Slave Craton

The Slave craton is an Archaean craton in the north-western part of the Canadian Shield. It is found in Northwest Territories and Nunavut. It is known for having the 4.03 billion-year-old Acasta Gneiss, one of the oldest dated rocks on Earth. Though small—it covers about 300,000 square kilometers—it helps us learn about Earth's early days.

The part we can see, called the Slave Province, stretches about 680 kilometers from Gros Cap on the Great Slave Lake to Cape Barrow on the Coronation Gulf. It is made mostly of rocks formed between 2.73 and 2.63 billion years ago. These include greenstones, turbidite sequences, and plutonic rocks. Older gneiss and granitoid rocks lie below much of the area.

The Slave Craton is one of the old pieces that helped build North America. It helped form the ancient land called Laurentia. It has two main parts: the Central Slave Basement Complex in the west-central area and the Hackett River Terrane, or Eastern Slave Province, in the east. These parts are separated by a boundary that is 2.7 billion years old, running north to south across the craton.

Subdivisions

Central Slave basement complex

The Central Slave basement complex is the base under the middle and western part of the Slave Craton. Along the Acasta River, it includes very old rocks called the Acasta Gneisses. These rocks are about 4.03 billion years old, making them one of the oldest rock units known on Earth.

Scientists study the Slave Craton by looking at its shape and rocks. Some think it crashed into another land area long ago. Others believe it broke away and changed shape. Later, the area stretched out and formed a large basin. Eventually, it joined with a much bigger land area, and later connected with another area called the Rae Craton. These events helped shape the Slave Craton into what we see today, as part of Laurentia.