O'Farrell, Keely A

Dr. Keely O'Farrell's Research Group
A:
1 Research Overview
My research group focuses on the uid dynamics of Earth and planetary mantles and their surface manifestations. By necessity, convection in planetary mantles is largely studied using numerical models on supercomputers, though the right parameter range is still often out of reach. My previous work has lead to the development of scaling equations to adjust the mean temperature of plane-layer models to emulate the hotter temperatures found in full spherical shell convection whilst saving dramatically on computational cost (O'Farrell and Lowman, 2010; O'Farrell et al., 2013). My work has expanded to include the surface manifestations of convection using proxies for the density structure of the Earth (i.e. seismic tomography) to predict Earth's gravitational potential and plate motions and its dependence on mantle viscosity structure. This work is being used to constrain the viscosity structure of the Earth for future convection models. Recently, we have been exploring the plume structure inside the Earth to see if we can track the source of plumes and their surface manifestations. Using 3D seismic tomography data we developed an algorithm to trace the minimum seismic velocity values (associated with hotter mantle) up through the mantle. Future work on this will require renement of our algorithm to analyze higher resolution models. Long-term research goals include developing an understanding of dierent aspects of mantle convection including: (1) the internal structure of the Earth (2) the role of plumes and their surface expression at hotspots, (3) the dynamics of a hotter early Earth and (4) the processes controlling plate tectonics here and on other planets.

B:
2 Projects
2.1 Project: Earth viscosity structure
Using seismic tomography as a proxy for density, we predict the Earth's gravitational potential and 

Personnel: Keely O'Farrell (UK), Carolina Lithgow-Bertelloni (UCL)

Computational Methods: A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require
as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth. The geoid inversion code has been developed in fortran and runs on a single processor easily (but hundreds of models are run for the study).

Software: The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT.  The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

2.2 Project: Plumes and their surface manifestation
Personnel: Keely O'Farrell (UK), Caroline Eakin (ANU), Carolina Lithgow-Bertelloni (UCL), Matt Jackson (UCSB), Vedran Lekic (U Maryland), Max Rudolph (Portland)

Computational Methods: A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require
as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software: The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT.  The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead of installing on DLX).

2.3 Project: Characteristics of mantle convection models

Personnel: Keely O'Farrell (UK),
Computational Methods: A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require
as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software: The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab, GMT and gnuplot.  The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

2.4 Project: Early Earth exploration

Personnel: Keely O'Farrell (UK), David Willis, PostDoc

Computational Methods: A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require
as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software: The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT.  The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

2.5 Project: Dinosaur impact event
Dinosaurs were wiped out of existence 65 million years ago after a large impact event on Earth. Around the same time there was an increased amount of volcanic activity in an area known as the Deccan Traps in India. There is evidence to support that these two events are related. In this project we will explore the eect of a large impact crater on one side of the Earth by modelling this numerically with a mantle convection model. We will use plate reconstruction histories from the last 100-200 Ma to observe how this impact might have changed the ow of mantle at the other side of the Earth.

Personnel: Keely O'Farrell (UK),

Computational Methods: A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require
as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software: The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT.  The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

Dr. Keely O'Farrell's Research Group
Research Overview - My research group focuses on the uid dynamics of Earth and planetary mantles and their surface manifestations. By necessity, convection in planetary mantles is largely studied using numerical models on supercomputers,
though the right parameter range is still often out of reach. My previous work has lead to the development of scaling equations to adjust the mean temperature of plane-layer models to emulate the hotter temperatures found in full spherical shell convection whilst saving dramatically on computational cost (O'Farrell and Lowman, 2010; O'Farrell et al., 2013). My work has expanded to include the surface manifestations of convection using proxies for the density structure of the Earth (i.e. seismic tomography) to predict Earth's gravitational potential and plate motions and its dependence on mantle viscosity structure. This work is being used to constrain the viscosity structure of the Earth for future convection models. Recently, we have been exploring the plume structure inside the Earth to see if we can track the source of plumes and their surface manifestations. Using 3D seismic tomography data we developed an algorithm to trace the minimum seismic velocity values (associated with hotter mantle) up through the mantle. Future work on this will require renement of our algorithm to analyze higher resolution models. Long-term research goals include developing an understanding of dierent aspects of mantle convection including:
(1) the internal structure of the Earth
(2) the role of plumes and their surface expression at hotspots,
(3) the dynamics of a hotter early Earth and
(4) the processes controlling plate tectonics here and on other planets.

Earth viscosity structure

Using seismic tomography as a proxy for density, we predict the Earth's gravitational potential and

Personnel:

Keely O'Farrell (UK)
Carolina Lithgow-Bertelloni (UCL)
Sean Trim, PostDoc, (University of Saskatchewan)

Computational Methods:

A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth. The geoid inversion code has been developed in fortran and runs on a single processor easily (but hundreds of
models are run for the study).

Software:

The software we use for running models are fortran and c compilers (Intel or g fortran, as well as LAPACK. We run analysis using Matlab and GMT. The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

Plumes and their surface manifestation

Personnel:

Keely O'Farrell (UK), Caroline Eakin (ANU), Carolina Lithgow-Bertelloni (UCL), Matt Jackson (UCSB), Vedran Lekic (U Maryland), Max Rudolph (Portland)

Computational Methods:

A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nite dierence-spectral methods. Models can use as little as 1 processor or require as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software:

The software we use for running models are fortran and C compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT. The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead of installing on DLX).
Characteristics of mantle convection models

Personnel: Keely O'Farrell (UK)

Computational Methods:

A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nitedierence-spectral methods. Models can use as little as 1 processor or require as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software:

The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab, GMT and gnuplot. The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

Early Earth exploration

Personnel: Keely O'Farrell (UK), future postdoc

Computational Methods:

A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nitedierence-spectral methods. Models can use as little as 1 processor or require as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software:

The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT. The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).

Dinosaur impact event

Dinosaurs were wiped out of existence 65 million years ago after a large impact event on Earth. Around the same time there was an increased amount of volcanic activity in an area known as the Deccan Traps in India. There is evidence to support that these two events are related. In this project we will explore the eect of a large impact crater on one side of the Earth by modelling this numerically with a mantle convection model. We will use plate reconstruction histories from the last 100-200 Ma to observe how this impact might have changed the low of mantle at the other side of the Earth.

Personnel:

Keely O'Farrell (UK)

Computational Methods:

A number of dierent cartesian and spherical shell convection models can be used for our studies. Currently the models we are using are written in Fortran and C using nite element and nitedierence-spectral methods. Models can use as little as 1 processor or require as many as 128 high memory processors to run full Earth-like models for the evolution time-scale of the Earth.

Software:

The software we use for running models are fortran and c compilers (Intel or g fortran), as well as LAPACK. We run analysis using Matlab and GMT. The compilers are available on DLX and GMT is free to download (but can be used on a local computer instead).