Školjkanje je lom tla po površini u obliku školjke i to je mehanizam na osnovu koga nastaju odroni/klizišta većih ili manjih razmera.

http://www.urbel.com/documents/planovi/4817(sl l 20-07).pdf
Građevinski iskopi u okviru ovog rejona mogu se izvoditi bez zaštite do dubine od 1,5-2 m (pri čemu iskope treba izvoditi u kraćem vremenskom intervalu), a dublje iskope treba štititi odgovarajućom zaštitom ili iskop izvoditi u kampadama zbog mogućeg školjkanja u sedimentima koji izgrađuju telo fosilnog klizišta.

http://books.google.com/books?id=vv2-HRTduYQC&pg=PA1464&lpg=...
Causes of landslides are varied. The most frequent case is when drainage networks of local streams are cut into Neogene sediments, which is much faster than intensity of surface erosion. By disturbing tha natural balance ratio due to the cutting of underlying stratum, at initial stage there is a terrain reaction and the appearance of conchoidal fractures and break-offs, and afterwards followed by sliding of earth materials as well as by successive expansion of instability process towards upper slope parts till the establishment of illusive balance.

Evo primera školjkanja u steni:
http://blogs.agu.org/mountainbeltway/2010/11/02/thats-what-y...
Obsidian bearing well-developed conchoidal (clam-shell-shaped) fracture with concentric ribs, as displayed at the recent U.S. Science and Engineering Festival on the National Mall by a local gem/fossil/mineral club.

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Note added at 1 day19 mins (2010-11-10 11:38:11 GMT)
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http://www.thefreedictionary.com/conchoidal
Of, relating to, or being a surface characterized by smooth, shell-like convexities and concavities, as on fractured obsidian.

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Note added at 1 day25 mins (2010-11-10 11:43:27 GMT)
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U vašem kontekstu naravno treba napisati: appearance of conchoidal fractures and break-offs