J. Patrick Harris


John Patrick Harris
Department of Geography and Geology
P.O. Box 2148
Huntsville, TX 77341

Phone: (936) 294-1452
Email: pat-harris@shsu.edu

GEOL 1305 Geologic Hazards
GEOL 1303 Physical Geology
GEOL 3304 Geochemistry
GEOL Petroleum Geology
GEOL 460/461 Field Geology

Low Temperature Geochemistry of Vertisols
Petrogenesis of Precious Metals in the V-Intrusive, Arkansas

Assistant Professor

There are two events that occurred in my early childhood to which I would attribute my career path: (1) When I was four years old, I found an arrowhead after digging in a ditch in our front yard. That made me start looking at the ground where I discovered many fascinating rocks and fossils. (2) When I was five, my family took a vacation to Wyoming. When I saw the Tetons, I asked my parents how those mountains got there? They told me that they didn’t know, but a geologist would know. That is when I decided that I wanted to be a geologist.

My fascination with geology has grown in the years since. My formal education (BS and MS University of Arkansas) involved field work with mixed siliciclastic-carbonate rocks which led to a job in the oil and gas industry. During my time in the oil industry, I developed an interest in sediment diagenesis. I returned to school (Ph.D. Texas A&M) where I studied diagenesis of the Delaware Mountain Group, which led to my interest in clay mineralogy.

My interest in clay mineralogy led to my current research where I use wet chemical techniques, differential scanning calorimetry, electron probe microanalysis, and scanning electron microscopy to investigate how changes in soil mineralogy affect chemical reactions of quicklime and cement in Texas soils.

Why is this research important? For example, Vertisols in Texas are stabilized with lime (CaO) or Portland cement that then react with the swelling clays to form new phases that are not susceptible to shrink/swell. The presence of sulfur in the soil can cause the lime and clay to form reaction products that can expand to a greater extent than untreated soil causing heaving problems with foundations and pavements.

My students and I do laboratory experiments that mimic reaction products observed in the field. The idea is to use this research to predict how soils will respond to various chemical stabilizers to minimize the effects swelling soils on infrastructure.

Similarly, I have been involved with evaluating the chemical weathering of salt dome caprock in northeast Texas. These rocks have a very unique mineralogy and can generate some exciting weathering products when exposed to the atmosphere and water. This rock has typically been used as road fill and aggregate with little success. Understanding the geochemistry of such rocks is important in evaluating their economic value.

I am also working on rocks from the V-Intrusive in central Arkansas to determine the origin of precious metals.

As a result of the interdisciplinary nature of my research, I have collaborated with soil scientists, geophysicists, geochemists, geologists, and engineers over the last several years.