Tag: geology

Trail of Time

as the snow thwarted our plan to hike down into the canyon, we opted to walk along the rim instead. starting near the Grand Canyon Village, the “Trail of Time” introduces visitors to the geological stages and rock formations that make up the Canyon. bronze markers embedded in the trail every meter indicate the passage of one million years of geologic time, from about 2 billion years BCE to the present and examples of various rock formations march along the side of the trail.

the oldest rocks of the Canyon lie more than 3,000 feet below the rim and aren’t visible from the rim. the Elves Chasm Gneiss is only found near the Elves Chasm and while its origins aren’t precisely known, some geologists suspect it was part of an old continental crust. the oldest rocks visible from the rim are the Vishnu basement rocks, which consist of ancient igneous and metamorphic rocks formed deep beneath the earth’s surface when island arcs (like those found off Asia today) collided with a continental mass. the Vishnu formations are primarily crystalline in structure — schist, gneiss, and granite — which differs significantly from the layers of Canyon above it, which are primarily sedimentary in composition.

the Grand Canyon Supergroup, layers of rock that have tilted, make up the next set of geological features of the Canyon. both sedimentary and volcanic in nature, the layers of the Supergroup formed over some 400 million years as continents separated and a new ocean basin formed in the new space between. precise dating for the Supergroup proves somewhat challenging; normally fossil records would aid in those determinations but these layers formed prior the diversification that resulted in hard skeletal structures of creatures.

above the Supergroup are a series of sedimentary layers collectively known as Layered Paleozoic Rocks. despite being lumped together, each layer illustrates unique characteristics that resulted in its formation — the presence of coastal sand dunes, the bottom of an ocean, etc. they show similar characteristics so some of the other National Parks found nearby and which are also part of the Colorado Plateau (Zion, Bryce, Arches, etc.) — an area of mostly flat-lying sedimentary rocks that were elevated thousands of feet above sea level some 70 million years ago (when the Rocky Mountains formed) and were then carved out by erosion. it’s easiest to see the effects of this erosion in these layers; each type of rock deteriorates in its own manner and the result is the recognizable stepped-pyramid look of the Canyon walls. shale erosion forms slopes; sandstone and limestone, cliffs; metamorphic, steep slopes as seen in the Vishnu basement rocks near the river.

the layer that forms the rim was the most recent set down. the Kaibab Formation formed in a shallow, warm sea about 270 million years ago — before dinosaurs roamed the earth. it covers a huge portion of the southwest, stretching from Northern Arizona into Utah, Nevada, and California.

the trail ends at the Yavapi Museum of Geology, originally dedicated as an observation point for studying geology in 1928. it now houses various interpretative exhibits, a topographical representation of the canyon, and binoculars to give people a chance to glimpse the river rushing  along at the base of the Canyon. it was also rather sweltering, trying overly hard to keep the bright, sunny, 40-ish weather outside.

Kolb Studios

the morning after our arrival at the Grand Canyon, we’d hoped to hike part way down the Bright Angel Trail into the canyon. unfortunately, the snow that had fallen in previous days had packed down on the shaded trail and both signs and rangers warned that crampons or some other method of “traction control” were strongly recommended.

disinclined to fork out the inflated price for Yaktrax, we opted to hike along the South Rim instead, from the Kolb Studio at the Grand Canyon Village back to the Visitor’s Center. I’m glad we made the effort to trek around the construction blocking access to the Bright Angel Trailhead, at the top of which perches the Kolb Studios.

Studio from the Bright Angel Trailhead

for those of you familiar with the Wisconsin Dells, the Kolb Brothers (Emery and Ellsworth) were to the Grand Canyon as H.H. Bennett was to the Dells, taking remarkable, breathtaking daring shots of the natural wonder of the Canyon and Colorado River. the brothers arrived at the Canyon in 1901 and 1902, one working as a bellhop in the lodge and the other hoping for work in an asbestos mine. fortunately for Emery, the mine had closed by his arrival and he stumbled upon a photography shop for sale in Williams; having previously dabbled in photography, he took the risk of the sale and began snapping shots of visitors winding their way down the Bright Angel Trail on mule trains.

initially, they operated out of a tent studio on the rim of the canyon. with the success of their business, however, allowed them to carve a shelf out of the canyon rim and construct a permanent building, which stands today as the core of the studio and museum. the studio grew through several additions including, most importantly, an auditorium in which the brothers screened the film that made them famous. though Ellsworth moved west to Los Angeles in 1924, Emery continued to run the studio and screen the film until his death in 1976, making it the longest, continually-running motion picture in the history.

