fendue

CONT: Lorsque le gîte est à profondeur modérée, on l'atteint à partir de la surface par une galerie inclinée, ou «fendue», dont la pente admissible est limitée à environ 18° [...]
OBS: Lorsque la pente est forte, c'est un puits incliné.

CONT: Three methods, drift, slope, and shaft (or various combinations thereof), are used to gain access to coal located too deep underground for surface mining. ... A slope is an inclined opening driven to work a seam with a downward inclination, or to reach from the surface to a seam or between seams.
OBS: When not open at one end to the surface, it is known as an inside slope.