Klondike Mountain Formation

Last updated
Klondike Mountain Formation
Stratigraphic range: Eocene (Ypresian)
50.1–48.9  Ma
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
↓
Klondike Mountain Formation outcrop - Site A0307.JPG
Klondike Mountain Formation outcrop at site A0307
Type Geological formation
Unit of Okanagan Highlands
Sub-unitsTom Thumb Tuff, Lower & Upper Members
UnderliesGlacial deposits
Overlies Sanpoil Volcanics & others
Thicknessup to 3,200 ft (980 m)
Lithology
PrimaryVariable
Other See text
Location
Coordinates 48°42′N118°42′W / 48.7°N 118.7°W / 48.7; -118.7
Approximate paleocoordinates 54°24′N101°54′W / 54.4°N 101.9°W / 54.4; -101.9
Region Okanagan highlands
CountryFlag of the United States.svg  United States
Extent Okanagan highlands
Type section
Named for Klondike Mountain
Named byMuessig
Year defined1962
Usa edcp relief location map.png
Orange pog.svg
Klondike Mountain Formation (the United States)
USA Washington relief location map.jpg
Orange pog.svg
Klondike Mountain Formation (Washington (state))

The Klondike Mountain Formation is an Early Eocene (Ypresian) geological formation located in the northeast central area of Washington state. The formation is comprised of volcanic rocks in the upper unit and volcanic plus lacustrine (lakebed) sedimentation in the lower unit. the formation is named for the type location designated in 1962, Klondike Mountain northeast of Republic, Washington. The formation is a lagerstätte with exceptionally well-preserved plant and insect fossils has been found, along with fossil epithermal hot springs.

Contents

The Klondike Mountain formation is the youngest in a series of formations which belong to the Challis Sequence volcanics, and is the southernmost of the Eocene Okanagan Highlands paleolake lagerstätten. The formation unconformably overlies rocks of the Eocene Sanpoil Volcanics and much older Triassic and Permian formations. The formation is bounded on its edges by a series of high-angle strike slip faults, which have contained the Klondike Mountain Formation in a series of graben structures, such as the Republic Graben. Public access to a fossiliferous outcrop at the north end of Republic is mediated by the nonprofit Stonerose Interpretive Center.

Extent

The formation is located in northern Ferry County, Washington, with the majority of the sedimentation in the Republic and Curlew Basins on the east and in the Toroda Creek area to the north west. The town of Republic, Washington is situated at the southern end of the formation, with outcrops within the city itself. The formation was named for Klondike Mountain which is just to the northeast of the city, and where the type locality is located. [1] The Curlew basin is situated north of Republic, with the northern edge along the Kettle River and the community of Curlew, Washington near the northeastern edge. [2] [3]

The formation is the southernmost of in the string of Eocene highland lakebeds that extend into British Columbia. [4] The lake system, overlapping the modern Okanagan highlands, extends from the Klondike Mountain Formation northwest approximately 1,000 kilometres (1,000,000 m) in to central British Columbia. [5] Closely correlated with and possibly representing the same lake sequence as the Klondike Mountain Formation are the Penticton Group's Kettle River, Marama and Marron Formations in the Boundary District along the Canada-United States border. [6]

Age

Early dating of the formation was based primarily on identification and correlation of the fossils found in the Tom Thumb Tuff, with Joseph Umpleby (1910) reporting a putative age of Early Miocene. [7] This date was based in examination of fossils by C. R. Eastman, who thought them to be similar to those found in the Florissant Formation of Colorado, which at the time was also considered Miocene. This age was retained by Edward W. Berry (1929), who included the Klondike Mountain Formation fossil lakebeds as part of the Latah Formation. [8] The age of the Formation has been revised in the following hundred years, with Roland W. Brown (1936) identifying the deposits as being older than the Latah Formation. [9] In a later written communication circa 1958, Brown again revised the age still older, stating the fossils found in the area of Mount Elizabeth indicated an Oligocene age. This age was used by Parker and Calkins (1964) for work on the Curlew Quadrangle of Ferry County. [10] Work by Pearson and Obradovich (1977) refined the Sanpoil Volcanics age to around 52 to 51 million years ago, and a general age estimate for the Klondike Mountain Formation between 50.3  ± 1.7 million years ago and 42.3  ± 2.0 million years ago. [11] Since then the fossil-bearing strata of the Formation have been radiometrically dated, to give an estimate of the Ypresian, the mid stage of the early Eocene, 49.4  ± .5 million years ago, [5] which was revised to an oldest age estimate of 51.2  ± 0.1 million years ago which given based on detrital zircon isotopic data published in 2021. [12]

