Radial velocities and spatial positions of clouds in our catalog. We additionally had access to the metal absorption line sample of Ben Bekhti et al. (2008), who searched for Ca ii and Na i gas in QSO spectra obtained with UVES/VLT; see Sect. 4.1.2. Nondetections are marked with black crosses, Ca ii detections are marked with filled triangles (velocity is color-coded). No Na i absorption lines were detected. The dotted line shows the area that we used for the analysis corresponding to the map in Fig. 1.