Origin of Unconsolidated Quaternary Deposits at Harriet Point near Redoubt Volcano, Alaska

Scientific Investigations Report 2021-5071



Unconsolidated boulder-rich diamicton units exposed in sea cliffs at Harriet Point southeast of Redoubt Volcano were evaluated to better understand their provenance relative to the late Quaternary eruptive history of the volcano. A previous study concluded that deposits at Harriet Point were emplaced by a large volcanic landslide originating on the southeast flank of Redoubt Volcano (Begét and Nye, 1994). Field-based analysis of the stratigraphy and sedimentology of the Harriet Point deposits and numerical simulations of the volcanic landslide area of inundation indicate that none of the deposits are volcanogenic. All of the unconsolidated boulder-rich diamicton units at Harriet Point are glacial in origin and can be reconciled using the presently available model for late Quaternary glaciation of Cook Inlet.

Suggested Citation

Waythomas, C.F., 2021, Origin of unconsolidated Quaternary deposits at Harriet Point near Redoubt Volcano, Alaska: U.S. Geological Survey Scientific Investigations Report 2021-5071, 14 p., https://doi.org/10.3133/sir20215071.

ISSN: 2328-0328 (online)

Study Area

Table of Contents

  • Abstract  
  • Introduction  
  • Deposits at Harriet Point  
  • Stratigraphy and Interpretation of Deposits at Harriet Point  
  • Depositional Model for Harriet Point Deposits  
  • Reevaluation of Harriet Point Debris-Avalanche Deposit  
  • Summary  
  • Acknowledgments  
  • References Cited 
Publication type Report
Publication Subtype USGS Numbered Series
Title Origin of unconsolidated Quaternary deposits at Harriet Point near Redoubt Volcano, Alaska
Series title Scientific Investigations Report
Series number 2021-5071
DOI 10.3133/sir20215071
Year Published 2021
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Alaska Volcano Observatory, Volcano Science Center
Description iv, 14 p.
Country United States
State Alaska
Other Geospatial Harriet Point, Redoubt Volcano
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details