New Constraints on Deformation, Slip Rate, and Timing of the Most Recent Earthquake on the West Tahoe-Dollar Point Fault, Lake Tahoe Basin, California

High-resolution seismic compressed high intensity Radar pulse (CHIRP) data and piston cores acquired in Fallen Leaf Lake (FLL) and Lake Tahoe provide new paleoseismic constraints on the West Tahoe-Dollar Point fault (WTDPF), the western- most normal fault in the Lake Tahoe Basin, California. Paleoearthquake records along three sections of the WTDPF are investigated to determine the magnitude and recency of coseismic slip. CHIRP profiles image vertically offset and folded strata along the southern and central sections that record deformation associated with the most recent event (MRE) on the WTDPF. Three faults are imaged beneath FLL, and the maximum vertical offset observed across the primary trace of the WTDPF is ∼3:7 m. Coregis- tered piston cores in FLL recovered sediment and organic material above and below the MRE horizon. Radiocarbon dating of organic material constrained the age of the MRE to be between 3.6 and 4.9 k.y. B.P., with a preferred age of 4.1-4.5 k.y. B.P. In Lake Tahoe near Rubicon Point, approximately 2.0 m of vertical offset is observed across the WTDPF. Based on nearby core data, the timing of this offset occurred be- tween ∼3-10 k:y: B.P., which is consistent with the MRE age in FLL. Offset of Tioga- aged glacial deposits provides a long-term record of vertical deformation on the WTDPF since ∼13-14 k:y: B.P., yielding a slip rate of 0:4-0:8 mm=yr. In summary, the slip rate and earthquake potential along the WTDPF is comparable to the nearby Genoa fault, making it the most active and potentially hazardous fault in the Lake Tahoe Basin.

[1]  J. Dingler New geophysical approaches to study neotectonics and associated geohazards , 2007 .

[2]  W. Hammond,et al.  Crustal deformation across the Sierra Nevada, northern Walker Lane, Basin and Range transition, western United States measured with GPS, 2000–2004 , 2007 .

[3]  Steven G. Wesnousky,et al.  Predicting the endpoints of earthquake ruptures , 2006, Nature.

[4]  R. Briggs,et al.  Late Pleistocene and Holocene Paleoearthquake Activity of the Olinghouse Fault Zone, Nevada , 2005 .

[5]  N. Hinz,et al.  Kinematics of the northern Walker Lane: An incipient transform fault along the Pacific–North American plate boundary , 2005 .

[6]  M. Beres,et al.  Seismic stratigraphy, buried beach ridges and contourite drifts: the Late Quaternary history of the closed Lago Cardiel basin, Argentina (49°S) , 2004 .

[7]  Geoffrey Blewitt,et al.  Evidence for Deep Magma Injection Beneath Lake Tahoe, Nevada-California , 2004, Science.

[8]  William C. Hammond,et al.  Contemporary tectonic deformation of the Basin and Range province, western United States: 10 years of observation with the Global Positioning System , 2004 .

[9]  R. Briggs,et al.  Late Pleistocene fault slip rate, earthquake recurrence, and recency of slip along the Pyramid Lake fault zone, northern Walker Lane, United States , 2004 .

[10]  J. Bell,et al.  Pattern and Rates of Faulting in the Central Nevada Seismic Belt, and Paleoseismic Evidence for Prior Beltlike Behavior , 2004 .

[11]  J. Oldow Active transtensional boundary zone between the western Great Basin and Sierra Nevada block, western U.S. Cordillera , 2003 .

[12]  R. Bennett,et al.  Contemporary strain rates in the northern Basin and Range province from GPS data , 2003 .

[13]  J. Humphrey,et al.  Transtensional model for the Sierra Nevada frontal fault system, eastern California , 2003 .

[14]  Kenneth D. Smith,et al.  Source Parameters of Eastern California and Western Nevada Earthquakes from Regional Moment Tensor Inversion , 2003 .

[15]  J. C. Savage,et al.  Strain accumulation and rotation in western Nevada, 1993–2000 , 2002 .

[16]  D. Stockli,et al.  Two‐phase westward encroachment of Basin and Range extension into the northern Sierra Nevada , 2002 .

[17]  D. Argus,et al.  Present tectonic motion across the Coast Ranges and San Andreas fault system in central California , 2001 .

[18]  C. Henry,et al.  Sierra Nevada-Basin and Range transition near Reno , 2001 .

[19]  J. Bischoff,et al.  Wisconsin Glaciation of the Sierra Nevada (79,000–15,000 yr B.P.) as Recorded by Rock Flour in Sediments of Owens Lake, California , 2001, Quaternary Research.

