A tale of two men and geology on the roof of the world
by Miles Traer
Part I – Onto the Mountain
I’m sitting in a warm room wearing flannel pajamas with a hot meal in my belly when the title card on the movie fades and the 90-year-old film begins to flicker. The circular aperture is neatly divided along a diagonal line: the top featureless white, the bottom textured rough and grey – both ghostly. Darker striations run across the grey, further broken by white snow that looks like a child’s finger painting flecked with white and black dots. It’s only after several seconds that I notice that a few flecks of black are moving along the border between the white and grey, moving higher along the diagonal. Another title card appears and informs me that these tiny flecks are men, and the striated and speckled grey is Mount Everest as she appeared in 1924, on the eve of one of the most famous disappearances in mountaineering history.
Ever since the first westerners set foot on Mount Everest nearly a century ago, people have tried for her summit. They battled fierce winds, freezing temperatures, and elevations that seem to steal the oxygen from the lungs. They climbed across glaciers, they kicked steps into the snow and ice, and, of course, they scampered across the exposed rocks. From Everest’s basecamp in 1924, photographer John Noel wrote, “In these lofty solitudes we may feel in touch with the naked elements of which the world has built itself.” Samantha Larson, the youngest non-Nepalese woman to ever summit Everest in 2007, expanded on this:
“Being out in the naked elements is such a huge part of the experience that it’d be hard to imagine it not being a big part of the draw for any mountaineer. There’s something about cutting out the noise of everyday life and simplifying existence down to the pursuit of one goal that fills an innate human need for purpose. And something about doing that in a way that’s so in tune with what the Earth throws at you makes that pursuit feel really pure.”
In 1924, two climbers named George Mallory and Andrew Irvine found themselves confronted with these naked elements – what I will call the geologic forces of the mountain. Everest’s geologic history reaches back over 500 million years and captures fantastic and terrifying powers that shaped not just the mountain, but the Earth. While they might not have known it, as Mallory and Irvine climbed ever higher on the mountain and into the clouds, they were walking into geologic history.
Part II – A Prodigious White Fang
In the spring of 1921, George Mallory sat down to rest atop worn and broken pieces of rock exposed to the sun and gazed out towards the horizon, broken by the jagged peaks of the Himalaya. Born in England, he was accustomed to the high mountains of the Alps, but the Himalaya seemed impressively elevated, even to his well-trained mountaineer’s eye. From his perch on the raised moraine, Mallory’s brow furrowed as his eyes focused on a single mountain that stood above the rest, with a white plume of snow trailing from its summit, caught by the harsh winds of the jet stream. Mallory, never shy to liven his descriptions with lofty prose, described this mountain as “a prodigious white fang excrescent from the jaw of the world.” In many ways, this white fang of a mountain would define his life. It certainly came to define his death. From this first sighting in 1921, Mallory’s single mission was to be the first to climb Mount Everest.
Three years later, Mallory returned to the mountain with the 1924 British Mount Everest Expedition. Mallory’s climbing partner was a young engineering student who had little experience climbing mountains. Andrew Irvine, whom everyone called “Sandy,” had become fast friends with Mallory during the voyage to basecamp. Mallory continuously asserted that Irvine was a fine young mountaineer, fully capable of such a climb. But many historians, and indeed some others on the expedition, thought that Irvine’s greatest attribute was his knowledge of the newly designed oxygen apparatus that some thought was the key to reach the summit.
At 35 years old, Mallory’s face still retained a boyish quality, with thin lips, a narrow nose flanked by high cheekbones, and ears that stuck noticeably outwards. At 21 years old, Irvine seemed always to smile beneath his mop of blonde hair. With his skinny frame, Mallory did not look the part of the mountaineer while Irvine cut an imposing figure with broad shoulders and powerful legs. The gregarious Mallory would often joke with his climbing companions while the shy Irvine tended to listen. Balanced with wisdom and innocence, skill and power, the two men made an ideal summit team.
