Abstract
To determine the mechanisms responsible for mountain belt growth, it is important to accurately establish the timing of surface uplift. Here we exploit the altitude control on the production rate of in situ cosmogenic nuclides to test the hypothesis that the Andes was uplifted in the late Miocene. High concentrations of in situ cosmogenic 3He (3Hecos) have previously been measured in alluvial boulders on the western flank of the Central Andes, northern Chile (Evenstar et al. 2009). These are consistent with deposition soon after formation of the surface (13–14 Ma). We have modeled the accumulation of cosmogenic 3He in several different surface uplift scenarios and compared them to the measured concentrations. The measured 3Hecos concentrations are too high to be produced by late Miocene uplift and imply that the western flank of the Andean Cordillera attained a substantial part of its current elevation prior to 14 Myr ago.
| Original language | English |
|---|---|
| Pages (from-to) | 8448-8455 |
| Number of pages | 8 |
| Journal | Geophysical Research Letters |
| Volume | 42 |
| Issue number | 20 |
| Early online date | 12 Oct 2015 |
| DOIs | |
| Publication status | Published - 28 Oct 2015 |
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Keywords
- Andean uplift
- Chile
- cosmogenic Isotopes
- Longitudinal Valley
- paleoelevation
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)
- Geophysics
Cite this
Slow Cenozoic uplift of the western Andean Cordillera indicated by cosmogenic 3He in alluvial boulders from the Pacific Planation Surface. / Evenstar, Laura A.; Stuart, Finlay M.; Hartley, Adrian J.; Tattitch, Brain.
In: Geophysical Research Letters, Vol. 42, No. 20, 28.10.2015, p. 8448-8455.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Slow Cenozoic uplift of the western Andean Cordillera indicated by cosmogenic 3He in alluvial boulders from the Pacific Planation Surface
AU - Evenstar, Laura A.
AU - Stuart, Finlay M.
AU - Hartley, Adrian J.
AU - Tattitch, Brain
N1 - This material is based upon work supported by NERC grant (NER/S/A/2003/11945) and BHP Billiton. Data used in this study are provided from Evenstar et al. [2009] and from modelling detailed in the supporting information. We are grateful to Philip G. Roxby, Steve Sparks and Shasta Marrero for their help with preparation of the manuscript.
PY - 2015/10/28
Y1 - 2015/10/28
N2 - To determine the mechanisms responsible for mountain belt growth, it is important to accurately establish the timing of surface uplift. Here we exploit the altitude control on the production rate of in situ cosmogenic nuclides to test the hypothesis that the Andes was uplifted in the late Miocene. High concentrations of in situ cosmogenic 3He (3Hecos) have previously been measured in alluvial boulders on the western flank of the Central Andes, northern Chile (Evenstar et al. 2009). These are consistent with deposition soon after formation of the surface (13–14 Ma). We have modeled the accumulation of cosmogenic 3He in several different surface uplift scenarios and compared them to the measured concentrations. The measured 3Hecos concentrations are too high to be produced by late Miocene uplift and imply that the western flank of the Andean Cordillera attained a substantial part of its current elevation prior to 14 Myr ago.
AB - To determine the mechanisms responsible for mountain belt growth, it is important to accurately establish the timing of surface uplift. Here we exploit the altitude control on the production rate of in situ cosmogenic nuclides to test the hypothesis that the Andes was uplifted in the late Miocene. High concentrations of in situ cosmogenic 3He (3Hecos) have previously been measured in alluvial boulders on the western flank of the Central Andes, northern Chile (Evenstar et al. 2009). These are consistent with deposition soon after formation of the surface (13–14 Ma). We have modeled the accumulation of cosmogenic 3He in several different surface uplift scenarios and compared them to the measured concentrations. The measured 3Hecos concentrations are too high to be produced by late Miocene uplift and imply that the western flank of the Andean Cordillera attained a substantial part of its current elevation prior to 14 Myr ago.
KW - Andean uplift
KW - Chile
KW - cosmogenic Isotopes
KW - Longitudinal Valley
KW - paleoelevation
UR - http://www.scopus.com/inward/record.url?scp=84946594091&partnerID=8YFLogxK
U2 - 10.1002/2015GL065959
DO - 10.1002/2015GL065959
M3 - Article
VL - 42
SP - 8448
EP - 8455
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 20
ER -