What is a USMC Heavy Brigade Combat Team?

Marines with 2nd Assault Amphibian Battalion fire an M2HB .50-caliber machine gun in a live fire training event during a Heavy Brigade Combat Team qualification course aboard Camp Lejeune, N.C., June 19, 2015. During the live fire event, the Marines aimed and shot at moving targets to simulate enemy movement. (U.S. Marine Corps photo by Lance Cpl. Chris Garcia/Released)

Hey!  Does anyone know what a USMC Heavy Brigade Combat Team look like?  Any idea of its manning and equipment?  Is this new, just something I hadn't heard of or simply a captioning mistake?