Dr. J. Mark Erickson Geology University Fellows Endowment

In the summer of 2025, Rosemary examined organism interactions within shallow lagoons, analyzed carbonate sediment composition, and identified the key sediment producers and mapped lagoon-floor habitats. The research she completed contributes valuable insights into sediment dynamics, functioning ecosystems, and the enhancement of her knowledge of modern shallow-marine tropical environments. 

Each ring in a tree's trunk is a time capsule recording everything from temperature to streamflow in a given year. In the Adirondack Mountains, some Eastern Hemlocks (Tsuga canadensis) have been keeping this journal for more than 300 years! This summer, I cored 35 trees (16 hemlocks, 15 red spruce, and 4 black spruce) along the edge of Fox Fen, an ecologically sensitive wetland whose unique setting makes the trees especially sensitive to changes in climate.

Over the summer, I worked on a project with Dr. Nagel-Myers on the morphological changes in taxa found throughout the Eocene from Seymour Island in Antarctica. The Eocene was studied specifically for the temperature transition from a 'greenhouse' climate to an 'icehouse' climate. For this project, I focused on three different genera: Polinicies, Eurhomalea, and Saxolucina.

It has often been assumed that the presence of a magnetic field is necessary for the habitability of a planet, but is this true? Earth’s magnetic field is often thought to be vital in protecting the atmosphere from solar winds, but recent discoveries suggest that this might not be true. The aim of this project is to learn more about how the magnetic field affects atmospheric escape. To complete this project, I studied basalts. Basalts are a type of igneous rocks that form from volcanic eruptions.

The Early Jurassic Toarcian anoxic event (TOAE), also known as the Jenkyns event (~183 Mya), was one of the major Mesozoic episodes of global warming and carbon cycle perturbation that affected both oceanic and terrestrial environments. Here, we provide an example of how a shallow-marine carbonate platform setting responded to the global anoxia and its aftermath.

My research focus is on the exhumation of the Marcy Massif, a massive anorthosite-rich igneous body found in the high peaks of the Adirondacks. Old hypothesis explain that the anorthosite came up from the mantle in a diapiric, 'fist-like' way, though, due to recent reevaluations of how magma chambers act, this hypothesis is dated. Instead, it has been hypothesized that the Massif exhumed along fault lines. Testing this alternate theory included analyzing the strain of of bedrock along the borders of the Massif.

My research focused on the presence of microplastics in freshwater bivalves. Microplastics are everywhere, and my research explored how filter feeders, like clams, can be used to explore this topic. When collecting clams it was important to not use plastic tools or containers that could possibly impact the microplastic findings. Microplastics can be found in the clam’s tissue and the clam’s fecal matter. I worked with Dr. Oldacre and the chemistry department to dissolve the organic material leaving the microplastics behind.

For this project, I went out into the field and collected many different specimens of bivalves. I then had to identify these different specimens preferably down to their species level, but some specimens are not preserved well enough and genus level identification was then used. Next, I had to organize the occurrences of these different species to see who survives the late Devonian mass extinction. After compiling this data, I am able to create a sort of clear sense on what bivalve lineages survive or don't survive both Kellwasser events.

For my fellowship I worked with basaltic rock samples from Tenerife, the largest of the Canary Islands. I studied a possible hypothesis for the origin of low Mg# melts, that they originated as partial melts of an asthenospheric mantle source. The objective of this study is to evaluate temperature and dissolved water content of Tenerife basalts using olivine-melt thermometry/hygrometry. My research began with a trip to the Canary Islands where I collected the samples and began to study them.

Evidence of a glacier’s basal movement can be challenging to discover due to subsequent weathering and covering by the retreating glacier. Thanks to mineral prospecting, however, in Talcville, NY, an approximately 0.3-hectare site of striated talc-tremolite schist became exposed for striae analyses. This “pit”, geologically, is part of the greater Frontenac Axis, which geomorphologically represents a hectometer-scale, northeast-southwest ridge-and-valley system (cf. Miller and Stewart, 2014).

Over the last 50 years, Caribbean lagoons have undergone a major transformation from coral- to macroalgal-dominated habitats, coupled with a shift from historically dominant reef-building taxa to more opportunistic, stress-tolerant, non- framework building coral species. Although shallow lagoons protected by barrier reefs are well developed along the northern Jamaican coastline, studies documenting their biota, including major carbonate sediment producers are rare.

The advent of remote-sensing technologies (e.g., LiDAR) has been vital to understanding the Earth’s landscape.  The Alaskan transportation sector, for example, relies on these technologies to develop models to better understand landscape stability in Alaska (i.e., Miandad et al., 2020). These desktop models, however, require ground truthing to confirm their accuracy.  Based on a model developed by Miandad et al.

Alaska’s interior transportation corridors are susceptible to landslide events and are often burdened by excessive repair costs and prolonged repair time. The state requires a new model that can project long-term landscape stability given the constraints of a limited landslide inventory. Miandad et al. (2020) developed a remote sensing model using LiDAR and Normalized Difference Vegetation Index (NDVI) to identify slope stability.

Recent uplift of the Precambrian Adirondack (ADK) Mountains provides a glimpse into the center of the ancient orogenic belt of the Grenville Province. The ADK Highlands are dominated by the Anorthosite-Mangerite-Charnockite-Granite (AMCG) intrusive suite.  Structural and lithologic diversity in the ADK Highlands have been attributed to the effects of multiple orogenic events. The Marcy Anorthosite Massif, located within the ADK Highlands, is typically depicted as one homogenous geologic unit of metanorthosite and anorthosite gneiss.

St. Lawrence University is located in a geologically unique location close to the boundary of the Adirondack highlands and lowlands. In these waterways, insoluble elements systematically decrease downriver from the Adirondacks to the St. Lawrence Lowlands, while the water pH increases. Freshwater bivalves are threatened because of degradation of their habitats due to human activities. Anthropogenically induced changes in pH like for example due to acid rain are among the factors imperiling these organisms.

Coarse-woody debris (CWD) is a basic part of the forest-floor ecosystem and provides stabilization for topsoil and a habitat for various animals and fungi. Understanding differences in CWD across select Adirondack (ADK) lake basins may provide insight into forest dynamics and palaeoclimate work. As an extension of previous works by Freimuth et al. (2020), we selected four basins from their work to evaluate CWD within their catchments: Debar Pond (DP), Moose Pond (MP), Heart Lake (HL), and East Pine Pond (EPP).