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SCHREIBER BEACH​

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Schreiber Beach nestles deep within the majestic landscape of the central Ontario shore. The beach is flanked to the north by a massive hillside, to the east by a long forested headland, and to the west by pillowed outcrops that tell the story of the birthing of earth’s early lands from the watery depths of ancient seas. Cradled by the emptiness of the lake and steep folds of surrounding land, it evokes a profound absorption. I stand alone on the upper sands listening to the sound of a gentle surf wash in from Collingwood Bay until it meets a cordon of trees along the upper beach that deflects it back toward the water. Blurring the boundaries of land and lake, the echoing surf envelops the beach in a timeless call and response. 

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After rounding the far northwestern corner of the lake at Nipigon, the Ontario shore winds steadily southeast until it reaches Collingwood Bay. The bay is partially sheltered by Copper Island, the final island in a long line of progressively smaller islands that arc around Nipigon Bay and extend east to the Schreiber Channel. Climbing to nine hundred feet at Mount Gwynne, the headland that guards the eastern side of the bay angles one and three quarters of a mile into the lake to end in a broad tip called Schreiber Point. All along the surrounding coast, steep hillsides, bays, and points repeat the same dramatic topography. Rossport Point, Crow Point, Rainboth Point, and Grant Point, each point protects its own bay. Worthington Bay, Terrace Bay, Victoria Bay, and Jackfish Bay, the names sometimes double as the names of towns. 

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My gaze skims the outer headland and bay and then circles back to the beach and fastens on an outcrop to the west, a reassuring anchor against the imposing scale of the land. Reaching from the forest to the water, the outcrop faces the beach with blue-gray walls and mounds and at its top harbors scattered small cedars, shrubby cinquefoils, and ragworts, as well as two large, gleaming brownish spheres. A watermelon-sized sphere with a finely cracked bluish skin pokes up from the fractured rock along the lower wall and shallow bands ribbon around the shapes of contorted ovals on the outcrop’s pale aqua-gray tip. Bleached by the rays of the midday sun, the pastel-tinted, waterworn tip creates a startlingly unusual-looking area of rock. As I bend low over its strange forms, the lake and headland nearly disappear from view and the rock quickly draws me in. 

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The ovals and spheres are the remnants of pillow-shaped lobes of basaltic lava that flowed up from vents onto the ancient sea floor. As the basalt came into contact with the cold water, its outer surface quickly hardened to a glassy rim that swelled like a balloon from the buildup of still molten lava within until it eventually cracked open and allowed a new lobe of lava to surge forth. The new lobe in turn moved only a short distance before its surface too hardened to a pillow with a glassy rim.1 Over time, the pillows spread out and built up plateaus of ocean crust and here and there towering stacks that penetrated the water’s surface and birthed new lands.

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Like other areas of pillowed rock at Schreiber Beach, the outcrop in front of me mostly displays cross-sections of pillows that were shorn off during geological upheavals and later polished by the glaciers. Intact, three-dimensional lobes are much rarer, though scattered humps and spheres still appear. Contact with seawater heated by the lava resulted in a low grade metamorphism that changed original minerals in the basalt into green-colored secondary minerals such as chlorite, which give the rock a distinctive tint. The pillow rims are especially rich in chlorite and at the outcrop’s tip create slightly sunken, satiny-smooth aqua-blue and teal bands around the more textured and variously tinted cores. To the west of the beach, a long sequence of outcrops separated by small coves extends down the coast, part of the thick stack of underwater lava flows that built up this stretch of shore.2 While the outcrop in front of me formed from lava that cooled into pillows, other outcrops that I’ll cross over the next few hours solidified from hotter lavas that remained too fluid to create pillows.

 

The outcrop’s tip is well exposed today, but I’ve sometimes arrived on the beach to find it partly concealed by a buildup of gravels or submerged by waves. Each pillow has a slightly different size, shape, and tint. While the ovals on the walls higher up on the beach have less delicate colors than those at the outcrop’s tip, they offer a clearer display of the interlocking arrangement of pillows that formed within a lava stack. Instead of an ovalish shape, one pillow has a broad rounded upper edge and two concave sides that end in a pointed cusp that fills in a dip between two underlying pillows. In cases where the rock was later rotated or tilted, the cusp allows geologists to determine the original direction of the bottom of a lava stack. 

