The Ringold Formation is a geological formation in Eastern Washington, United States. The formation consists of sediment laid down by the Columbia River following the flood basalt eruptions of the Columbia River Basalt Group, and reaches up to thick in places. It preserves fossils dating back to the late Miocene and Pliocene epochs of the Neogene period.
Exposures of the Ringold Formation can be found from Hanford Reach National Monument north to the Moses Lake area. Large portions of the formation are buried by other sediment deposits, extending as far as Wallula Gap southeast of Kennewick. In recent years, irrigation water entering the groundwater system has destabilized some Ringold Formation slopes and cliffs, causing landslides. The formation was named in 1917 for a school of the same name that existed at the time. Ringold School was located on the Franklin County side of the Columbia River to the south of Savage Island.
Geology During the flood basalt eruptions before the sediments were laid down, the Columbia River followed a different route than it does today, taking it near the present-day sites of Yakima and Goldendale. North-to-south compression of the Columbia Plateau caused anticline folds like Rattlesnake Mountain and the Horse Heaven Hills to rise.
These ridges provided geographic barriers, rerouting the river eastward toward the Tri-Cities with it eventually flowing through Wallula Gap. During part of this period, the Columbia River was completely dammed leading to the development of a large lake covering the Yakima Valley and southern Columbia Basin. The Ringold Formation is the sediment laid down during the period of the lake's existence and while the route of the river was changing.
Some of the sediments found as part of the formation may have been sourced from ancestral versions of other Pacific Northwest rivers like the Clearwater and Pend Oreille. Layers of volcanic ash can also be found, with thicknesses ranging from being barely noticeable to thick.
Stratigraphy The Ringold Formation represents sand and gravel placed by the Columbia River between around 8.5 and 3 million years ago. These deposits overlay cooled lava erupted as part of the Columbia River Basalt Group, a type of volcanic eruption known as flood basalts erupting from fissures across eastern Washington and Oregon that were unrelated to the Cascade Range. It is covered in places by deposits from the Missoula Floods.
Regional uplift caused the Columbia to erode parts of the Ringold Formation. The White Bluffs on Hanford Reach National Monument are a significant example of this.
Recent landslides Landslides along the Columbia River have increased in recent years due to irrigation around Basin City and Othello. Irrigation water enters and flows through the groundwater system toward the river easily through deposits left by the Missoula Floods. This destabilizes Ringold Formation features like the White Bluffs, causing the landslides. Landslides did not occur frequently before 1960. Rapid changes in river flow caused by the Priest Rapids Dam upstream may also contribute to slope destabilization.
The largest landslide in the White Bluffs portion of the formation is adjacent to Locke Island. This complex, initiated in the 1970s, has rerouted the Columbia River. As a result of the change, critical salmon spawning habitat has been destroyed. The landslide restricts the flow of the river on the east side of the river and as a result, large portions of Locke Island are being removed by the Columbia River. Movement of this landslide is ongoing, but the primary factor behind the continued movement is destabilization by the Columbia River eroding the fallen material. Blown sand from this landslide is the primary source material for sand dunes atop the bluffs near the island.
The Locke Island slide is the northernmost slide along the White Bluffs. There are at least five other major slides into the Columbia River, with the southernmost one being across the river from Pacific Northwest National Laboratory in north Richland, which occurred in 2008. At least one slide has occurred in nearby coulees.
