Geology hike on the Gold Mine Trail, Sumas Mountain, Whatcom County: conglomerates and a mining scam.

By Dave Tucker

Geologic highlights:

• Two different conglomerates and a potential future conglomerate in the same place;

• An unconformity at the basal contact of the Chuckanut Formation

• Serpentinized ultramafic rock

• Ruins from an elaborate mining scam

Sumas Mountain rises abruptly above the Whatcom County lowlands just east of the towns of Nooksack and Everson. The mountain’s best known geologic feature is the Swift Creek Landslide, slowly creeping down a valley with its load of asbestos-laden clay (take the virtual field trip elsewhere on this website) . This field trip visits the area just north of the landslide. You’ll visit archeological remnants of a gold-mining scam from the early 1900s, including the mine shaft, as well as conglomerate of the Chuckanut Formation. and its contact with the underlying ultramafic serpentine rocks. This guide describes a 3.5 mile loop trail, climbing to 1330 feet. The famously steep Sumas Mountain trail branches off this loop, and ascends relentlessly to the top of Sumas Mountain. That may be a future field trip. Eric Rolfs wrote about the hike to the top of Sumas Mountain and has some photos relevant to the geology described here. His account is posted on his blog, Big Rock Excursions.

GETTING THERE

Trail map based on Google Map image. Click to enlarge.

Find your way to downtown Everson, Washington. Coming from Bellingham, drive east on Mount Baker Highway. Turn north on Everson Goshen Rd, and follow it north until it intersects with E. Pole Rd. Turn east on E. Pole Rd and follow its curves across the Nooksack River bridge into Everson. Continue east through town and past the intersection with WA Highway 9 at the smaller town of Nooksack. You are on South Pass Road (WA 544). 2.6 miles east of Highway 9, turn right on Sealund Road. 300 yards along park on the grass verge just beyond the house; the trailhead is at the corner of the pasture and is signed ‘Gold Mine Trail’. Topo maps: Sumas 7.5′ quad covers this trail, but the trail is not shown on the map. Trailhead is 360′ ASL.

THE HIKE AND GEOLOGY FIELD TRIP

The trail head. Mud starts where the hikers are. You may see shoes drying on the fence posts. Eric Rolfs photo.

The trail starts out in mud. It is pretty much always mud. Deep mud. Just suck it up and walk through it, there is no alternative. Don’t worry, you will, some day, dry out. Muddy boots never hurt a geologist! In summer, the trail may be overgrown for the first 1/4 mile or so, but persevere: it eventually enters genuine forest and your troubles are over. Glacial till (and maybe an old muddy debris flow?) underlies the trail for the first section. The trail eventually traverses above  ‘Gold Creek’ (named after the shenanigans that took place in 1900), the northern fork of Swift Creek. Shortly you’ll come to a crossing of ‘Rankin Creek’- a broken sign may be nailed to a tree here. This creek may be dry in summer.

Large boulder in foreground is a Jackass conglomerate erratic. In the background, the stream flows over much younger Chuckanut conglomerate. The stream bed is filled with eroded sediment- possibly a future conglomerate. Umbrella for scale. Click to enlarge.

Here is the first interesting geology stop of the hike- two different conglomerates and the makings for a future conglomerate. Just before crossing the little creek, the trail goes over the top of a big light-colored boulder. This glacial erratic boulder is conglomerate from the Jackass Mountain Formation of south central BC. (I’ve written extensively about this rock on this website. There are two full pages listing the relevant posts, go here if you want to learn more about, and see other examples of, Jackass conglomerate erratics.) The Jackass Formation is from the mid-Cretaceous Jackass Mountain Group, and this boulder was carried here down the Fraser River valley by Pleistocene ice from the Cascade Range in southern BC, around 15,000 years ago. Jackass rocks can be seen in place in the Fraser River canyon north of Hope, BC, and along the road opposite the lodge at Manning Provincial Park.  The large rounded pebbles in the conglomerate are primarily volcanic and plutonic rocks eroded from the continent and deposited on a submarine fan close to the coast of North America.

