uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Crustal differentiation processes at Krakatau volcano, Indonesia
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
Show others and affiliations
2013 (English)In: Journal of Petrology, ISSN 0022-3530, E-ISSN 1460-2415, Vol. 54, no 1, 149-182 p.Article in journal (Refereed) Published
Abstract [en]

Anak Krakatau is a basaltic andesite cone that has grown following the famous caldera-forming 1883 eruption of Krakatau. It breached sea level in 1927 and since the 1950s has been growing at an average rate of similar to 8 cm a week. We present new major and trace element data combined with whole-rock delta O-18, Sr and Nd isotope data for 1883, 1993 and 2002 Krakatau eruptive products and the surrounding crust. Bombs erupted from Anak Krakatau during 2002 contain frothy metasedimentary and plutonic xenoliths that show variable degrees of thermal metamorphism, plastic deformation and partial melting. Contact-metamorphic minerals such as cordierite and tridymite in metasedimentary xenoliths are consistent with high-temperature metamorphism and incorporation at mid- to upper-crustal depth. Energy-constrained assimilation and fractional crystallization modelling of whole-rock data suggests that the Anak Krakatau magmas have a genetic relationship with the 1883 eruption products. The geochemical impact of crustal contaminants on whole-rock compositions is apparently small, and we conclude that low levels of assimilation of a quartzo-feldspathic sediment are recorded in Anak Krakatau magmas. Plagioclase phenocrysts from the 2002 eruption exhibit disequilibrium textures and complex compositional zoning, however, and are also isotopically variable with a total range in Sr-87/Sr-86 of 0 center dot 7043-0 center dot 7048 as determined by in situ laser ablation inductively coupled plasma mass spectrometry. This suggests that although shallow crustal assimilation appears to have had a limited effect on whole-rock chemistry, a complex late-stage differentiation history is recorded within the magma's cargo of crystals and xenoliths.

Place, publisher, year, edition, pages
2013. Vol. 54, no 1, 149-182 p.
National Category
Earth and Related Environmental Sciences
Research subject
Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics
URN: urn:nbn:se:uu:diva-161215DOI: 10.1093/petrology/egs066ISI: 000312883000006OAI: oai:DiVA.org:uu-161215DiVA: diva2:455280
Available from: 2011-11-09 Created: 2011-11-09 Last updated: 2013-02-04Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Troll, Valentin R.
By organisation
Solid Earth Geology
In the same journal
Journal of Petrology
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 221 hits
ReferencesLink to record
Permanent link

Direct link