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Exposed pillow basalt accounts for only a sliver of the Superior coast and Schreiber Beach is the only place I see it during my travels. Though I automatically think of the phrase pillow lava as a single geological term, and not as a pairing of two separate words, the connotations of comfort and shelter implied by the former word seem an apt mirror to the sentiments the beach today evokes. When I first visited the beach over two decades ago, however, a narrow, winding dirt road made the steep descent from the outskirts of the town to the bay. The road was muddy from heavy rains and I worried that my car wouldn’t make it back up and pulled to the side and walked down the final half of the hill. On reaching the deserted beach, I felt an acute sense of vulnerability before the looming headland and endless empty waters and outcrops. I quickly walked around and then left. For many years thereafter, I passed the beach by.  

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By the time I returned, the road had been paved and a pavilion, trail signs, and composting toilet put up at its base. My unease persisted, but I walked to the outcrop at the far end of the beach and, struck by the appeal of its soft, pastel-tinted humps and rims, took a few photographs before returning to my car. The following summer I again stopped at the beach. My visit lasted no more than fifteen minutes, but what I saw in that time filled me with so much wonder that I could barely force myself to leave. Gradually as I continued to visit, the beach unveiled one remarkable patch of rock after another. The more I trusted it to show me how to find grounding, the further west I ventured, and the more my early trepidation gave way to a new acceptance of the inherent fragility and smallness of being human amid the grandeur of the shore. 

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✧

 

White-painted arrows and cairns mark the way as I wander inland from the beach and wind up a rocky slope with young aspen and birch to follow the Casque Isles trail into the forest. Schreiber Beach serves as an access point for the Casque Isles hiking trail, which runs for thirty-two miles between the towns of Rossport and Terrace Bay and takes its name from the French word casque or helmet. The word was used in a book entitled The Shoe and Canoe to describe the shape of islands to the east by the English physician and geologist John Bigsby, a member of the international survey commission that defined the U.S.-Canadian boundary in the 1820s.3

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The town of Schreiber, meanwhile, got its start as a supply depot and tent town for construction workers with the Canadian Pacific Railway in the early 1880s. Initially called Isbister’s Landing after the engineer credited with building the Schreiber segment of the railway, it was later renamed after chief railway engineer Collingwood Schreiber. Construction supplies were unloaded from steam barges on the beach and moved up the steep hillside in mule-drawn carts to complete the rail station in Schreiber and final stretch of the line between Winnipeg and Montreal.4 Once the first train rumbled through in late 1885, the town grew as a service and repair terminal and home site for railway workers. I’ll eventually hear the rumble of a freight train from atop the hillside while wandering west across the outcrops, but as I leave the beach for the forest all thoughts of the town up the road vanish. 

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The trail cuts a narrow path between towering aspen and birch and carpets of clubmoss, wild ginger, bluebead, and Labrador tea. A moose has left fresh droppings amid its roots and stones. No sooner have I begun to settle into my walk than I reach a short spur and return to the coast. “Your Superior Experience Awaits” reads the caption on a brochure in a box near the end of the spur. I step from the forest onto a flat-topped ridge with a giant pair of red Adirondack chairs, one of over a hundred similar pairs placed across Canada to encourage Canadians to explore their natural and cultural heritage. Sitting down in a chair, I take in a spectacular view of the headland, slumping outcrops, and long squat profile of Copper Island.

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Though tempted to linger, I soon head downslope to explore the lakeside rock. The chairs sit high above the water and as I descend across uneven mounds and blocks I’m struck by the near absence of vegetation. The height and inland reach of the rock offer adequate shelter from storm waves, but too few places seem to exist in which soils can gather and seedlings gain a foothold. Yet occasionally I pass a crevice with a cushion of moss and a few bird’s eye primroses, Kalm’s lobelias, or knotted pearlworts. The knotted pearlwort is a low arctic and subarctic plant with tufts of spikelike leaves that stand no taller than my pinkie and delicate white flowers that reach beyond the leaves’ margins.5 The flowers measure a mere eighth to a quarter of an inch across and sit on thin, branching stems that include pairs of narrow leaves that grow progressively smaller toward the stems’ tops. 