The hammer lies against conglomerate of the Chuckanut Fm. Below the log, unconsolidated pebble sediment patiently awaits lithification. Click to enlarge.

At the crossing Rankin Creek trickles over a slab of MUCH younger Chuckanut Formation conglomerate. Chuckanut on Sumas Mountain is also called ‘Huntingdon Formation’, as this is the name applied to the Chuckanut in Canada, and, what the heck, we are awfully close to Canada here! The Huntingdon Formation is described in a 2003 Master of Science thesis by B.H.T. Gilley (Simon Fraser University) and published online. Brett Gilley neatly explains the confusion over these terms in his 2003 thesis: ” The Huntingdon Formation (in Canada) and the Chuckanut Formation (in the USA)…are correlative rocks separated by the so-called “Border Fault”…visible only in the minds of geologists using different formation names for similar rocks on opposite sides of the Canada/US border.” These rocks on Sumas Mountain have yielded a single palynological (fossil pollen) date, and it is late Eocene or early Oligocene, same as the unquestioned Chuckanut a few miles south.  Notice the difference between these two vastly different conglomerates. The edges of the Jackass boulder cut right through the cobbles that make up the bulk of the conglomerate. This results from the great burial pressures that lithified and lightly metamorphosed this marine conglomerate. The rounded pebbles in the Chuckanut protrude from the fine sandy matrix that separates them. This rock has not been subducted nor buried very deep, being subjected only to the much lower burial pressure of whatever thickness of sediment once covered them. The Chuckanut is alluvial, deposited on land in rivers and stream flowing off nearby highlands. The loose stream sediment is also rounded pebbles. Some of these are probably eroded from the Chuckanut, others likely were washed out of the pebble-studded till that blankets everything. The stream sediment, and the till, may someday become yet another conglomerate here, if they survive erosion and are lithified by burial under a LOT more sediment. Assuming the new rock is then exposed by erosion, there will be a real conglomeratic mess here for future geologists to sort out! Makes my head spin!

Beyond Rankin Creek, the trail traverses the edge of a new clearcut. Watch for a signed trail to the left (‘to Cabin’).

Dreams of Gold, by Michael Impero

You’ll descend this trail to complete a loop hike, but for now stay right. You are now watching for a boot-beaten track that descends to the right about 300 yards beyond the Cabin Trail junction. My cheapo GPS receiver says the location is at 48° 54.937’N, 122° 14.889’W. This drops down to a man-made wall of boulders near ‘Gold Creek’. Two 10-foot-high walls come together to make an inside corner. This is variously described as ‘the hotel site’ or the ‘stamp mill site’ for an outrageous mining speculation scam back in 1900. The story is told in considerable detail, with photos, in Michael Impero’s Dreams of Gold (2010, available at Village Books), and more briefly in his earlier book, The Lone Jack, King of the Mount Baker Mining District (2007). Essentially, some swindlers pulled off a bogus ‘gold mine’ in ‘Gold Creek’, bilking distant investors out of a lot of money. The scammers, C.F. Bernard and the appropriately named J. Swinehart, recorded seven gold claims in ‘Gold Creek’ and incorporated the Nooksack Mining Company. They built a wagon road to the site, followed by the trail you have hiked to here. They reportedly constructed a hotel here, a dance hall complete with ‘female companionship’ according to Impero, a bunkhouse for their (unpaid) employees, a stamp mill, and a hydroelectric plant. A Darius Kinsey photo reproduced in Dreams of Gold shows an impressive mill site. There was supposedly even a cyanide concentration system and telephone line to town (Everson). The story has it that the mining company entertained investors and their representatives. In the end, they bilked at least 370 absentee investors out of thousands of dollars, none of whom ever received a cent in return. After it was revealed that the mine was salted and that there was no gold in the rock, the hoaxers seem to have disappeared.

Doug McKeever at the rusted ore cart and the infamous ‘gold vault’. Photo courtesy Eric Rolfs.

