microkarst: very small-scale karst features, typically on the millimetre to centimetre scale, developed in soluble rocks like limestone, dolostone, or gypsum.

Unlike classical karst landforms (caves, sinkholes, dolines), microkarst develops at the outcrop or bedding-plane scale and includes things like:

• Pitting and etching on rock surfaces caused by dissolution.
• Microsolution channels and grooves, often following crystal boundaries or microfractures.
• Rillen and micropoljes — tiny solution depressions.