Apatite fission-track age-spectrum based on projected track-length analysis

AbstractA fission track study has been carried out on apatite from the igneous rock belt running along the southern border of the Brabant Massif. The study includes age determinations and a length analysis of both surface tracks and confined tracks. Apatite fission track ages vary between 146 Ma and 209 Ma. Confined track length distributions and the projected length age spectra indicate that the rocks cooled relatively rapidly from above 100 °C to ambient temperatures. The fission track ages therefore date a cooling phase of the Brabant Massif which is interpreted as reflecting an important uplift during the major part of the Jurassic, related to the Cimmerian tectonism which affected the North Sea basin and adjacent areas. Two apatite samples from the southerly Dinant Basin yield fission track ages around 200 Ma, similar to the oldest ages observed in the Brabant Massif, and with comparable track length characteristics. This indicates that the uplift was not limited to the Brabant region but also affected the Hercynian basement to the south.

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Apatite fission-track age correction and thermal history analysis from projected track length distributions

Chemical Geology ◽

10.1016/0009-2541(93)90298-w ◽

1993 ◽

Vol 103 (1-4) ◽

pp. 157-169

Author(s):

M. Grivet ◽

M. Rebetez ◽

N. Ben Ghouma ◽

A. Chambaudet ◽

R. Jonckheere ◽

...

Keyword(s):

Thermal History ◽

Fission Track ◽

Track Length ◽

Apatite Fission Track ◽

History Analysis ◽

Age Correction

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Reproducibility of apatite fission-track length data and thermal history reconstruction

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2009.05.015 ◽

2009 ◽

Vol 284 (3-4) ◽

pp. 504-515 ◽

Cited By ~ 88

Author(s):

Richard A. Ketcham ◽

Raymond A. Donelick ◽

Maria Laura Balestrieri ◽

Massimiliano Zattin

Keyword(s):

Thermal History ◽

Fission Track ◽

Track Length ◽

Apatite Fission Track ◽

Length Data

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Thermochronologic constraints on ore formation at the Gays River Pb–Zn deposit, Nova Scotia, Canada, from apatite fission track analysis

Canadian Journal of Earth Sciences ◽

10.1139/e90-105 ◽

1990 ◽

Vol 27 (8) ◽

pp. 1013-1022 ◽

Cited By ~ 12

Author(s):

Dennis C. Arne ◽

Ian R. Duddy ◽

Don F. Sangster

Keyword(s):

Nova Scotia ◽

Fission Track ◽

Track Length ◽

Late Paleozoic ◽

Apatite Fission Track ◽

Ore Formation ◽

Sulphide Mineralization ◽

Fission Track Ages ◽

Uplift And Erosion ◽

Host Rocks

Fission tracks in detrital apatites from the Cambro-Ordovician metasedimentary basement in the vicinity of the Carboniferous-hosted Gays River Pb–Zn deposit, Nova Scotia, provide a record of final cooling during uplift and erosion of the Meguma Zone and constrain the timing of ore formation. Apatite fission track ages range from 203 to 241 Ma, with typical uncertainties of ± 10 Ma. Mean confined track lengths generally vary between 12.0 and 13.4 μm and indicate that the apatites record "apparent" ages only. An inferred thermal history involving regional heating to paleotemperatures > 110 °C during late Paleozoic burial followed by cooling to ~ 110 °C prior to 240–220 Ma is suggested. A more recent phase or regional heating to paleotem-peratures probably in the range of 60–80 °C during Late Cretaceous – early Tertiary (ca. 100–50 Ma) burial is also indicated by the track length data. Apatite fission track ages and mean track lengths from drill-core samples immediately beneath the Gays River orebody are similar to those for regional outcrop samples. At minimum temperatures > 200 °C estimated for ore formation, sulphide mineralization must either have preceded or accompanied regional heating to paleotemperatures > 110 °C during the late Paleozoic. Sulphide mineralization at Gays River must therefore have taken place at some time after ca. 330 Ma (the stratigraphic age of the lower Windsor Group host rocks) but before ca. 240–220 Ma (the last cooling of Meguma Group basement below 110 °C). These constraints on the timing of ore formation at Gays River are compatible with previous suggestions that Pb–Zn mineralization of Carboniferous strata in Nova Scotia occurred at ca. 300 Ma.