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Most plants are less prolific, but one pearlwort that I see sports a total of eight branching stems with twenty open flowers and a few seed capsules that shift between lime-green and red. Hiding in the axils of the upper leaves are minuscule shoots known as bulbils, which eventually fall off the stem and try to take root and birth new plants.6 I pull out my hand lens and bend low over the plant. Its bulbils measure less than one millimeter apiece and have short, stiff centers and tiny claw-like leaf bunches, which give the stems a knotted appearance.7 While some have a yellowish or reddish cast, most larger bulbils have turned bright green. In the damp moss around the plant are several bright green specs barely visible to the naked eye, along with a few miniature tufts of spikelike leaves, likely seedlings or bulbils that have fallen off the plant and germinated. I spend a good fifteen minutes bent over the plant and moss, observing, photographing, and recording in my notebook. When I finally stand up, my mind reels from the abrupt shift in scale between the diminutive bulbils and spikes, on the one hand, and headland and open lake, on the other.

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Continuing downslope, I reach a broad, unevenly mounded area of rock along the water with an impressively crisp pattern of flat pillows. The pillow forms range in size from large ovals of over two feet in diameter to small circles of only four to six inches. While the rock’s surface overall has a pale yellow-gray cast, the pillow cores shift between tints of orange, green, and blue and often include tiny vesicles and thin cracks. The rims, meanwhile, are mostly blue-gray or in a few cases inky black. The outcrop has a less delicate appeal than its paler counterpart by the beach, but between several of its pillows are elegant yellowish wedges with shards of pillow material that shattered in the cold water and was cemented by quartz and calcite, or angular pockets marking places where shards have weathered out.8

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I wander toward a short wall that angles toward the water, its vertical face broken by a large missing chunk that must have been plucked by the glaciers, whether all at once or piece by piece. The missing chunk creates a three-sided room with a flat floor and shoulder-high walls covered in finely polished pillows. Stepping into the room, I enter my own private corner of an immense stack of lava that helped layer up the hard crust of what became the gradually assembling core of North America. As I look at the varied shapes and hues of the pillows up-close, abstract geological processes begin to take on solid, intimate forms. 

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Hoping to learn more about the pillowed outcrops, I had visited the beach a few years earlier on a field trip organized by the Institute on Lake Superior Geology, which was holding its annual meeting a ten-minute drive to the east in Terrace Bay. A busload of geologists, students, and laypeople had joined Seamus Magnus of the Ontario Geological Survey for a daylong excursion to explore the western section of the Schreiber-Hemlo greenstone belt, a thirty-mile long band of deformed rock that snakes east from Collingwood Bay to the Coldwell Peninsula. A tall, affable man with a knack for explaining complicated geological processes in easily comprehensible terms, Magnus had spent several field seasons mapping the belt’s western or Schreiber region.

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The greenstone belt had its origins around 2.7 billion years ago at an ocean trench, a place where two of earth’s migrating tectonic plates converged and one plate descended under the other.9 A rising plume of basalt from the hot mantle below built up a plateau of basalt on the seafloor adjacent to the trench and as the subducting plate descended into the Earth's mantle, heating up to the point where it partially melted, a less dense basaltic magma rose back up from the mantle to create an arc of volcanic islands.10 Additional lava eventually flowed onto the seafloor from a rift that formed behind the arc as the ocean’s crust stretched and thinned.11 Island arcs like that associated with the Schreiber-Hemlo greenstone belt migrated across the ocean with the movement of the tectonic plates on which they sat, all the while shedding eroded sediments into offshore basins. Eventually they collided at trenches and their lands crumpled into mountain chains whose bottoms descended, heating up to the point where they metamorphosed and in some cases partially melted to form granitic magma. Large bodies of this granitic magma infused with lightweight elements from the earth’s crust rose toward the surface and enveloped the islands, forming larger landmasses.

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During later landmass collisions, the wet, dense basalt descended back into the mantle while the buoyant, overlying granite gradually assembled into proto-continents. Surrounded by large bodies of granitic rock, the eroded island arcs over time came to form long, contorted bands called greenstone belts after the tint of their metamorphosed basalt.12 The Schreiber-Hemlo greenstone belt and its associated lands eventually joined with other migrating lands to create a geologically distinct terrane that today covers most of Lake Superior’s Canadian shore. Known as the Wawa-Abitibi terrane, this terrane in turn assembled with yet others to create the Superior Province, which contains the oldest known rocks within the Canadian Shield and forms the hard core of bedrock around which the North America continent gradually took form. Each stitching together of lands and each upwelling of granite moved the Schreiber-Hemlo greenstone belt further from the open ocean until it sat far in the continent’s interior. As if reluctant to leave its watery origins behind, however, the belt now bounds the northern edge of the world’s largest inland sea.

