Aviv Bernstein Livne ’23, Alyssa Guzman ’22, Ana Rodriguez Gonzalez ’23, Celine Wang ’23, Christina Hennessey ’24, Lillian Jiang ’22, Megan O’Brien ’23J, Olivia Siebert ’24, Renee Gonzalez ’23, Sophia Consiglio ’22, Yulia Kuzniar ’23 and Zoe Roumeliotis ’24
Exoplanets: Finding Planets Beyond Our Star. Exoplanets orbit stars other than our sun. They can be larger than gas giants in our solar system (called “Hot Jupiters”), or smaller than Pluto. Many organizations are interested in doing research on exoplanets. Independent observatories like ours at Smith contribute data to these organizations. We specifically work with the TESS project from NASA and Pulkovo Observatory. We measure the brightness of light of a star over time, to see if it dims when an exoplanet is predicted to be transiting. This year alone we have observed 25 transits so far, and continue to observe more each week. A poster deriving from academic research with James Lowenthal, Mary Elizabeth Moses Professor of Astronomy.
Juliet Ramey-Lariviere ‘22
Controls on Bimineral Ooid Formation, Shark Bay, Western Australia. Ooid grains, a type of precipitated sand, are typically composed of calcium carbonate and are rounded in agitated water. Most ooids are composed of either aragonite or low-Mg calcite (Algeo and Waston, 1995). The minerals precipitated in ooids reflect a complex array of environmental and possibly even microbial processes, so a better understanding of the kinds of calcium carbonate minerals within ooids will help us constrain their depositional setting. The samples that I imaged in previous semesters appear to have bimineral cortices. The modern ooids from Shark Bay, Western Australia, have distinct Mg-rich rings surrounded by layers of aragonite. Sources from the literature have proposed various conditions for the precipitation of high-Mg calcite over aragonite or low-Mg calcite (Burton and Walter, 1987; Diaz and Eberli, 2019). These authors propose that the dominant controls are temperature and water saturation state. Studying these conditions will contribute to the understanding of ooid formation and its relationship with ocean chemistry. A poster deriving from Special studies with Sara Pruss, Professor of Geosciences.
Clara Brill-Carlat ‘21
Comparing Directions of Seismic Slip and Tectonic Plate Motion. Over 56,000 moderate to large earthquakes have occurred around the world since 1976, and a global earthquake catalog contains data on the fault geometry and kinematics of each of those earthquakes. A Global Block Model, constrained by GPS measurements, divides the Earth into fault blocks with kinematic data showing the movements of the blocks. Because earthquakes relieve the elastic strain that accumulates at fault boundaries, earthquake slip directions typically correspond to the direction of crustal movement at a particular fault. The goal of this project is to compare the global earthquake data to the block model in order to determine what percentage of earthquakes match the direction of fault slip predicted by the model. These comparisons can be made efficiently in MATLAB by matching the fault on which each earthquake occurred to nearby fault segments with the same geometry and kinematics. Although it is expected that the vast majority of earthquake slip directions will align with the modeled fault slip directions, some smaller earthquakes may be anomalous due to local stresses in the Earth, and even large subduction zone earthquakes may not match the model if strain is partitioned onto multiple faults. Discrepancies between the model and the earthquake catalog could be used to refine the Global Block Model. A poster deriving from Special studies with Jack Loveless, Associate Professor of Geosciences.
Ibuki Sugiura ‘22J
The efficacy of the brGDGT biomarker as a paleotemperature proxy – reconstruction of past temperature in Tasmania, Australia from lake sediments.This project has reconstructed past temperature from samples of a sediment core using the brGDGT (branched glycerol dialkyl glycerol tetraether) paleotemperature proxy. The Darwin Crater was chosen as our study site since the sediment record found there spans approximately the last 800,000 years, consisting of multiple glacial-interglacial cycles, and thus, is a powerful archive for paleoclimatic reconstructions. Our results, which successfully describe the changes in past temperature during the transition from a glacial period to an interglacial period, contribute to the further understanding of the paleoclimate and paleoenvironment in Tasmania and reinforce the scientific community’s understanding of brGDGTs as a proxy for temperature. A poster deriving from Special studies with Gregory de Wet, Assistant Professor of Geosciences.
