Late Cretaceous-Cenozoic Exhumation of the Western Brooks Range, Alaska, Revealed From Apatite and Zircon Fission Track Data

The San Juan Islands of Washington State form a geologically complex province located between the north Cascades, Vancouver Island, and the Olympic Peninsula. We have obtained 53 fission-track dates from the San Juan Islands province that help constrain its late Paleozoic to early Cenozoic tectonic and sedimentary history and its relationship to neighboring geologic terranes. The San Juan Islands can be divided into two main blocks separated by the Haro fault. South of the Haro fault, complexly deformed, metamorphosed, and probably exotic early Paleozoic to early Late Cretaceous rocks form four imbricate thrust plates separated by south- and east-dipping late Early to Late Cretaceous thrust faults. Reset zircon fission-track dates indicate that thrusting may have produced an upside-down geothermal gradient in the uppermost plate, the Decatur terrane. If present, this gradient was probably produced by conductive or frictional heating associated with a now-eroded overlying thrust fault and hot thrust plate. Cretaceous thrusting in the southern San Juan Islands was accompanied by uplift and resetting of apatite fission-track dates. In contrast to correlative rocks of the southern San Juan Islands, Upper Triassic to Lower Cretaceous rocks in and north of the Haro fault zone are essentially unmetamorphosed and only broadly folded. Apatite dates from the Upper Triassic Haro Formation and the Upper Jurassic and Lower Cretaceous Spieden Group indicate they did not participate in Late Cretaceous uplift of the southern San Juan Islands. Together with their basement (the Wrangellia terrane?), these rocks probably acted as a backstop to thrusting. The synorogenic Late Cretaceous Nanaimo basin formed north of the Haro fault in front of the advancing San Juan Islands thrust system. The age of Nanaimo deposition matches uplift (apatite) dates in the southern San Juan Islands, and detrital zircons from the Nanaimo Group yield dates consistent with southern San Juan Islands sources. Burial led to resetting of apatite dates in what is probably the deeper part of the Nanaimo basin.

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Multiple episodes of Cenozoic denudation in the northeastern Brooks Range: fission-track data from the Okpilak batholith, Alaska

Canadian Journal of Earth Sciences ◽

10.1139/e95-092 ◽

1995 ◽

Vol 32 (8) ◽

pp. 1106-1118 ◽

Cited By ~ 13

Author(s):

Paul B. O'sullivan ◽

Catherine L. Hanks ◽

Wesley K. Wallace ◽

Paul F. Green

Keyword(s):

Fission Track ◽

Middle Eocene ◽

Sedimentary Rocks ◽

Late Oligocene ◽

Brooks Range ◽

Rapid Cooling ◽

Zircon Fission Track ◽

Fault Bend ◽

Thrust Sheets ◽

Uplift And Erosion

The northeastern Brooks Range of Alaska is a complex Mesozoic to Cenozoic northward-verging fold and thrust belt. In response to regional compression, shortening in the upper crust has occurred through the duplexing of thrust sheets and formation of associated fault-bend folds. Apatite and zircon fission-track data from the Okpilak batholith and adjacent sedimentary rocks exposed within the northeastern Brooks Range provide new constraints on the timing, magnitude, and rate of cooling of these thrust sheets as they were rapidly denuded in response to uplift during Cenozoic time. Fission-track results indicate that a previously recognized episode of Paleocene cooling was followed by at least two younger episodes of rapid cooling during Middle Eocene and Late Oligocene time. The two younger episodes of rapid cooling are interpreted to reflect denudation in response to uplift resulting from Cenozoic thrusting and related folding. As a result of structural thickening, up to 8 km of material was eroded from the top of the batholith between ~41–45 Ma (Middle Eocene). Renewed shortening and emplacement of an underlying thrust sheet at ~25 Ma (Late Oligocene) resulted in at least 2 km of uplift and erosion of sedimentary rocks immediately north of the batholith. These results suggest that, even though Paleocene uplift and erosion may have occurred across the northeastern Brooks Range, the major episode of thrust faulting, responsible for structural emplacement of the batholith into its present position and kilometre-scale denudation, most likely occurred during Middle Eocene time.

