Stanford Cosmogenic Isotope Lab Jane Willenbring (Supervising PI)

Stanford Cosmogenic Isotope Laboratory

View of the front of Stanford Campus

Cosmogenic Isotope Laboratory

Meteoric and In-Situ ¹⁰Be and ²⁶Al Analysis

Welcome

Our Cosmogenic Isotope Laboratory specializes in the extraction and purification of the terrestrial cosmogenic nuclides beryllium-10 (¹⁰Be) and aluminum-26 (²⁶Al). These rare radionuclides serve as powerful chronometers and tracers, enabling us to reconstruct Earth-surface processes across timescales ranging from thousands to millions of years. New users are encouraged to discuss their project with the lab director, Jane Willenbring, and the lab manager, Caroline Harmon, to sample appropriately. 

Scientific Foundation

Cosmogenic nuclides are produced through the interaction of high-energy secondary cosmic-ray particles with target atoms in the atmosphere and in minerals at or near the Earth's surface. Our laboratory focuses on two distinct production pathways:

In-Situ Production Nuclides produced within mineral lattices—primarily quartz (SiO₂)—through spallation and muon-induced reactions on oxygen, silicon, and aluminum. Because production rates are well-characterized and decrease predictably with mass-depth, in-situ ¹⁰Be and ²⁶Al are invaluable for quantifying:

  • Bedrock and catchment-wide erosion and chemical weathering rates
  • Surface exposure ages of glacial, fluvial, and tectonic landforms
  • Burial ages of sediments and cave deposits (using the ²⁶Al/¹⁰Be ratio)

Meteoric (Atmospheric) Production Nuclides generated in the atmosphere that are subsequently delivered to Earth's surface via precipitation and dry deposition. Meteoric ¹⁰Be adsorbs readily onto soil particles and sediments, making it a sensitive tool for:

  • Soil residence times and pedogenic processes
  • Sediment provenance and transport dynamics
  • Chronologies of soils, marine, and lacustrine records

The ²⁶Al/¹⁰Be Dual-Nuclide System

The complementary behavior of ²⁶Al and ¹⁰Be—with distinct half-lives (~717,000 and ~1.39 million years, respectively) and a well-constrained production ratio depending on local altitude and latitude—allows us to disentangle complex exposure and burial histories that a single nuclide cannot resolve. The ²⁶Al/¹⁰Be ratio reveals whether a sample has a simple one-stage history or a complex exposure/burial history.

RRID information: https://scicrunch.org/resolver/SCR_025082