thumbnail

Logs and data from trenches across the Hayward Fault at Tyson's Lagoon (Tule Pond), Fremont, Alameda County, California

Miscellaneous Field Studies Map 2386

By:
, , , , ,

Links

Abstract

INTRODUCTION The purpose of this publication is to make available detailed trench logs (sheets 1, 2), radiocarbon dates (table 1) and pollen data (fig. 1) obtained as a result of an intensive subsurface investigation of the Hayward Fault at Tyson's Lagoon (Tule Pond) from August to November 2000 (figs. 1, 2 on sheet 1). The Hayward Fault is recognized to be among the most hazardous in the United States (Working Group on California Earthquake Probabilities, 1999). This document makes available geologic evidence for historical and prehistoric surfacerupturing earthquakes that were recorded at the site. Prehistoric earthquakes deduced from geologic evidence are called paleoearthquakes. Establishing a chronology of paleoearthquakes is of immediate use in resolving the level of hazard posed by the Hayward Fault for producing large earthquakes in the future. Preliminary findings of this investigation have been presented in Lienkaemper and others (2001). A formal report on our conclusions based on these data is in preparation. The investigation at Tyson's Lagoon is ongoing, so these products should not be considered final. Lienkaemper, Dawson, and Personius interpreted the geology and logged the trenches. Seitz and Reidy performed analyses on radiocarbon and pollen samples, respectively. Schwartz led the critical-review field team. Previous trenching work was done at Tyson's Lagoon (figs. 2, 3 on sheet 1). Lienkaemper (1992) references the location of most of those trenches. The earlier trenching was generally for the evaluation of local faultrupture hazard, except for the study of Williams (1993), which was a paleoearthquake investigation. An unpublished study by J.N. Alt in 1998 (shown on our site map as trenches 98A and 98B, fig. 3, on sheet 1), also sought evidence of paleoearthquakes. Alt's study and one by Woodward-Clyde and Associates (1970; trenches 70A to 70G, fig. 3) were located south of Walnut Avenue in one of the few areas that still remain undisturbed and were, thus, useful in planning our work in 2000.

Geospatial Extents

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Logs and data from trenches across the Hayward Fault at Tyson's Lagoon (Tule Pond), Fremont, Alameda County, California
Series title:
Miscellaneous Field Studies Map
Series number:
2386
Edition:
-
Year Published:
2002
Language:
ENGLISH
Publisher:
Geological Survey (U.S.)
Contributing office(s):
Western Earthquake Hazards
Description:
2 Map Sheets: Sheet 1-45 x 30 inches, Sheet 2-33 x 44 inches; Pamphlet: 12 p.
Additional Online Files(Y/N):
Y