Contact us to inquire about graduate student opportunities in our group

TTU Clay Mineralogy Group

Linking Mineral Science to Geological Processes 



Clay minerals are encountered in a variety of geological materials and, as such, represent an important line of research. Due to the environment in which they appear, that is constantly crisscrossed by man’s activity, clays are studied from different aspects of human endeavor (e.g. oil and petroleum research, environmental studies, radioactive waste storage). Clay minerals are normally present whenever water and rock meet. They are common products of weathering, and may hold a key role in the diagenetic evolution which takes place in sedimentary basins during sediment burial. Clay mineral presence in hydrocarbon reservoirs largely affects the efficiency of petroleum production, and they are important in hydrothermal and weathering ore-forming processes. Our research is, therefore, focused on different geological environments, starting with the deep sedimentary basins through weathering and soil profiles where we investigate the structure, crystalochemistry, and reaction mechanisms leading to the formation of clay minerals, which is pivotal to fully understand the geology of these environments and how they came into being. X-ray diffraction is the foundation of clay science and we have recently acquired a Bruker D8 Advance diffractometer. Other methods used in our research are scanning and transmission electron microscopy, spectroscopic chemical analyses, K-Ar dating and organic petrography, which are done either elsewhere at TTU, or in our partner laboratories.


Sedimentary Basins

Clays generated by surface weathering and shallow diagenetic processes are transformed into mature clay mineral assemblages in mudrocks found in sedimentary basins. During metamorphism, the release of alkalies and boron from clay minerals generates magmas that are subsequently weathered and recycled, representing the magma-to-mud pathway of the clay cycle. Diagenetic reactions in sedimentary basins are driven towards higher thermodynamic stability at a rate which is controlled by kinetics of the mineral reactions. Since the 1970s, clay minerals have been widely studied for diagenesis and quality prediction of conventional reservoirs. Modern analytical tools enable a precise quantitative and qualitative characterization of nano-pore and mineralogy of fine grained shale creating a new era of studying clay minerals for facilitating unconventional reservoir exploration. We are presently investigating Paleozoic mudrocks from the Anadarko and Permian basins of the American Mid-Continent to find physico-chemical clues that outline the mechanisms of clay mineral evolution in deep-buried shaley strata.  

Photo by B. Segvic (Bituminous Woodford Shale, Arbuckle Mts., Oklahoma, U.S.A.)

Soils, paleosols, and weathering profiles

Processes of weathering and soil formation are the best indicators of the present environment of the Earth's land surface. This information can be further used to interpret past environments, which have produced soils now preserved as paleosols. The surface environment of the Earth may now be undergoing rapid change, which makes the study of paleosols even more attractive, as they provide evidences of analogous changes in the Earth's past. At the moment we are working on alteration profiles of Neogene volcanoclastic material from the Dinaride Lake System of SE Europe, while another ongoing project in our group aims to link the clay mineralogy and geochemistry of paleosols from the Southern High Plains of West Texas with the Quaternary climatic changes.  

Photo by L. Badurina (Fe-Mn nodules, Black Water Draw Formation, West Texas, U.S.A.)

Clays as ceramic raw material

Clay minerals were utilized in the production of archaeological pottery since the dawn of civilization. Pottery is one of the most important lines of material evidence for the archaeological enquiry of ancient societies. Once produced, ceramics are indestructible and often found in great quantities at archaeological sites. Ceramics record past cultural interaction, ranging from everyday activities such as food preparation and consumption to more sacred rituals such as religious worship and funerals. At present we are studying the clayey raw material used in the Prehistoric pottery production in the Upper Rhône Valley, Switzerland. This is a collaborative research with the colleagues from Switzerland and France; more can be found here.   


Photo showing mineral mapping of Prehistoric pottery from Valais, Switzerland. Green color denotes clay minerals. Image 2x1 cm. Courtesy of D. Carloni, University of Geneva


Our Team

Assistant Professor

Branimir Šegvić

M.S. University of Zagreb, 2003

Ph.D. University of Heidelberg, 2010



Ph.D. Candidate & Research Assistant

Giovanni Zanoni

B.S. & M.S. University of Geneva, 2013, 2015


Giovanni's Ph.D. project is focused on diagenesis of the Anadarko Basin shale (Oklahoma, U.S.A.). Using state-of-the-art techniques he aims to unveil clay mineral origin and phase transitions that had taken place in the middle Paleozoic strata during the burial of the basin. His research will ultimately help to constrain basin's thermal structure and characteristics of unconventional Anadarko reservoirs.    