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The Tectonic and Uplift History of the Kuruketage Area in the North-East Edge of the Tarim Basin, China: Constraints from Detrital Zircon and Apatite Fission Track Data

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.330.1067 ◽

2013 ◽

Vol 330 ◽

pp. 1067-1070

Author(s):

Hui Xiao ◽

Wei Han ◽

Feng Guo

Keyword(s):

Late Cretaceous ◽

Tarim Basin ◽

Fission Track ◽

Vitrinite Reflectance ◽

Early Paleozoic ◽

Apatite Fission Track ◽

North East ◽

Zircon Fission Track ◽

History Of ◽

Uplift History

This study uses the application of zircon fission track (ZFT) and apatite fission track (AFT) thermochronometry technique to investigate the tectonic and uplift history of the Kuruketage area, north-east edge of the Tarim Basin. Based on measured ZFT, AFT and equivalent vitrinite reflectance measurements of samples in sedimentary rocks in Kuruketage area, the temperature time evolution history from early Paleozoic strata was modeled. The results show that the youngest peaks of ZFT at 371-392Ma and 328 - 305.7Ma record Hercynian tectonic and uplift event; the AFT peaks at 134.5 - 164Ma, 73 - 100Ma and 35.4Ma mainly represent the Late-Cretaceous tectonic and uplift event in Kuruketage area. The AFT thermal modeling results from the early Paleozoic strata indicate that the maximum paleo-temperature (at 140 215°C) experienced in late Silurian to early Devonian, and the strata temperature decreased to about 120°C before the Late-Cretaceous.

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Fission-track analysis unravels the denudation history of the Bonar Range in the footwall of the Alpine Fault, South Island, New Zealand

Geological Magazine ◽

10.1017/s0016756810000208 ◽

2010 ◽

Vol 147 (6) ◽

pp. 801-813 ◽

Cited By ~ 13

Author(s):

UWE RING ◽

MATTHIAS BERNET

Keyword(s):

New Zealand ◽

Late Cretaceous ◽

Fission Track ◽

Southern Alps ◽

Exhumation Rate ◽

Alpine Fault ◽

Zircon Fission Track ◽

Fission Track Thermochronology ◽

Late Tertiary ◽

History Of

AbstractWe apply fission-track thermochronology to shed new light on the tectonic history of Zealandia during Late Cretaceous continental extension and the onset of Late Tertiary mountain building in the Southern Alps of New Zealand. The Southern Alps are one of the fastest erosionally exhuming mountain belts on Earth. Exhumation of the Bonar Range in Westland just to the northwest of the Alpine Fault is orders of magnitude slower. We report apatite and zircon fission-track ages from samples that were collected along an ENE–WSW profile across the central Bonar Range, parallel to the tectonic transport direction of a prominent ductile fabric in the basement gneiss. Zircon fission-track (ZFT) ages show a large spread from 121.9 ± 12.1 Ma to 74.9 ± 7.2 Ma (1σ errors). The youngest ZFT ages of 78 to 75 Ma occur at low elevations on either side of the Bonar Range and become older towards the top of the range, thereby showing a symmetric pattern parallel to the ENE-trending profile across the range. Age–elevation relationships suggest an exhumation rate of 50–100 m Ma−1. We relate the ZFT ages to slow erosion of a tectonically inactive spot in the Late Cretaceous magmatic arc of Zealandia. Therefore, the first main significance of the paper is that it demonstrates that not all of 110–90 Ma Zealandia was necessarily participating in extreme core complex-related extension but that there were enclaves of lithosphere that underwent slow erosion. The apatite fission-track (AFT) ages range from 11.1 ± 1.9 Ma to 5.3 ± 1.0 Ma and age–elevation relationships suggest an exhumation rate of c. 200 m Ma−1. We relate the AFT ages to the inception of transpressive motion across the Alpine Fault and modest exhumation in its footwall in Late Miocene times. If so, the second significant point of this paper is that transpressive motion across the Alpine Fault was already under way by c. 11 Ma.