Lithology

Parker and Calkins (1964) noted the association of the Klondike Mountain Formation with the gold and silver deposits of the Republic District and suggested it as a potential host to more ore deposits in the Curlew Quadrangle. [10] The epithermal gold deposits occurring in the Sanpoil volcanics terminate directly below the unconformity where the volcanics contact the base of the Klondike Mountain Formation [13] or sometimes penetrate into the Formation's lowest unit. [14] Hydrothermal sinter deposits are known from the lowest portions of the Formation and are thought to represent hydrothermal eruption areas. [14] In general the lower portions of the Formation have a large amount of hydrothermal alteration, and areas around vents are rich in pyrite and silica. two products of natural hydrothermic sintering. The areas above that show a transition to mudstones, siltstones and sandstones grading from fine-grained material into coarser materials moving up the strata column. The finely-bedded stones show the greatest numbers of fossils and the finest preservation of details. [15]

Paleoenvironment and paleoclimate

The lake bed sediments preserve a diverse array of plants, insects, and fishes, notably the biota called the Republic flora. [16] The Okanagan lake system, which includes the Klondike Mountain Formation, has been classified as one of the great Canadian lagerstätten. [17] The area likely had a mesic upper microthermal to lower mesothermal climate, in which winter temperatures rarely dropped low enough for snow, and which were seasonably equitable. [18]

The Okanagan highlands paleoforest surrounding the lakes have been described as precursors to the modern Temperate broadleaf and mixed forests of Eastern North America and Eastern Asia. Based on the fossil biotas the lakes were higher and cooler then the coeval coastal forests preserved in the Puget Group and Chuckanut Formation of Western Washington, which are described as lowland tropical forest ecosystems. Estimates of the paleoelevation between 0.7 and 1.2 km (0.43 and 0.75 mi) higher than the coastal forests. This is consistent with the paleoelevation estimates for the lake systems, which range between 1.1 and 2.9 km (1,100 and 2,900 m), which is similar to the modern elevation 0.8 km (0.50 mi), but higher. [18]

Estimates of the mean annual temperature have been derived from Climate leaf analysis multivariate program (CLAMP) and leaf margin analysis (LMA) of the Republic paleoflora. The CLAMP results after multiple linear regressions for Republic gave a mean annual temperature of approximately 8.0 °C (46.4 °F), while the LMA gave 9.2 ± 2.0 °C (48.6 ± 3.6 °F). This is lower than the mean annual temperature estimates given for the coastal Puget Group, which is estimated to have been between 15 and 18.6 °C (59.0 and 65.5 °F). The bioclimatic analysis for Republic suggests a mean annual precipitation amount of 115 ± 39 cm (45 ± 15 in). [18]

Paleobiota

The Klondike Mountain Formation is host to a highly diverse assemblage of plants and insects including some of the last records of taxa before extinction and the first appearances of taxa.


Related Research Articles

<i>Tilia johnsoni</i> Extinct species of flowering plant

Tilia johnsoni is an extinct species of flowering plant in the family Malvaceae that, as a member of the genus Tilia, is related to modern lindens. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States and a similar aged formation in British Columbia, Canada.

<i>Sassafras hesperia</i> Extinct species of flowering plant

Sassafras hesperia is an extinct species of flowering plant in the family Lauraceae.

<i>Hiodon woodruffi</i> Extinct species of fish

Hiodon woodruffi is an extinct species of bony fish in the mooneye family, Hiodontidae. The species is known from fossils found in the early Eocene deposits of northern Washington state in the United States and late Eocene deposits in northwestern Montana. The species was first described as Eohiodon woodruffi. H. woodruffi is one of two Eocene Okanagan Highlands mooneye species, and one of five fish identified in the Klondike Mountain Formation.

<i>Pinus latahensis</i> Extinct species of conifer

Pinus latahensis is an extinct species of conifer in the pine family Pinaceae. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States, and southern British Columbia, Canada.

<i>Pseudolarix wehrii</i> Extinct species of conifer

Pseudolarix wehrii is an extinct species of golden larch in the pine family (Pinaceae). The species is known from early Eocene fossils of northern Washington state, United States, and southern British Columbia, Canada, along with late Eocene mummified fossils found in the Qikiqtaaluk Region, Nunavut, Canada.

<i>Comptonia columbiana</i> Extinct species of sweet fern

Comptonia columbiana is an extinct species of sweet fern in the flowering plant family Myricaceae. The species is known from fossil leaves found in the early Eocene deposits of central to southern British Columbia, Canada, plus northern Washington state, United States, and, tentatively, the late Eocene of Southern Idaho and Earliest Oligocene of Oregon, United States.

