My buddy Al and I were like teenagers with a new car, though the calendar said we were well into our 70s. It was a sunny September day; two ultra-lightweight kevlar canoes shipped from the Adirondacks of New York were strapped atop my Subaru; and we were zipping up the curves of the deep Feather River Canyon in the Sierra foothills east of Chico. An hour ahead, lakes galore awaited us in the aptly-named Lakes Basin region of the northern Sierra Nevada between Graeagle and Lake Tahoe.
We’d kayaked there last summer, hitting many of the lakes with launch sites accessible by car. But this trip we determined to paddle on Big Bear Lake, a half mile from any road. That meant what in the Adirondacks was called “a carry” of our canoe and gear. Impossible with our 42-pound kayaks from last year. These kevlar vessels today, though, only weighed 12 pounds. But they were 10 feet long, awkward to heft, and the trail was rocky, windy, and choked with tree roots. I’d devised—well, jury-rigged is more descriptive—a carrying rig to mesh me and my canoe on the trail. Would it work?
It’s a strange drive, up the Feather River Canyon. At the start of the drive, coming out of the Central Valley, the rock comprising the canyon walls is granite, beautiful granite much as you see in Yosemite Valley today. But halfway up the canyon, something weird happens. Our beautiful granite disappears, and the canyon walls become a combination of greyish and bluish rocks of entirely different texture, looking very worn and almost “tortured.” What the heck was this all about?
We arrived at our Gold Lake Lodge in the early afternoon, stashed our gear in the rented tent-cabin, and headed for a quick paddle on the car-accessible Lower Sardine Lake. Once on the water, we headed straight across the lake, where the massive Sierra Buttes loomed 8,587 feet tall. Again: these buttes weren’t granite, but dark, ugly rocks, a telltale reddish 60 degree slant to its main crag, as my photo in the far-right column shows.
And therein lies a tale. For this was not the granitic “Range of Light” celebrated by John Muir. The Sierra Nevada’s central and southern range is granite and relatively recent. But the range’s northern peaks here are far older, far more stark and forbidding—and composed of twisted, tortured metamorphic rock. Oh, there’s granite here, but it’s many hundreds of feet below us, diving deeper to the north and into Oregon. It’s the granite left behind, the granite covered by an ancient Sierra Nevada that in the range to the south of us was uplifted and eroded away to reveal the underlying granite—but not here. Here in the north the ancient, original Sierra Nevada still reigns, still covering the granitic blocks lying beneath it. And its appearance amply attests a violent history.
To understand how this came about, let’s look at the evolution of the Sierra Nevada range, before getting to “the carry” into Big Bear Lake. This tale has a prelude and three acts. It all began (Prelude!) 450 million years ago in the Paleozoic. North America’s western shore was approximately where Nevada is now; what would become “California” didn’t exist yet. Instead, sediment from the young continent (sand, silt, mud, a few dinosaur skeletons) flowed into the offshore waters of the continental shelf and settled on the seafloor there. Over the ages, the calcium-rich skeletons of marine creatures were added to the mix, along with lava from undersea and island volcanoes. This sedimentary mixture compacted into a concrete-like consistency over the ensuing 200 million years.
Act One commences toward the end of the Paleozoic, 230 million years ago, as the North American crustal plate began to drift west, colliding with the Pacific crustal plate which was moving east. Something had to give, so the sedimentary ocean floor mixture on the Pacific plate underwent subduction, diving deep under the North American plate toward the earth’s core throughout the early Mesozoic. As it descended, the mixture melted, underwent tremendous change, and cooled finally into a long string of granitic blocks called plutons, running north-south deep under the continental coastline. (Some of the molten mixture made its way to the surface and erupted, adding Mesozoic lava to the surface of the continent’s edge.) These granitic plutons, buried deep under the surface, would over the ages rise to become today’s southern and central Sierra Nevada—but that’s getting ahead of the story.
Act Two begins in the mid-Mesozoic, just after the granitic plutons are being formed deep under the surface. About 150 million years ago, the speed of the North American and the Pacific plates’ drift increases, sending the plates crashing more violently into each other. Rather than subducting neatly under and diving deep, as had happened earlier, the sedimentary and volcanic rocks of the ocean floor, as well as some of the Pacific crust itself, get brutally jammed against North America, buckling and folding and heating as they undergo extreme pressure. They metamorphose, changing into new rocks. This material piles up some 15,000 high against the edge of the continent, forming a new extension of the North American continent: the original Sierra Nevada range, about as high as the present one, and like the present one tilted, high in the east, about a 60 degree slant (which Al and I could see in a great slab near the top of the Sierra Buttes above Lower Sardine Lake).