 

Over the past two decades, the Canadian government and province of Ontario have taken extensive strides to preserve the lands and waters of the lake’s northern shore. The hillside and outcrops west of Schreiber Beach are part of Ontario’s Lake Superior North Shore Conservation Reserve, which protects nearly ten miles of coastline around Collingwood Bay, Grant Point, and Worthington Bay.13 The waters of Collingwood Bay, meanwhile, lie within Canada’s Lake Superior National Marine Conservation Area, one of the largest freshwater marine conservation areas in the world. Established in 2015, the area reaches south to the U.S. border from the tip of the Sibley Peninsula in the west to Bottle Point near Terrace Bay in the east and covers roughly one eighth of the lake’s total surface, as well as twenty-three square miles of islands and mainland coast. It joins the protected lands of Pukaskwa National Park and several Ontario provincial parks in securing a future in which long stretches of the Canadian shore will remain accessible to the public and free from significant further development.

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As I continue west across the outcrops from the red chairs, the coast soon drops into a cove with a beach of blue-gray cobbles and a heap of boulders at its far end. Inland of the boulders, along the edge of the forest, common ninebarks, sweet gales, and butterworts fringe a picturesque pool with a short mossy wall studded with lime-green lichen. Runoff from the forest cascades down the wall and garnishes the dark surface of the pool with translucent bubbles and swirling tendrils of foam. From the pool, the trail leaves the outcrops for a longer stretch through the dim, damp understory of the forest. Towering exemplars of spruce, aspen, fir, and birch join mossy rock walls to give the woods a solemnity I don’t often encounter further south. On the ground, plush mats of feather moss with bunchberry, twinflower, and three-leaf goldthread ease over rotting stumps and boulders. Hummocks of sphagnum moss host stemless lady’s slipper orchids, Labrador teas, and fine latticeworks of creeping snowberry, creating a lush arabesque of greenery.

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I eventually leave the forest again for the sun-baked outcrops, squinting into the harsh light as I step onto a long knoll of rock that slopes unevenly toward the lake. Bounded to the east by a watery inlet and to the west by a boulder-strewn dip, the knoll is covered in a dense skin of lichen that in a few places toward its inner edge parts to reveal a surface of tightly packed angular rock pieces. The pieces range in size from around one-half of an inch to several inches and eroded from volcanic lands during a long pause between lava flows.14 Cemented into a base of finer sediment, they create a type of rock called breccia, which I rarely see in the places I visit around the lake except for on occasional boulders. One patch of breccia features cream-colored and whitish pieces in a grayish base while an iron-stained adjacent patch instead has yellow and peach-colored pieces in a rust-brown base. Downslope, sinuous brown, black, and dark orange splotches weave around larger pieces of pale, water-smoothed rock. I slowly circle around the outcrop in hopes of finding more pieces, but finding none continue down the coast toward the next cove.

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Each cove presents a distinct environment, with one or two features that draw my eye. In the cove that I soon reach now, shimmering humps of rock dip toward the water and a tongue of blue-gray cobbles slopes inland to fill in a trough between two sets of outcrops. A few harebells and small wild roses lurk between the upper cobbles and ninebarks and shrubby cinquefoils dot the edge of the forest. The cove brims with pale cobbles and colorful flowers and shrubs and despite its openness to the lake imparts a nearly hidden sense of seclusion. As I sit down on a hump of rock, the light surf washes back and forth across the lower beach and frames the outcrops that run down the coast. I’m struck by how the lake isn’t merely the vast, shapeless presence that I usually take it for, a constant at the periphery of my vision that I pay little attention to as I explore the shore. Instead, the empty waters seem to clarify and define the outcrops, magnifying their features and paring the rocky coastal strip down to a scale that I can comfortably take in. Sliced between the forest and lake, the strip focuses my gaze and simplifies my choices, offering a solidity and sense of direction that a forest with a maze of trees or grassland with a mesh of supple stems could only partially do.

