The exhumation of the western Greater Caucasus: a thermochronometric study

Stephen Vincent, Andrew Carter, Vladimir Lavrishchev, Samuel Rice, Teimuraz Barabadze, Niels Hovius

Research output: Contribution to journalArticle

Abstract

This study provides 39 new thermochronometric analyses from the western part of the Greater Caucasus, a region in which existing data are extremely limited and of questionable quality. The new results are consistent with field studies that identify Triassic to Middle Jurassic (Cimmerian) and Oligo-Miocene (Alpine) orogenic erosional events. An inverse relationship between the fission track and depositional ages of Oligo-Miocene sedimentary samples also implies some degree of Eocene erosion of the Greater Caucasus and intermediate sediment storage. Cooling ages and field relationships within the core of the range, west of Mt Elbrus, require ~5 km of Permo-Triassic exhumation and restrict the overall amount of Cenozoic exhumation to ~2.5 km. Current exhumation rates are typically low, and do not support a Plio-Pleistocene increase in climate-driven denudation. High (~1 km Ma−1) rates of exhumation are restricted to the southern flank of the range in northwest Georgia. Despite a general lack of significant seismicity within the study region, this exhumation peak is close to the largest instrumentally recorded earthquake in the Caucasus (Ms = 7.0). This may suggest that exhumation is associated with the decoupling of the sedimentary succession from its crystalline basement in the southern part of the range and the inversion of the largely Jurassic fill of the Greater Caucasus basin. Rates of exhumation are compatible with this being driven by active shortening. Further sampling and analysis are required to provide a higher-resolution, low-temperature thermochronology of Alpine exhumation, to isolate the drivers for Palaeogene Dziruli Massif cooling and uplift, and to constrain better the extent of the current, localized phase of rapid exhumation.
Original languageEnglish
Pages (from-to)1-21
Number of pages21
JournalGeological Magazine
Volume148
Issue number1
Early online date5 May 2010
DOIs
Publication statusPublished - 1 Jan 2011
Externally publishedYes

Fingerprint

exhumation
Triassic
Jurassic
Miocene
Cimmerian
cooling
thermochronology
denudation
Paleogene
seismicity
Eocene
fill
uplift
Pleistocene
erosion
earthquake
sampling
climate
basin
sediment

Keywords

  • exhumation
  • uplift
  • fission track
  • Caucasus
  • Dziruli Massif

Cite this

Vincent, S., Carter, A., Lavrishchev, V., Rice, S., Barabadze, T., & Hovius, N. (2011). The exhumation of the western Greater Caucasus: a thermochronometric study. Geological Magazine, 148(1), 1-21. https://doi.org/10.1017/S0016756810000257
Vincent, Stephen ; Carter, Andrew ; Lavrishchev, Vladimir ; Rice, Samuel ; Barabadze, Teimuraz ; Hovius, Niels. / The exhumation of the western Greater Caucasus : a thermochronometric study. In: Geological Magazine. 2011 ; Vol. 148, No. 1. pp. 1-21.
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Vincent, S, Carter, A, Lavrishchev, V, Rice, S, Barabadze, T & Hovius, N 2011, 'The exhumation of the western Greater Caucasus: a thermochronometric study' Geological Magazine, vol. 148, no. 1, pp. 1-21. https://doi.org/10.1017/S0016756810000257

The exhumation of the western Greater Caucasus : a thermochronometric study. / Vincent, Stephen; Carter, Andrew; Lavrishchev, Vladimir; Rice, Samuel; Barabadze, Teimuraz; Hovius, Niels.

In: Geological Magazine, Vol. 148, No. 1, 01.01.2011, p. 1-21.

Research output: Contribution to journalArticle

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Vincent S, Carter A, Lavrishchev V, Rice S, Barabadze T, Hovius N. The exhumation of the western Greater Caucasus: a thermochronometric study. Geological Magazine. 2011 Jan 1;148(1):1-21. https://doi.org/10.1017/S0016756810000257