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Burial and exhumation of the Long Range Inlier and its surroundings, western Newfoundland: results of an apatite fission-track study

Canadian Journal of Earth Sciences ◽

10.1139/e93-137 ◽

1993 ◽

Vol 30 (8) ◽

pp. 1594-1606 ◽

Cited By ~ 12

Author(s):

M. Hendriks ◽

R. A. Jamieson ◽

S. D. Willett ◽

M. Zentilli

Keyword(s):

Long Range ◽

Fission Track ◽

Sedimentary Cover ◽

Early Carboniferous ◽

Track Length ◽

Lake Basin ◽

Apatite Fission Track ◽

Slow Cooling ◽

Base Level ◽

Thermal Histories

The Long Range Inlier, a steep-sided plateau underlain mainly by Grenvillian gneisses, is the most prominent topographic feature of western Newfoundland. Apatite fission-track analysis of 31 samples from the Long Range Inlier and its surroundings yielded measured apparent ages of 343–152 Ma. Age versus elevation plots, track-length distributions, and model thermal histories indicate that the region experienced slow cooling in the late Paleozoic, with apparent exhumation rates of 7–9 m∙Ma−1 and cooling rates of 0.08–0.28 °C∙Ma−1. Model thermal histories suggest that the present upper surface of the Long Range plateau cooled below ~120 °C in Ordovician times. The thermal histories are compatible with, but do not require, some exhumation of the Long Range Inlier along Acadian thrust faults. Results from Early Carboniferous sedimentary rocks of the Deer Lake Basin are similar to Long Range Inlier data from similar elevations, implying that at some time between ~350 and 300 Ma, the entire region was buried to depths sufficient to induce total annealing (T > 120 °C) in these samples. Closure ages determined from model thermal histories indicate that regional cooling to temperatures below ~120 °C began before 300 Ma. The Carboniferous sedimentary cover was largely removed by Jurassic time, perhaps in response to lowering of regional base level by rifting associated with the opening of the Atlantic Ocean.

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Further investigation of the initial fission-track length and geometry factor in apatite fission-track thermochronology

American Mineralogist ◽

10.2138/am.2013.4140 ◽

2013 ◽

Vol 98 (8-9) ◽

pp. 1381-1392 ◽

Cited By ~ 8

Author(s):

C. J. Soares ◽

S. Guedes ◽

C. A. Tello ◽

A. L. Lixandrao Filho ◽

A. M. Osorio ◽

...

Keyword(s):

Fission Track ◽

Track Length ◽

Apatite Fission Track ◽

Geometry Factor ◽

Fission Track Thermochronology

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Post-Variscan thermal history of the Intra-Sudetic Basin (Sudetes, Bohemian Massif) based on apatite fission track analysis

International Journal of Earth Sciences ◽

10.1007/s00531-019-01777-9 ◽

2019 ◽

Vol 108 (8) ◽

pp. 2561-2576 ◽

Cited By ~ 2

Author(s):

Dariusz Botor ◽

Aneta A. Anczkiewicz ◽

Stanisław Mazur ◽

Tomasz Siwecki

Keyword(s):