the Kolb Brother’s canvas boat with cork life vest

after enjoying wide success from unique photos from the base of the Canyon and along the River, in 1911 the brothers undertook to navigate the Green and Colorado Rivers, through the Grand Canyon, eventually ending in Needles, California. the expedition took two months and they took the resulting moving picture show, the “Grand Canyon Film Show,” on tour across the country, playing to packed houses from Los Angeles to Chicago to New York City. upon returning from the screening tour, Ellsworth bought another boat and rode the spring flood from Needles to the Gulf of California, and recounted the entire adventure in the still-in-print Through the Grand Canyon from Wyoming to Mexico.

as I said, Emery stayed and worked in the studio until his death, continuing to photograph the Canyon and Rim as it became increasingly popular with tourists, changing and growing around him. proceeds from the studio and his photography helped support the entire family.

for more images of the studio, as well as the current exhibit in the studio on the Kolb Brothers, check out the National Park’s photostream.

Badlands National Park

one upside to visiting National Parks like the one in the Badlands a second time as an adult is that my memories have faded enough to allow for a wholly new experience. I have vague recollections of our last trip to the monuments and parks of western South Dakota, but nothing concrete. I remember washing dishes at our campsite, being surrounded by bison on a drive through Custer State Park, going to a cave (but nothing about the cave), lights on the surface of Rushmore (but not the carving itself, really), the heat and dryness of the Badlands.
now that I’m older, however, and have a much more comprehensive understanding of the geological (or other) forces involved in the creation of these sties, I am much more in awe. the height of the buttes and spires is obscured as you approach from the north as they’re carved out of the plains moving southward. they’re impressive and, as the name suggests, impressively inhospitable-looking. true, a fair amount of prairie grass covers the top of the butte and on the plains below — enough that someone was conducting a controlled burn of the lower prairielands as we drove through the Park.

people have inhabited the area for more than 11,000 years, the earliest of which were mammoth hunters. the Lakota moved in during the 18th century and came to dominate the region in part because of the command of horses they learned from Spaniards (it’s much easier to hunt bison on horseback …). French trappers quickly encroached on the Lakota, and they were shortly followed by soldiers (see: Custer), miners (see: Deadwood), cattle farmers and homesteaders (see: Dust Bowl).

following Wounded Knee, the Lakota were confined primarily to reservations, including the Pine Ridge Reservation which shares oversight of the Stronghold Unit of Badlands National Park. during the Second World War, the U.S. Government took possession of more than 300,000 acres of the Reservation to use the land as a gunnery range. accuracy wasn’t always great and several buildings in the town of Interior (just south of the North Unit of the park) were damaged. nearby farmers often had to take cover to save themselves from falling or misdirected ordinance. among the many informational PDFs available on the Park website is one on the history of the gunnery range that includes information on identifying and avoiding unexploded ordinance (UXO).

the site was authorized to become a National Monument in 1929 but didn’t become one until a decade later. it was redisignated a National Park in 1978 and in 1999 took over supervision of the nearby Minuteman Missile National Historical Site.

Palisades State Park

on my recent trip to South Dakota, the weather proved infinitely more agreeable for “outdoor activities” than it had been in January. still windy. very windy. but much, much warmer.

on Saturday, we set out for Palisades State Park, located just northeast of Sioux Falls in Garretson. the Split Rock Creek flows between the pink quartzite walls of the canyon, which rise between 30 and 50 feet from the surface creek. in the U.S., major quartzite formations are found in central Texas, Utah, southwest Minnesota and eastern South Dakota, and the Baraboo Hills of Wisconsin. these particular rock formations are somewhere around 1.2 billion years old and is one of the only places in the country to contain catlinite (also known as pipestone), which is used by native peoples to create peace pipes. apparently, several pipestone quarries can be found within the park (we stuck to walking along the Creek and climbing the rocks).

because of the quartzite cliffs, Palisades State Park offers excellent rock climbing opportunities (not unlike Devil’s Lake) and, despite not having any proper equipment, the three of us took the opportunity to scramble up the “Queen” spire. (the picture below is of the “King”, from where we stood atop the “Queen”.) Josie, with her much longer legs, managed to get up onto the very highest point of the spire, while Rebecca and I settled for slightly lower perches.

during the 19th century, there was a huge flour mill overlooking the bluffs and the town of Palisades bustled on the banks of the creek. in 1886, silver was discovered downstream and produced a short-lived boom (the ore turned out to be of poor quality). several years later, the railroad company built a switching yard where Garretson is now located and the town relocated. railroad officials offered free lots to business owners located in Palisades to relocate to the new town.

info from the South Dakota state park system and from the town of Garretson