The Taltson magmatic zone (TMZ) is a north-trending belt of Archean to Paleoproterozoic granitic basement gneiss, amphibolite supracrustal gneissic rock and Paleoproterozoic magmatic rocks in the Canadian Shield, extending from Northern Alberta to the southwestern Northwest Territories.

[1] The TMZ basement is 3.2–3.0 Ga and the Rutledge River supracrustal gneisses 2.13–2.09 Ga years old and were intruded by magmatic rocks around 1.99–1.92 Ga.[2] The 300 km (190 mi) long exposed part of the TMZ in Northern Alberta and the Northwest Territories is bounded by the Great Slave Lake shear zone to the north and by the subsurface Snowbird Tectonic Zone to the south.

TMZ is an Andean-type continental magmatic arc and an orogenic belt between the subsurface Buffalo Head terrane on the west and the Archean Churchill Province on the east.

It is also the southern continuation of the Thelon magmatic zone, an orogenic belt between the Slave and Churchill cratons.

TMZ basement rock together with the Buffalo Head terrane can represent the earliest Paleoproterzoic magmatism, pre-dating the break-up of the Churchill Province and the Taltson–Thelon orogeny.