimmswick Formation

The Kimmswick Formation is a massive carbonate sequence that has until recently, been characterized by only a few sections. A new location in St. Louis, MO has completely altered the history of the Kimmswick in terms of depositional environment, stratigraphy, and paleoecology. Within the carbonate strata, an extensive crinoid-algal reef is exposed and draped by massive crinoid shoaling grainstones. This reef is quite possibly one of the oldest crinoid-algal reefs ever discovered. This research project will focus on the sedimentology of the Kimmswick by characterizing lithofacies and developing a regional stratigraphy. The research will involve field-based outcrop descriptions and collection of the carbonate strata in a sedimentological and stratigraphic context. The work will further involve thin section preparation, petrography, and cathodoluminescence microscopy.

Advisor: Jacalyn M. Wittmer (jwittm2@illinois.edu)

 

Geochemical tracers in archaeology: Preparation of samples from the Cahokia complex

Cahokia Mounds, in southwestern Illinois, was the site of a major “city” from ca. A.D. 1050 to 1350 with an estimated population of 40,000.  It was the largest prehistoric mound center in North America and is considered the center of what archaeologists call the Mississippian culture. Archaeological investigations aim to reveal the diet, health, demography, and biological relationships. The Illinois State Archaeological Survey (ISAS) Cahokia Project is a long-term, multi-disciplinary research project that seeks to identify factors that contributed to the rise and fall of the Cahokian polity.  ISAS is part of the Prairie Research Institute here at the U of I:
http://www.isas.illinois.edu/

This project will contribute to an effort that uses geochemical analyses (mainly stable isotope measurements) of both recently excavated and museum-derived human and animal remains from Cahokia and related regions, to offer new information on the health, diet, geographic origins, and genetic relationships of individuals living in, and interacting with, Cahokia.  See more about the Cahokia project at:
http://www.isas.illinois.edu/transportation_research/totc.shtml

This research project will involve working with ISAS archaeologists to extract small samples of teeth and bone using micro-drilling techniques, and prepare them for geochemical analyses.  The prepared samples will then be analyzed for carbon and strontium isotope ratios and, possibly, other geochemical variables.  The project will involve some training in these methods and ability to take part in analysis of samples.  The strontium isotope analyses are carried out in the Dept. of Geology geochemical laboratory; the carbon isotope analyses are done at the Illinois State Geological Survey.

Advisors:  
Dr. Kris Hedman, Assistant Director, Program on Ancient Technologies and Archaeological Materials, Illinois State Archaeological Survey (khedman@illinois.edu)
Dr. Tom Johnson, Professor of Geology (tmjohnsn@illinois.edu)

Surficial Geologic Mapping in the Wabash Valley

Geologic mapping is fundamentally discovery research: it provides baseline data for varied basic research and applied problems. The mapper always uncovers new and interesting questions. Over the past 5 years, surficial mapping in the lower Wabash Valley has contributed to the existing geologic framework with insights on neotectonics, Quaternary history, and floodplain evolution. There are opportunities for undergraduate and graduate students to map 7.5’ quadrangles or portions of quadrangles, that may constitute all of a Senior Thesis or part of a graduate research project. The work involves field investigations, laboratory study, and GIS analysis. Competitive funding through the USGS EDMAP program (http://ncgmp.usgs.gov/about/edmap.html) is sought in the fall, with fieldwork beginning in late spring; deliverables are due one year from the start date.

Advisers: Andrew Phillips (ISGS, aphillps@illinois.edu), Michael Stewart (stewart1@illinos.edu)

Passive seismic mapping of bedrock surface in the lower Wabash Valley.

Passive seismic method uses vibrations generated by waves crashing on distant coasts as well as passing traffic to characterize the subsurface. For Quaternary studies, sounding with PS has been demonstrated as a method for quickly mapping bedrock topography in a variety of terrains and bedrock lithologies. We have a Tromino device that we would like to use to test and supplement a draft bedrock topography map for the lower Wabash Valley and surroundings. I envision a project suitable for a Senior Thesis/Independent Study that could involve both theoretical and practical aspects of the method. A two-semester project would likely be best, although a particular well-prepared and motivated student might be able to do it in one. The project would involve 5-10 days of fieldwork, depending in part on the student’s level of interest. The product would include a report and map that would be presented at the North-Central GSA meeting in Champaign 2016. The project could even be a foray into Master’s-level research that could begin the following summer. Seed funding is available, but we would likely want to search for more.

Advisers: Andrew Phillips (ISGS, aphillps@illinois.edu), and Michael Stewart (Stewart1@illinois.edu)

Diagenetic History of the Mt. Simon Sandstones in the Illinois Basin

The study will focus on petrographic and geochemical properties of the Mt. Simon Sandstone in Illinois and its burial/cementation history. The study will examine and sample sedimentary cores for petrographic and geochemical analysis. The results of this study will be used to build up a database and detail different diagenetic trends within this sandstone. Experience in sedimentology and completion of GEOL440 would be an advantage. Project to begin Fall 2015, but with possibilities of summer 2015 work.

Advisors: Jared Freiberg (ISGS) and Jim Best

Diagenetic History of Carboniferous Sandstones in the Illinois Basin

The study will focus on petrographic and geochemical properties of thick Carboniferous sandstones in Illinois and their burial/cementation history. The study will examine and sample sedimentary cores for petrographic and geochemical analysis. The results of this petrographic study will be used to build up a regional database and create isocontour maps of data detailing different diagenetic trends within these sandstones. Experience in sedimentology and completion of GEOL440 would be an advantage. Project to begin Fall 2015, but with possibilities of summer 2015 work.

Advisors: Nathan Webb and Jared Freiberg (ISGS) and Jim Best

Regional Geology and Mineralogical Trends of the Carboniferous Cypress Sandstone

This project would work with the ISGS to construct regional cross-sections to correlate and define stratigraphic relationships of the Carboniferous Cypress Sandstone, an important hydrocarbon reservoir. The project would give experience in collecting samples from core to analyze for bulk and clay mineralogy, and updating regional maps of the Cypress sandstone by building on existing datasets. These mineralogical results will be related to sedimentological interpretations of the Cypress Sandstone and a large study examining the hydrocarbon characteristics of this sandstone. Experience in sedimentology and completion of GEOL440 would be an advantage. Project to begin Fall 2015, but with possibilities of summer 2015 work.

Advisors: Nathan Webb and Shane Butler (ISGS) and Jim Best