Twelve men, including Mallory and Irvine, composed the expedition supported by a large number of invaluable porters – men who hauled gear up the mountain and without whom the entire endeavor was impossible. Of the many men on the mountain, I will focus on four: Edward “Teddy” Norton (the expedition’s leader), Howard Somervell (who, along with Norton, composed the primary summit team), and documentarian John Noel (who hauled telescopic cameras to Everest to photograph and film the expedition). The final piece of the climbing puzzle was Noel E. Odell. Odell served to assist the summit teams along the climb, but was on the expedition to explore the summit as Mallory and Norton could not: Odell was a geologist.
The planned route to the summit began at the East Rongbuk Glacier, a sea of flowing ice like 40-foot shark’s teeth that creaked and moaned as they slid down-slope. From the glacier, the teams would climb a dauntingly steep slope up to a saddle between Everest and a neighboring mountain. This saddle, called the North Col, would serve as the staging area for the final assault on the summit. From the North Col, the teams would follow a narrow rib of rock along the north face until they reached the Northeast Ridge, which they would follow to the summit. The planned route was to take only 18 days, but it did not allow for bad weather. The snows the team faced in the spring of 1924 were the worst in decades.
When the team reached the Rongbuk Glacier on May 9th, snow squalls and freezing temperatures immediately hit them. Exposed to the high elevations and terrible weather, nearly everyone on the expedition began to fall ill. Pounding headaches were the norm, some bad enough to induce vomiting that only worsened their dehydration. Frostbite began to set in as climbers established Camps II and III higher up on the glacier. And all the while, the snow continued to fall and accumulate on the slopes above the North Col.
The weather finally broke on May 17th. The inexperienced Irvine set out with Somervell and a small team of other climbers to establish Camp IV on the North Col. To reach the Col, Irvine climbed a steep wall of ice and snow that stretched 1,000 feet above the glacier. He used ropes and boards to fashion a makeshift ladder to surmount sections otherwise too steep to climb with the heavy packs on their backs. Irvine and Somervell’s team established Camp IV before retreating back to Camp III exhausted from the effort. Four porters remained at Camp IV. Two days later, the snow began to fall again and the temperature plummeted to -24° F (-31° C). At Camp III, Irvine could only watch as the mist began to envelop the four porters at Camp IV. When the blizzard hit, Irvine looked to Mallory and Norton.
The story of the awe-inspiring forces that built Everest, what cameraman and mountaineer John Noel described as “the naked elements of which the world has built itself,” is in many ways the story of the scientists and explorers who unraveled the twists and turns as they looked back through geologic time. Our story begins only 12 years before Mallory, Irvine, and geologist Noel Odell reached Everest, and we must travel to a different continent half a world away: Antarctica. In this remote part of the world at the dawn of the 20th century, another famous and ill-fated explorer collected a series of rocks that would fundamentally change the way we viewed the Earth.
In 1912, Robert Falcon Scott and his team of Antarctic explorers raced to become the first to reach the South Pole. By this time, the concept of continental drift was already established, but not universally accepted. During his journey, Scott collected various rocks that contained fossil remnants of long dead plants and animals. While Scott and his explorers tragically died during their return journey from the pole, his samples made it back to Britain. One of these samples, a fossil of a plant called Glossopteris, catapulted continental drift to the forefront of geology.
Its leaves were wide and round and looked like tongues pressed into the rock. Glossopteris fossils showed up in South America, Africa, Australia, Antarctica, and in the Himalayan foothills in India. The question that geologists asked was, how did this plant manage to spread so widely across the Earth over such vast oceans? The (then) preposterous solution was that at some point in Earth’s past, all of these continents had joined together in a single landmass – a supercontinent known as Gondwana1. This was strong evidence of continental drift and the theory of plate tectonics that now defines so much of geology. By 1924, it was enough to suggest that India had not always been a part of Asia, and its movement might have had something to do with the creation of the tallest mountains on Earth.
