Is there a discrepancy between geological and geodetic slip rates along the San Andreas Fault System?

2014 ◽  
Vol 119 (3) ◽  
pp. 2518-2538 ◽  
Author(s):  
Xiaopeng Tong ◽  
Bridget Smith‐Konter ◽  
David T. Sandwell
Keyword(s):  
San Andreas Fault ◽  
Fault System ◽  
Slip Rates ◽  
San Andreas ◽  
San Andreas Fault System

scholarly journals Chlorine-36/beryllium-10 burial dating of alluvial fan sediments associated with the Mission Creek strand of the San Andreas Fault system, California, USA

2019 ◽  
Author(s):  
Greg Balco ◽  
Kimberly Blisniuk ◽  
Alan Hidy
Keyword(s):  
San Andreas Fault ◽  
Alluvial Fan ◽  
Fault System ◽  
Middle Pleistocene ◽  
Slip Rates ◽  
San Bernardino Mountains ◽  
Production Ratio ◽  
San Andreas ◽  
San Andreas Fault System ◽  
Middle And Late Pleistocene

Abstract. We apply cosmogenic-nuclide burial dating using the 36Cl-in-K-feldspar/10Be-in-quartz pair in fluvially transported granitoid clasts to determine the age of alluvial sediment displaced by the Mission Creek strand of the San Andreas Fault in southern California. Because the half-lives of 36Cl and 10Be are more different than those of the commonly used 26Al/10Be pair, 36Cl/10Be burial dating should be applicable to sediments in the range ca. 0.2–0.5 Ma that are too young to be accurately dated with the 26Al/10Be pair, and should theoretically be more precise for middle and late Pleistocene sediments in general. However, using the 36Cl/10Be pair is more complex because the 36Cl/10Be production ratio varies with the chemical composition of each sample. We use 36Cl/10Be measurements in samples of granodiorite exposed at the surface at present to validate calculations of the 36Cl/10Be production ratio in this lithology, and then apply this information to determine the burial age of alluvial clasts of the same lithology. This particular field area presents the additional obstacle to burial dating (which is not specific to the 36Cl/10Be pair, but would apply to any) that most buried alluvial clasts are derived from extremely rapidly eroding parts of the San Bernardino Mountains and have correspondingly extremely low nuclide concentrations, the majority of which most likely derives from nucleogenic (for 36Cl) and post-burial production. Although this precludes accurate burial dating of many clasts, data from surface and subsurface samples with higher nuclide concentrations, originating from lower-erosion-rate source areas, show that upper Cabezon Formation alluvium is 260 ka. This is consistent with stratigraphic age constraints as well as independent estimates of long-term fault slip rates, and highlights the potential usefulness of the 36Cl/10Be pair for dating upper and middle Pleistocene clastic sediments.

High Geologic Slip Rates since Early Pleistocene Initiation of the San Jacinto and San Felipe Fault Zones in the San Andreas Fault System: Southern California, USA

2011 ◽  
Author(s):  
Susanne U. Janecke ◽  
Rebecca J. Dorsey ◽  
David Forand ◽  
Alexander N. Steely ◽  
Stefan M. Kirby ◽  
...  
Keyword(s):  
Southern California ◽  
San Andreas Fault ◽  
Fault Zones ◽  
Early Pleistocene ◽  
Fault System ◽  
Slip Rates ◽  
San Andreas ◽  
San Andreas Fault System

scholarly journals Chlorine-36∕beryllium-10 burial dating of alluvial fan sediments associated with the Mission Creek strand of the San Andreas Fault system, California, USA

Geochronology ◽  
2019 ◽  
Vol 1 (1) ◽  
pp. 1-16
Author(s):  
Greg Balco ◽  
Kimberly Blisniuk ◽  
Alan Hidy
Keyword(s):  
San Andreas Fault ◽  
Alluvial Fan ◽  
Fault System ◽  
Middle Pleistocene ◽  
Slip Rates ◽  
San Bernardino Mountains ◽  
Production Ratio ◽  
San Andreas ◽  
San Andreas Fault System ◽  
Middle And Late Pleistocene

Abstract. We apply cosmogenic-nuclide burial dating using the 36Cl-in-K-feldspar∕10Be-in-quartz pair in fluvially transported granitoid clasts to determine the age of alluvial sediment displaced by the Mission Creek strand of the San Andreas Fault in southern California. Because the half-lives of 36Cl and 10Be are more different than those of the commonly used 26Al∕10Be pair, 36Cl∕10Be burial dating should be applicable to sediments in the range ca. 0.2–0.5 Ma, which is too young to be accurately dated with the 26Al∕10Be pair, and should be more precise for Middle and Late Pleistocene sediments in general. However, using the 36Cl∕10Be pair is more complex because the 36Cl∕10Be production ratio varies with the chemical composition of each sample. We use 36Cl∕10Be measurements in samples of granodiorite exposed at the surface at present to validate calculations of the 36Cl∕10Be production ratio in this lithology, and then we apply this information to determine the burial age of alluvial clasts of the same lithology. This particular field area presents the additional obstacle to burial dating (which is not specific to the 36Cl∕10Be pair, but would apply to any) that most buried alluvial clasts are derived from extremely rapidly eroding parts of the San Bernardino Mountains and have correspondingly extremely low nuclide concentrations, the majority of which most likely derive from nucleogenic (for 36Cl) and post-burial production. Although this precludes accurate burial dating of many clasts, data from surface and subsurface samples with higher nuclide concentrations, originating from lower-erosion-rate source areas, show that the age of upper Cabezon Formation alluvium is 260 ka. This is consistent with stratigraphic age constraints as well as independent estimates of long-term fault slip rates, and it highlights the potential usefulness of the 36Cl∕10Be pair for dating Upper and Middle Pleistocene clastic sediments.

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