Laurasia was a super continent that most recently existed as a part
of the split of the Pangaea super continent in the late Mesozoic era. It
included most of the landmasses which make up today's continents of the northern
hemisphere, chiefly Laurentia (the name given to the North American carton), Baltic,
Siberia, Kazakhstan,
and the North China and East China cartons. Although
Laurasia is known as a Mesozoic phenomenon, today it is believed that the same
continents that formed the later Laurasia also existed as a coherent super continent after the breakup of Rodina around 1 billion years ago. To
avoid confusion with the Mesozoic continent, this is referred to as Proto-Laurasia.
It is believed that Laurasia did not break up again before it recombined with
the southern continents to form the late Precambrian super continent of Pannotia,
which remained until the early Cambrian.