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APT Technique Development and Applications
The study of chemical mineralogy has been a major source of information within Earth Sciences for more than a century, as minerals actively record geological processes during and after their formation. Atom-probe tomography (APT) – the highest spatial resolution analytical technique in existence for the characterization of materials – has been recently added to the currently available techniques for mineral analysis. APT can provide additional geochemical information at the atomic scale for nanoscale volumes of material. This technique is uniquely capable of providing structural insight at the atomic scale by directly mapping the location and chemical identity of the atoms within a small sample of material. Despite a rising interest in APT in Geosciences, very few geologists know how to use APT to access geochemical information of minerals. Our aim is to develop the APT technique and its application for a better understanding of wide range of geological processes.
At the UA GeoAPT laboratory we seek to develop the APT technique for improving the geochemical characterization of minerals, within a multidisciplinary research framework. Our work utilizes resources owned and maintained by the Alabama Analytical Research Center (AARC), which is supported by The University of Alabama.
APT research is analytically intensive, as we attempt to standardize methods to fabricate appropriately shaped, nanometer scale, tips of geological materials using a focused ion beam (FIB) for subsequent APT compositional analysis. The fabrication of tips from such brittle materials is not a straightforward process and currently presents a major challenge to successful APT analysis.
Optimal analysis protocols and post-processing techniques are also being developed to determine if the relative abundances of major, minor and trace elements and isotopes of minerals can be successfully quantified and imaged at the atomic scale.
The advancements in technique development will encourage new approaches to geochemistry research and provide a better understanding of the mineralization and diagenetic processes at the atomic scale.
At the UA GeoAPT laboratory we seek to develop the APT technique for improving the geochemical characterization of minerals, within a multidisciplinary research framework. Our work utilizes resources owned and maintained by the Alabama Analytical Research Center (AARC), which is supported by The University of Alabama.
APT research is analytically intensive, as we attempt to standardize methods to fabricate appropriately shaped, nanometer scale, tips of geological materials using a focused ion beam (FIB) for subsequent APT compositional analysis. The fabrication of tips from such brittle materials is not a straightforward process and currently presents a major challenge to successful APT analysis.
Optimal analysis protocols and post-processing techniques are also being developed to determine if the relative abundances of major, minor and trace elements and isotopes of minerals can be successfully quantified and imaged at the atomic scale.
The advancements in technique development will encourage new approaches to geochemistry research and provide a better understanding of the mineralization and diagenetic processes at the atomic scale.
Research Collaborators
- Kim Genareau (UA): Characterization of volcanic samples.
- Julia Cartwright (UA): Characterization of meteorites.
- Harold Stowell (UA); Analysis of garnets
- Rinat Gabitov (Mississippi State University): Characterization of carbonates.
- Tanya Prozorov (Ames Laboratory): Analysis of micas and clay minerals.
- Elena Miranda (Cal State Northridge University): Characterization of silicates associated to fault zones.
- Stephen Parman (Brown University): Characterization of grain boundaries.
- John Valley (University of Wisconsin-Madison): Analysis of water in minerals.
- Kim Genareau (UA): Characterization of volcanic samples.
- Julia Cartwright (UA): Characterization of meteorites.
- Harold Stowell (UA); Analysis of garnets
- Rinat Gabitov (Mississippi State University): Characterization of carbonates.
- Tanya Prozorov (Ames Laboratory): Analysis of micas and clay minerals.
- Elena Miranda (Cal State Northridge University): Characterization of silicates associated to fault zones.
- Stephen Parman (Brown University): Characterization of grain boundaries.
- John Valley (University of Wisconsin-Madison): Analysis of water in minerals.
APT and Biomineralization
Organisms exert a precise control over biomineral formation from the molecular to the macroscopic levels. Our current work tries to decipher how organisms control mineral composition (i.e., polymorph selection), morphology, crystallography, and structure. Also, we aim to understand geochemistry in the context of biomineralization. We are using APT for the nanoscale geochemical characterization of organics associated to biominerals.
Research Collaborators
- Michio Suzuki (University of Tokyo): Characterization of intra-crystalline organics.
- Tanya Prozorov (Ames Laboratory) and Concepcion Jimenez (Universidad de Granada): Characterization of biogenic magnetite.
- Michio Suzuki (University of Tokyo): Characterization of intra-crystalline organics.
- Tanya Prozorov (Ames Laboratory) and Concepcion Jimenez (Universidad de Granada): Characterization of biogenic magnetite.
Current Research Projects
"Intra-clay trapping of organic molecules – A key step in the chemical evolution of life?”. National Science Foundation (NSF) – EAR – Geobiology & Low-Temperature Geochemistry (NSF Proposal # EAR-2019870)
“Collaborative Research: The Antarctic Scallop as a Key to Paleoenvironment and Sea Ice Conditions: Understanding the Modern to Predict the Past”. National Science Foundation (NSF) – EAR – Antarctic Earth Sciences (NSF Proposal #EAR-1745064).
“Atom Probe Tomography (APT) development and optimization for applications in Earth Sciences”. National Science Foundation (NSF) – EAR – Instrumentation & Facilities (NSF Proposal # EAR-1647012)
“Collaborative Research: The Antarctic Scallop as a Key to Paleoenvironment and Sea Ice Conditions: Understanding the Modern to Predict the Past”. National Science Foundation (NSF) – EAR – Antarctic Earth Sciences (NSF Proposal #EAR-1745064).
“Atom Probe Tomography (APT) development and optimization for applications in Earth Sciences”. National Science Foundation (NSF) – EAR – Instrumentation & Facilities (NSF Proposal # EAR-1647012)