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I watch the surf curl around the cobbles for a while and then open my pack and pull out a simplified geological map that Magnus had included in his field trip guide.15 The map uses Roman numerals to mark each of the twelve, progressively older lava flows that appear between the beach and a pair of inlets called Twin Harbours slightly over a mile to the west. In addition to basalt, the outcrops include minor areas of rhyolite and diabase, as well as sedimentary rocks laid down as the land shed eroded sands and stones between lava flows.16 While the oldest lava flows sit directly on top of each other, three of the subsequent flows are separated by thin northwest-striking bands of sedimentary rock. I can’t tell exactly where on the map the brecciated knoll that I crossed to the east sits, but suspect it may be atop of flow VIII. A slightly wider band of sedimentary rock appears atop flow V to my west. 

 

My field guide describes the band as a sequence of conglomerate with pebble- and cobble-sized stones likely deposited in a shallow water environment similar to that around the cobble beaches of the current shore.17 Conglomerate is a close cousin of breccia, but is made of rounded, waterworn instead of angular pieces. According to my map, the first area of conglomerate should sit just beyond a cove to the west. I gather up my pack and after crossing a series of steep, angular outcrops quickly reach the cove. The cove is larger and deeper than its earlier counterparts and strewn with blocks and boulders that transition to smaller stones further inland. Nearby are pillowed outcrops with far bolder and more varied surfaces than those closer to the beach. Some flat pillows have pale blue-gray cores and mint-green rims while others have umber-brown cores and metallic blue rims, or they have orange or red-brown cores and blackish rims, intense colors pulled out by oxidation. Elsewhere the rock is heavily fractured and embedded with broken pieces in assorted shapes and sizes, or it swells with bulbous pillows with cracking skins.

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From the uneven rock along the water, a broad ridge capped by a thick layer of conglomerate gradually rises inland to a tall neck. A second neck parallels the lake slightly to the west and is separated by a desolate stretch of dark craggy rock from a third, more expansive area of conglomerate, which I reach after clambering up a cut in a wall. A magnificently broad slope capped by a thick layer of conglomerate bucks up from the water to dwarf the surrounding coast. The slope descends steeply lakeward along its lower reaches and, though heavily lichenated above, closer to the water has a clean, even surface of mostly gray pebble and cobble-sized stones. The nearside of the slope creates a distinctive angle with a missing window of rock, which I immediately recognize from a photograph that Magnus had sent me after the field trip. 

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I wander as far down the slope as I can, peer into the water, and just under the surface see a small reef with several pale oblong mounds. The reef, Mangus had indicated, is made of stromatolites, fossilized structures built on the ancient seafloor by early cyanobacteria. Cyanobacteria were the first organisms to produce oxygen as a byproduct of photosynthesis and as they spread across the seafloor around earth’s early lands eventually released enough oxygen to create an atmosphere capable of sustaining more complex life. The oxygen gradually reacted with the sun’s ultraviolet radiation to surround the earth with a protective layer of ozone, which around 430 million years ago allowed life to begin moving out of the water onto land. The light-seeking cyanobacteria grew in thin layers and secreted a slimy coating that protected them from solar radiation but also trapped bits of rock and sediment eroded off nearby lands.18 Repeatedly buried by fresh muds and sands, they grew upward in new layers and over time created domelike structures and reefs. 

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The reef sits in the silica-rich sediments of a fine-grained rock known as chert, which underlies the conglomerate on which I stand and also creates an outcrop with a more substantial collection of stromatolites roughly two miles to the west, in the Schreiber Channel Provincial Nature Reserve. This is my fourth attempt to see the stromatolites, which Magnus discovered while mapping the coast. On my first two attempts I hadn’t ventured far enough down the coast while on my third rough waters had prevented me from seeing anything but the shadowy contours of the reef. Now, I excitedly walk around taking notes and photographing, all the while marveling at how complete a geological record this short stretch of shore holds, from the emergence of earth’s early lands to the emergence of its early life forms. 

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Before walking back to the beach, half an hour later I sit down on the slope. The long arm of Copper Island hunkers low across the water and to my east the headland by the beach juts into the lake. To my west low-lying outcrops run toward the mouth of Blind Creek and a long forested protrusion of land. Like the island, outcrops, and headland, on the scale of geological time, the slope will soon erode back into the cradle of the lake. Yet at least for the duration of my lifetime, its stones will likely remain as solidly cemented as the pale mounds in the fossilized stromatolite reef. The light surf rises and falls below me. In its steady rhythms, minutes, hours, and even years lose all meaning until all that remains is an infinite stillness, a boundless unison that rises up from the water and draws all life back to its source. 