M.S. Student & Teaching Assistant

Colton Mallett

B.S. Texas Tech University, 2018


Colton studies paleosol profiles within the Black Water Draw Formation of Southern High Planes of Texas. The aim of the project is to investigate clay mineralogy and geochemistry of the Formation in order to add to the discussion on the Quaternary climate evolution across the Mid-Continent. 

Ph.D. Student & Teaching Assistant

Luka Badurina

B.S. University of Zagreb, 2018

M.S. Texas Tech University, 2019


Luka's project deals with the alteration products of Neogene tuffs dispersed within the Dinaride Lake System in SE Europe. Based on mineralogical and geochemical clues Luka will report on the provenance and dynamics of Late Neogene volcanism in the region. Another aspect of his research is to document and understand the role of microrganisms in the volcanic glass transformation mechanisms in diagenetically altered lacustrine pyroclastites. 

Ph.D. Student

Hunter Green

B.S. Wayland Baptist University, 2013

M.S. Fort Hays State University, 2016


Hunter's doctoral project has a focus on the late Paleozoic shale of the Permian basin of Texas. He is studying the clay mineral transformation indices along with the type and maturation degree of organic matter aiming to yield a robust diagenetic model of this prolific basin. 

M.S. Student & Teaching Assistant 

Bruno Mravlja

B.S. University of Zagreb, 2017


The middle Triassic volcanism of SE Europe coincides, both spatially and genetically, with the formation and further disintegration of Apulia, on top of which the Adriatic-Dinaride carbonate platform resided during Mesozoic time. Bruno investigates the Triassic volcano-sedimentary successions in order to report on the type and significance of hydrothermal and diagenetic alterations.  

M.S. Student & Teaching Assistant (Fall 2020)


Emily E. Doyle

B.S. Salem State University, 2020


Emily's project will focus on the ceramic material culture of the Iron Age    and Hellenistic communities of Eastern Adriatic. She will be looking at how    the interaction between two communities affected raw material (clay) procurement practices, the firing technology, and other aspects of pottery manufacture. Her project is in collaboration with Dr. M. Ugarković, Institute of Archaeology, Zagreb. 

Undergraduate Researcher 

Daniel Lavery


Daniel studies the mineralogy of late Paleozoic Woodford Shale from the Arbuckle Mountains in Oklahoma in order

to understand the hydrocarbon migration patterns in mudstones. Daniel is the TTU Honors College supported scholar.     


Undergraduate Researcher

Kevin Byerly


Kevin works on the mineralogy and geochemisty of playa lakes of West Texas with a goal to add to the understanding of their formation and evolution during Pleistocene. 

Our Alumni

Former Undergraduate Researcher ​

Moustapha Diaby

Moustapha investigated clay mineral parageneses of the Quaternary Black Water Draw Formation of West Texas in order to assess their susceptibility to climatic changes since the last glacial period in North America. Moustapha received a recognition for the best student poster at the TTU Geoscience Research Day 2018.   

Former M.S. Student ​

Jordan Coe

Graduated in December 2019 

Jordan's master project focused on the diagenesis of the Pennsylvanian clastic reservoirs of the Anadarko Basin

in Oklahoma, USA. PDF of the thesis is avaliable here.   



Journal Papers

Segvic, B; Zanoni, G; Moscariello, A ‘On the Origins of Eogenetic Chlorite in Verdine Facies Sedimentary Rocks’// Marine and Petroleum Geology (2020), DOI: 10.1016/j.marpetgeo.2019.104064 link here


Khadka, SD; Jayawickrama, PW; Senadheera, S; Segvic, B ‘Stabilization of highly expansive soils containing sulfate using metakaolin and fly ash based geopolymer modified with lime and gypsum’, DOI: 10.1016/j.trgeo.2020.100327 // Transportation Geotechnics (2020) link here