This Mesozoic Sierra Nevada range has nothing to do with granite (hidden far underground at this time, remember), but is composed of a mixture of rocks that have undergone metamorphosis: Paleozoic and Mesozoic ocean-floor sediments, volcanic lava, and original crustal material from the seafloor itself . The Paleozoic sedimentary rocks shale, mudstone, siltstone, and sandstone, for example, metamorphose into slate, phyllite, chert, and hornfels. Limestone becomes marble. Volcanic material becomes schist and greywacke. The crustal seafloor in the mixture metamorphoses into serpentine and similar rocks of grey-green-bluish hue—what we had seen forming the canyon walls an hour into our drive up.
To finish Act Two: throughout the rest of the Mesozoic, this original, metamorphic Sierra Nevada erodes—we’re talking tens of millions of years, remember. By the end of the Mesozoic, as the Cenozoic begins, the original Sierra Nevada is merely a long, north-south stretch of hills. Where did that 15,000 foot range go to? It eroded west into a great trough, originally under water, where the broken-up, mineral-rich metamorphic rocks were deposited in a thick layer of wonderful soil: today’s Central Valley of California, an agricultural treasure-house. This erosion was more pronounced in the southern and central parts of the original Sierra Nevada, where in many places the underlying granite plutons were exposed. But in the northern part of the original range, the metamorphic rocks of the Paleozoic and Mesozoic still amply covered the granite
A long period of relative quiescence (by geologic reckoning) now ensues as the Cenozoic dawns 65 million years ago. The fault lines running parallel along the eastern edge of the granitic block rest—uneasily, yes, but it is not until well into the Cenozoic that the great granite plutons are shaken.
Act Three begins relatively recently, only 10 million years ago, and strikes first in the northern region, where fault lines shift, lifting both the underlying granite plutons and the covering metamorphic rocks of the Paleozoic and Mesozoic. But the really violent earthquakes begin 7 million years later, and strike in the central and southern reaches of the range. Major shifting occurs along what geologists term en echelon (staggered, parallel) faults along the eastern edge of the old range here. As the earth moves, the eastern edge of the granite plutons rise dramatically, and a new Sierra Nevada range is born in these southern regions, the Sierra Nevada of today. This uprising of a new Sierra Nevada intensified 700,000 years ago, and continues into historic times. In the 1872 the Owens Valley earthquake, the eastern edge of the new Sierra Nevada rose 13 feet in a couple of minutes, with a lateral displacement of 20 feet.
(This is the quake experienced by John Muir in Yosemite Valley not far to the north, who rushed out of his cabin shouting “A noble earthquake! A noble earthquake!” and calmed his terrified neighbors by assuring them “Cheer up; Mother Earth is only trotting us on her knee to amuse us and make us good!” Muir promptly celebrated by crazily bounding down the slope of still-warm rocks newly fallen from the valley sides.)
Geologists calculate that this new, granitic Sierra Nevada is in fact still rising, at an average of 15 inches every century. Since the highest southern-most peak, Mt. Whitney, is 14,495 feet high (or so, depending on the method of measurement), in only half a millennium this latest edition of the Sierra Nevada will have topped the original range’s 15,000 feet. Something to look forward to!
There are still remnants of the original Sierra Nevada in the central and southern stronghold of the new granitic range. In a few scattered, isolated locations, the old range’s dark, tortured rocks sit perched atop the more common granitic rocks, a grim reminder of ancient times. These remnants from long ago are called, appropriately, “roof pendants.” Standing in Tuolumne Meadows in Yosemite National Park and gazing east, the peak of Mt. Dana is noticeably—well, different, than everything round it: a roof pendant from the Mesozoic. Twenty miles to the south, the top of Mt. Ritter, where Muir momentarily lost his nerve and nearly fell to his death in 1872, is another of these roof pendants.
(This account of the evolution of the two Sierra Nevada ranges is drawn from Stephen Whitney’s The Sierra Nevada, part of the Sierra Club Books’ series of naturalist guides. Warning: geologists are still learning about all this, and my simplified, dramatized version of Whitney’s account will be amended and improved as research—and disputes!—continue.)
But that’s all to the south of Al and I as we paddle across Lower Sardine Lake, the rugged, metamorphosed rocks of the Sierra Buttes rising majestically 8,587 feet above us. It’s a grand paddle, and the gurgling of water cascading down from Upper Sardine Lake a mile above us to the east persuades us to hike up to it later.
