[ESS] Kim Huppert (CUNY)

Note: special Thursday talk date

“Rain, rivers, and reefs”

Volcanic ocean islands are well suited for studying climatic controls on erosion because they typically have relatively homogeneous bedrock, steep rainfall gradients, and remnant surfaces that constrain their age, initial topography, and vertical motions relative to sea level. They also often host coral reefs, which protect coastal communities and infrastructure from storms, floods, and rising sea levels. In this talk, I’ll examine the influence of rainfall and discharge variability on bedrock river incision on the Hawaiian Island of Kaua‘i. I’ll also present a new compilation of river incision efficiencies inferred from eroded canyon volumes and lava flow ages across the Azores, Hawaiian, and Canary Islands. These erosional efficiencies increase with mean annual rainfall over nearly the full range of rainfall rates experienced on Earth. Yet, the scaling between rainfall and erosion rates varies between island chains. I’ll discuss some possible explanations for these discrepancies in climatic control and consider the implications on couplings between orogeny and orography. In the second part of the talk, I’ll examine controls on coral reef widening under relative sea level rise and present a non-dimensional framework for mapping out environmental influences on reef development.

Malatesta, L. C., Finnegan, N. J., Huppert, K. L., & Carreño, E. I. (2022). The influence of rock uplift rate on the formation and preservation of individual marine terraces during multiple sea-level stands. Geology, 50(1), 101-105, https://doi.org/10.1130/G49245.1

Earth Science Seminar —

Lecture portion of the EAPS graduate-level class 12.571, covering current research in geophysics, geology, geochemistry, and geobiology. All members of the MIT community are welcome to join for presentations by guest speakers, held approximately every two weeks during the term.

Contact: earth-science-seminar-info@mit.edu