Anisotropy of Magnetic Susceptibility (AMS)

Knowledge graph centered on Anisotropy of Magnetic Susceptibility (AMS) with 40 nodes and 119 connections. Top connected: Colorado River, thermal constraints, hypogene mineralization, hydraulic gradient, redox reactions.

Method synopsis

Oriented rock cubes are measured for directional magnetic susceptibility to determine fabric orientation and strength. Principal axes and confidence ellipses calculated using Jelinek statistics.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Post-Depositional Fluid Flow in Jurassic Sandstones of the Uncompahgre Uplift: Insights From Magnetic Fabrics (2020), Frontiers in Earth Science. Implementations in other papers (listed below) may differ.

1. Hand sample collection
   Hand samples with average dimension of 15 × 12 × 8 cm were collected from the Entrada Sandstone, Wanakah Formation, and Tidwell Member of the Morrison Formation using a rock hammer to obtain fresh surfaces and avoid supergene alteration overprints
   Quantities: Hand samples from two sites located 12 km apartDuration: Not specifiedConditions: Outcrop conditions in western Colorado
   Equipment: rock hammer, GPS units, magnetic compass
2. Sample georeferencing and orientation
   Geographic orientation of samples was determined using a magnetic compass after correction of magnetic declination (11°E)
   Quantities: All hand samples orientedDuration: Not specifiedConditions: Field conditions
   Equipment: magnetic compass, GPS units
3. Specimen preparation for AMS
   Several serial 2 cm-thick slabs were cut from hand samples, then 2 cm AMS cubes were cut side-by-side from these slabs to yield about 15 cubic specimen per hand sample. These oriented cubes were measured using the AGICO KLY-4S Kappabridge susceptibility meter
   Quantities: About 15 cubic specimens per hand sample Not specified

Typical Equipment

• rock hammer
• GPS units
• magnetic compass
• AGICO KLY-4S Kappabridge susceptibility meter

Output Measurements

• magnetic susceptibility axes
• degree of anisotropy
• shape factor

Papers Using This Protocol (1)

Places Where Used