The evidence of plate motion continued near Everest basecamp where Noel Odell entered the valley carved by the East Rongbuk Glacier. The first rock-type he noticed was gneiss – a metamorphic rock, transformed from either granite or sedimentary rocks under high temperatures and pressures, like those found as one continent collides with another. In 1924, most geologists theorized that the Everest gneiss formed within the earth resulting from metamorphism of igneous rocks. But Odell challenged this theory, writing in his report on the geology of Everest, “my investigations, brief and incomplete as they were, have brought me more and more to the view that this particular series of banded biotite gneisses represents in actuality a highly metamorphosed series of sediments.” While Odell didn’t know it at the time, the collision pushed the sediments deep inside the Earth, to a depth of 19-37 miles (30-60 km): over 5 times the height of Everest. Here, the ancient sediments cooked until tectonic forces pushed the rocks back to the surface.
The second rock type that caught Odell’s attention was granite. He noticed it between the layers of gneiss and documented the ancient heat that partially melted the surrounding rock. Years after Noel Odell left Everest, scientists developed the techniques to accurately determine the age of the rocks – only 20-24 million years old. To a geologist, this is relatively young. And more importantly, it provided the youngest possible age for the collision of India with Asia, which we now know began around 50 million years ago.
The theory of plate tectonics would not be widely accepted until the late-1960s. When Noel Odell collected samples of the granite and gneiss in the Rongbuk Valley in 1924, he knew that powers beyond imagination were acting in the region. He noted that, “Many observers have of course seen ample signs of special elevator forces… to give such prominence to this great sector of the Earth’s crust.” He continued by postulating that Everest’s tremendous elevation “must be largely due to vertical uplift in the past that may be continuing at the present time.” While the theory of plate tectonics wouldn’t be formally adopted for another four decades, Odell’s and others’ observations strongly hinted at a deeper understanding of the processes that created the tallest mountain on Earth.
Part III – So Utterly Far Away
As the blizzard worsened, Norton ordered everyone off the mountain except Mallory and Somervell. The three men mounted a rescue of the four porters stranded at Camp IV. Mallory certainly recognized the immediate danger posed by the accumulating snow on the 1,000-foot face. In 1922, at this exact spot, an avalanche had swept away 7 Sherpas who were climbing with Mallory late in the season. The tragedy had hit Mallory hard, and he spoke of it often with his wife, Ruth. As Mallory, Norton, and Somervell grabbed their ropes and ice axes and prepared to climb, Mallory knew he and his companions were risking the unstable snow, steep slope, and fierce winds. Up at Camp IV, the porters waited out the frozen night listening to what they called “the distinctive howl of the watchdogs guarding the mountain.” At Camp III, Mallory wrote, “Never, I confess has a task appeared to my mind so utterly far away and unlikely to be accomplished.”
Climbing in fits and starts, Mallory, Norton, and Somervell made their way up the face. As they approached Camp IV, they used the rope tied around each other as a handrail that the trapped porters could use to ease the descent. The climb was slow through the waist deep snow, and it wasn’t until late in the afternoon that they neared Camp IV. As Somervell approached the camp, the rope around his waist came taught. He couldn’t reach the tents. Somervell, Mallory, and Norton yelled to the porters and told them they would have to slide down just a few feet of snow to reach the rope. As the porters tried to descend, two lost their footing and began to slide towards the ice cliffs. In a fortunate twist, the buildup of fresh snow arrested the slide and they were able to scamper back to the rope. The team of 7 men carefully descended the remainder of the face. At the bottom, geologist Noel Odell and photographer John Noel met the team with thermoses of hot soup. They had made it down. But the high camps still needed to be established and time was running short.
Experienced mountain climbers point out that Everest is not a technically difficult mountain to climb – the challenge is the elevation. During most plate collisions, denser oceanic crust slides beneath the less dense, and hence more buoyant, continental crust. But when India collided with Asia, continental crust met continental crust. However, the Tethys Ocean once separated these two landmasses, and the denser oceanic plate helped drag the Indian continent under Asia. As the plate subducted for 10-100s of miles, it began to melt. The melt, being less dense than the surrounding rock, rose up under the forming mountains. For simplicity, we can think of this like a conveyor belt carrying solid rock from India under Asia where it melts and rises under the Himalaya. As the melt nears the surface, it cools once again into granite, like that seen by Noel Odell. The conveyor belt that creates the buoyant granite is the key to Everest’s height and what prevents the mountain from sinking into the Earth’s crust. Geologists call this entire process crustal thickening. And it’s the heat, pressure, transport, and buoyancy of granite created by tectonics that created the tallest mountains on Earth.