Paleobiota
Mammals The mammal fossils of the Ringold Formation are divided into several local faunas, from youngest to oldest:
Taunton local fauna (Blancan III NALMA, chron C2An.1r of the mid-Pliocene, ~3.05 million years old) Blufftop local fauna (Blancan II NALMA, mid-Pliocene, ~4.3 million years old) White Bluffs local fauna (Blancan I NALMA, chrons C3n.3r or C3n.2r of the early Pliocene, 4.98–4.62 million years old) River Road local fauna (late Hemphillian NALMA, latest Miocene or earliest Pliocene)
Artiodactyla Artiodactyls of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImagesAntilocapridaeWhite BluffsIndeterminate pronghorns.† Bretzia† B. pseudalcesWhite BluffsA very common capreoline deer with palmate antlers similar to moose. One of the earliest deer in North America.† Camelops† C. sp.TauntonA large camel.† Capromeryx† C. tauntonensisTauntonAn antilocaprid (pronghorn). Later Capromeryx species were quite small, but this early species was only slightly smaller than living pronghorns.CervidaeBlufftop, TauntonIndeterminate deer. Some Taunton fossils are similar to Odocoileus (mule deer and kin) and Rangifer (reindeer).† Hemiauchenia† H. blancoensisWhite Bluffs, TauntonA common lamine camelid (related to llamas, alpacas, and kin).† Megatylopus† M. sp. aff. M. gigasRiver Road, White BluffsA common large camel, either M. gigas or M. cochrani.† Platygonus† P. pearceiWhite BluffsA common flat-headed peccary.† P. sp.Taunton
Carnivora Carnivorans of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImagesBassariscusB. astutusWhite Bluffs, TauntonThe living ringtail, a species of procyonid (raccoon-like mammals).† Borophagus† B. diversidensTauntonA very large borophagine (bone-crushing dog).† B. hilliWhite Bluffs† Buisnictis† B. cf. breviramusTauntonA skunk.Canis† C. lepophagusTauntonA coyote-like canine.† Chasmaporthetes† C. ossifragusWhite BluffsA long-limbed hyena.† Dinofeliscf. † D. paleooncaTauntonA possible machairodontine (saber-toothed cat).† Eucyon† E. davisiWhite BluffsA coyote-like canine, previously classified as a species of Canis."Felis"F. sp.White Bluffs, TauntonA cougar-sized cat, probably the same as Puma lacustris or "Lynx rexroadensis".cf. † Homotheriumcf. † H. sp.White BluffsA relatively small machairodontine (saber-toothed cat).† Huracan† H. cf. schneideriWhite BluffsA large ailuropodine (panda-like) bear, previously considered a species of Agriotherium. One of the last surviving ailuropodine bears in North America.LynxL. cf. rufusTauntonA possible bobcat.Mustela† M. cf. rexroadensisTauntonA weasel.† Parailurus† P. sp.TauntonA large ailurid (red panda-like mammal).† Plionarctos† P. harroldorumWhite BluffsA tremarctine (short-faced bear) which was probably ancestral to later tremarctines. Fossils of this species were previously identified as Ursus abstrusus or Tremarctos floridanus.† P. cf. harroldorumTaunton† Pliotaxidea† P. sp.White BluffsAn American badger-like mustelid.Procyon?P.? sp.TauntonA possible raccoon.† Satherium† S. piscinariumTauntonAn otter.SpilogaleS. sp.TauntonA spotted skunk.TaxideaT. sp.TauntonAn American badger.† Trigonictis† T. cookiiWhite Bluffs, TauntonAn ictonychine (grison-like mustelid). T. cookii may represent small individuals of T. macrodon.
Lagomorpha Lagomorphs of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImages† Alilepus† A. vagusTauntonA rabbit.† Hypolagus† H. edensisTauntonA rabbit.† H. furlongiTaunton† H. gidleyiTaunton† H. ringoldensisWhite Bluffs, TauntonLeporidaeBlufftopAn indeterminate rabbit or hare.† Nekrolagus† N. progressusWhite BluffsA rabbit.† N.? sp.Taunton
Perissodactyla Perissodactyls of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImages† Aphelops† A. cf. mutilusAn aceratheriine rhinoceros, the oldest mammal in the formation.Equus† Equus francescanaWhite BluffsA zebra-like horse similar to the Hagerman horse. Sometimes classified as Dolichohippus or Plesippus.† Equus simplicidensTauntonA zebra-like Hagerman horse. Sometimes classified as Dolichohippus or Plesippus.TapirusT. sp.White BluffsA tapir.† Teleoceras† T. hicksiRiver Road, White BluffsA teleoceratin aceratheriine rhinoceros.
