law of superposition

American  

noun

1. Geology. a basic law of geochronology, stating that in any undisturbed sequence of rocks deposited in layers, the youngest layer is on top and the oldest on bottom, each layer being younger than the one beneath it and older than the one above it.

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law of superposition Scientific  

1. See superposition

2. Geology A general law stating that in any sequence of sediments or rocks that has not been overturned, the youngest sediments or rocks are at the top of the sequence and the oldest are at the bottom.

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Example Sentences

By means of the law of included organisms and the law of superposition the formations of different countries and continents are correlated and arranged in their natural order.

From The Elements of Geology by Norton, William Harmon

Nor can the law of superposition be used in identifying and comparing the strata of different regions where the formations cannot be traced continuously from one region to the other.

From The Elements of Geology by Norton, William Harmon

The chart given on page 295 is thus based on the law of superposition and the law of the evolution of organisms.

From The Elements of Geology by Norton, William Harmon