Standard Deviation ◽

Late Cretaceous ◽

Bohemian Massif ◽

Fission Track ◽

Thermal Evolution ◽

Vitrinite Reflectance ◽

Length Distribution ◽

Track Length ◽

Second Phase ◽

Apatite Fission Track

Abstract The Intra-Sudetic Basin, a ~ 12 km deep Variscan intramontane basin, has the best preserved post-orogenic sedimentary record available at the NE margin of the Bohemian Massif. Apatite fission track (AFT) analyses have been performed on 16 sedimentary and volcanic samples of Carboniferous to Cretaceous age from the Intra-Sudetic Basin to improve understanding of the post-Variscan thermal evolution. AFT central ages range from 50.1 ± 8.8 to 89.1 ± 7.1 Ma (Early Eocene to Coniacian), with 13 of them being Late Cretaceous. The mean track length values range from 12.5 ± 0.4 to 13.8 ± 0.5 (except for one sample 14.4 ± 0.2) µm. This relatively short mean track length together with the unimodal track length distributions and rather low standard deviation (0.8 to 1.7 µm) in most samples indicate a long stay in the partial annealing zone during slow cooling. However, in the northern part of the Intra-Sudetic Basin, samples show a wider track length distribution (standard deviation of 1.8 to 2.1 µm) that could indicate a more complex thermal evolution possibly related to Mesozoic reheating. Vitrinite reflectance data combined with thermal models based on the AFT results indicate that the Carboniferous strata reached maximum palaeotemperatures in the latest Carboniferous to Early Permian time, corresponding to a major coalification event. The second phase of temperature rise occurred due to Late Mesozoic sedimentary burial, but it had no influence on maturation of the Carboniferous organic matter. Final cooling phase in the Late Cretaceous–Paleogene was related to tectonic inversion of the Intra-Sudetic Basin, which occurred after deposition of a significant thickness of Cenomanian–Turonian sediments. Thermal modelling demonstrates that ~ 4 km thick cover of Upper Cretaceous sediments is required to obtain a good match between our AFT data and modelled time–temperature paths. This outcome supports a significant amount of Late Cretaceous–Paleogene inversion within the Variscan belt of Central Europe.

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The role of crystallographic angle in characterizing and modeling apatite fission-track length data

Radiation Measurements ◽

10.1016/j.radmeas.2004.07.008 ◽

2005 ◽

Vol 39 (6) ◽

pp. 595-601 ◽

Cited By ~ 19

Author(s):

Richard A. Ketcham

Keyword(s):

Fission Track ◽

Track Length ◽

Apatite Fission Track ◽

Length Data

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New Apatite Fission-Track Data from the Murmansk Craton, NE Fennoscandia: An Echo of Hidden Thermotectonic Events

Minerals ◽

10.3390/min10121095 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1095

Author(s):

Roman V. Veselovskiy ◽

Róbert Arató ◽

Tanya E. Bagdasaryan ◽

Alexander V. Samsonov ◽

Alexandra V. Stepanova ◽

...

Keyword(s):

Kola Peninsula ◽

Fission Track ◽

Thermal Evolution ◽

Age Distribution ◽

Track Length ◽

Temperature History ◽

Thermal Resistivity ◽

Apatite Fission Track ◽

Thermal Event ◽

History Of

For a long time, the thermal history of northeastern (NE) Fennoscandia in the Phanerozoic and Precambrian remained unknown, since no thermochronological studies were carried out within the Kola Peninsula area. Two years ago, we developed the first model of tectono-thermal evolution of the Kola Peninsula territory for the last 1.9 Gyr using a set of newly obtained apatite fission-track (AFT) and Ar/Ar thermochronological data. However, the low-temperature history of the most ancient tectonic unit of the northeastern part of the Kola Peninsula—the Archean Murmansk craton—remained poorly constrained due to the lack of AFT data. In this paper, we present the first results of AFT studies of 14 samples representing intrusive and metamorphic Precambrian rocks, located within the Murmansk craton of NE Fennoscandia. AFT ages and track length distributions indicate a similar tectono-thermal evolution of Precambrian tectonic units in NE Fennoscandia over the last 300 Myr. The AFT ages are distributed between ca. 177 and ca. 384 Ma; their median value, ~293 Ma, confirms the presence of a previously identified hidden thermal event that took place at about 300 Ma. However, a detailed analysis of the AFT age distribution shows the presence of three statistically distinguishable age components: 180–190 Ma (C1), 290–320 Ma (C2) and 422 Ma (C3). We assume that the relatively young AFT ages of C1 may originate from apatite crystals with low thermal resistivity. Remarkably, this value coincides with the initial stage of the Barents Sea magmatic province activity during large-scale plume-lithospheric interaction, as well as with the assumed age of an enigmatic remagnetization event throughout the Kola Peninsula. C2 ages can be observed in both the gabbroic and non-gabbroic samples, whereas C3 ages can only be found in gabbro. It is supposed that C2 ages, similarly to the Central Kola terrane, correspond to a cooling event related to the denudation of a thick sedimentary cover, representing a continuation of the Caledonian foreland basin towards NE Fennoscandia. C3 ages may be associated with a thermal event corresponding to the Caledonian collisional orogeny.