Wayne Ndlovu ’22
Effects of Road Salt on Water and Soil Geochemistry of Wetlands in Western-central Massachusetts. De-icing salt (NaCl) applied to roads can elevate Na+ and Cl- concentrations in nearby soils and water bodies through surface runoff and groundwater recharge.Wetlands adjacent to these roads retain this salt. For this study, wetlands classified as either rain-fed true bogs or groundwater-fed acidic fens and freshwater marshes located close to major and minor roads were sampled. Surface water, groundwater and peat/organic mud samples were collected from the true bogs (Arcadia Bog (AB) and Mill Valley Road Bog (MVRB) of Belchertown), acidic fens (Trout Brook wetland (TB) and Quag Bog (QB) of Templeton and Gardiner), freshwater marshes (Fitzgerald Lake (FL) and East Templeton Pond (ETP) of Northampton and Templeton) and vernal pool in Belchertown. Field measurements and major ion chemistry data show that NaCl contamination is higher in acidic fens and freshwater marshes because of groundwater recharge and their closer proximity to major roads. Lower Na+ and Cl- concentrations were recorded in true bogs. While a 1:1 relationship between Na+ and Cl- is expected in the road salt contaminated water samples, Cl- concentrations are higher by ~20% suggesting that Na+ is adsorbed onto the negatively charged exchange sites in the peat or organic mud. The total cation exchange capacity (CEC) of the peat and organic-rich mud samples vary across the wetlands. Generally, true bogs and acidic fens have relatively higher CEC (22 cmolc/kg < CEC < 34 cmolc/kg). On the other hand, FL has the lowest CEC (12 cmolc/kg) while ETP has a CEC of 25 cmolc/kg. Calculated as charge fractions, H+ is the dominant exchangeable cation in true bogs (~60%) while exchangeable Ca2+ is dominant in acidic fens and freshwater marshes (~50%). Na+ charge fractions are highest at ETP (20%), followed by FL and QB (~6%), TB (3%) and < 0.15% in the true bogs (AB and MVRB). At all sites, Na+, Ca2+, Mg2+ and H+ charge fractions increase as their porewater chemistries increase which is an indication of adsorption. However, K+ is desorbed from the exchange sites lowering its charge fraction and increasing its concentration in the porewater. A poster deriving from SURF program with Prof. Amy Rhodes, Professor of Geosciences.
Cynthia Lan ’21
Finding Distance Between Quantal States in A Chaos System. A numerical method was developed to calculate the distance between two quantal states in a chaos system. The Wigner function was applied to formulate a quantal state at an arbitrary time, and given its quasi-distribution properties, the analogy of “sand pile” were used, the optimal transportation cost between the two sand piles was mathematically equivalent to the distance between the two quantal states by the definition of Monge distance. The concept of linear programming (LP) was applied to find the optimal cost with the SciPy Optimization package, and for special cases that can be calculated analytically, numerical solutions within 1% of percent error were able to be obtained. A poster deriving from SURF and Honors Thesis with Gary Felder, Professor of Physics.
JoyAnne Joseph ‘22, Natalie Morgan ‘24, Eyananda Ahmed ‘23 and Kadin Kristjansson ‘24
Comparing hot and cold stress in sea anemones (Aiptasia). We investigated the effect of temperature on the activity, health, and mortality of sea anemones (Aiptasia). As a model species for corals, these organisms are studied in both their symbiotic and aposymbiotic states, which can be achieved through bleaching. The mechanism for bleaching is not fully understood, though it is common thought that bleaching through cold temperatures (instead of hot) is less stressful on the organisms. To study this, we examined the difference between externally applied heat stress and cold stress on the physical response of the anemones to study whether one temperature had a more detrimental effect than the other. A poster derived from research work with Rachel Wright, Assistant Professor of Biological Sciences