Planetary Science Research

Early Solar System Research Group (Professors Adrian Brearley and Rhian Jones)

Our research group focuses on the earliest history of the solar system, through the study of chondritic meteorites. These meteorites are fragments of asteroids that have remained unmelted since they formed over 4.56 billion years ago. Through the study of chondritic meteorites, we are learning about the earliest geologic evolution of the solar system, from the formation of the earliest solids in the protoplanetary disk around the Sun, the processing of this material in the disk, and it's subsequent accretion into asteroidal parent bodies. We are also actively involved in understanding processes that occurred on asteroids that may have modified chondritic meteorites after they accreted. These processes include aqueous alteration and thermal metamorphism.

We use a variety of analytical techniques to study the mineralogy, petrology, and chemical composition of chondritic meteorites and their constituents. Many of these techniques are available in the Department of Earth and Planetary Sciences and Institute of Meteoritics. We have a range of superbly equipped laboratories that include include a scanning electron microscope, electron microprobe, transmission electron microscope, secondary ion mass spectrometer and stable isotope mass spectrometers. For additional analytical techniques we collaborate with colleagues at other institutions as required.

ADRIAN BREARLEY - ACTIVE RESEARCH AREAS

The following research areas are areas in which I currently have active research projects funded by various NASA grants from the NASA Cosmochemistry, Origins of Solar Systems, Exobiology and Stardust programs.

    Click on the small image at the end of each bullet for more information.

    Origin of fine-grained matrix materials in chondritic meteorites

    Aqueous alteration of carbonaceous chondrites 

    Origin of carbonaceous materials in chondritic meteorites

    Thermal histories of chondritic meteorites and their components.

    Effects of thermal metamorphism on ordinary and carbonaceous chondrites

    Alteration and thermal histories of CAIs in carbonaceous chondrites

    Analysis and origins of STARDUST cometary particles

Martian meteorites

    Origin of nanophase magnetites in martian orthopyroxenite, ALH84001

    Origin of high water contents in olivines in Nakhla (with Prof. Darby Dyar, Mount Holyoke College).

My terrestrial research interests are centered around understanding the mechanisms and kinetics of high pressure phase transformations in the mantle and their implications for mantle rheology, dynamics and deep focus earthquakes, as well as the mineralogy and petrology of mantle xenoliths. However, I also work on a variety of problems in metamorphic petrology, including mechanisms of metamorphic reactions under disequilibrium conditions, experimental studies of partial melting reactions involving micas in upper crustal rocks and the metamorphic petrology of contact and low grade metamorphic rocks.

Current planetary science and early solar system research projects:

Planetary science and early solar system research

Formation and alteration histories of chondritic meteorites (NASA Cosmochemistry Program).

This project is a multifaceted project that consists of many subproject. Some of these are listed below.

• Studies of aqueous alteration processes in primitive carbonaceous chondrites (NASA)
• Mineralogy and chemistry of fine-grained matrices and rims in chondritic meteorites (NASA).
• Nature and origin of fine-grained matrix materials in primitive chondrites (NASA).
• Effects of metamorphism on the chemistry and microstructural characteristics of carbonaceous chondrite matrices (NASA).
• Origin of carbonates in CM carbonaceous chondrites (NASA). Images of altered CM chondrites
• Origin of carbonates and associated minerals in Martian orthopyroxenite ALH 84001 (NASA).
• Origin of dark inclusions in CV carbonaceous chondrites (NASA).
• Thermal histories of chondrules and chondrites based on the microstructures of pyroxenes (NASA).
• High resolution TEM image of disordered biopyriboles replacing enstatite in a chondrule from the Allende meteorite

Mechanisms and kinetics of aqueous alteration reactions in chondritic meteorites (NASA Origins of Solar Systems Program)

• The reaction of liquid or gaseous water with the components of chondritic meteorites was an important and widespread process in the early solar system. It clearly contributed considerably to the evolution of important primitive solar system materials such as carbonaceous chondrites and interplanetary dust particles. With graduate student Paul Burger and Postdoctoral Researcher Barbara Cohen, we are studying carrying out experimental investigations of the kinetics and mechanisms of alteration reactions that affected a variety of chondritic materials. This research aims to place constraints on the possible timing, locations, conditions and nature of these aqueous alteration processes, using experimental methods.

Nature, origins and thermal processing of carbonaceous material in chondritic meteorites: In situ location using energy filtered transmission electron microscopy (NASA Exobiology Program).

Terrestrial research projects