Data release for fault activity in the San Gabriel Mountains, USA: insights from landscape morphometrics, erosion rates, and fault-slip rates (ver. 2.0, November 2023)

This report summarizes geomorphic data and analysis from the range front and interior of the San Gabriel Mountains, California, USA. For catchment-average erosion rates, we describe the methodology used to collect samples of detrital sediment, determine concentrations of cosmogenic beryllium-10 in purified quartz isolated from the samples, and use those nuclide concentrations to calculate erosion rates. We also describe the methodology for calculating various topographic metrics from previously published lidar topographic data. These metrics include stream channel concavity, normalized channel steepness index, dimensionless hilltop erosion and dimensionless hilltop relief.

This data release includes a total of seven data files, formatted as comma separated values. Two files refer to the beryllium-10 erosion rates: "AMS...csv" and "EROSION...csv" (see Process Step 1). The file titled "MORPHOMETRICS...csv" summarizes landscape morphometric results (See Process Steps 2-4). The two files "CHI_SEG_RANGEFRONT...csv" and "CHI_SEG_INTERIOR...csv" provide the results from the algorithm LSDTopoTools (See Process Step 3) for stream channels, including normalized steepness results from the segmentation algorithm for every stream channel in this analysis. The two files "CHI_PIX_RANGEFRONT...csv" and "CHI_PIX_INTERIOR...csv" provide the results from the algorithm LSDTopoTools (See Process Step 3) for stream channels, including normalized steepness results calculated pixel-by-pixel for every stream channel in this analysis.The term "range front" refers to catchments the flow across the Sierra Madre-Cucmonga fault zone, whereas the term "interior" refers to the catchments located north of the fault zone and flowing into a larger trunk stream without crossing the fault zone. The file "README.txt" summarizes the methods used to produce these data, and the file "METADATA...csv" contains detailed information about each data field