thumbnail

Field-trip guide to subaqueous volcaniclastic facies in the Ancestral Cascades arc in southern Washington State—The Ohanapecosh Formation and Wildcat Creek beds

Scientific Investigations Report 2017-5022-B

By:
and
https://doi.org/10.3133/sir20175022B

Links

Abstract

Partly situated in the idyllic Mount Rainier National Park, this field trip visits exceptional examples of Oligocene subaqueous volcaniclastic successions in continental basins adjacent to the Ancestral Cascades arc. The >800-m-thick Ohanapecosh Formation (32–26 Ma) and the >300-m-thick Wildcat Creek (27 Ma) beds record similar sedimentation processes from various volcanic sources. Both show evidence of below-wave-base deposition, and voluminous accumulation of volcaniclastic facies from subaqueous density currents and suspension settling. Eruption-fed facies include deposits from pyroclastic flows that crossed the shoreline, from tephra fallout over water, and from probable Surtseyan eruptions, whereas re-sedimented facies comprise subaqueous density currents and debris flow deposits.

Suggested Citation

Jutzeler, M., and McPhie, J., 2017, Field-trip guide to subaqueous volcaniclastic facies in the Ancestral Cascades arc in southern Washington State—The Ohanapecosh Formation and Wildcat Creek beds: U.S. Geological Survey Scientific Investigations Report 2017–5022–B, 24 p., https://doi.org/10.3133/sir20175022B.

ISSN: 2328-0328 (online)

Study Area

Table of Contents

  • Abstract
  • Introduction
  • Geologic Setting
  • Field-Trip Stops
  • References

Additional publication details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Field-trip guide to subaqueous volcaniclastic facies in the Ancestral Cascades arc in southern Washington State—The Ohanapecosh Formation and Wildcat Creek beds
Series title:
Scientific Investigations Report
Series number:
2017-5022
Chapter:
B
DOI:
10.3133/sir20175022B
Year Published:
2017
Language:
English
Publisher:
U.S. Geological Survey
Publisher location:
Reston, VA
Contributing office(s):
Volcano Science Center
Description:
vii, 24 p.
Country:
United States
State:
Washington
Other Geospatial:
Ancestral Cascades Arc, Ohanapecosh Formation, Wildcat Creek Beds
Online Only (Y/N):
Y