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Thermal history of the Maramureş area (Northern Romania) constrained by zircon fission track analysis: Cretaceous metamorphism and Late Cretaceous to Paleocene exhumation

Geologica Carpathica ◽

10.2478/geoca-2013-0026 ◽

2013 ◽

Vol 64 (5) ◽

pp. 383-398 ◽

Cited By ~ 7

Author(s):

Heike R. Gröger ◽

Matthias Tischler ◽

Bernhard Fügenschuh ◽

Stefan M. Schmid

Keyword(s):

Late Cretaceous ◽

Thermal History ◽

Fission Track ◽

Structural Evolution ◽

Published Data ◽

Metamorphic Overprint ◽

Sedimentary Evolution ◽

Zircon Fission Track ◽

Eastern Carpathians ◽

History Of

Abstract This study presents zircon fission track data from the Bucovinian nappe stack (northern part of the Inner Eastern Carpathians, Rodna Mountains) and a neighbouring part of the Biharia nappe system (Preluca massif) in order to unravel the thermal history of the area and its structural evolution by integrating the fission track data with published data on the tectonic and sedimentary evolution of the area. The increase of metamorphic temperatures towards the SW detected by the zircon fission track data suggests SW-wards increasing tectonic overburden (up to at least 15 km) and hence top NE thrusting. Sub-greenschist facies conditions during the Alpine metamorphic overprint only caused partial annealing of fission tracks in zircon in the external main chain of the Central Eastern Carpathians. Full annealing of zircon points to at least 300 °C in the more internal elements (Rodna Mountains and Preluca massif). The zircon fission track central and single grain ages largely reflect Late Cretaceous cooling and exhumation. A combination of fission track data and stratigraphic constraints points to predominantly tectonic differential exhumation by some 7-11 km, connected to massive Late Cretaceous extension not yet detected in the area. Later events such as the latest Cretaceous (“Laramian”) juxtaposition of the nappe pile with the internal Moldavides, causing exhumation by erosion, re-burial by sedimentation and tectonic loading during the Cenozoic had no impact on the zircon fission track data; unfortunately it prevented a study of the low temperature part of the Late Cretaceous exhumation history.

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Thermal history of the Maramureş area (Northern Romania) constrained by zircon fission track analysis: Cretaceous metamorphism and Late Cretaceous to Paleocene exhumation

Geologica Carpathica ◽

10.2478/geoca-2013-00026 ◽

2013 ◽

Vol 0 (0) ◽

Author(s):

Heike R. Gröger ◽

Matthias Tischler ◽

Bernhard Fügenschuh ◽

M. Schmid

Keyword(s):

Late Cretaceous ◽

Thermal History ◽

Fission Track ◽

Fission Track Analysis ◽

Zircon Fission Track ◽

History Of ◽

Track Analysis

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Fast extension but little exhumation: the Vari detachment in the Cyclades, Greece

Geological Magazine ◽

10.1017/s0016756803007799 ◽

2003 ◽

Vol 140 (3) ◽

pp. 245-252 ◽

Cited By ~ 54

Author(s):

UWE RING ◽

STUART N. THOMSON ◽

MICHAEL BRÖCKER

Keyword(s):

Late Cretaceous ◽

Fission Track ◽

Regional Scale ◽

Slip Rate ◽

Aegean Sea ◽

Apatite Fission Track ◽

Rapid Cooling ◽

Magmatic Arc ◽

Zircon Fission Track

Markedly different cooling histories for the hanging- and footwall of the Vari detachment on Syros and Tinos islands, Greece, are revealed by zircon and apatite fission-track data. The Vari/Akrotiri unit in the hangingwall cooled slowly at rates of 5–15 °C Myr−1 since Late Cretaceous times. Samples from the Cycladic blueschist unit in the footwall of the detachment on Tinos Island have a mean zircon fission-track age of 10.0±1.0 Ma, which together with a published mean apatite fission-track age of 9.4±0.5 Ma indicates rapid cooling at rates of at least ∼60 °C Myr−1. We derive a minimum slip rate of ∼6.5 km Myr−1 and a displacement of <∼20 km and propose that the development of the detachment in the thermally softened magmatic arc aided fast displacement. Intra-arc extension accomplished the final ∼6–9 km of exhumation of the Cycladic blueschists from ∼60 km depth. The fast-slipping intra-arc detachments did not cause much exhumation, but were important for regional-scale extension and the formation of the Aegean Sea.

