Research Areas
Working predominantly in the Precambrian Eon (4600 – 541 million years ago), my research draws from a variety of disciplines including sedimentology, stratigraphy, geochemistry, and petrology to focus on questions relating to early Earth processes. To date, my research involves both field and laboratory work, and seeks to determine and test hypotheses related to Precambrian earth-system evolution.
Controls on quartz precipitation mechanisms and isotope fractionation during diagenesis of Precambrian chemical sedimentary rocks like IF are not well constrained. Learn more
As chemical sedimentary rocks, the primary minerals in iron formations are thought to precipitate from seawater, and, if identified, may provide insight into geochemical conditions of Earth’s early oceans where nascent life is hypothesized to have first evolved. Learn more
Lab News
June 26, 2018
Interested in working in the lab for summer research? Currently recruiting!
We are currently recruiting for summer and fall undergraduate researchers! Interested in sedimentology and geochemistry? Read the article here: https://scse.d.umn.edu/earth-environmental-sciences-depa…
June 26, 2018
Congratulations to Anthony Wetzel and Kendall Johnson on their UROPs!
UMD undergraduate students Anthony Wetzel and Kendall Johnson just completed their 2017-18 Undergraduate Research Opportunity Projects (UROPs) and presented their research at the UROP Showcase. You ca…
November 11, 2016
Undergraduate Earth and Environmental Sciences major Stephen Hanson has been working since January 2016 to characterize the mineralogy and textures of several samples of ~1.9 Ga chemical sedimentary r…
October 10, 2016
Fall 2016: Looking for data for student projects / grants to apply for? Check these links out
https://earthdata.nasa.gov/ https://earthdata.nasa.gov/earth-observation-data http://www.earthcube.org/info/about http://www.cubesat.org/http://fc.umn.edu/ http://www.nasa.gov/offices/education/progra…
Projects
At present, projects in my lab focus on investigating the Precambrian silica cycle as it relates to the evolution of the crust-ocean system, when early microbial life radiated and evolved.
Publications
Brengman, L. A., Fedo, C.M. (2012). Origin of BIF-like jaspilite in the 2.72 Ga Hunter Mine Group, Abitibi Greenstone Belt, Quebec by metasomatic replacement of felsic volcanic rocks. Geological Society of America, Abstracts with Programs, Annual Meeting, Charlotte, N.C., v. 45, n. 7, p. 627.
Brengman, L. A., Fedo, C. M., Whitehouse, M. J. (2013). Silicon isotope composition of Archean cherts from >3.7 Ga to 2.7 Ga determined by Secondary Ion Mass Spectrometry (SIMS). Geological Society of America, Abstracts with Programs, Annual Meeting, Charlotte, N.C., v. 44, n. 7, p. 36.
Prentice, A., Jabeen, I, Webb, E., Banerjee, N., Ali, A., Brengman, L., Fedo, C. (2014). Dual Si and O Measurements Using IRMS-BrF5 Fluorination. Goldschmidt Conference, Sacramento, C.A., p. 1988.
Fedo, C. M., Brengman, L. A., (2014) Revisiting the stratigraphic setting of the ~3 Ga Buhwa Greenstone Belt, Zimbabwe. Geological Society of America, Abstracts with Programs, Annual Meeting, Vancouver, BC, v. 46, n. 6, p. 221.
Brengman, L. A., Fedo, C. M., Whitehouse, M. J. (2014) From source to sink: silicon isotope composition of bedrock, detrital quartz arenites, and siliceous precipitates from the ~3 Ga Buhwa Greenstone Belt, Zimbabwe. Geological Society of America, Abstracts with Programs, Annual Meeting, Vancouver, BC, v. 46, n. 6, p. 221.
Brengman, L.A., Fedo, C. M., Whitehouse, M. J. (2015) Micro-scale silicon isotope heterogeneity observed in hydrothermal quartz precipitates from the >3.7 Ga Isua Greenstone Belt, SW Greenland. Geological Society of America, Abstracts with Programs, Annual Meeting, Baltimore, MD, v. 47, n. 7, p.786.
Brengman, L.A., Larson, P., Hanson, S. (2016) A textural and mineralogical investigation of early diagenetic reactions in the ~1.88 Ga Biwabik iron formation, MN. Geological Society of America, Abstracts with Programs. v. 48, n. 7.
Brengman, L.A., Fedo, C. M., and Whitehouse, M. J., (2016). Micro‐scale silicon isotope heterogeneity observed in hydrothermal quartz precipitates from the> 3.7 Ga Isua Greenstone Belt, SW Greenland. Terra Nova 28.1: 70-75.
Brengman L. A., Heins W.A., Matthews J.A., (2016). Dissolution and Transformation of Provenance Lithotypes during Initial Sediment Generation with Application to Play-Element Prediction. ExxonMobil Upstream Research Company Research Application Report URC.2016.046, 136 p.
Brengman, L.A., Fedo, C.M., (2018). Development of a mixed seawater-hydrothermal fluid geochemical signature during alteration of volcanic rocks in the Archean (∼2.7 Ga) Abitibi Greenstone Belt, Canada. Geochimica et Cosmochimica Acta 227: 227-245.