Level Mountain is a large volcanic complex in the Northern Interior of British Columbia, Canada. It is located 50 kilometres (31 miles) north-northwest of Telegraph Creek and 60 km (37 mi) west of Dease Lake on the Nahlin Plateau. With a maximum elevation of 2,164 metres (7,100 feet), it is the second-highest of four large complexes in an extensive north–south trending volcanic region. Much of the mountain is gently sloping; when measured from its base, Level Mountain is about 1,100 m (3,600 ft) tall, slightly taller than its neighbour to the northwest, Heart Peaks. The lower, broader half of Level Mountain consists of a shield-like structure whereas its upper half has a more steep, jagged profile. Its broad summit is dominated by the Level Mountain Range, a small mountain range with prominent peaks cut by deep valleys. These valleys serve as a radial drainage for several small streams that flow from the mountain. Meszah Peak is the only named peak in the Level Mountain Range. The mountain began forming about 15 million years ago and has experienced volcanism up until geologically recent times. There have been four stages of activity throughout the long volcanic history of Level Mountain. The first stage commenced 14.9 million years ago with the eruption of voluminous lava flows; these created a large shield volcano. The second stage began 7.1 million years ago to form a structurally complicated stratovolcano located centrally atop the shield. A series of lava domes was established during the third stage, which began 4.5 million years ago. This was followed by the fourth and final stage with the eruption of lava flows and small volcanic cones in the last 2.5 million years. A wide range of rock types were produced during these stages, namely ankaramites, alkali basalts, trachybasalts, mugearites, hawaiites, phonolites, trachytes and rhyolites. Alkali basalts and ankaramites are the most voluminous and form most of Level Mountain. The remaining rock types are less extensive and are largely restricted to the central region of the volcanic complex. Several types of volcanic eruptions produced these rocks. Level Mountain lies in one of many ecoregions throughout British Columbia. It can be ecologically divided into three sections: lodgepole pine and white spruce forests at its base, bog birch and subalpine fir forests on its flanks, and an alpine climate at its summit. The extent and flatness of the alpine on Level Mountain have produced many Arctic affinities that are particularly noticeable in the local biota. Several animal species thrive in the area of Level Mountain, caribou being the most abundant. A trading post was established at Level Mountain in the 1890s, followed by geological studies of the mountain from the 1920s onwards. This remote area of Cassiar Land District has a relatively dry environment compared to the Coast Mountains in the west. Due to its remoteness, Level Mountain can only be accessed by air or by trekking great distances on foot. The closest communities are more than 30 km (19 mi) away from the mountain.
Geography and geomorphology
Structure Level Mountain has a volume of 860 km3 (210 mi3) and an area of 1,800 km2 (690 mi2), although at least one estimate of its areal extent is as much as 3,000 km2 (1,200 mi2). Because of its great extent Level Mountain can be seen from outer space. This, coupled with snow and elevation, helps define the geology of the region. Level Mountain dominates the Nahlin Plateau, a subdivision of the larger Stikine Plateau. Level Mountain consists of two principal components: a voluminous basal shield volcano and an overlying eroded stratovolcano. The lower, but more extensive basal shield volcano rises from an elevation of 900 to 1,400 m (3,000 to 4,600 ft) above the surrounding forested lowlands much like an inverted dishware plate. It is 70 km (43 mi) long and 45 km (28 mi) wide with a net altitudinal reach of only 750 m (2,460 ft). This part of the mountain forms a broad, oval-shaped, north–south trending lava plateau on which local streams flow. The south and west sides of the plateau are marked by a well-defined, but dissected escarpment. In contrast, the north and east plateau boundaries are less clear. V-shaped stream canyons occur along the lava plateau margin, exposing a section of Tertiary basalts along the Grand Canyon of the Stikine. From an elevation of 1,400 m (4,600 ft) onwards the overlying stratovolcano is dominant. Ridges and peaks prevail at an elevation of 1,520 m (4,990 ft) and form the Level Mountain Range. These rise more steeply to 1,980 m (6,500 ft), eventually reaching the highest point of 2,164 m (7,100 ft) at Meszah Peak. Therefore, when viewed from a distance, Level Mountain appears unusually flat except for a number of black peaks on its summit which have the appearance of enormous volcanic cones.
Biogeography Level Mountain is in the Stikine Plateau Ecosection, an area of partially dissected upland characterized by rounded ridges and wide valleys. It contains several small lakes, marshes, muskegs and streams, the latter of which drain into the Stikine, Taku and Liard watersheds. Boreal black and white spruce are present in valley bottoms, black spruce being commonly found around wetlands such as muskegs. Level Mountain has been described as the most impressive feature in the Stikine Plateau Ecosection; it is one of the few locations in this ecosection where alpine vegetation can be found. Although alpine vegetation of the Stikine Plateau Ecosection can be lush and grass-rich above the tree line, wetlands and muskegs are the dominant ecosystems on Level Mountain. The Stikine Plateau Ecosection is one of seven ecosections composing the Boreal Mountains and Plateaus Ecoregion, a large ecological region of northwestern British Columbia encompassing high plateaus and rugged mountains with intervening lowlands. Boreal forests of black and white spruce occur in the lowlands and valley bottoms of this ecoregion whereas birch, spruce and willow form forests on the mid-slopes. Extensive alpine altai fescue covers the upper slopes, but barren rock is abundant at higher elevations. A cold, dry boreal mountain climate characterizes this ecoregion.
Plants
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