Origin of apatite-dominated rock penetrating the volcaniclastic fill of the Pleistocene Bažina maar (western Czech Republic)

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F24%3A00599284" target="_blank" >RIV/67985530:_____/24:00599284 - isvavai.cz</a>

Alternative codes found

RIV/00025798:_____/24:10169059 RIV/00216208:11310/24:10487503

Result on the web

<a href="http://www.jgeosci.org/detail/jgeosci.392" target="_blank" >http://www.jgeosci.org/detail/jgeosci.392</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3190/jgeosci.392" target="_blank" >10.3190/jgeosci.392</a>

Result language

angličtina

Original language name

Origin of apatite-dominated rock penetrating the volcaniclastic fill of the Pleistocene Bažina maar (western Czech Republic)

Original language description

The sequence of alkaline basaltic lavas and associated pyroclastic deposits that fill Bažina maar in western Bohemia is transected by a vein of apatite-dominated rock revealed in the S4 borehole. Aside from solid vein fill, apatite also impregnates a significant part of the drilled volcanic sequence. In the main body (depth 60.00-66.60 m), apatite occurs in two texturally distinct types: common cauliflower-type apatite (type 1) is transected by veinlets of coarser (0.2 mm long) apatite crystals (type 2). Both types have grown into open spaces suggesting precipitation from fluids rather than crystallization from melt, which is consistent with generally low trace element contents with slight enrichment in Cs, Sr, U and Pb. Relative to other local Plio-Pleistocene volcanic rocks, apatite vein-fill is shifted in Sr-87/Sr-86 towards more radiogenic values (0.7053-0.7054). This suggests that fluids carrying mantle-derived ions mixed with groundwater interacting with granitic country-rock, as also evidenced by the purely crustal character of noble gases trapped in apatite. Unlike the mofettes occurring along the Mariánské Lázně Fault on the eastern margin of the Cheb Basin, the He-4/He-3 ratios from Bažina apatite do not indicate mantle noble gas contribution. According to our model, the originally Sr-P-rich fluids with low Sr-87/Sr-86 mixed with Cs-U-enriched groundwater circulating in country-rock granites with radiogenic Sr-87/Sr-86. Therefore, present-day CO2 outgassing through mofettes related mainly to the Mariánské Lázně Fault (eastern margin of the Cheb Basin) is likely independent of, and unrelated to, volcanism of the Cheb–Domažlice Graben.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10507 - Volcanology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geosciences

ISSN

1802-6222

e-ISSN

1803-1943

Volume of the periodical

69

Issue of the periodical within the volume

2

Country of publishing house

CZ - CZECH REPUBLIC

Number of pages

15

Pages from-to

113-127

UT code for WoS article

001298823300004

EID of the result in the Scopus database

2-s2.0-85202567467