<i>Amia</i>? <i>hesperia</i> Extinct species of ray-finned fishes

Amia? hesperia is an extinct species of bony fish in the bowfin family, Amiidae. The species is known from fossils found in the early Eocene deposits of northern Washington state in the United States and southeastern British Columbia. The species is one of eight fish species identified in the Eocene Okanagan Highlands paleofauna.

<i>Barghoornia</i> Extinct species of flowering plants

Barghoornia is an extinct genus of flowering plants in the family Burseraceae containing the solitary species Barghoornia oblongifolia. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States.

Acer spitzi is an extinct maple species in the family Sapindaceae described from a single fossil samara. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States. It is the only species belonging to the extinct section Spitza.

<i>Carpinus perryae</i> Extinct species of hornbeam

Carpinus perryae is an extinct species of hornbeam known from fossil fruits found in the Klondike Mountain Formation deposits of northern Washington state, dated to the early Eocene Ypresian stage. Based on described features, C. perryae is the oldest definite species in the genus Carpinus.

Klondikia is an extinct hymenopteran genus in the ant family Formicidae with a single described species Klondikia whiteae. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States. The genus is currently not placed into any ant subfamily, being treated as incertae sedis.

<i>Pteronepelys</i> Fossil genus of plants

Pteronepelys, sometimes known as the winged stranger, is an extinct genus of flowering plant of uncertain affinities, which contains the one species, Pteronepelys wehrii. It is known from isolated fossil seeds found in middle Eocene sediments exposed in north central Oregon and Ypresian-age fossils found in Washington, US.

<i>Fagus langevinii</i> Fossil species of beech tree

Fagus langevinii is an extinct species of beech in the family Fagaceae. The species is known from fossil fruits, nuts, pollen, and leaves found in the early Eocene deposits of South central British Columbia, and northern Washington state, United States.

<span class="mw-page-title-main">Eocene Okanagan Highlands</span>

The Eocene Okanagan Highlands or Eocene Okanogan Highlands are a series of Early Eocene geological formations which span a 1,000 km (620 mi) transect of British Columbia, Canada, and Washington state, United States. Known for a highly diverse and detailed plant and animal paleobiota the paleolake beds as a whole are considered one of the great Canadian Lagerstätten. The paleobiota represented are of an upland subtropical to temperate ecosystem series immediately after the Paleocene–Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1870–1920s on British Columbian sites, and 1920–1930s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highland sites started in the late 1960s.

Uhlia is an extinct genus of coryphoid palm containing a single species Uhlia allenbyensis. The species is known from permineralized remains recovered from the Princeton Chert in British Columbia, Canada. Leaves of Uhlia have "tar spot"-like fungal infections of the extinct ascomycete Paleoserenomyces, which in turn are hyperparasitized by the ascomycete Cryptodidymosphaerites.

Paleoserenomyces is an extinct monotypic genus of pleosporale fungus of uncertain family placement. When described it contained the single species Paleoserenomyces allenbyensis. The genus is solely known from the Early Eocene, Ypresian aged, Princeton Chert deposit of the Allenby Formation. Palaeoserenomyces is one of only three described fossil fungus species found in the Princeton Chert, being a tar spot like parasite of the fossil palm Uhlia allenbyensis, and is host for the hyperparasite Cryptodidymosphaerites princetonensis.

Cryptodidymosphaerites is an extinct monotypic genus of pleosporale fungus of uncertain family placement. When described it contained the single species Cryptodidymosphaerites princetonensis. The genus is solely known from the Early Eocene, Ypresian aged, Princeton Chert deposit of the Allenby Formation. Cryptodidymosphaerites is one of only three described fossil fungus species found in the Princeton Chert, and is a hyperparasite of Palaeoserenomyces allenbyensis, itself a tar spot-like parasite of the fossil palm Uhlia.

<i>Promastax</i> Extinct genus of insects

Promastax is a genus of "monkey grasshoppers" belonging to the extinct monotypic family Promastacidae and containing the single species Promastax archaicus. The species is dated to the Early Eocenes Ypresian stage and has only been found at the type locality in east central British Columbia.

<i>Alnus parvifolia</i> Extinct species of flowering plant

Alnus parvifolia is an extinct species of flowering plant in the family Betulaceae related to the modern birches. The species is known from fossil leaves and possible fruits found in early Eocene sites of northern Washington state, United States, and central British Columbia, Canada.

<i>Republicopteron</i> Genus of cricket-like animals

Republicopteron is an extinct orthopteran genus in the katydid-like family Palaeorehniidae with a single described species, Republicopteron douseae.