[20]  James V. Gardner,et al.  Morphology and processes in Lake Tahoe (California-Nevada) , 2000 .

[21]  John G. Anderson,et al.  The potential hazard from tsunami and Seiche waves generated by large earthquakes within Lake Tahoe, California‐Nevada , 2000 .

[22]  Meghan S. Miller,et al.  Present‐day motion of the Sierra Nevada block and some tectonic implications for the Basin and Range province, North American Cordillera , 2000 .

[23]  Craig M. dePolo,et al.  Large-magnitude, late Holocene earthquakes on the Genoa fault, west-central Nevada and eastern California , 1999, Bulletin of the Seismological Society of America.

[24]  D. Stow,et al.  Seismic features diagnostic of contourite drifts , 1999 .

[25]  Stuart Hardy,et al.  Kinematic modelling of extensional fault-propagation folding , 1999 .

[26]  Kenneth D. Smith,et al.  The Seismotectonics of the 30 October 1998 Incline Village, Nevada Earthquake and Its Effects , 1999 .

[27]  Kenneth D. Smith,et al.  Preliminary Fault Map of the Lake Tahoe Basin, California and Nevada , 1999 .

[28]  E. Hearn,et al.  Kinematics of the southern Walker Lane Belt and motion of the Sierra Nevada block, California , 1998 .

[29]  M. Kashgarian,et al.  Continuous Lake-Sediment Records of Glaciation in the Sierra Nevada between 52,600 and 12,50014C yr B.P , 1998, Quaternary Research.

[30]  N. Driscoll,et al.  Sedimentary processes across the continental rise of the southern Antarctic Peninsula , 1997 .

[31]  John R. Underhill,et al.  Linked sequence stratigraphic and structural evolution of propagating normal faults , 1997 .

[32]  M. Belardinelli,et al.  Static stress changes in extensional regimes: An application to southern Apennines (Italy) , 1997, Bulletin of the Seismological Society of America.

[33]  M. Plummer,et al.  Chronology for Fluctuations in Late Pleistocene Sierra Nevada Glaciers and Lakes , 1996, Science.

[34]  N. Driscoll,et al.  Abyssal current influence on the southwest Bermuda Rise and surrounding region , 1996 .

[35]  D. Wells,et al.  New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacement , 1994, Bulletin of the Seismological Society of America.

[36]  Susan Lindstrom Submerged Tree Stumps as Indicators of Mid-Holocene Aridity in the Lake Tahoe Region , 1990 .

[37]  C. Scholz The Mechanics of Earthquakes and Faulting , 1990 .

[38]  R. Bucknam,et al.  Surface faulting accompanying the Borah Peak earthquake and segmentation of the lost river fault, central Idaho , 1987 .

[39]  C. Bacon Eruptive history of Mount Mazama and Crater Lake Caldera, Cascade Range, U.S.A. , 1983 .

[40]  H. Kanamori,et al.  A moment magnitude scale , 1979 .

[41]  James E. Court,et al.  Quaternary History of Lake Tahoe, California-Nevada , 1972 .

[42]  P. Birkeland Pleistocene Volcanism and Deformation of the Truckee Area, North of Lake Tahoe, California , 1963 .

[43]  Irving J. Witkind,et al.  Geologic features of the earthquake at Hebgen Lake, Montana, August 17, 1959 , 1962 .

[44]  Richard A. Schweickert,et al.  60 k.y. record of extension across the western boundary of the Basin and Range province: Estimate of slip rates from offset shoreline terraces and a catastrophic slide beneath Lake Tahoe , 2006 .

[45]  E. Ford,et al.  Geologic Map of the Lake Tahoe Basin, California and Nevada , 2005 .

[46]  Caitlin E. Buck,et al.  Intcal04 Terrestrial Radiocarbon Age Calibration, 0–26 Cal Kyr BP , 2004, Radiocarbon.

[47]  Christopher Bronk Ramsey,et al.  DEVELOPMENT OF THE RADIOCARBON CALIBRATION PROGRAM , 2001 .

[48]  A. Gillespie,et al.  Timing and significance of Late-glacial and Holocene cirque glaciation in the Sierra Nevada, California , 1997 .

[49]  Christopher Bronk Ramsey,et al.  Radiocarbon Calibration and Analysis of Stratigraphy: The OxCal Program , 1995, Radiocarbon.

[50]  A. Sarna‐Wojcicki,et al.  Tephrochronologic correlation of upper Neogene sediments along the Pacific margin, conterminous United States , 1991 .

[51]  M. Stuiver,et al.  Discussion Reporting of 14C Data , 1977, Radiocarbon.