Contents

Niagara Falls

Cave Map Showing the Location of Niagara Falls (Source: Oregon Caves Image Library)

Niagara Falls provides one of the best examples of flowstone. The room also contains evidence of human impact, notably pencil writings and formation damage. In addition, flooding resulted in the destruction of many soda straws, a number of which are now cemented to the floor.

Geology

Cave Formations

Niagara Falls is dominated by a sheet of flowstone that nearly fills the entire room. Covering this entire formation are numerous pencil writings dating mostly from the late 1800s. Attempts at erasing these writings in 1917 were unsuccessful, due to actively Flowstone With Broken Formations in Niagara Falls (broken formations are in upper left of photo) (Source: Oregon Caves Image Library)forming flowstone that had deposited a thin layer of calcite over the writings. The actual thickness is not known, but is likely less than a hundredth of an inch. This indicates a deposition rate of less than one inch every 10,000 years. In addition to the graffiti, human impact can also be seen in the rows of broken stalactites.

Cave popcorn is also present in Niagara Falls, which receives airflow from the 110 exit (Roth 28; Hill and Forti 691). Soda straws and small columns can be seen past the flowstone, too. Along the path, drapery hangs down over the trail.

Human Impact in Niagara Falls Includes Pencil Signatures from the Turn of the Century (Source: Oregon Caves Image Library)

Water Flow

Formation growth is largely dependent on the flow of water into the cave (Hill and Forti 691). Water tends to move down between rock layers slanted into the mountain side (Roth 28). Because passages interrupt water flow, this likely is the reason there is a great deal of flowstone on the right side of the passage and there is hardly any flowstone on the left side of the passage.

Visible on the floor of Niagara Falls are broken soda straws that have been cemented to the ground. These formations were broken prior to human-induced damage. Sediment may have plugged up the passageways, resulting in flooding that broke off many of the formations on the ceiling (Rosales 1; Roth 28-29). The soda straws were then cemented to the floor as calcite-saturated water began to flow on the ground.

 

References

Hill, Carol and Paolo Forti. “Speleothems: Carbonate.” Encyclopedia of Caves and Karst Science. John Gunn, ed. New York: Fitzroy Dearborn, 2004. 691-692.

Rosales, Alicia. “Cause of Speleothem Breakage Prior to 1874 in Oregon Caves National Monument.” Cave Junction: Oregon Caves National Monument, 2006. 1-2.

Roth, John. “Interpretive Manual for the Monument’s Showcave”. Cave Junction: Oregon Caves National Monument, 2011. 28-29.