Autumn Aspen and the Markagunt Plateau Volcanic Field

October 03, 2016

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October 2016 Viewer's ChoicePhotographer: Ray Boren
Summary Author: Ray Boren

The dark and blocky basalt volcanic flows capping portions of southwestern Utah’s high Markagunt Plateau are impressive in every season, but when the leaves of the region’s aspen trees turn a shimmering yellow in autumn, the contrasts in the landscape are both awesome and beautiful.

The Markagunt — meaning "highland of trees" in the Paiute language — is an 800 square mile (2,100 square km) plateau on the western fringe of the greater Colorado Plateau Province of Utah, Arizona, Colorado and New Mexico. Cedar Breaks National Monument, a spectacularly eroded cliff amphitheater above Cedar City, Utah, is on the Markagunt’s west edge, with rim elevations topping 10,000 ft (3,048 m). Brian Head, a nearby peak and the summit of a ski resort of that name, is the Markagunt’s high point, at 11,307 ft (3,446 m). East of Cedar Breaks in the plateau’s midsection is a dormant belt of volcanic fissures, fields and cinder cones, active beginning about 5.3 million years ago, according to the U.S. Geological Survey — and continuing to burble as recently as the year 1050 A.D., according to dendrochronological tree-ring studies.

In fact, the vast and jumbled basalt fields born of those flowing eruptions are so young that they remain rather sparsely vegetated. Quaking aspen (Populous tremuloides) and some pines and shrubs have, however, found footholds where soil has accumulated among tumbled boulders and on the lava flow frontiers. In autumn, shorter days and cooler temperatures spur the breakdown of chlorophyll in the aspen trees’ quivering leaves. Summer greens give way to yellows, and sometimes reds and oranges. And the pairing of bright aspen and brooding, black basalt is indeed something to see, as illustrated by these photos, taken on September 17, 2016.

Photo Details: Top - Camera Model: NIKON D3200; Lens: Tokina AT-X 124 AF PRO DX II (AF 12-24mm f/4); Focal Length: 12mm (35mm equivalent: 18mm); Aperture: ƒ/10.0; Exposure Time: 0.0031 s (1/320); ISO equiv:400. Bottom - same except: Focal Length: 19mm (35mm equivalent: 28mm); Aperture: ƒ/6.3; Exposure Time: 0.0063 s (1/160); ISO equiv: 100.