Geology and Mineralogy of Clays
"How many clay flakes can you stack on the head of a pin?"...Answer: At least 10,000, and each may have a different story to tell about the geologic history of the sediment or soil from which they were derived. In addition, the chemical and structural details of the flakes create properties that govern their use for isolation of wastes or utilization in industry. A general goal of my research is to unravel the geologic history and evaluate the utilization of clay-rich sediments and soils.
Water Quality and Waste Isolation
Ion exchange processes and large surface area per unit mass give clays a prominent role in environmental geochemistry. Activities in this focus area utilize actual field data and models, such as PHREEQC, to predict the behavior of engineered and natural waste isolation barriers, or to explain the evolution of major elements in groundwater migrating through soils and sediments. The general goal is to sustain or improve groundwater quality.
XRD Method Development
The primary tool for the identification and quantification of clay minerals and other fine-grained materials is X-ray powder diffraction. Research in this area is concentrated on formulating computer simulation models for XRD patterns and "groud-truthing" the results from real samples with other analytical techniques such as scanning electron microscopy, electron microprobe analyses, FTIR, and selective chemical extraction procedures. The goals are to obtain more qualitative information and better quantitative analyses of natural and synthetic materials.
Computer Assisted Learning and Teaching
This title is so descriptive that it probably needs no further comment. Information technology advances are occurring at a rapid pace. My goal is to incorporate them in my teaching when they advance student learning.
Earth System Science content and field experiences for in-service elementary and secondary teachers present special opportunities to combine research and teaching and to improve science education. Recruitment of under-represented ethnic groups to pursue careers in geoscience is an allied special project.
Shaheen, S. A., Zhang, C., Mohanty, R. C., Murugaiah, A., Raman, A., Grenier, C. G., and Ferrell, R. E. Stabilization of iron-rich NdFe13-xBex compounds. Journal of Applied Physics. 89: No. 1, 504-506. 2001.
Aparicio, P., Ferrell, R. E., and Galan, E. Aplicacion de la Modelizacion Matematica a los Diagramas de DRX de la Caolinita para Mejorar el Calculo de "Indices de Cristalinidad", in: Arenzana, J. Z., del Valle, A. J. R., Garcia, M. V. M., (eds.) Integracion Ciencia-Tecnologia de las Arcillas en el Contexto Tecnologico-Social del Nuevo Milenio. Sociedad Espanola de Arcillas,Malaga, 21-29, 2000.
Emery, E. F., Junk, T., Ferrell, R. E., De Hon, R., and Butler, L. G., Solid-State 2H MAS NMR Studies of TNT Absorption in Soil and Clays., Environ. Sci. Technol., 35, 2973-2978, 2001.
Aparicio, P., and Ferrell, R. E. An application of profile fitting and CLAY++ for the quantitative representation (QR) of mixed-layer clay minerals, Clay Minerals, 36, 501-514, 2001.
Ferrell, R. E., Aagaard, P., Forsman, J., Greenwood, L., and Zheng, Z., Application of a geochemical transport model to predict heavy metal retention (Pb) by clay liners. Applied Clay Science, 21, 59-66, 2002.
Ferrell, R. E., Forsman, J., and LeBlanc, W. S., Use of Multimedia to Enhance Clay Mineralogy Laboratory Activities. In; A. Rule and S. Guggenheim, (eds.) Teaching Clay Science (2002) CMS Workshop Lectures, Volume 11, 114-121.