Year of Award
Master of Science (MS)
Department or School/College
Hilary Martens, Jesse Johnson
Nancy Hinman, Hilary Martens, Jesse Johnson
stromatolites, biosignatures, fractals, astrobiology, diffusion-limited aggregation, modeling
University of Montana
Biogeochemistry | Other Microbiology | Paleontology
Stromatolites, microbialites, and other microbially induced sedimentary structures exist in the rock record as far back as 3.6 billion years ago and continue to form in the present day. Better characterizing these structures and better understanding how they form is crucial in distinguishing these biosignatures from similar, abiotic structures, which can help us to understand the conditions of early Earth and early Mars. To that end, I have modified DLA 3D EXT, an open-source stromatolite modeling program, to more closely reflect the process of microbial trapping-and-binding by filamentous microbes in a calcite-precipitating hot spring system. This modified program includes a field of upright spikes that can trap incoming particles and sediment. I simulated stromatolites forming with different spike heights, spike spacings, and stickiness. To quantify these stromatolites’ morphologies, I obtained the fractal dimension and lacunarity of a section of each resulting structure. I found that stickiness affects morphology as measured by both fractal dimension and lacunarity. This may help us better distinguish true stromatolites from abiotic imposters.
Stevens, Laura E., "Modeling Stromatolite Formation with Diffusion-Limited Aggregation" (2021). Graduate Student Theses, Dissertations, & Professional Papers. 11766.
© Copyright 2021 Laura E. Stevens