Whiskey Run Geology

Is it possible that gold wasn’t found at Whiskey Run until the early 1850s because it wasn’t there?

While writing Whiskey Run Gold Nearly Missed!, I wondered how early travelers could have missed the gold on the beach. I imagined a variety of possibilities:

• They didn’t realize the glimmering particles in the black sand were gold.
• They were tired and weary from travel and simply weren’t paying attention.
• They set up camp at dusk and broke camp at dawn, not seeing the beach in full daylight.
• They were dealing with stormy weather and solely focused on traveling towards their destination.
• They were trudging through water as ocean waves rushed onto the beach.
• Or, the gold wasn’t there.

While unrecorded human thoughts and behavior are lost to time, the last possibility can be investigated by examining the geological context of gold.*

Gold

There are two kinds of gold: placer deposits — loose particles of gold mixed with rock sediments; and lode deposits — gold embedded (as veins) in hard rocks.

Placer deposits lay at Whiskey Run, brought by the Coquille River from the Cascade mountains.

The following overview describes three sets of geological processes that contributed to the appearance of gold at Whiskey Run.

Mountain Erosion

For millions of years, geological processes such as earthquakes, surface weathering, and landslides, eroded lode deposits in the Siskiyou Mountains.
(The Siskiyou Mountains are a subrange of the Klamath Mountains, which are a part of the Coast Range.)

Water drained from the mountains, moving eroded rock sediments and gold particles as it flowed toward the ocean. A coastal plain between the mountains and the ocean formed as the sediments flowed away from the mountain. Larger grains of gold settled in sediments closer to their source, while smaller particles continued to move downstream. Heavier than rock sediments, the gold particles sank toward the bedrock, and rock sediments covered them.

River Transportation

The four forks of the Coquille River (North Fork, East Fork, Middle Fork, South Fork) join near Myrtle Point, forming a main river stem that drains into the Pacific Ocean. The South Fork is the only one that has its headwaters in the Siskiyou Mountains: it’s the fork that carried gold over the coastal plain. Carried on by the main stem of the river, the gold came to rest in the marine sands.

The river is illustrated in the left upper quadrant of the map below. (Note: State Highway 42 follows the middle fork and USFS Route 33 follows the south fork from Highway 42 to Eden Valley.)

Ocean Dynamics

In the early 1850s, the mouth of the Coquille River ranged over the area that is now Bullards State Beach Park. However, thousands of years earlier, the ancient mouth of the river was located between Cut Creek and Whiskey Run Creek, the stretch of beach that would be buzzing with goldminers in 1853.

The map below shows the old channel of the Coquille River, south of Fivemile Pt.

After the river deposited gold on the ancient coast, natural forces such as wind, rain, landslides, and ocean waves, eroded it into even smaller particles. Ocean waves helped separate the sediments, concentrating particles of gold in layers of black sand on the beach.

Strong ocean tides and storms periodically altered the size and shape of the shoreline; they also altered the composition of beach deposits. One way this happened is shown below: Ocean waves cut notches into the base of a bluff (cliff), eventually causing the bluff to collapse, releasing sediments–including placer deposits–onto the beach.

As shown below, the bluff at Whiskey Run contained marine sands that were deposited during the Pleistocene epoch (2.6 million – 11,700 years ago).

The geological processes that exposed the placers on the beach—that is, storms and tides, are the same processes that washed the gold from the beach in the winter of 1854-1855.

The geologist, J.T. Pardee, observed that over time the Oregon coast beach not only changed in size and shape, but also in sediment and mineral composition: “a stretch of beach that is barren on one day or in one season may be productive at other times” (1934, p. 34).

In other words, it’s possible that gold wasn’t exposed on the beach before the early 1850s.

Summary

The geological processes described above don’t reveal when gold first became visible on the beach, but they explain how it came to be there.

Overall, geology provides an answer to my research question: Yes, it’s possible that gold wasn’t found at Whiskey Run Creek until the early 1850s because the sediments in the bluff hadn’t yet eroded onto the beach.

Regardless of when it first appeared and whether or not it could have been overlooked, the story of Randolph begins with the discovery of gold, the subject of the next post.

Sources

Baldwin, Ewart Merlin. “The Ore bin ; Vol. 28 No. 11 (November 1966).” ScholarsArchive@OSU. Oregon Department of Geology and Mineral Industries, November 1966. https://ir.library.oregonstate.edu/concern/administrative_report_or_publications/4t64gs713

Pardee, J. T. “Beach Placers of the Oregon Coast.” Circular. Circular. Washington D.C.: Department of the Interior, 1934. https://pubs.usgs.gov/publication/cir8

* For a comprehensive, easily readable, and well-illustrated explanation of the geology of gold, this three-part series written by contemporary gold-miners might interest you:

• Where does placer gold come from? Part 1.
• Where does placer gold come from? Part 2.
• Where does placer gold come from? Part 3.