The next day we’re off right after breakfast (the food at Gold Lake Lodge, provided by owner and chef Rob Remlinger, is superb), driving to the Long Lake trailhead, canoes strapped on top. These lightweight canoes, “Hornbecks” crafted of kevlar or carbon fiber by Peter Hornbeck in the Adirondack region of New York, are inspired by the 10.5-pound canoe in which George Washington Sears traversed the lakes of New York’s Adirondack wilderness the summer of 1883, an adventure covering 266 miles. Sears, at 5 foot 3 and 110 pounds, was a born adventurer, having shipped out on a whaler to the South Pacific from Cape Cod when he was 19 in 1841, the same year as Herman Melville had. He had made 2 trips to the Amazon subsequently, but at age 62 and suffering from “consumption”, decided to stay closer to his Pennsylvania home for this trip.
The Scot James McGregor had popularized solo canoeing trips with his 1866 account A Thousand Miles in the Rob Roy Canoe on Rivers and Lakes of Europe. Sears would face numerous “carries” between the Adirondack lakes on his six-week jaunt, and wanted a craft considerably lighter than McGregor’s 80-pound canoe. He turned to the famous New England canoe builder J. Henry Rushton, who made him several versions, each smaller than the last. Finally Sears had his canoe, which he christened the Sairy Gamp, after Dickens’ tipsy Cockney midwife in Martin Chuzzlewit. (A spell working in a factory while still a child had made Sears interested in Dickens.) “I was trying to find out how light a canoe it would take to drown a man,” Sears wryly commented. Yet he was dunked only once in his 266 miles.
My 10-foot kevlar “Classic” Hornbeck weighs 12.5 pounds, 2 pounds more than the Sairy Gamp (now owned by the Smithsonian, and exhibited at the Adirondack Museum at Blue Mountain Lake); Al’s 12-foot “Blackjack New Tricks” Hornbeck (of carbon fiber) is 13 pounds.
The Long Lake Trail is a 3-mile loop passing a series of gorgeous montane lakes (going counter-clockwise): Long, Silver, Cub, Little Bear, and Big Bear. We unload the canoes, stash the straps and ties in the Subaru, and head clockwise up the “end” of the trail, going directly to Big Bear Lake half a mile away. I’ve rigged up a cross-chest carry, scavenging a shoulder strap from an old laptop bag, the cut-off (and hence short) remains of a Thule roof-rack strap that had become frayed, and a climbing sling. I put the shoulder strap on my left shoulder, lift my canoe hip-high on my right side, attach the shoulder strap’s front end by a carabiner to the Thule strap wrapped obliquely around the front of my canoe, and attached its back end by a carabiner to the climbing strap tightly knotted to the cross-gunnel behind my canoe’s seat—as illustrated in the photo at the beginning of this blog.
Though I had tried this rigging in my backyard, I hadn’t done any trail-walking, rock-dodging, and tree-avoiding with it. To my relief, it worked fine. Carrying 12.5 pounds beside me in this sort of cross-chest arrangement proved to be—well, like a walk in a park. No particular problem, so long as you watched the numerous rocks and tree-roots over which you traversed, and tried to soften the inevitable banging of canoe against pines pressing close beside the trail.
Al, busy with the late harvests of his large summer garden and prepping his winter garden, hadn’t had the opportunity to mess with fancy rigs, so he simply hoisted the darn canoe atop his shoulders and set off. Though perhaps not as graceful as my carry, his certainly got him and canoe to the same destination, with plenty of energy to spare. (He has since devised a cool rig that rests the Hornbeck on the top of an exterior frame Kelty backpack, nicely balanced above his head.) We found a shallow, gravel-bottom entry point, set the Hornbecks on the water, climbed in our crafts safely if not elegantly, and dipped our paddles.
Heaven: a pristine montane lake, picturesque metamorphic boulders around and rising from it in islands, hillsides of Jeffrey Pine and Hemlock ringing the lake, elevation-dwarfed White Alder along the shore, the whole under a white-cloud-studded sky of the brilliant shade of blue only found in the mountains, “unknown to valley-dwellers” (as the also-tipsy Li Po put it, a thousand years ago).
Next summer: Long Lake, a mere mile “carry”, George Washington Sears and the Sairy Gamp dancing in our heads.
Living and Writing in the Natural World
"The Carry" into the other--older--Sierra Nevada
October 8, 2018
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