The Global survey of open clusters in the Milky Way I: 3D map of absorbing matter

Basing on data on open clusters from MWSC (Milky Way Star Clusters) survey we construct a 3D map of a distribution of interstellar absorbing matter as indicated by aV = AV /d in the wide Solar Neighbourhood of the Galactic disk with a size of 10×10×4 kpc. The map shows at lower extinctions aV . 0.9m /kpc a uniform disc with a thickness of 0.4 - 0.8 kpc. At aV > 0.9 m /kpc interstellar medium exhibits inhomogeneity with typical size of the enhanced density regions below 1 kpc. Some dense clouds are found at considerable heights of |Z| up to 0.6 kpc.