Tarokh, A; Kim, K; Zhu, X; Makhnenko, RY; Popovics, JS; Segvic, B; Sweet, DE ‘Influence of CO2 injection on the poromechanical response of Berea sandstone’, DOI: 10.1016/j.ijggc.2020.102959 // International Journal of Greenhouse Gas Control (2020) link here

Monson, CC; Sweet, DE; Segvic, B; Zanoni, G; Balling, K; Wittmer, JM; Ganis, GR ‘The Late Ordovician (Sandbian) Glasford Structure: A marine-target impact crater connected to the ‘Ordovician meteor event’’// Meteoritics and Planetary Science (2019), DOI: 10.1111/maps.13401  link here


Slovenec, Da; Segvic, B; Halamic, J; Gorican, S; Zanoni, G ‘An ensialic volcanic arc along the northwestern edge of Paleotethys? – insights from the Mid-Triassic volcano-sedimentary succession of Ivanščica Mt. (northwestern Croatia)’ // Geological Journal (2019), DOI: 10.1002/gj.3664

Leila, M; Moscariello, A; Segvic, B ‘Depositional facies controls on the diagenesis and reservoir quality of the Messinian Qawasim and Abu Madi formations, onshore Nile Delta, Egypt’// Geological Journal (2019), 54(3), 1797-1813, DOI: 10.1002/gj.3269 link here

Segvic, B; Slovenec, Da; Altherr, R; Babajic, E; Ferrerio Mählmann, R; Lugovic, B ‘High-grade metamorphic soles from the Central Dinaric Ophiolite Belt and their significance for the Neotethyan evolution in the Dinarides’// Ofioliti (2019), 44(1), 1-30, DOI: 10.4454/ofioliti.v44i1.462

Slovenec, Da; Segvic, B ‘Boninitic volcanism in the NW Dinaric-Vardar ophiolite zone (Mt. Medvednica, Croatia): petrology, geochemistry and tectono-magmatic evidences for existence Middle-Late Jurassic arc-forearc system in Tethyan subduction factories’// Mineralogy and Petrology (2019), 113, 17-37, DOI: 10.1007/s00710-018-0637-0

Segvic, B; Girardclos, S; Zanoni, G; Arbiol González, C; Steimer-Herbet, T; Besse, M ‘Origin and Paleoenvironmental Significance of Fe-Mn Nodules in the Holocene Perialpine Sediments of Geneva Basin, Western Switzerland’// Applied Clay Sciences (2018), 60, 22-39, DOI: 10.1016/j.clay.2018.01.027 link here

Cuadros, J; Segvic, B; Dekov, V; Michalski, J; Baussà Baradaji, D ‘Electron microscopy investigation of the genetic link between Fe oxides/oxyhydroxides and nontronite in submarine hydrothermal fields’// Marine Geology (2018), 395, 247-259, DOI: 10.1016/j.margeo.2017.10.011 link here

Leila, M; Moscariello, A; Segvic, B ‘Geochemical constraints on the provenance and depositional environment of the Messinian sediments, onshore Nile Delta, Egypt: Implications for the Late Miocene paleogeography of the Mediterranean’// Journal of African Earth Sciences (2018), 143, 215-241, DOI: 10.1016/j.jafrearsci.2018.03.024 

Mahrous, M*; Segvic, B; Zanoni, G; Khadka, SD; Senadheera, S; Jayawickrama, PW ‘The role of clay swelling and mineral neoformation in the stabilization of high plasticity soils treated with fly ash and metakaolin based geopolymers’// Minerals (2018), 8(4), 146, DOI:10.3390/min8040146 (*student author)

Benvenuti, A*; Segvic, B; Moscariello, A ‘Tunnel valley deposits from the southern North Sea ˗ material provenance and depositional processes‘// Boreas (2018), 47 (2), 625-642, DOI: 10.1111/bor.12292 (*student author) link here

Slovenec, Da; Segvic, B ‘The first record of ultramafic cumulates from the Mt. Kalnik ophiolite mélange in the SW part of the Zagorje-Mid-Transdanubian Zone (NW Croatia): mineralogy, petrology, geochemistry and tectono-magmatic affinity’// Geologia Croatica (2018), 71(3), 185-197, DOI: 10.4154/gc.2018.17