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Late Cretaceous–Cenozoic thermochronology in the southern Songliao Basin, NE China: New insights from apatite and zircon fission track analysis

Journal of Asian Earth Sciences ◽

10.1016/j.jseaes.2018.04.015 ◽

2018 ◽

Vol 160 ◽

pp. 95-106 ◽

Cited By ~ 13

Author(s):

Yinhang Cheng ◽

Shaoyi Wang ◽

Ying Li ◽

Cong Ao ◽

Yanfeng Li ◽

...

Keyword(s):

Late Cretaceous ◽

Fission Track ◽

Songliao Basin ◽

Ne China ◽

Fission Track Analysis ◽

Zircon Fission Track ◽

Track Analysis

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Burial and Exhumation History of the Lujing Uranium Ore Field, Zhuguangshan Complex, South China: Evidence from Low-Temperature Thermochronology

Minerals ◽

10.3390/min11020116 ◽

2021 ◽

Vol 11 (2) ◽

pp. 116

Author(s):

Yue Sun ◽

Barry P. Kohn ◽

Samuel C. Boone ◽

Dongsheng Wang ◽

Kaixing Wang

Keyword(s):

Early Cretaceous ◽

Late Cretaceous ◽

South China ◽

Thermal History ◽

Fission Track ◽

Thermal Evolution ◽

Negative Relationship ◽

The Tibetan Plateau ◽

Uranium Ore ◽

Production Area

The Zhuguangshan complex hosts the main uranium production area in South China. We report (U-Th)/He and fission track thermochronological data from Triassic–Jurassic mineralized and non-mineralized granites and overlying Cambrian and Cretaceous sandstone units from the Lujing uranium ore field (LUOF) to constrain the upper crustal tectono-thermal evolution of the central Zhuguangshan complex. Two Cambrian sandstones yield reproducible zircon (U-Th)/He (ZHe) ages of 133–106 Ma and low effective uranium (eU) content (270–776 ppm). One Upper Cretaceous sandstone and seven Mesozoic granites are characterized by significant variability in ZHe ages (154–83 Ma and 167–36 Ma, respectively), which show a negative relationship with eU content (244–1098 ppm and 402–4615 ppm), suggesting that the observed age dispersion can be attributed to the effect of radiation damage accumulation on 4He diffusion. Correspondence between ZHe ages from sandstones and granites indicates that surrounding sedimentary rocks and igneous intrusions supplied sediment to the Cretaceous–Paleogene Fengzhou Basin lying adjacent to the LUOF. The concordance of apatite fission track (AFT) central ages (61–54 Ma) and unimodal distributions of confined track lengths of five samples from different rock units suggest that both sandstone and granite samples experienced a similar cooling history throughout the entire apatite partial annealing zone (~110–60 °C). Apatite (U-Th-Sm)/He (AHe) ages from six non-mineralized samples range from 67 to 19 Ma, with no apparent correlation to eU content (2–78 ppm). Thermal history modeling of data suggests that the LUOF experienced relatively rapid Early Cretaceous cooling. In most samples, this was followed by the latest Early Cretaceous–Late Cretaceous reheating and subsequent latest Late Cretaceous–Recent cooling to surface temperatures. This history is considered as a response to the transmission of far-field stresses, involving alternating periods of regional compression and extension, related to paleo-Pacific plate subduction and subsequent rollback followed by Late Paleogene–Recent India–Asia collision and associated uplift and eastward extrusion of the Tibetan Plateau. Thermal history models are consistent with the Fengzhou Basin having been significantly more extensive in the Late Cretaceous–Early Paleogene, covering much of the LUOF. Uranium ore bodies which may have formed prior to the Late Cretaceous may have been eroded by as much as ~1.2 to 4.8 km during the latest Late Cretaceous–Recent denudation.

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Downstream Changes of Alpine Zircon Fission-Track Ages in the Rhone and Rhine Rivers

Journal of Sedimentary Research ◽

10.1306/041003740082 ◽

2004 ◽

Vol 74 (1) ◽

pp. 82-94 ◽

Cited By ~ 36

Author(s):

M. Bernet ◽

M. T. Brandon ◽

J. I. Garver ◽

B. Molitor

Keyword(s):

Fission Track ◽

Zircon Fission Track ◽

Fission Track Ages

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