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Other research product . 2019

Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard)

Hindshaw, Ruth S.; Tosca, Nicholas J.; Piotrowski, Alexander M.; Tipper, Edward T.;
Open Access
English
Published: 10 Jan 2019
Abstract
The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circum-Arctic source regions are poorly characterised in terms of their Sr and Nd isotopic compositions. In this study we present Sr and Nd isotope data from the Paleogene Central Basin sediments of Svalbard, including the first published data of stream suspended sediments from Svalbard. The stream suspended sediments exhibit considerable isotopic variation (εNd = −20.6 to −13.4; 87Sr ∕ 86Sr = 0.73421 to 0.74704) which can be related to the depositional history of the sedimentary formations from which they are derived. In combination with analysis of the clay mineralogy of catchment rocks and sediments, we suggest that the Central Basin sedimentary rocks were derived from two sources. One source is Proterozoic sediments derived from Greenlandic basement rocks which are rich in illite and have high 87Sr ∕ 86Sr and low εNd values. The second source is Carboniferous to Jurassic sediments derived from Siberian basalts which are rich in smectite and have low 87Sr ∕ 86Sr and high εNd values. Due to a change in depositional conditions throughout the Paleogene (from deep sea to continental) the relative proportions of these two sources vary in the Central Basin formations. The modern stream suspended sediment isotopic composition is then controlled by modern processes, in particular glaciation, which determines the present-day exposure of the formations and therefore the relative contribution of each formation to the stream suspended sediment load. This study demonstrates that the Nd isotopic composition of stream suspended sediments exhibits seasonal variation, which likely mirrors longer-term hydrological changes, with implications for source provenance studies based on fixed end-members through time.
110 references, page 1 of 11

Arndt, N. T. and Goldstein, S. L.: Use and abuse of crust-formation ages, Geology, 15, 893-895, 1987.

Aubert, D., Stille, P., and Probst, A.: REE fractionation during granite weathering and removal by waters and suspended loads: Sr and Nd isotopic evidence, Geochim. Cosmochim. Ac., 65, 387- 406, 2001. [OpenAIRE]

Awwiller, D. N.: Geochronology and mass transfer in Gulf Coast mudrocks (south-central Texas, U.S.A.): Rb-Sr, Sm-Nd and REE systematics, Chem. Geol., 116, 61-84, 1994.

Awwiller, D. N. and Mack, L. E.: Diagenetic modification of Sm-Nd model ages in Tertiary sandstones and shales, Texas Gulf Coast, Geology, 19, 311-314, 1991.

Babechuk, M. G., Widdowson, M., Murphy, M., and Kamber, B. S.: A combined Y/Ho, high field strength element (HFSE) and Nd isotope perspective on basalt weathering, Deccan Traps, India, Chem. Geol., 369, 25-41, 2015.

Bayon, G., Toucanne, S., Skonieczny, C., André, L., Bermell, S., Cheron, S., Dennielou, B., Etoubleau, J., Freslon, N., Gauchery, T., Germain, Y., Jorry, S. J., Ménot, G., Monin, L., Ponzevera, E., Rouget, M.-L., Tachikawa, K., and Barrat, J. A.: Rare earth elements and neodymium isotopes in world river sediments revisited, Geochim. Cosmochim. Ac., 170, 17-38, https://doi.org/10.1016/j.gca.2015.08.001, 2015. [OpenAIRE]

Bernstein, S., Kelemen, P. B., Tegner, C., Kurz, M. D., Blusztajn, J., and Brooks, C. K.: Post-breakup basaltic magmatism along the East Greenland Tertiary rifted margin, Earth Planet. Sc. Lett., 160, 845-862, 1998.

Bock, B., McLennan, S. M., and Hanson, G. N.: Rare earth element redistribution and its effects on the neodymium isotope system in the Austin Glen Member of the Normanskill Formation, New York, USA, Geochim. Cosmochim. Ac., 58, 5245-5253, 1994.

Bue, E. P. and Andresen, A.: Constraining depositional models in the Barents Sea region using detrital zircon U-Pb data from Mesozoic sediments in Svalbard, in: Sediment provenance studies in hydrocarbon exploration and production, edited by: Scott, R. A., Smyth, H. R., Morton, A. C., and Richardson, N., no. 386 in Special Publications, Geological Society, Bath, UK, 261-279, 2014.

Bullen, T., White, A., Blum, A., Harden, J., and Schulz, M.: Chemical weathering of a soil chronosequence on granitoid alluvium: II. Mineralogic and isotopic constraints on the behavior of strontium, Geochim. Cosmochim. Ac., 61, 291-306, 1997.

Funded by
SNSF| Weathering processes in an Arctic shale catchment
Project
  • Funder: Swiss National Science Foundation (SNSF)
  • Project Code: PBEZP2_137335
  • Funding stream: Careers;Fellowships | Fellowships for prospective researchers
,
SNSF| Edition der Briefe von Leonhard Ragaz. 3. Band (1933-1945)
Project
  • Funder: Swiss National Science Foundation (SNSF)
  • Project Code: 1000-001865
  • Funding stream: Projects | Project funding ; Project funding | Project funding (Div. I-III)
,
EC| LITING
Project
LITING
Lithium isotopes as a tracer for changes in interglacial-glacial weathering processes
  • Funder: European Commission (EC)
  • Project Code: 331501
  • Funding stream: FP7 | SP3 | PEOPLE
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