Stutenbecker, L*; Delunel, R; Schlunegger, F; Adrião Silva, T; Segvic, B; Girardclos, S; Bakker, M; Costa, A; Lane, S; Loizeau, J-L; Molnar, P; Akçar, N; Christl, M ’Reduced sediment supply in a fast eroding landscape? A multi-proxy sediment budget of the upper Rhône basin, Central Alps’// Sedimentary Geology (2018), 375, 105–119, DOI: 10.1016/j.sedgeo.2017.12.013 (*student author) link here

Ragusa, J*; Kindler, P; Segvic, B; Ospina-Ostios, L. M ‘Provenance analysis of the Voirons Flysch (Gurnigel nappe, Haute-Savoie, France): Stratigraphic and paleogeographic implications‘// International Journal of Earth Sciences (2017), 106 (8), 2619-2651, DOI: 10.1007/s00531-017-1474-9 (*student author)

Segvic, B; Benvenuti, A; Moscariello, A ‘Illite-smectite rich clay parageneses from Quaternary tunnel valley sediments of the Dutch Southern North Sea - mineral origin and paleoenvironment implications‘// Clays and Clay Minerals (2016), 64 (5), 488-507, DOI: 10.1346/CCMN.2016.064026. link here

Zanoni, G*; Segvic, B; Moscariello, A ‘Clay mineral diagenesis in Cretaceous clastic reservoirs from west African passive margins (the South Gabon Basin) and its impact on regional geology and basin evolution history’// Applied Clay Sciences (2016), 134 (3), 186-209, DOI: 10.1016/j.clay.2016.09.032 (*student author) link here

Segvic, B; Lugovic, B; Slovenec, Da; Meyer, H-P ‘Mineralogy, petrology and geochemistry of amphibolites from the Kalnik Mt. (Sava Unit, North Croatia): Implications for the evolution of north-westernmost part of the Dinaric-Vardar branch of Mesozoic Tethys’// Ofioliti (2016), 41 (1), 35-58, DOI: 10.4454/ofioliti.v41i1.441

Segvic, B; Ugarkovic, M; Süssenberger, A; Ferreiro Mählmann, R; Moscariello, A ‘Compositional properties and provenance of Hellenistic pottery from the necropolis of Issa with evidences on the cross-Adriatic and the Mediterranean-scale trade’// Mediterranean Archaeology & Archaeometry (2016), 16 (1), 23-52, DOI: 10.5281/zenodo.44773

Segvic, B; Kukoc, D; Dragicevic, I; Vranjkovic, A; Brcic, V; Gorican, S; Babajic, E; Hrvatovic, H; ‘New record of Middle Jurassic radiolarians from mélange of the Central Dinaridic Ophiolite Zone (CDOB) and its implications to Neotethyan dynamics in the Dinarides’// Ofioliti (2014), 39 (1), 31-41, DOI: 10.4454/ofioliti.v39i1.427

Segvic, B; Mileusnic, M; Aljinovic, D; Vranjkovic, A; Mandic, O; Pavelic, D; Dragicevic, I; Ferreiro Mählmann R ‘Magmatic Provenance and Diagenesis of Miocene Tuffs from the Dinaride Lake System (The Sinj Basin, Croatia)’// European Journal of Mineralogy (2014), 26 (1), 83-101, DOI: 10.1127/0935-1221/2013/0025-2350 link here

Uzarowicz, Ł; Segvic, B; Michalik, M; Bylina, P ‘The effect of hydrological conditions and the pH of environment on phyllosilicate transformations in the weathering zone of pyrite-bearing schists in Wieściszowice (SW Poland)’// Clay Minerals (2012), 47, 401–417, DOI: 10.1180/claymin.2012.047.4.01 link here

Segvic, B; Seselj, L; Slovenec, Da; Lugovic, B; Ferreiro Mählmann, R ‘Composition, Technology of Manufacture, and Circulation of Hellenistic Pottery from the Eastern Adriatic: A Case Study of Three Archaeological Sites along the Dalmatian Coast, Croatia’// Geoarchaeology (2012), 27 (1), 63-87. DOI: 10.1002/gea.21379 link here