Pilosa Pilosans of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImages† Megalonyx† M. leptostomusTauntonA megalonychid ground sloth.† M. rohrmanniWhite BluffsA fairly common megalonychid ground sloth.
Proboscidea Proboscideans of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImages† Mammut† M. americanumWhite BluffsThe oldest known fossils of the American mastodon.
Rodentia Rodents of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImagesAmmospermophilus† A. hanfordiWhite BluffsAn antelope squirrel.Castor† C. californicusWhite Bluffs, TauntonA beaver.† Dipoides† D. rexroadensisWhite BluffsA very large beaver.† Mimomys† M. meadensisTauntonA microtine vole. Some fossils of this species were previously known as Ophiomys taylori.† M. sawrockensisWhite BluffsA microtine vole. Some fossils of this species were previously known as Ophiomys mcknighti.† M. sawrockensis-tayloriWhite Bluffs, BlufftopA microtine vole, intermediate between M. sawrockensis and M. taylori. Some fossils of this population were previously known as Ophiomys mcknighti.Neotoma (Paraneotoma)† N. (P.) cf. fossilisTauntonA woodrat.† N. (P.) cf. quadriplicatusWhite Bluffs† Paenemarmota† P. sp.White BluffsA very large marmot.PerognathusP. sp.TauntonA pocket mouse.Peromyscus† P. nosherWhite BluffsA deer mouse.Ondatra (Pliopotamys)† O. (P.) minorTauntonA muskrat.† Procastoroides† P. cf. idahoensisTauntonA beaver.† Prodipodomys† P. sp.TauntonA heteromyid with similarities to Dipodomys (kangaroo rats).Spermophilus† S. cf. howelliTauntonA ground squirrel.† S.? russelliWhite Bluffs† S.? cf. russelliTauntonThomomys† T. cf. gidleyiWhite Bluffs, TauntonA smooth-toothed pocket gopher.
Soricomorpha Soricomorphs of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImages† Paracryptotis† P. rexBlufftopA shrew.ScapanusS. sp.White BluffsA broad-footed mole.Sorex† S. cf. meltoniTauntonA long-tailed shrew.† S. powersiBlufftopS. sp.Taunton
Birds Birds of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImagesAechmophorusA. sp.TauntonA grebe.AnasA. sp.TauntonA teal-like duck.AythyaA. sp.TauntonA scaup-like duck.BrantaB. sp.TauntonA black goose.DendragapusD. sp.TauntonA grouse.FulicaF. sp.TauntonA coot.PodicepsP. sp.TauntonA grebe.
Reptiles Reptiles of the Ringold FormationGenus / TaxonSpeciesLocal faunaNotesImagesCharinaC. bottaeTauntonThe living rubber boa.CheloniaWhite Bluffs, TauntonIndeterminate turtles and tortoises.Chrysemys?C.? sp.White BluffsA painted turtle.ClemmysC. marmorataWhite BluffsThe living Western pond turtle.Coluber / MasticophisC. sp. / M. sp.TauntonA racer or whip snake.CrotalusC. sp.TauntonA rattlesnake.Elaphe† E. pliocenicaTauntonA rat snake.E. vulpinaTauntonThe living Eastern foxsnake.LampropeltisL. getulaTauntonThe living common kingsnake.PituophisP. cateniferTauntonThe living Western gopher snake.SquamataWhite Bluffs, TauntonIndeterminate snakes and lizards.† Tauntonophis† T. morganorumTauntonA colubrine colubrid snake.Testudo / GeocheloneT. sp. / G. sp.White BluffsA tortoise.ThamnophisT. sp.TauntonA garter snake.
Amphibians Indeterminate frog or toad bones are known from the White Bluffs local fauna.
Fish