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septarian

American  
[sep-tair-ee-uhn] / sɛpˈtɛər i ən /
Rarely septariate

adjective

Geology.
  1. being or relating to a septarium, a nodule or mass of limestone, ironstone, etc., with a network of cracks inside it filled with calcite and other minerals.

    The creation of these septarian concretions began about 60 million years ago when muddy sediment slowly accumulated on the seafloor.


Etymology

Origin of septarian

First recorded in 1815–25; septari(um) ( def. ) + -an ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The London Clay, 500 ft. thick, is a marine deposit consisting of blue or brown clay with sandy layers and septarian nodules; its equivalent in the Hampshire area is sometimes called the Bognor Clay, well exposed on the coast of Sussex.

From Project Gutenberg

A little above the oyster bed is a band of hard-bluish septarian limestone.

From Project Gutenberg

Another type of concretion, very abundant in many clays and shales, is the “septarian nodule.”

From Project Gutenberg

This recalls the occurrence of fossils in septarian nodules, flints, phosphatic concretions, &c., in the older strata.

From Project Gutenberg

Many shales contain great numbers of ovoid or rounded septarian nodules of clay ironstone.

From Project Gutenberg