cap rock

American  

Or caprock

noun

Geology.

1. a mass of anhydrite, gypsum, or limestone immediately above the salt of a salt dome.

2. an impervious stratum overlying an oil- or gas-bearing structure.

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cap rock British  

noun

1. a layer of rock that overlies a salt dome and consists of limestone, gypsum, etc

2. a layer of relatively impervious rock overlying an oil- or gas-bearing rock

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Etymology

Origin of cap rock

An Americanism dating back to 1865–70

Example Sentences

By 5:30 p.m., our class of five was gathered in the Cap Rock parking lot — one of the lots that stays open at night for stargazers.

From Los Angeles Times

After a reminder to bring water and a rundown of Cap Rock Trail, which is a 0.4-mile loop with a bathroom near the parking lot, Norris led us onto the trail to start planning our shots.

From Los Angeles Times

Hiking a social trail behind Joshua Tree National Park’s famed Cap Rock, I came across a peculiar sight that, if you know what you’re looking for, actually isn’t so unusual at all: a crude cross made of dark stones below a scribble of orange graffiti.

From Los Angeles Times

According to Kaufman and several rangers, the body was cremated on a median bordering the Cap Rock parking lot.

From Los Angeles Times

Spokesperson Jennie Albrinck said National Park Service officials are discussing a music-related exhibit at Cap Rock that would spotlight Native American bird singers, Parsons and emerging artists performing at music festivals such as Coachella and Stagecoach today.

From Los Angeles Times