References

  1. ↑ Muessig, Siegfried (1962). "Tertiary volcanic and related rocks of the Republic area, Ferry County, Washington". Geological Survey Research 1962. 450 D: D56–58.
  2. ↑ Gaylord, DR; Suydam, JD; Price, SM; Matthews, JM; Lindsey, KA (1996). "Depositional history of the uppermost Sanpoil Volcanics and Klondike Mountain Formation in the Republic basin". Washington Geology. 24 (2): 15–18.
  3. ↑ Cheney, ES; Rasmussen, MG (1996). "Regional geology of the Republic area". Washington Geology. 24 (2): 3–7.
  4. ↑ Suydam, J.; Gaylord, D.R. (1997). "Toroda Creek half graben, northeast Washington: Late-stage sedimentary infilling of a synextensional basin". Geological Society of America Bulletin. 109 (10): 1333–1348. Bibcode:1997GSAB..109.1333S. doi:10.1130/0016-7606(1997)109<1333:tchgnw>2.3.co;2.
  5. 1 2 Makarkin, V.; Archibald, S.B. (2014). "An unusual new fossil genus probably belonging to the Psychopsidae (Neuroptera) from the Eocene Okanagan Highlands, western North America". Zootaxa. 3838 (3): 385–391. CiteSeerX   10.1.1.692.1185 . doi:10.11646/zootaxa.3838.3.8. PMID   25081783.
  6. ↑ Höy, T.; Friedman, R.; Gabites, J. Paleogene Penticton Group, Boundary area, Southern British Columbia (Parts of NTS 082E): Geochronology and Implications for Precious Metal Mineralization (PDF) (Report). Geoscience BC Summary of Activities 2020: Minerals, Geoscience BC, Report 2021-01. Geoscience BC. pp. 55–66.
  7. ↑ Umpleby, J. B. (1910). "Geology and ore deposits of Republic mining district". Washington Geological Survey. 1.
  8. ↑ Berry, E.W. (1929). A revision of the flora of the Latah Formation (Report). Professional Paper. United States Geological Survey. pp. 225–265. doi: 10.3133/pp154h . 154-H.
  9. ↑ Brown, R. W. (1937). Additions to some fossil floras of the Western United States (PDF) (Report). Professional Paper. Vol. 186. United States Geological Survey. pp. 163–206. doi:10.3133/pp186J.
  10. 1 2 Parker, RL; Calkins, JA (1964). "Geology of the Curlew Quadrangle, Ferry County, Washington". Geological Survey Bulletin. 1169.
  11. ↑ Wolfe, J.; Wehr, W. (1991). "Significance of the Eocene fossil plants at Republic, Washington" (PDF). Washington Geology. 19 (3): 18–24.
  12. ↑ Rubino, E.; Leier, A.; Cassel, E.; Archibald, S.; Foster-Baril, Z.; Barbeau, D. Jr (2021). "Detrital zircon UPb ages and Hf-isotopes from Eocene intermontane basin deposits of the southern Canadian Cordillera". Sedimentary Geology. 105969 (online).
  13. ↑ Boleneus, DE; Raines, GL; Causey, JD; Bookstrom, AA; Frost, TP; Hyndman, PC (2001). "Assessment method for epithermal gold deposits in northeast Washington State using weights-of-evidence GIS modeling" (PDF). USGA Open File Report. 01–501: 1–52.
  14. 1 2 Lasmanis, R (1996). "A historical perspective on ore formation concepts, Republic Mining District, Ferry County, Washington". Washington Geology. 24 (2): 8–11.
  15. ↑ Gaylord, DR; Price, SM; Suydam, JD (2001). Volcanic and hydrothermal influences on middle Eocene lacustrine sedimentary deposits. Republic Basin, northern Washington, USA. pp. 199–222. ISBN   9781444304268.{{cite book}}: |journal= ignored (help)
  16. ↑ Wolfe, J.A.; Wehr, W.C. (1987). Middle Eocene dicotyledonous plants from Republic, northeastern Washington (Report). Bulletin. Vol. 1597. United States Geological Survey. pp. 1–25. doi: 10.3133/b1597 .
  17. ↑ Archibald, S.; Greenwood, D.; Smith, R.; Mathewes, R.; Basinger, J. (2011). "Great Canadian Lagerstätten 1. Early Eocene Lagerstätten of the Okanagan Highlands (British Columbia and Washington State)". Geoscience Canada. 38 (4): 155–164.
  18. 1 2 3 Greenwood, D.R.; Archibald, S.B.; Mathewes, R.W; Moss, P.T. (2005). "Fossil biotas from the Okanagan Highlands, southern British Columbia and northeastern Washington State: climates and ecosystems across an Eocene landscape". Canadian Journal of Earth Sciences. 42 (2): 167–185. Bibcode:2005CaJES..42..167G. doi:10.1139/e04-100.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.