Ä¢¹½AV

Description: The carbonate islands of Bermuda sit on a volcanic rise of uncertain origin.  Although the basaltic flows appear to have originated at the mid-ocean ridge over 100Ma, there are younger intrusions of ultramafic lamprophyre with an unclear source.  Two lines of research are proposed for the upcoming year.

Description: There is a lack of understanding about the timing of phlogopite crystallization in ultramafic lamprophyres in general, and in the Bermuda Rise, specifically. Petrography and chemistry of the phlogopite will be used to determine whether these are primary or secondary in nature and what the chemistry of the fluids in the rocks. Study may include petrographic work, electron microprobe, and laser ICP-MS.

Description: It has been proposed by some that the carbonate veining in the volcanic rocks is magmatic in origin, related to the silica-undersaturated intrusive rocks.  Other propose that it they are recycled marine carbonates.  Paragenesis of the veins will be determined using detailed petrologic and geochemical study.  Research may include microscopy, electron microprobe, cathodoluminescence, laser ICP-MS, and carbonate isotopes.

Short description: The aim of this research project is to prepare and analyse between 5 to 10 rock samples collected along a transect crossing the inner forearc of the Hikurangi margin in the Southeastern part of the North Island of New Zealand. There, the Pacific Plate is subducted underneath the Australian plate since the late Cenozoic and the convergence has generated extensive continental deformation triggering unspecified amount of crustal unroofing. This project includes extensive laboratory work and is suitable for students interested in Geochronology and Tectonics.

Description: The lunar crust is dominated by anorthosite, which forms much of the lunar highlands, the bright and heavily cratered areas that you can see on the moon with the naked eye. This is at least 4.35 billion years old (Barboni et al. 2017) and is thought to have formed over a ~200 million year period. The anorthosites are thicker on the farside (~30-50 km) versus the nearside of the moon where they reach zero thickness in the Mare impact basins, the dark areas visible on the moon’s surface. The anorthosites are thought to have formed from a planetary-scale, magmatic fractionation process as suggested by the original lunar magmatic ocean (LMO) model (Smith et al. 1970; Wood et al. 1970). The LMO model suggests an early, 1000km deep, molten lunar surface developed and was enriched in plagioclase. Being less dense, the plagioclase floated to form the anorthosites of the lunar highlands. There are now several models supported by increasing volumes of data that suggest more complex formation mechanisms. The onion-skin model suggests a LMO with limited circulation under an initially thin, quenched crust. This produced rapid accumulation of anorthosites and minor, interstitial, mafic liquids. Tidal overturning of the plagioclase cumulates then prolonged the crystallization times (Elkins-Tanton et al. 2011). A second model, which attempts to also explain the asymmetric nature of the lunar crustal thicknesses, suggests that circulation may be the result of a giant impact which caused early differentiation of the nearside and farside lunar surfaces (Aria et al. 2008). A third model suggests that serial magmatism, and recycling of crystallizing plagioclase into a pre-existing quenched crust, produced the variety of assemblages found in many lunar samples (Gross et al. 2014). Another recent model suggests that modification of the initial crust formed from the LMO was aided by widespread early bombardment. This in turn created a series of magma seas that differentiated to result in the observed compositional variations in the lunar highlands (Vaughan et al. 2013). In this study, we will examine a small suite of lunar meteorite samples which has recently been obtained, including several pieces of NWA 11474 and NWA 12593. These meteorites are lunar breccias and contain clasts of anorthosite and mafic minerals. The first part of the project will involve a detailed documentation of the variations in mineral compositions in these samples. This will allow the range in lunar anorthosites represented to be determined. Preliminary crystallization temperatures will also be calculated using this data. Minor elements such as Sr, Ba and rare-earth elements including Eu will also be measured. Published distribution coefficients for trace-elements in plagioclase crystallizing from a LMO (Sun et al. 2017) will be used to determine whether these samples crystallized from a single-composition magma or represent more than one phase of crystallization from several magmas. Results will be compared with other studies to help refine the models of lunar crustal formation. Students interested in this project should contact Dr. Richard Cox (richard.cox@dal.ca).

