Mineralogy/Igneous Petrology/Exoplanets/California Wildfires & Forest Management/Teaching
My research interests are in Igneous Petrology (how volcanoes work; mantle processes), rocky Exoplanets (nominal Earth- or inner planet-like objects that orbit nearby stars) and Forest Management and CA Wildfires (how management practices might impact the spread of wildfires in CA)
Left: (or above if viewing on a cell phone) My wife, Heather, and I at Mt. Rushmore.
At Fresno State (California State University, Fresno) I teach undergraduate courses on Mineralogy, Igneous and Metamorphic Petrology, Analytical Methods in the Earth Sciences (XRF, XRD, Optics), and for non-majors, Natural Science. At the graduate (M.S.) level, I teach Volcanology, Thermodynamics, Modeling (Excel, Regression modeling, AI), and CA Wildfires and Forest Management.
Exoplanets
Convert Star Comps. to Element & Oxide Wt. %, Mineral Proportions
Input: Stellar compositions as ratios (e.g., Fe/H, Si/H, etc.) in dex notation (log units, relative to Sun.
Output: Star composition as element and oxide weight %; mineral proportions; classificaiton diagrams (from Putirka and Xu 2021).
Our New paper on Exoplanet Rock Types From Polluted White Dwarfs can be found here: https://www.nature.com/articles/s41467-021-26403-8,; it was highlighted in 2021 here: https://www.nature.com/collections/hbeagebfch, and additional error analysis (plots of Monte Carlo simulations) can be found here: https://drive.google.com/file/d/1yQpM4W0bGLGSh6gbou4ONYg128CuVtKa/view?usp=sharing
Mineralogy/Petrology
Below are links to Excel sheets. The Excel workbooks will open as Google Sheets, and these seem to faithfully maintain all calculations. However, to view any of the classification diagrams or plots, download the files from Google Sheets as Excel-formatted workbooks. Also, note that you may have to set Excel Preferences to allow for Iterative Calculations (go to Excel > Preferences > Calculations > click the box that says "use iterative calculation"). There are no macros in any of these sheets, but many iterative calculations (Excel's numerical solving tool). Finally, to add new data, either overwrite the existing rows, or add new data below the last row, then fill down the calculation cells. Here is a YouTube site where I post tutorials: https://www.youtube.com/playlist?list=PLnOXMT9X-AL_No_vUkkx8tYrahGQ1X4Kh
Here is a YouTube tutorial on how we test for equilibrium and reconstruct equilibrium liquids:
https://www.youtube.com/watch?v=CjKvgXrah_k&list=PLnOXMT9X-AL_No_vUkkx8tYrahGQ1X4Kh&index=2
Excel Spreadsheets for Mineralogy/Igneous Petrology
See also Penny Wieser's Python programs which solve most of these equations:
https://thermobar.readthedocs.io/en/latest/index.html, and her general website, here: https://sites.google.com/view/penny-wieser
Amphibole Thermobarometry
Input: Amphibole and liquid compositions
Output: Tests of equilibrium; P-T conditions of amphibole crystallization; classification diagrams (Leake et al. 1997, Mg# v Si; ternary plots of Putirka (2016).
Clinopyroxene Thermobarometry
Input: Clinopyroxene and liquid compositions
Output: Tests of equilibrium (Rhodes diagram; pred. vs. meas cpx compositions); P-T conditions of cpx crystallization;classification diagram (Wo-En-Fs ternary).
Mantle Potential Temperature
Input: Oxygen fugacity; A liquid composition thought to be in equilibrium with mantle olivine
Output: Tests of equilibrium (Rhodes diagram); Composition of equilibrium olivine; Ol-liq equilibration T & P; melt fraction; mantle potential T.
Olivine-Liquid Thermometry
Input: Olivine and liquid composition; water in liquid, pressure of equilibration
Output: Tests of equilibrium (Rhodes diagram); T of olivine crystallization
Feldspar-Liquid Thermometry
Input: Plagioclase or Alkali Feldspar and a liquid composition; water in liquid, pressure of equilibration
Output: Tests of equilibrium; T of feldspar (plagioclase or alkali feldspar) crystallization
Orthopyroxene Thermobarometry
Input: Orthopyroxene and liquid composition
Output: Tests of equilibrium (Rhodes diagram); Orthopyroxene crystallization P-T conditions; classification diagram (Wo-En-Fs ternary).
Two-Feldspar Thermometry
Input: Coexsisting alkali and plagioclase feldspar compositions; pressure of equilibration
Output: Tests of equilibrium; T of equilibration; classification diagram for feldspar types (Or-Ab-An ternary).
Two-Pyroxene Thermobarometry
Input: Coexisting pyroxene compositions
Output: Tests of equilibrium; P-T conditions of equilibration; classification diagram for both pyroxene types (Wo-En-Fs ternary).
Tutorials on the Excel Sheets on YouTube Can be Found Here:
https://www.youtube.com/playlist?list=PLnOXMT9X-AL_No_vUkkx8tYrahGQ1X4Kh
And at these links there are...
Lectures on Mineralogy:
https://www.youtube.com/channel/UCmPqz2hUZrU-oIdpGoc6h3Q
Lectures on Igneous and Metamorphic Petrology:
https://www.youtube.com/channel/UCegi9KSdtaOMfsZ1iKMM25A
and additional content (Excel tutorials, and some research presentations):