Part IV – The High Camps
Sitting on top of the gneiss and granite is the North Col Formation composed of the oldest rocks on Mount Everest, over 500 million years old. The story of these ancient rocks becomes clearer as we take a broader view of the Himalaya and travel back in time, 50 million years ago. As India began to collide with Asia, the smaller Indian plate began to fold against the larger Asian plate, like a rug abutting a wall. At first the rocks folded smoothly and gently, creating long undulating hills. But as the collision continued the folds became steeper and narrower. Eventually, the folds began to overturn and fall over towards the Indian subcontinent, like dominoes, as the tremendous pressure of the collision continued to push at the base of the rocks. When the once undulating folds became so tightly packed together that they could no longer deform, the tectonic forces broke the rocks at the fold’s crests and troughs, allowing the geologic dominoes to slide vertically past one another. These long planes of broken rock, called faults, allowed material deep underground to slide to the surface and allowed large sections of rock to get pushed on top of others. This spectacular and often violent process elevated the ancient rocks of the North Col Formation.
In the spring of 1924, geologist Noel Odell climbed to one of the high camps on Mount Everest perched on the rocks of the North Col Formation. From the banded layers that shone mostly grey under the blaring sun, Odell collected samples that he then meticulously scrutinized. In his report published a year later, Odell could still scarcely contain the joy of his discovery. “At about 25,500 feet I came upon a limestone band which to my joy contained fossils – the first definite forms found on Everest!” Near the roof of the world, Odell discovered fossilized animals that had once lived in a vast and ancient ocean. Ocean rocks… on the highest mountain in the world! All of the rocks of the North Col Formation – the majority of the rocks on Everest – were once sediments depositing in a deep ocean, caught in depressions created as the Gondwana supercontinent formed around 550 million years ago. As the basins filled and the ocean became shallower, the collecting sands and muds began to capture fragments of shells and exoskeletons. Eons later, the tectonic collision that created the Himalayas pushed these rocks and their fossilized records to the surface where Noel Odell so joyously discovered them.
Above Camp IV there was nowhere to hide from the relentless winds. The cold always threatened frostbite. The elevation stole not only energy, but also the ability to eat. At the high camps, the expedition was completely dependent on their gear for protection. By modern standards, the clothing Mallory and Irvine wore might look primitive.2 Instead of down suits that are both windproof and tested at freezing temperatures, Mallory and Irvine wore layers of wool, cotton, and silk. Their jackets were gabardine, a fabric more similar to canvass than the synthetic fabrics used today. Instead of thermally insulated and waterproof boots adorned with titanium crampons that dig into the snow and ice for grip, Mallory and Irvine had leather boots with sharp pieces of metal hammered into the soles. And in the event of an emergency, there were no radios to send for help. At the high camps, Mallory left hand-written notes that were picked up and relayed back to basecamp by other climbers. And then there was the oxygen apparatus.
Mallory wanted to climb Everest without using supplemental oxygen, which he wrote lessened the accomplishment of a summit. But given the delays, he realized that using oxygen was the only way for him to establish the high camps quickly and retain any sort of energy needed for a summit push, even with the clearing weather. On June 1st, Mallory established Camp V at 25,300 feet (7,711 m). The next day, Norton and Somervell replaced Mallory at Camp V and established Camp VI a day later. The team now had a camp at 26,700 feet (8,138 m), but according to Somervell it was “far from ideal.” The camp sat within an exposed rocky basin covered in loose scree that merged with the steep slope of the North Face. When Noel Odell reached this camp several days later, he described it as “perched on a ledge, backed by steep rocks, by no means conspicuous or easy to find.” Regardless, this would be the last camp. While Mallory and Irvine rested, Norton and Somervell went for the summit. They would first have to cross the famous Yellow Band.
