page_title: Volcanism of Northern Canada
section_title: Plume and rift complexes
hierarchical_section_title: Volcanism of Northern Canada / Plume and rift complexes
caption_attribution_description: English: Map of the Mackenzie dike swarm
context_page_description: Volcanism of Northern Canada has produced hundreds of volcanic areas and extensive lava formations across Northern Canada. The region's different volcano and lava types originate from different tectonic settings and types of volcanic eruptions, ranging from passive lava eruptions to violent explosive eruptions. Northern Canada has a record of very large volumes of magmatic rock called large igneous provinces. They are represented by deep-level plumbing systems consisting of giant dike swarms, sill provinces and layered intrusions.
context_section_description: Vast volumes of basaltic lava covered Northern Canada in the form of a flood basalt event 1,267 million years ago that engulfed the landscape near the Coppermine River southwest of Coronation Gulf in the Canadian Arctic. This volcanic activity built an extensive lava plateau and large igneous province with an area of 170,000 km² (65,637 sq mi) representing a volume of lavas of at least 500,000 km³ (119,956 cu mi). With an area of 170,000 km² (65,637 sq mi) and a volume of 500,000 km³ (119,956 cu mi), it is larger than the Columbia River Basalt Group in the United States and comparable in size to the Deccan Traps in west-central India, making it one of the largest flood basalt events ever to appear on the North American continent, as well as on Earth.
  This massive eruptive event was associated with the Mackenzie magmatic event, that included the coeval, layered, mafic-ultramafic Muskox intrusion and the enormous Mackenzie dike swarm that diverges from the Coppermine River Group flood basalts. The maximum thickness of the flood basalts are 4.7 km (3 mi) and consist of 150 lava flows, each 4 m (13 ft) to 100 m (328 ft) thick. These flood basalt lava flows were erupted during a single event that lasted less than five million years. Analysis of the chemical composition of the lavas gives important clues about the origin and dynamics of the flood basalt volcanism. The lowermost lavas were produced by melting in the garnet stability field below the surface at a depth of more than 90 km (56 mi) in a mantle plume environment beneath the North American lithosphere. As the mantle plume intruded rocks of the Canadian Shield, it created an upwelling zone of molten rock known as the Mackenzie hotspot. Upper lavas were partly contaminated with crustal rocks as magmas from the mantle plume passed through the lower and upper crust.
  During the Early Jurassic period 196 million years ago, the New England or Great Meteor hotspot existed in the Rankin Inlet area of southern Nunavut along the northwestern coast of Hudson Bay, producing kimberlite magmas. This marks the first appearance of the New England hotspot, as well as the oldest kimberlite eruption throughout the New England or Great Meteor hotspot track, which extends southeastwards across Canada and enters the northern Atlantic Ocean where the New England hotspot is located.
  The Sverdrup Basin Magmatic Province of northern Nunavut forms a large igneous province 95 to 92 million years old in the Canadian Arctic. Part of the larger High Arctic Large Igneous Province, it consists of two volcanic formations called the Ellesmere Island Volcanics and Strand Fiord Formation. In the Strand Fiord Formation, flood basalt lavas reach a thickness of at least 1 km (1 mi). Flood basalts of the Sverdrup Basin Magmatic Province are similar to terrestrial flood basalts associated with breakup of continents, indicating the Sverdrup Basin Magmatic Province formed as a result of rifting of the Arctic Ocean and when the large underwater Alpha Ridge was still geologically active.
  Widespread basalt volcanism occurred between 60.9 and 61.3 million years ago in the northern Labrador Sea, Davis Strait and in southern Baffin Bay on the eastern coast of Nunavut during the Paleocene period when North America and Greenland were being separated by tectonic movements. This resulted from seafloor spreading where new ocean seafloor was being created from rising magma. Scientific studies have indicated nearly 80% of the magma was erupted in one million years or less.
  The source for this volcanic activity was the Iceland plume along with its surface expression, the Iceland hotspot. This volcanic activity formed part of a large igneous province that is now sunken beneath the northern Labrador Sea. Another period of volcanic activity began in the same region about 55 million years ago during the Eocene period when the north-south trending Mid-Atlantic Ridge began to form under the northern Atlantic Ocean east of Greenland. The cause of this volcanism might be related to partial melting from movement of a transform fault s
caption: Map of the 1,267-million-year-old Mackenzie dike swarm (black lines). Dots indicate areas where flow direction was determined. Red arcuate line indicates boundary between vertical flow and horizontal flow.
exif: {}