Description: Granitic rocks are ubiquitous to most tectonic settings and form a wide range of magmatic units from small-scale melts (leucosomes) in migmatites, to dykes and sills, to intrusive complexes at various scales from small plutons to very large batholiths. One of the most challenging aspects in studying granitic rocks is determining the pressure and temperature ranges recorded during emplacement. This is particularly true for larger granitic complexes where contact metamorphic zones tend to record the final stages of cooling and final depth of emplacement. In this project we will examine mineral assemblages from a number of granitic plutons including the Halifax pluton, which forms part of the South Mountain Batholith, the La Baie granite from near Chicoutimi, Quebec, and the Strontian granite from the south-west Highlands of Scotland. These examples are all related to orogenic activity but were emplacement at different stages of metamorphism within these orogenic belts. In addition, these samples contain different mineral assemblages and textures which offer different possibilities in terms of analysis of mineral thermobarometers to determine the range of pressure and temperature conditions. Among the possibilities are two-feldspar thermometry, Al-in-hornblende barometry, plagioclase-hornblende thermometry, apatite-biotite thermometry, the use of multi-equilibrium assemblages, and a range of accessory mineral thermometers / barometers such as Ce- and Ti-in zircon and Zr-in-titanite and rutile. The goal of this project will be to produce complete PT-paths for at least one these intrusions. The research will involve detailed petrography and analysis using the electron microprobe at Ä¢¹½AV. A number of samples have already been studied, and this data will also be available to help with the final interpretation. Students interested in this project should contact Dr. Richard Cox (richard.cox@dal.ca).         

Nova Scotia Museum, Geology Collections
The topics and collections below may be of interest for undergraduate honours research projects. The curator can co-supervise research and facilitate access to relevant museum collections for new research.  Contact the Curator to discuss interest and potential projects.  tim.fedak@novascotia.ca 

Sand/Soil and Mineralogy 

• Specimens for comparative studies to support studies of micro-plastics in modern environment. Historic samples back to 1870s. 
• Agate: Microstructural studies of systematic collections.

Invertebrate Palaeontology

• Silurian collection from Arisaig, also McGill: Studies of morphological variation and taphonomy. brachiopods, cephalopods, starfish. 
• Carboniferous Windsor Group, with Acadia: Stratigraphic collections include type specimens. 

Carboniferous Palaeobotany 

• Cape Breton Fossil Plants, with CBU: Carboniferous palaeobotany, Zodrow collection and historic collection from 1860s.
• New, unique preservation of fossil trees in gypsum evaporites. 

Interglacial Palaeobiology - Mastodon Sinkholes of Nova Scotia

• Ongoing description and analysis of samples collected from 1990s.
• Mastodon bones, wood turtles, painted turtles, wood, moss, seeds, and unprocessed mud samples. ~80,000 years old.

Curation and 3D Digitization - Permian Trackways 

• 3D digitization of reference collection that was collected in 1994. 

Description: Kimberlites are exotic but very important volcanic rocks, which are the main primary source of diamonds and also the deepest magmas that reach the surface of the Earth. The origin of kimberlites is linked to processes in the subcontinental mantle and is still poorly understood. Due to their complex composition, we still do not know the composition, origin, and eruption conditions of kimberlites. Diamonds grow deep in the Earth’s mantle where they get picked by kimberlite magma and brought to the surface during fast kimberlite ascent. High-temperature kimberlite magmas are destructive for diamonds and diamond survival depends on the crystallization conditions and ascent rate of kimberlites. The two following experimental projects will help to address some of these questions.

Diamond dissolution in kimberlite magma during its ascent can make a large impact on diamond grade of a kimberlite pipe. Previous experimental studies examined the effect of temperature, pressure, oxygen fugacity and melt composition on diamond dissolution rate. However, the existing data has many gaps in experimental conditions which preclude development of a comprehensive model for diamond dissolution. Furthermore, the effect of solvent (melt vs. fluid) and its composition on diamond dissolution rate is very poorly constrained.

This study will conduct a series of high-pressure-temperature experiments using piston-cylinder apparatus to fill the gap in the existing experimental dataset. Especially the focus will be on exploring the effect of kimberlite composition on diamond dissolution. The results will be incorporated with a database of the existing experimental data to develop a model for calculating diamond dissolution rate using Matlab or another modelling software.

This study will provide 1) an important tool for calculating diamond preservation for various T-P-time scenario of kimberlite ascent; 2) comparison of the results of this calculation to the existing estimates of kimberlite crystallization conditions will allow to put better constraints on kimberlite ascent rate.

Hypabyssal kimberlite is the best representation of kimberlite melt composition. Hypabyssal kimberlites from worldwide localities shows seven mineral phases in the groundmass, which represent crystallization from kimberlite magma. However, experimental studies producing these mineral phases are extremely limited and do not allow to examine the role of volatiles and temperature. Towards this end, high-pressure-temperature experiments will examine liquidus phases and crystallization sequence in kimberlite melt at 1000 – 1200oC and pressure 0.5 – 1 GPa. The effect of volatiles (H2O and CO2) will be examined. Experiments will be conducted in piston-cylinder apparatus and examined using Scanning Electron Microscope and Electron Microprobe analyses. This study will shed more light on the composition of kimberlite magma.

Description: Subduction zone dynamics, including earthquake generation, are profoundly influenced by the rheological properties of the subduction interface. Current models estimating interface viscosity rely on simplified endmember flow laws or basic mixing models, yet the actual variation in interface materials can theoretically produce viscosity differences spanning up to five orders of magnitude. These variations are predominantly temperature-dependent, but even within shear zones deformed at similar temperatures, shear strength can vary by up to a factor of 50. This variability arises from differences in matrix composition, shear zone width, and block distributions within the shear zone.