Just above where Noel Odell collected samples containing the first confirmed marine fossils on Everest sits the Yellow Band. The Yellow Band is perhaps the most noticeable geologic formation on the entire mountain – a layer of rock roughly 564 feet thick (172 m) that circles the entire mountain and has been stained yellowish-brown from years of weathering. Its color distinguishes it from the surrounding monotony of grey and black stone and identifies an important transition in Everest’s geologic history. Around 514 million years ago, India sat tucked into the north side of the supercontinent Gondwana, just south of the equator. Its northern flank sat within a shallow sea on a continental shelf that teemed with life that flourished in a vast tropical reef that itself sat atop a thickening limestone platform. Then the limestone underwent a particular and peculiar geologic transformation: it changed into a different rock without the normally associated high pressures and temperatures of metamorphism. We needn’t dive into this geological rabbit hole, but the process involved – called dolomitization – indicates a significant change in the local ocean chemistry, and it’s a process that remains only partially understood. To the Everest climber, the Yellow Band serves as an altitude gauge, a slippery slope of rock that must be traversed en route to the summit. To the geologist, the Yellow Band is a reminder not only of the “special elevator forces” that thrust ocean sediments to the top of the world, but also that these forces are subject to change.
Part V – Enveloped in Cloud
At first light, Norton and Somervell left Camp VI and climbed diagonally into the Yellow Band. The rocks of the Yellow Band had been weathered over the years into wider ledges that offered more stability than the scree slopes. But at 27,500 feet (8,382 m), the going was slow. Without oxygen, Norton and Somervell struggled to take around 10 gasping breaths for each step. Somervell, whose throat had hurt ever since the rescue at Camp IV, had to stop at around 28,000 feet (8,534 m). Norton continued un-roped. Without the relative safety offered by the rope, Norton removed his goggles to better see the rocks. He made it to the top of the Yellow Band where Somervell managed to snap a photo of the tiny figure lost among the banded rock. It was a new altitude record, higher than anyone had ever travelled, just 875 feet below the summit. But the decision to remove his goggles would prove costly. In the thin air, the blaring sun attacked his eyes from all directions, even reflecting off of the white snow. Soon, Norton was seeing double and by the next day, he was snowblind. Somervell fared no better. During the descent, Somervell’s throat began to close. He waved Norton past and sat down in the snow just above Camp IV. In desperation, Somervell thrust his closed fists into his abdomen and dislodged a frozen chunk of his own throat lining. He lost the ability to speak for days, but managed to make it back to the North Col able to breathe. As Mallory and Irvine prepared for their attempt, they considered the gravity of these new dangers.
On June 6, 1924, Mallory and Irvine packed their kits at the North Col, ate a breakfast of sardines, biscuits, and hot chocolate, and began their summit attempt. Noel Odell climbed in support, and at 8:40 a.m., he took out his camera and snapped a now legendary photo of the pair of climbers. Beside the open tent, Irvine stood patiently with his back to the camera, his hands in his pockets. Mallory faced forward, resting his weight on his ice axe with his head slightly lowered as he fiddled with the oxygen apparatus. Mallory and Irvine reached Camp V without incident. A day later, they reached Camp VI feeling fit. Mallory scribbled a message in his typically messy script and tore the page from his notebook, handing it over to a porter who carried it back to Camp IV. The message was addressed to photographer John Noel.
We’ll probably start early to-morrow (8th) in order to have clear weather. It won’t be too early to start looking out for us either crossing the rockband under the pyramid or going up skyline at 8 p.m.3 Yours ever, G. Mallory
The final geologic unit of Mount Everest is the summit pyramid, made of rocks slightly younger than the North Col Formation. Similar to the Yellow Band, the summit pyramid is made of limestone originally deposited in a shallow sea. But unlike the Yellow Band, high pressures and temperatures associated with the India/Asia collision have not transformed the rocks of the summit pyramid. In fact, based on reconstructions using mapped faults and rock profiles, geologists have hypothesized that the rocks of the summit pyramid have been horizontally transported from regions 56-134 miles (60-216 km) away. Geologist Noel Odell never reached the limestone cap, but rocks collected in subsequent attempts revealed hidden fossils. Based on microscopic evidence, geologists identified bits of crinoids, or sea lilies, and fragmented bits of trilobite exoskeleton. A whitish band of rock revealed evidence of ancient bacteria that helped bind sediments together in increasingly shallower water. Here, we might share in Odell’s joy and marvel at the discovery that the rocks sitting on the roof of the world formed in an ancient sea that uplifted and dried out around 450 million years ago.