Ferreiro Mählmann, R; Le Bayon, R; Bozkaya, Ö; Potel, S; Segvic, B; Nieto García, F ‘Clay mineral diagenesis/very low-grade metamorphic processes - The pioneer work of Bernhard Kübler and Martin Frey in very low-grade metamorphic terraines: Palaeo-geothermal potential of Kübler-Index – organic matter reflectance correlation’// Swiss Journal of Geosciences (2012), 105, 121-152. DOI: 10.1007/s00015-012-0115-3 link here

Uzarowicz, Ł; Skiba, S; Skiba, M; Segvic, B ‘Clay mineral formation in soils developed in a pyrite-bearing schists weathering zone: a case study from the abandoned pyrite mine in Wieściszowice (Lower Silesia, SW Poland)’// Clays and Clay Minerals (2011), 59 (6), 581-594. DOI: 10.1346/CCMN.2011.0590604 link here

Kandler, K; Schütz, L; Jäckel, S; Lieke, K; Emmel, C; Müller-Ebert, D; Ebert, M; Scheuvens, D; Schladitz, A; Segvic, B; Wiedensohler, A; Weinbruch, S ‘Ground-based off-line aerosol measurements at Praia, Cape Verde, during the Saharan Mineral Dust Experiment: Microphysical properties and mineralogy‘// Tellus B (2011), 63 (4), 459–474. DOI: 10.1111/j.1600-0889.2011.00546.x

Lugovic, B; Segvic, B; Segvic, T ‘Mn-crust todorokite mineralization on SW backshore Cretaceous limestones from the island of Dugi Otok (Central Adriatic, Croatia)’// Acta Adriatica (2008), 49, 55-64.

Segvic, B; Lugovic, B; Tadej, N; Bermanec, V; Panjkota, L ‘Si-P impure Al-goethite mineralization on the island of Dugi Otok (Central Adriatic, Croatia)’// Geologia Croatica (2008), 61, 139-147. DOI: 10.4154/GC.2008.04

Lugovic, B; Segvic, B; Altherr, R ‘Petrology and tectonic significance of greenschists from the Medvednica Mts (Sava Unit, NW Croatia)’// Ofioliti (2006), 31, 39-50. DOI: 10.4454/ofioliti.v31i1.326

Papers in Review

Shawwa, N; Chesnel, V; Segvic, B; Makhloufi, Y; Merino-Tomé, Ó; Fernández, L.P; Samankassou, E ‘Linking subaerial exposures to lower Pennsylvanian climatic changes: Insights from the Valdorria carbonate platform, northern Spain’// Sedimentology

Monson, CM; Tarokh, A; Kim, K; Makhnenko, RY; Sweet, DE; Segvic, B; Cheng, G; Zanoni, G; Horita, J ‘Characterization of the Carbon Storage Sink-and-Seal System Within the Glasford Meteorite Impact Structure (Illinois, USA)’// Geochemistry, Geophysics, Geosystems

Leila, M; Moscariello, A; Segvic, B ‘Differentiation of pre- and syn-Messinian salinity crisis sandstone in the Nile Delta onshore region based on their diagenetic signatures’ // Marine and Petroleum Geology 



JULY 2019

Luka performs as a real geologist questing after truth in Neogene tuffs. Field work in the Sarajevo Basin, Bosnia and Herzegovina.

MAY 2019

Hunter gives a poster presentation at the AAPG Annual Convention and Exhibition in San Antonio, TX.

MAY 2019

Colton gives a poster presentation at the 2019 TTU Geosciences Research Day


Small step for mankind but a big leap for us - our Bruker D8 Advance is being delivered. 


Giving a plenary lecture at the Mid-European Clay Conference in Zagreb. 


With old friends, Ömer and Rafael at the Mid-European Clay Conference in Zagreb. 

JULY 2017

Clay mafia, summer edition - International Clay Conference in Granada.

JULY 2017

This is why we all love Spain :) - International Clay Conference in Granada.

MAY 2017

Moustapha's first conference talk! Bravo mec! At the Texas Academy of Science Annual Meeting in Midland.

MAY 2017

Giovanni at the Texas Academy of Science Annual Meeting in Midland.





Department of Geosciences, Texas Tech University
1200 Memorial Circle
Lubbock, TX 79409, U.S.A.