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1. Steven N. Carey, Submarine Conditions, “Understanding the Physical Behavior of Volcanoes,” in Volcanoes and the Environment, edited by Joan Marti and Gerald Ernst (Cambridge, UK; New York: Cambridge University Press, 2005), 29-31; Gene LaBerge, Geology of the Lake Superior Region (Tuscon: GeoScience Press, 1994), 26-27.

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2. Seamus Magnus, Stop 8. Schreiber Beach Outcrops, “Geology of the Western Schreiber-Hemlo Greenstone Belt,” in Institute on Lake Superior Geology Proceedings, 65th Annual Meeting, Terrace Bay, Ontario, Part 2 - Field trip guidebook, edited by Al MacTavish and Pete Hollings, 65, part 2 (2019), 32-34.

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3. John Jeremiah Bigsby, The Shoe and Canoe: Or, Pictures of Travel in the Canadas, vol. 2 (Paladin Press, 1969), 216.

 

4. Barbara Chisholm and Andrea Gutsche, Superior: Under the Shadow of the Gods (Toronto: Lynx Images, Inc., 1999), 187.

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5. David R. Given and James H. Soper, The Arctic-Alpine Element of the Vascular Flora at Lake Superior, Publications in Botany, no. 10 (Ottawa: National Museums of Canada, 1981), 8.

 

6. Aaron Kitching, Knotted Pearlwort, Sagina nodosa, Wildflower Web, accessed February 20, 2024, http://www.wildflowerweb.co.uk/plant/364/knotted-pearlwort; Knotted Pearlwort, Sagina nodosa, Nature Gate, accessed October 9, 2018, https://luontoportti.com/en/t/317/knotted-pearlwort.

 

7. M.R. Penskar, “Special Plant Abstract for Sagina nodosa (pearlwort),” Michigan Natural Features Inventory, Lansing, Michigan, accessed October 9, 2018, https://mnfi.anr.msu.edu/abstracts/botany/Sagina_nodosa.pdf.

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8. M.W. Carter, Geology of Schreiber-Terrace Bay Area, District of Thunder Bay, Ontario Geological Survey, Open File Report 5692, 1988, 20; LaBerge, Lake Superior, 26.

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9. I am grateful to Mark Puumala for commenting on and correcting the description of the formation of the Schreiber-Hemlo greenstone belt.

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10. Ali Polat, Figure 16, Simplified Geodynamic Evolution of the Schreiber–Hemlo, Manitouwadge, and Winston Lake Greenstone Belts, in “The Geochemistry of Neoarchean (ca. 2700 Ma) Tholeiitic Basalts, Transitional to Alkaline Basalts, and Gabbros, Wawa Subprovince, Canada: Implications for Petrogenetic and Geodynamic Processes, Precambrian Research 168 (2009): 101.

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11. Seamus Magnus, Field Trip, “Geology of the Western Schreiber-Hemlo Greenstone Belt (Institute on Lake Superior Geology, 65th Annual Meeting, Terrace Bay, Ontario, May 7, 2019); Polat, Figure 16. I am indebted to Seamus Magnus for his clear explanations of the complex geology of Schreiber Beach and generosity in responding to questions both during the workshop and later via email. Any errors in information are my own. 

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12. LaBerge, Lake Superior, 24.

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13. “Lake Superior North Shore Conservation Reserve, Statement of Management Interest,” Ministry of Natural Resources and Forestry, Ontario, January 27, 2017, https://www.ontario.ca/page/lake-superior-north-shore-conservation-reserve-management-statement.

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14. Magnus, Field Trip.

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15. Magnus, Figure 9, “Geology of the Western Schreiber-Hemlo Greenstone Belt,” 33.

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16. Magnus, Field Trip.

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17. Magnus, “Geology of the Western Schreiber-Hemlo Greenstone Belt,” 33.

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18. Jon Nelson, “Stromatolites: Our Mysterious Ancient Reefs,” Lake Superior Magazine 19, no. 2 (April 15, 1997), https://www.lakesuperior.com/the-lake/natural-world/192feature/.

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