Revisiting the Tectonic Geomorphology of the Nicaragua Segment of the Middle America Trench Using Newly Collected High-resolution Bathymetry and Reprocessed Marine Seismic Reflection Data
The Nicaragua segment of the Middle America Trench hosted a devastating tsunami earthquake in 1992, but land-based geodetic studies have not identified an associated locked patch along the megathrust. Because modeled slip varies across studies, understanding fault geometries near the trench and their lateral continuity can add important context to understanding tsunami generation at the margin. Here, we present tectonic and geomorphic analysis of new high-resolution bathymetric data collected in 2025 aboard the R/V Atlantis. Combined with reprocessed multichannel seismic reflection data collected in 2000 aboard the R/V Ewing,these data allow us to better constrain lateral continuity of structural features. Using a high-pass spatial filter on the bathymetry, we identify a change in the wavelength of structures from the lower to mid slope and correlate these geomorphic structures with their subsurface expressions along strike. The lower slope structure is comprised of laterally continuous slope and bench pairs, that appear to mimic the incoming plate structure. The upper and mid slopes are characterized by shorter wavelength structures that appear less laterally continuous and are likely related to overriding plate structures. Understanding the lateral continuity of these subsurface features is an important step toward understanding the seismic and tsunami hazard along this margin, and it will provide important context for seafloor geodetic observations currently being collected in this region.
Session: Linking Subduction Zone Processes and Cascading Hazards in Alaska, Cascadia, Chile and Beyond [Poster]
Type: Poster
Room: Exhibit Hall A+B
Date: 4/16/2026
Presentation Time: 08:00 AM (local time)
Presenting Author: Sarah Rysanek
Student Presenter: Yes
Invited Presentation:
Poster Number: 132
Additional Authors
Sarah Rysanek Presenting Author Corresponding Author srysanek@unm.edu University of New Mexico |
Eric Lindsey eol@unm.edu University of New Mexico |
Lindsay Worthington lworthington@unm.edu University of New Mexico |
Surui Xie sxie9@central.uh.edu University of Houston |
Mark Zumberge mzumberge@ucsd.edu University of California, San Diego |
Timothy Dixon thd@usf.edu University of South Florida |
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Revisiting the Tectonic Geomorphology of the Nicaragua Segment of the Middle America Trench Using Newly Collected High-resolution Bathymetry and Reprocessed Marine Seismic Reflection Data
Category
Linking Subduction Zone Processes and Cascading Hazards in Alaska, Cascadia, Chile and Beyond
Description