The invention relates to a sealed, thermally-insulating tank for containing cold liquid. The sealed, thermally-insulating tank is arranged on a supporting structure (1), and comprises at least one sealing layer and at least one heat isolation layer (2, 4) arranged between the sealing layer and the supporting structure. The heat isolation layer comprises a set of first thermally insulating elements (11) arranged parallelly and forming a first layer and a set of second thermally insulating elements (10) arranged parallelly and forming a second layer arranged between the first layer and the supporting structure. Each of the thermally insulating elements (11) of the first layer comprises a casing structure filled with an insulating material essentially consisting of mineral wool or low-density polymeric foam material. Each of the thermally insulating elements (10) of the second layer comprises a block of high-density polymeric foam.