To better constrain the range of strength and viscosity along deep, viscous subduction interfaces, this project will focus on a high-resolution structural and geological map of an exhumed deep subduction interface in the Swiss Alps. The study area, a recently deglaciated terrain with nearly 100% rock exposure, offers an exceptional opportunity to document the structural features of this subduction zone.

The project involves:

Geological and Structural Mapping: Utilizing high-resolution drone imagery to create a detailed map of the shear zone, capturing the geometry, structural relationships, and spatial distribution of rock types.

Rock Type and Material Database: Compiling a comprehensive database of lithologies, block-and-matrix distributions, and compositional variations within the subduction interface.

Numerical Shear Zone Simulations: Applying numerical shear experiments to quantify the bulk shear strength and viscosity of the mapped shear zone.

By integrating field observations with numerical modelling, this project aims to provide new insights into the mechanical behaviour of subduction interfaces, enhancing our understanding of subduction zone dynamics and their implications for tectonics and seismicity.

Aim of the project: Identify deformation processes that enable the continuum of stress along continental megathrusts.

Objectives: Microstructural investigation of thin sections from shear zones that have undergone a transition from crystal plastic to frictional deformation. Microstructural observations will be performed using a petrographic microscope and a scanning electron microscope. Mineral phases will be identified using the electron microprobe.

Qualifications: courses in Structural Geology and Metamorphic petrology.

Bonus: technical writing skills, meticulous work in a research lab, and high motivation for academic research.

Description: Native freshwater turtles are declining worldwide and practical methods of reducing mortality are urgently needed. In collaboration with the Chemistry Department and the NS Turtle Patrol, this project will investigate the role of the olfactory landscape and its potential for decreasing predation of turtle eggs during the sensitive 24-48 hours post nesting. This project involves a fieldwork component, and a vehicle is required. This particular project is not likely to be eligible for the GIS certificate. Students may also propose their own topics which can be discussed based on data availability and resources. All projects are pending ethics approval.

Description: Species are declining at an alarming rate across the globe and there is a need for spatial-temporal methods of analyses to contribute information to conservation management. Open data on biodiversity, protected areas, and landcover type among others are widely available to support research in this area.  Potential projects are possible and up to student interest and skill level and can include research on habitat change over time, examining wildlife-human interactions, modeling landscape connectivity, developing change models over time, and quantifying fragmentation and time to extinction. Students with skills in geospatial analysis, R coding, and/or remote sensing would be well-suited to this type of research.

Description: The Stable Isotope Biogeochemistry Lab works on a wide range of topics, from trophic ecology to the Holocene-scale climate change. We have state of the art analytical facilities located in the Steele Ocean Science Building, and an amazing and supportive team of researchers from undergraduate Honours through MSc, PhD and postdoc levels. Depending on student interest, Dr. Sherwood and the lab can support Honours projects in any of the following general areas:

1. Characterizing the composition of marine sedimentary organic matter to better inform the Blue Carbon economy. 

2. Developing new climate change proxy records from Nova Scotia lakes. 

3. Reconstructing climate change impacts on the feeding ecology of bio-archive organisms (e.g., corals, clam shells, fish scales, bird feathers, whale baleen)

Prospective students should have a genuine interest in scientific discovery, willingness to work long hours in the lab and field, and an aptitude for data analysis and writing. Please reach out to Dr. Sherwood (owen.sherwood@dal.ca) to discuss ideas and opportunities. 

Please contact Shannon to discuss potential projects in this field.

Description: Nature Check is a province-wide study that establishes the first comprehensive baseline of how Nova Scotians perceive, experience, and emotionally connect with nature. It examines the full spectrum of nature interactions from neighbourhood green spaces to coastal and wilderness experiences while identifying the social, economic, and geographic barriers that limit access, especially for marginalized or underserved communities. The Honours student will work directly with key stakeholders to co-develop the survey questions, assist with province-wide distribution, and lead the analysis of the resulting dataset. This role requires a strong background in statistical analysis and data interpretation, as well as a genuine interest in environmental education, public engagement, and community outreach. The student will play a central part in shaping both the research process and its impact across Nova Scotia. Students interested in this project should contact Dr. Tarah Wright (tarah.wright@dal.ca).

Description: The aim of this project is to investigate quarry/mining blasts near Halifax using a broadband seismic station in Halifax. Furthermore, these blasts serve as seismic sources for constructing layered velocity models of the region. This project heavily relies on computer programming and digital data analysis, requiring a significant time commitment. Students interested in this project should contact Dr. Miao Zhang (miao.zhang@dal.ca) at least three months before the class begins to ensure they can receive timely prerequisite training.