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Thermal history modelling of the western margin of the Bohemian Massif using high-resolution apatite fission-track thermochronology

10.5194/egusphere-egu2020-15152 ◽

2020 ◽

Author(s):

Lucie Novakova ◽

Raymond Jonckheere ◽

Bastian Wauschkuhn ◽

Lothar Ratchbacher

Keyword(s):

High Resolution ◽

Bohemian Massif ◽

Thermal History ◽

Fission Track ◽

Track Length ◽

Apatite Fission Track ◽

Fission Track Thermochronology ◽

Length Measurements ◽

Thermal Histories ◽

Fission Track Ages

The Naab area is situated on the western border of the Bohemian Massif, 60 km south of the KTB (Kontinentalen Tiefbohrung). The main super-deep borehole of the KTB reached a depth of 9,101 meters in the Earth's continental crust. The fission-track data for the KTB and the Naab area present contrasting signatures. The apatite fission-track ages in the upper section of the KTB borehole and surrounding area are in the range 50-70 Ma (Wagner et al., 1994; Wauschkuhn et al., 2015). The apatite fission-track ages of the Naab basement are older than those of the KTB area, and span a broader range: 120-200 Ma (Vercoutere, 1994). The distributions of the confined-track lengths range from unimodal over skewed and mixed to bimodal, with mean lengths in the range 11-13 &#181;m. In broad terms, this can be interpreted as that the Naab samples contain both an older and younger (in particular pre- and post-late Cretaceous) fission-track population. The aim of our research is to investigate the applicability of lab-based models to geological data, using improved measurement techniques.We studied eighteen samples dated by Vercoutere (1994) from the Palaeozoic basement and seven large rock samples from the Rotliegend strata north of the Luhe fault.&#160; We intend to extend the confined-track length measurements of Vercoutere (1994), aiming to achieve higher resolution through methodological innovations made possible by computer-controlled motorized microscopes. Improved statistics increase the resolution of the modelled thermal histories, which permits to better distinguish systematic from statistical differences between the modelled palaeotemperatures and geological estimates. Experiments have shown that the rate of length increase permits to distinguish older from younger tracks (Jonckheere et al., 2017). This allows us to distinguish between tracks formed before and after the Late Cre&#173;taceous to Palaeocene exhumation. The etch rate of a confined track is also an indicator of its individual thermal history, supplementing the information gleaned from its etchable length under fixed conditions. We compiled a comprehensive, high-resolution confined-track-length dataset. The Naab thermal histories were determined using modern modelling algorithms, implementing the most recent empirical equations.ReferencesJonckheere R., Tamer M., Wauschkuhn F., Wauschkuhn B., Ratschbacher L., 2017. Single-track length measurements of step-etched fission tracks in Durango apatite: Vorsprung durch Technik.American Mineralogist 102, 987-996.Vercoutere C., 1994. The thermotectonic history of the Brabant Massif (Belgium) and the Naab Basement (Germany): &#160;&#160;an apatite fission track analysis. Ph. D. thesis, Universiteit Gent, pp. 191.Wagner G.A., Hejl E., Van Den Haute P., 1994. The KTB fission-track project: Methodical aspects and geological implications. Radiation Measurements 23, 95-101.Wauschkuhn B., Jonckheere R., Ratschbacher L., 2015. The KTB apatite fission-track profiles: building on a firm foundation? Geochimica et Cosmochimica Acta 167, 27-62.

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