Isochron
noun ·Rare ·Advanced level
Definitions
- 1 A line on a chart linking rock of the same age (as determined from isotope ratios).
"Recapitulating, any suite of comagmatic rocks with an age t defines an isochron if its members all had the same initial ^{₈₇}Sr/^{₈₆}Sr ratio and if it was closed to both Rb and Sr since crystallization occurred and neither element was introduced from any extraneous source.[…]In this way, whole-rock Rb-Sr isochrons can produce rather reliable age data for rock samples."
- 2 A collection of points (such as a manifold), each point representing a set of initial conditions for a given dynamical system, such that every set results in the same long-term behaviour of the system.
"The entire plane is foliated by isochrons."
Example
More examples"Recapitulating, any suite of comagmatic rocks with an age t defines an isochron if its members all had the same initial ^{₈₇}Sr/^{₈₆}Sr ratio and if it was closed to both Rb and Sr since crystallization occurred and neither element was introduced from any extraneous source.[…]In this way, whole-rock Rb-Sr isochrons can produce rather reliable age data for rock samples."
Etymology
From iso- + chron.
Related phrases
More for "isochron"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.