表面出现小孔洞或小规模凹陷，是由历时的风化(作用)、侵蚀或其他过程所导致。——AAT-台湾  @zh

pitting：the formation of pits or small depressions on a surface, as on the skin by smallpox, on metal by corrosion, etc.; (also) a pit, a small; a series or expanse of small hollows or depressions.——Oxford English Dictionary  @zh

点蚀  @zh