High-frequency river thorium monitoring

Knowledge graph centered on High-frequency river thorium monitoring with 20 nodes and 41 connections. Top connected: groundwater storage dynamics, spatiotemporal variability, concentration-discharge relationship, River thorium concentrations can record bedrock fr, critical zone.

Method synopsis

Frequent collection and ICP-MS analysis of river water samples to detect thorium concentration excursions as indicators of bedrock fracture processes. Samples collected up to daily frequency and analyzed for ultra-trace thorium concentrations.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure as described in the canonical source

Steps below were extracted from the paper that introduces this protocol — River thorium concentrations can record bedrock fracture processes including some triggered by distant seismic events (2023), Nature Communications. Implementations in other papers (listed below) may differ.

1. River water sample collection
   River water samples were collected frequently at the Pump House location on East River and at Coal Creek location, with collection frequency up to daily during 2016-2017 monitoring period
   Quantities: Multiple samples collected over 20 months from calendar years 2016-2017, with 22 thorium excursion episodes recorded at the PH siteDuration: Daily sampling during active monitoring periods from 2016-2017Conditions: Year-round sampling including different seasonal conditions and weather events
   Equipment: sample bottles, filtration equipment
2. Sample filtration and processing
   Stream and porewater samples were filtered in the field using 0.45 μm polyethersulfone syringe filters and divided into subsamples for different analyses. Subsamples for cation analysis were immediately acidified into 2% nitric acid
   Quantities: 0.45 μm filtration, 2% nitric acid concentration for acidificationDuration: Immediate processing in fieldConditions: Field conditions during sample collection
   Equipment: 0.45 μm polyethersulfone syringe filters, nitric acid
3. Laboratory analysis by ICP-MS
   Concentrations of Th, Zr, Be, As, Ca, K and other elements were analyzed using inductively coupled plasma mass spectrometer with method detection limits of 0.009, 0.05, 0.02 and 0.006 ppb for Th, Zr, Be and As respectively

Typical Equipment

• sample bottles
• 0.45 μm polyethersulfone syringe filters
• inductively coupled plasma mass spectrometer (ICP-MS)

Output Measurements

• thorium concentrations
• beryllium concentrations
• arsenic concentrations
• discharge measurements

Papers Using This Protocol (1)