basement complex

American  

noun

Geology.

1. the undifferentiated assemblage of rock basementrock underlying the oldest stratified rocks in any region: usually crystalline, metamorphosed, and mostly, but not necessarily, Precambrian in age.

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Etymology

Origin of basement complex

First recorded in 1895–1900

Example Sentences

By 2:30 p.m., police ordered a full evacuation to secure rooms outside the Capitol, prompting an underground race through the basement complex.

From Washington Post

I failed to uncover either critical Republican senator during numerous strolls through the winding basement complex that I took throughout the day, but found Collins’ spokeswoman and asked if her boss would be coming through too.

From Slate

Williams wants to put in a basement complex which will come perilously close to Tower House.

From The Guardian

In certain localities, for example, the Cambrian rocks rest unconformably on a surface of metamorphic and igneous rocks—that is, the Basement Complex was raised above sea-level, eroded and subsequently depressed before the Cambrian sediments were laid upon it.

From Project Gutenberg

In general, this has been found to be true, as is suggested by the fact that to the pre-Cambrian metamorphosed terranes, as previously stated, the name Basement Complex has been applied.

From Project Gutenberg