At Camp V, geologist Noel Odell woke early on June 8th, eager to climb to Camp VI in support of Mallory and Irvine and spend the day surveying the geology high on the mountain. Unfortunately, the morning found the mountain covered in mist that brought occasional snow flurries, obscuring Odell’s view of the ridge and summit pyramid. Nevertheless, Odell packed his kit and began his climb. A year later, Odell recalled what happened:
“At about 26,000 feet I climbed a little crag… and as I reached the top there was a sudden clearing above me and I saw the whole summit ridge and final peak of Everest unveiled. I noticed far away on a snow-slope leading up to the last step but one from the base of the final pyramid, a tiny object moving and approaching the rock step. A second object followed, and then the first climbed to the top of the step. As I stood intently watching this dramatic appearance, the scene became enveloped in cloud.”
The two dots, most certainly Mallory and Irvine, had successfully traversed the Yellow Band. High on the ridge, they would have stood atop the rocks of the summit pyramid, some 500 vertical feet below the summit itself. The movement of two black dots silhouetted against the snow and enveloped in cloud was the last time anyone saw Mallory or Irvine alive.
Part VI – The Unknown Land Beyond
Exactly what happened on June 8th, 1924 has been studied and debated for 90 years.4 The primary question is: did Mallory and Irvine successfully climb to the summit of Mount Everest almost 30 years before Hillary and Norgay? If we take Odell at his word, Mallory and Irvine successfully climbed the now infamous Second Step, described by Odell as “the last step but one from the base of the final pyramid.” This would put Mallory and Irvine tantalizingly close to the summit. And even though it was late in the day, it’s easy to imagine the two men pushing forward. But many doubt that Mallory could have climbed the Second Step, a nearly 130 ft. (40 m) wall of broken and exposed rock at 28,250 feet (8,610 m) that modern climbers surmount only with the aid of a ladder bolted to the step. In the years following the 1924 expedition, Odell would often speculate that the two climbers reached the summit before meeting their end. Though at times, spurred by pressure from the climbing community, he would acknowledge the difficulty of the Second Step and even admit that he may have mistook their location on the ridge. In his report on the disappearance written a year later, Odell described his feelings as he climbed high on the mountain in search of his lost friends:
“[The summit] seemed to look down with cold indifference on me, and howl derision in wind gusts at my petition to yield up its secret, this mystery of my friends… And yet as I gazed again there seemed to be something alluring in that towering presence: I was almost fascinated. I realized that no mere mountaineer alone could be but fascinated; that he who approaches close must ever be led on, and oblivious of all obstacles seek to reach that most sacred and highest place of all”
Despite discovering Mallory’s body on the scree slopes below the Yellow Band in 1999, the question of whether or not Mallory and Irvine made the summit remains unanswered.
Noel Odell’s black and white photograph of the two climbers preparing their kits against a background of white snow and ice helps transport us back in time to the golden age of exploration. From Mallory and Irvine, we can trace a line to fellow explorer Robert Falcon Scott. Scott and his Glossopteris fossils helped illuminate continental drift and plate tectonics, which folded and broke the crust and generated the buoyant conveyor belt. Noel Odell noted these “special elevator forces” and gathered samples that proved the marine origins of the Everest rocks. The rocks themselves tell stories of thinning oceans and continental collisions. And, of course, the tiny dots on the summit ridge remind us just how close Mallory and Irvine came to the top of the world, frozen in rocks that formed 450 million years ago. It was a journey that confronted Mallory and Irvine with the forces of Everest, not just avalanches, blizzards, freezing winds, and thin air, but also the powerful and sometimes terrifying forces that created the mountain over millions of years. Buried on Everest’s slope, Mallory’s story is written into the rocks alongside the ancient plants, animals, collisions, and the naked elements of which the world has built itself.
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