Definition of outcrop in US English:



  • A rock formation that is visible on the surface.

    ‘dramatic limestone outcrops’
    • ‘Vistas of mountains and valleys with interesting weathered limestone outcrops are everywhere, and there are numerous small mines.’
    • ‘On land, scientists may collect samples from rock outcrops.’
    • ‘The main outcrops of this rock suite underlie the two steep-sided hills of the Boesmanskop to the immediate north of the main escarpment.’
    • ‘Surrounding this lowlying area are ‘horsts’ of Palaeozoic rocks, and outcrops of Triassic conglomerates that drain into the basins of the Trent, Warwickshire Avon and the Severn.’
    • ‘Traces of these explorations are still visible in the rocky outcrops on the ridge.’
    • ‘Around 110 km north of Arming there is a series of further outcrops of Lower Cambrian rocks.’
    • ‘Topographic and geological maps are the next stop to identify likely areas based on physical features such as sinkholes, known outcrops of cave forming rocks, and known cave locations.’
    • ‘As a boy, he loved to explore the teeming streets of Manhattan and South Bronx, checking out street excavations and rock outcrops in public parks for minerals.’
    • ‘Scattered throughout the Mojave Desert, outcrops of Proterozoic sedimentary rock make up parts of the mountain ranges that divide this region into basins.’
    • ‘He has also gone further afield including BC and Alberta in Canada, Utah, and Britain but his local crags are the limestone outcrops of the Niagara escarpment.’
    • ‘On the way we stopped to dive a rock outcrop that broke the surface a few hundred metres from shore.’
    • ‘The steep contacts and elongate outcrops of the Upper Jurassic and Lower Cretaceous complexes do not, therefore, rule out gently dipping, tabular form per se.’
    • ‘On the Witwatersrand the gold-bearing rock was discovered in outcrops on the surface, but within a few years it became clear that the deposits followed reefs deep underground sloping to the south.’
    • ‘The northernmost outcrops consist of Ordovician chloritic slates, phyllitic metavolcanic rocks and slatey metapelitic rocks.’
    • ‘Thus the proto-Thames once rose in the West Midlands and carried Welsh volcanic clasts southeastwards across the Middle Jurassic outcrops into the present west-east-striking valley in south Oxfordshire.’
    • ‘The round mound incorporates natural outcrops of rock.’
    • ‘Xenoliths, which are pieces of wall rock, or xenocrysts, which are single mineral grains that originate from xenoliths, can commonly be recognized at outcrops of magmatic rocks.’
    • ‘Inselbergs are rock outcrops, several tens to several hundreds of metres high, emerging from savannas or rain forests.’
    • ‘Although there are no outcrops of Devonian extrusive volcanic rocks in NW Scotland, they can be found in southern and central Scotland and the Orkney Islands.’
    • ‘In western Thailand and eastern Myanmar, Mesozoic rocks are scattered and discontinuous, and outcrops of Palaeogene rocks are very rare.’
    hillock, mound, rise, hummock, hill, hump, knob, tor, tump, barrow, bank, ridge, dune, elevation, acclivity, eminence
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[no object]often as noun outcropping
  • Appear as an outcrop.

    • ‘Back tire slurping and bouncing wildly, I kept going, finally slithering to a halt when I saw Jeff and Joe crouched under a rock outcropping.’
    • ‘Noticing another mineral outcropping about the same size as the one his team was hiding behind, the Captain quickly made a plan.’
    • ‘Steller sea lions lumber around the rock outcropping, while others lie still, looking like so many long sandbags.’
    • ‘Without warning the monolithic stone outcropping blew into a thousand fragments of flying rock.’
    • ‘The walls of the passage were solid and rough, hewn from the granite outcropping upon which the Citadel stood.’
    • ‘The next year researchers returned to the spot and found that he had simply seen a rock outcropping that looked vertical from his position.’
    • ‘The entrance gate was expertly hidden from the main path by a rock outcropping in the slope of the mountain.’
    • ‘He spies a campfire and walks over to it; underneath a rock outcropping, two men are taking refuge from the rain.’
    • ‘I was just relaxing on a nice rock outcropping when all of a sudden, this thing opens right behind me.’
    • ‘An important hotel landmark was a large rock outcropping near the southeast corner of the building.’
    • ‘From there a path twists its way through outcropping crags and tiny lochans to the summit, perched precariously on top of its own little crag.’
    • ‘One morning I snuck up on a couple, keeping a big rock outcropping between myself and them, and when I came around the rock to find them, there was only one there.’
    • ‘At the very entrance of the cave there is a mammoth rock outcropping with a huge footprint.’
    • ‘The fact that older rocks progressively outcrop on the plateau surface to the NW suggests that the tilted surface is not a dip slope.’
    • ‘It sort of felt triumphant to be crawling up this stone outcropping after getting thrown into the river the second time.’
    • ‘Eventually it would have reached a weak spot in the terrain - a dip in the face, a rock outcropping - and broken off completely.’
    • ‘I immediately told members of my crew to stop what they were doing and to start hiking up the hill to our safety zone, a large rock outcropping.’
    • ‘A huge, bemused fiberglass giraffe looks down on the proceedings from a fake rock outcropping in the middle of the course.’
    • ‘At the camp's lowest point, a small rock outcropping serves as a storm shelter and sentry post.’
    • ‘In the rock outcropping, you notice grooves and wedge-shaped holes of varying sizes.’
    crag, cliff, tor, outcrop, outcropping
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