June 2012. It’s a warm summer day and, after a year of planning, we’re off with friends to find the site of the Blue Lake Rhino. We’re in Grant County, in Central Washington … just south of the world famous Dry Falls (made famous during the end of the last Ice Age). It’s sunny, hot, and dry.
Millions of years ago, however, during late Miocene and early Pliocene (between 17 and 6 million years ago), enormous quantities of basaltic magma flooded the surface of eastern Washington (these ‘Columbia River Basalts’ also covered portions of Oregon and Idaho). Over a period of about ten to fifteen million years, these gigantic lava flows repeatedly poured forth. Eventually, an area exceeding 60,000 square miles (which is an area larger than the entire State of Georgia … it was big!) of the Pacific Northwest was buried in lava, some areas over a mile thick. Buried in one of these lava flows – in the middle of Washington – was a rhinoceros. No kidding.
The fifteen to fourteen million year old fossil mold - commonly know as the "Blue Lake Rhino" – was discovered in 1935 by rockhounds searching for petrified wood. The unusual fossil mold of a small rhinoceros is located high up on a basalt cliff in the Columbia Basin Plateau lava field above Blue Lake. The fossil mold, which forms a small cavity, is preserved in pillow basalt overlying a thin sand bed. A few bones also were found. Scientists believe that, at the time of one of the lava floods, the rhino likely was dead and laying in a small pond. Lava then flowed into the water and hardened, forming a mold around the rhino’s body. Scientists from UC Berkeley made a mold of the rhino (and made off with most of the few bone fossils which existed at the site and which now are stored in California). A mold of the rhino can be seen at the Burke Museum in Seattle (at the University of Washington).
Intrepid adventurers still can see the fossil mold of an upside down rhino in the basalt cave. And, if you are my size, you can climb inside. Just one problem … it’s located on a cliff face about 300 feet above the east end of Blue Lake, approximately 25 miles north of Soap Lake, Washington near Sun Village Resort. The basalt cliff wall is marked. Access is dangerous. The climb is steep, on unstable talus, and there is no safety net. Approximately 300 feet above the basalt boulders below, you can stand on a cliff ledge – about three to four feet wide – and look inside the basalt cavity. Take a flashlight and nerves of steel. Seriously, unless you are experienced, this is a dangerous climb that should be avoided.
Scientists are not completely confident as to the exact specimen, but many believe the Blue Lake Rhino to be a Diceratherium – the double-horned rhinoceros ancestor first named by Othniel C. Marsh, the famous U.S. paleontologist who persuaded his wealthy uncle to fund a museum at Yale. Marsh named several dinosaurs.
We made it safely up to the cave and back and, while we were climbing the cliff, my pal Carol fiercely protected my lunch – especially my Cheetos – from a determined group of horses. Thank you Carol. If you’re lacking someone to guard your lunch or just don’t think you want to risk the cliff, you can see a small model (and a few small bone fragments) of the Blue Lake Rhino at the Visitor Center at the Dry Falls Heritage Area.