The crowning glory of the scam is seen a little further along. Hike up the hill from the wall. You’ll come to a flat spot with a bizarre archeological wonder. A rusted ore cart lies next to a 4-foot-tall tombstone-like iron door in front of a gaping cement  ‘gold vault’. Here, Bernard and Swinehart displayed bags of ‘gold’ they had ‘mined’ from the tunneling operation you will see further up the creek.

If you missed the turnoff trail to the boulder wall, a second right turn descends to directly to the vault. If you miss that, too, the main trail traverses about 30 feet directly above the vault and the mine cart, plainly visible if you keep an eye open, and you can drop down from above. My GPS receiver said the vault is 48° 54.929’N and 122° 14.853’W.

The vault that held the bags of ‘gold’ is made of cement, covered with a rusted iron door. Eric Rolfs photo.

Looking back across the creek near the mine entrance. Chuckanut on one side of the creek overlies ultramafite on the mine’s side.

Back on the trail, it is 200 yards or so to yet another boot track down to ‘Gold Creek’. From the main trail, you can probably see the objective, the dark mouth of a mine adit (a horizontal mine tunnel) in the rock wall across the creek. The stream flows along the unconformable contact between the steeply north-dipping bedded Chuckanut rocks (on the north, or trail side of the creek) and the underlying serpentinite on the south. The adit  is excavated into this serpentinite, and my GPS receiver puts the location at 48° 54.913’N and 122° 14.666’W. The latitude and longitude given in Impero’s book is 1/2 mile to the southwest of the tunnel, across two drainages. Not even my GPS receiver is that bad. Stand on the south side of the creek and look at the conglomerate on the opposite shore right at the water’s edge. You’ll see the bedding dipping away from you- the Chuckanut was deposited directly on top of the serpentinite here, and this is one of the very few places where the base of the Chuckanut can be observed.

The serpentinite rock is part of a late Jurassic ultramafic complex. Ultramafic rocks are igneous and meta-(igneous rocks with low silica content <45%), and higher magnesium and iron than mafic rocks such as basalt and gabbro. Ultramafic rocks are found in the mantle and at the base of oceanic crust. When these rocks come into contact with hydrothermal fluids, metamorphic reactions turn the mafic minerals, such as olivine and pyroxene, into an assemblage of serpentine minerals plus chlorite and amphibole, and the resultant rock is ‘serpentinite’. ‘Serpentine’ is a catch-all name for a family of hydrated, magnesium-rich silicate minerals; the best known may be antigorite and the asbestos family, such as chrysotile. The Sumas Mountain ultramafite is conceivably related to the wedge of mantle rock at the Twin Sisters, faulted into the crust during subduction of an oceanic plate. The Sumas serpentine is soft and weathers to a pale white stone very quickly- a fine example lies in the stream at the trail crossing. This rock may conceivably be confused with quartz veins, which may be ore-bearing.

Scott Linneman at the ‘mine’ entrance cut into serpentinized ultramafic rock. It is a very unappealing hole in the rock.

The adit is low-ceilinged, water filled, and unappealing. I don’t know how long it is, nor was I even tempted to enter it. The serpentinite is soft as rock goes, but still, quite a bit of work must have gone into digging this mine. Perhaps the scam began as well-intentioned mining, but the absence of gold after all that hard work may have suggested an easier way to make some money. There are reportedly at least two other tunnels somewhere along ‘Gold Creek’  but I don’t know where they are.

You can continue your hike to close a loop. Along the way, visit a recently refurbished 100-year-old cabin, now sitting in a clearcut with grand views of lowland Whatcom County, Salish Sea, and the San Juans. This is beyond the steep ‘Lost Lake’ trail junction. “Lost Lake Trail’ gains  2000′ feet to the logged summit ridge of Sumas Mountain.

From the cabin, find a VERY obscure track along the south (left) side of a little gully (do not take ‘Sam’s Trail’). The track descends through the clearcut to the ‘Cabin’ trail junction mentioned above; it is more obvious in the winter and early spring before seasonal brush begins to hide it. You’ll have to splash through the mud again just before you return to your spotless vehicle. You do keep your rig clean, don’t you?