Klastline Formation

Unit Name: Klastline Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Pleistocene - Holocene (1.806 - 0 ma)
Age Justification: Geochronology. A sample from one of the large remnants in Klastline Valley yielded a date of 0.62 ± 0.04 Ma, which is consistent with its stratigraphic position between the Edziza (0.9 Ma) and Kakiddi (0.3 Ma) formations (Souther et al., 1984).
Province/Territory: British Columbia

Originator: Souther et al., 1984.

Distribution:

North slope of Mount Edziza (Souther, 1988). Remnants of the thick basalt flows are preserved south of Buckley Lake, along the western side of Kakiddi Valley, and as small buttes and buttresses along Klastline Valley. They occur as isolated, usually flat-topped erosional remnants bounded by low escarpments from 6-12 m high (Souther, 1992).

Lithology:

The Klastline flows are highly porphyritic alkali olivine basalts with abundant phenocrysts of calcic plagioclase, titanaugite, and olivine in a groundmass of the same minerals plus disseminated opaques and minor glass (Souther et al., 1984).

Age Determinations:

Method - K/Ar; Material - Whole Rock; Age - 0.62; Err_Minus - 0.04; Err_Plus - 0.04..

Relationship:

The Klastline Formation is a unit of the Mount Edziza Complex. Its lower contact with the Edziza Formation is mostly conformable, but also locally disconformable. The upper contact with the Big Raven Formation is disconformable (Souther, 1988).

Other Citations:

Mihalynuk et al., 1996.

References:

Mihalynuk, M., Bellefontaine, K., Brown, D., Logan, J., Nelson, J., Legun, A. and Diakow, L., 1996. Digital Geology, NW British Columbia (94/E, L, M; 104/F, G, H, I, J, K, L, M, N, O, P; 114/I, O, P); Ministry of Energy, Mines and Petroleum Resources, Open File 1996-11.

Souther, J.G., 1988. Geology, Mount Edziza volcanic complex, British Columbia; Geological Survey of Canada, "A" Series Map no. 1623A, 2 sheets.

Souther, J.G., 1992. The Late Cenozoic Mount Edziza Volcanic Complex, British Columbia; Geological Survey of Canada, Memoir 420, 329 p.

Souther, J.G., Armstrong, R.L., and Harakal, J., 1984. Chronology of the peralkaline, late Cenozoic Mount Edziza Volcanic Complex, northern British Columbia, Canada; Geological Society of America Bulletin, March 1984, Vol. 95, Issue 3, pp. 337-349.

Source: LEXICON_BC
Contributor: Michael Pashulka
Entry Reviewed: No
Name Set: Lithostratigraphic Lexicon
LastChange: 03 Feb 2011