John D. Greenough
Contact Info:
Dr. John D. Greenough
Department of Earth and Environmental Sciences
Location: SCI 216,
Telephone: (250) 807 9520
FAX: (250) 807 8005
E-mail: john.greenough@ubc.ca
I specialize in using the trace element composition of mafic rocks to study the early history of the Earth and the processes that cause differentiation in recent basalt lava flows. My geochemical ’Äútoolbox’Äù has also opened the door to projects in geoarchaeology (’Äúfingerprinting’Äù and sourcing artifacts) and wine trace element geochemistry. At the heart of many recent projects is an initial analysis of the data using an exploratory statistical technique called multidimensional scaling. This technique is completely new to geochemistry but provides a powerful tool for finding patterns in giant (many elements & samples) data sets. The list of in-progress projects below, my publications, and the list of possible student research projects give insight into my fields of expertise.
In-Progress Research Projects
The
World-wide Signature of the Mantle Components. Now that my paper on the composition of the mantle components using
French Polynesia basalts is in press, I am moving ahead with a supercharged and
expanded version of this project using a larger (more islands) but degraded
(more ’Äúholes’Äù) data matrix. The objective is to use trace element ratios to
finger-print the mantle components and finally figure out how they formed.
Core-mantle Interaction? Preliminary
results indicate that regression analysis applied to multiple samples of basalt
from individual oceanic islands can yield accurate relative estimates of mantle
siderophile element concentrations. The work to-date shows there are major
differences between oceanic islands. The question is, are these due to
core-mantle interaction with material being brought up in ’Äúmantle plumes’Äù or do
the siderophile element variations reflect recycled lithospheric rocks?
Integration with results on mantle component compositions will provide answers.
Diamond Indicator Minerals. My
graduate student at the U. Windsor (with Brian Fryer, and supported by
Composition of the Lunar Regolith.
Dr. David McKay (Houston Space Centre; Life on Mars?) and I have been
discussing a project that would determine trace element variability in Lunar
regolith as a means of investigating compositional variation of the Lunar
surface. The project will begin with an analysis of existing electron
microprobe data on Apollo-mission samples and then use LA-ICP-MS to determine
trace element compositions.
Lunar and Martian Mantle Composition.
The statistical techniques (multidimensional scaling) that identified four
mantle component compositions in
Dating Mantle Below
Dating a Ni-Cu-Co-Pt-bearing Layered Mafic Intrusion in
Volatile Influenced Differentiation in Lava Flows. We analyzed minerals from a
Analysis of Trace Elements in Gold. The
geoarchaeology project below requires new analytical techniques to determine
the trace element composition of gold. I have been working with Dr. Fryer (U.
Windsor) on this project. There are other potential uses of these analytical
techniques as shown by my honors student, Mr. McInnes, who used whole-sample
gold analyses to determine the source of some placer gold.
Fingerprinting and Tracing Gold.
The project will determine the trace element content of 1000 BC gold artifacts
from the Near and Middle East and try to determine where gold was mined and how
it was traded. The gold was removed from priceless artifacts at museums around
the world. Fryer is running the samples using a new analytical technique. This
project is with Mallory-Greenough and Fryer.
Trace Element Composition of Maple Syrup. Projects on the trace element composition of wine, that date back to the mid-nineties, have provided insight into how plants take up elements and how climate, soils and human inputs affect what we eat and drink. The project will see whether, like vineyards, individual maple sugar stands can be fingerprinted. We are also interested in the effect of reverse osmosis versus evaporation-only on the trace element and oxygen isotopic composition of syrup. We have samples for the last 6 years and they have been run in Dr. Fryer’Äôs lab.
Along with my research projects a number of personal and professional interests occupy my time:
One of the most successful things I have been involved with is
the layman's book Okanagan Geology, a
project initiated and led by
With my research partner ’Äì Catherine Greenough. |
Because photographic skills are important in the Natural Sciences and because photography is one of my favorite hobbies, the annual Science Photography Contest was established in the early 1990's. Run with the help of the Earth and Environmental Sciences clubs rules change from year to year but usually involve categories such as Flora, Fauna, Landscapes and Photo-microscopy/photo-telescopy with voting during a get-together/party. For further information about the upcoming contest contact yours truly.
Considering my professional enthusiasm for petrology and mineralogy and that I teach Mineralogy at UBC O, it is not surprising that one of my interests is Gemology. I am particularly enthralled with colored varieties of diamond, corundum (ruby and sapphire), beryl (aquamarine and emerald), tourmaline (indicolite and rubellite) and topaz as well as the upper mantle minerals olivine (peridot) and diopside. Stones in my collection are usually shown to the Mineralogy and Introductory Earth and Environmental Sciences students.
Each year I deliver several talks to service clubs and usually visit two or more elementary, middle- or high-schools to talk about the Earth sciences. Hobbies include playing the guitar (Larrivˆ©e, Hohner, Gibson S1, Fender Strat), hiking and fishing, and cooking/eating east-coast shell fish! I also like sports cars and own a black 1988 Fiero GT in excellent condition.
Possible
Research Projects/Student Research
1. Composition of Mantle Components in the Ocean Basins (GEOROC database studies).
2. Composition of the Archean Subcontinental Lithosphere
(Isotopes;
3. Model Ages for the Mantle Components (MORB and GEOROC database studies).
4. Siderophile Element Composition of the Mantle (Core-Mantle Interaction)?
5. Origin of Layering in Thick Basalt Flows (
6. Age Significance of a Layered Mafic Intrusion in
7. A Mineral Fingerprint search for the Pt-deposit in a Yemen Mafic Intrusion.
8. Melting Processes, and Thermal and Chemical Evolution of Lunar and Martian Mantle Reservoirs (several possible projects).
9. Fingerprinting and tracing Dacite Artefacts in the B.C. Interior (Geoarchaeology).
10. Effect of Evapo-transpiration on the Trace Element Composition of Okanagan Wines.
11. Geoarchaeology and Economic Geology Projects (there are several possible projects) using Trace Elements that Fingerprint Gold.
12. The Trace Element composition of Artefacts and Agrofood products (dozens of possible projects using statistical techniques to explore a new geochemical data base).