Rooster Rock at Crown Point

Clark described the expedition’s 2 November 1805, encampment differently in his Elkskin-bound journal, and then in his notebook journal:

we Encamped behind a large rock in the Lard. Bend.

we encamped under a high projecting rock on the Lard. Side.

It is an interesting exercise to determine whether the captains and the corps were referring to Crown Point or Rooster Rock in their 2 November 1805, journal entries. The promontory of Crown Point comes to mind when Clark mentions in his notebook journal that the expedition camped “under a high projecting rock,” along with Sgt. John Ordway having the expedition “Camped under a verry Shelving clift on the Lard. Side.”^[2]The author agrees with Moulton, Journals, 6:10n14 that the “high projecting rock” is Crown Point. No correlation between journal descriptions and Rooster Rock were made in the Moulton … Continue reading Precisely where they set up camp could be revealed in Clark’s Elkskin-bound journal when he noted the expedition encamped “behind a large rock,” as did Patrick Gass noting the expedition “encamped at a high peak resembling a tower of the south side.” The isolated pinnacle of Rooster Rock fits a “tower” description nicely and one can easily imagine the expedition encampment in the level glade between Rooster Rock and the vertical Crown Point cliff face; perhaps this was the encampment “green” that Whitehouse alluded to his 2 November 1805, original journal entry.

That Meriwether Lewis utilized Rooster Rock as an ad-hoc river gauge seems evident on the return journey:

[6 April 1806:] from the appearance of a rock near which we had encamped on the 3rd of November last [in error, it was 2 November 1805] I could judge better of the rise of the water than I could at any point below.

Careful comparison of the rock lithology of Rooster Rock and Crown Point have revealed that Rooster Rock is a landslide block off the face of Crown Point,^[3]Wells, et al., “Gorge to the Sea,” 748. yet another example of the inexorable process of mass earth movements in the Columbia River Gorge, even though the intermediate landslide material between Crown Point and Rooster Rock has largely been swept away. And before we exit the Gorge, just as the expedition did when Clark noted on 2 November 1805, that “here the mountains leave the river on each Side,” it’s worth a diversion to discuss how an ancestral Columbia River channel became a towering cliff at Crown Point.

The captains would have been surprised to learn that certain stretches of the Columbia River had occupied several different channels preceding the river that ferried them westward,^[5]The earliest of the last three identified paleochannels, estimated to have formed approximately 15.6 million years ago, extended from The Dalles to under the area of present-day Mount Hood, then … Continue reading and they unknowingly passed remnants of these earlier rivers. The captains had demonstrated an excellent faculty for recognizing “ancient beds of the river” along the Missouri River,^[6]For examples of where the captains recognized “ancient beds of the river,” see pages 177-178 in John W. Jengo, “‘Mineral Productions of Every Kind’: Geological … Continue reading but the paleochannels of the Columbia River in the Gorge evaded recognition until the 1970s and 1980s. Only when geologists began thoroughly mapping unique types of basalt deposits that had flowed into and been cooled by water was it determined such deposits could be differentiated from the flows that had advanced over relatively dry land.

Because the ancestral Columbia River was the low point on the Columbia Plain, it was preferentially filled and erased by certain large-scale lava flows and other deposition events.^[7]CRBG basalt flows filled the two earlier Columbia River canyons per Tolan and Beeson, “Intracanyon,” 463-477, and are called “intracanyon” flows for that reason. Cascadian … Continue reading The river, always unceasingly seeking a pathway to the sea across eruptive flood basalts and through the Miocene-age Cascade Mountains, shifted northward following each river channel-filling episode into relatively low-lying troughs to exploit older and weaker rocks proximal to the northern margin of the more-resistant Columbia River Basalt Group (CRBG) lava plain.^[8]Tolan and Beeson, “Intracanyon,” 476. The ancestral Columbia River system could maintain a prevailing westward flow because of the continued subsidence of the Yakima Belt syncline, which … Continue reading The present-day Columbia River has sliced through some of the former river channels at certain locales, most notably at Mitchell Point (comprised of a canyon-filling basalt associated with the youngest ancestral river channel called the Bridal Veil channel) and Crown Point, part of the older ancestral Priest Rapids channel. So, when the expedition “encamped under a high projecting rock” at Crown Point on 2 November 1805, they were camping near the base of an uplifted 15-million year old Columbia River channel, one of the predecessor watercourses of their route westward.^[9]This is technically called the Basalt of Rosalia intracanyon flow of the Priest Rapids Member, Wanapum Basalt, part of the material that filled the Priest Rapids ancestral Columbia River channel. Up … Continue reading