Volatiles and Large Volcanic Eruptions

Projektin yksityiskohdat

Kuvaus

Flood basalts are the largest manifestations of magmatism and directly related to profound questions about the composition and
dynamics of the mantle, breakup of continents, and climatic history. Their origin and their role in mass extinctions are subjects of
debate because of limited compositional data on the primary flood basalt magmas and their mantle sources. Isotopic and chemical
analyses are used as tracers of terrestrial mantle reservoirs. In the case of flood basalts, utilization of these tools is severely limited by
the complex magmatic differentiation, contamination, and alteration processes that have interfered the compositions of all but few of the
volcanic rocks. Volatile geochemistry (e.g. He isotopes, H2O, S, CO2) of flood basalts is particularly poorly understood due to
outgassing of erupting magmas. The release of volatiles is considered to be the main culprit for mass extinctions, but the environmental
impacts remain poorly quantified due to very limited data on the pre-eruptive volatile characteristics of flood basalts.
We have discovered exceptionally well-preserved picritic flood basalts in the Antarcic and African parts of the Jurassic Karoo magma
province. These picrites are globally rare examples of primitive, nearly undifferentiated and mineralogically pristine flood basalts and
are highly valuable for several reasons:
1-They facilitate chemical and isotopic characterization of two contrasting (Antarctic vs. African) types of primary flood basalt
magmas;
2-Their pristine olivine and Cr-spinel phenocrysts allow application of He and Os isotopic analyses that are crucial for identification of
mantle sources;
3-Their phenocryst-hosted melt inclusions preserve information on the pre-eruptive volatile geochemistry.
Together with our collaborates at the Carnegie Institution for Science and Woods Hole Oceanographic Institution, we will carry out
pioneering measurements of volatile contents (H2O, CO2, S, Cl, F) and He isotopes in the olivine phenocrysts and melt inclusions of
Jurassic picrites. We will also perform high-precision elemental and isotopic (Nd, Sr, Pb, Os) analyses to obtain a comprehensive
geochemical dataset that facilitates characterization of the primary melts and mantle sources of Karoo flood basalts in unprecedented
detail and, ultimately, can help us to clarify the origin of large volcanic eruptions and their environmental influences.
AkronyymiVALVE
TilaKäynnissä
Todellinen alku/loppupvm01/01/201731/12/2020

Rahoitus

  • SUOMEN AKATEMIA: 312 458,00 €

Tutkimustuotos

  • 9 Konferenssiabstrakti
  • 2 Artikkeli

Nd, Sr, Pb, and Os isotopic composition of Luenha picrites suggest a primitive mantle source for the plume component of the Karoo large igneous province

Turunen, S. T., Luttinen, A. V., Heinonen, J. S., Carlson, R. W. & Horan, M. F., tammikuuta 2020, s. 219-220. 2 Sivumäärä.

Tutkimustuotos: KonferenssimateriaalitKonferenssiabstrakti

Open access

Oxygen isotope characteristics of Karoo picrites with a primitive mantle affinity

Iles, K. A., Luttinen, A., Heinonen, J. & Turunen, S., tammikuuta 2020, s. 99-100. 2 Sivumäärä.

Tutkimustuotos: KonferenssimateriaalitKonferenssiabstrakti

Open access

Were Karoo flood basalts derived from a LLSVP-related plume source?

Luttinen, A., Heinonen, J., Turunen, S., Carlson, R. & Horan, M., toukokuuta 2020.

Tutkimustuotos: KonferenssimateriaalitKonferenssiabstrakti

Open access

Lehtileikkeet

Fox News - Verkkouutinen

Sanni Turunen, Arto Luttinen, Jussi Heinonen & Dáud Jamal

04/09/2019

1 kohde/ Medianäkyvyys

Lehdistö/media

Live Science - Verkkouutinen

Sanni Turunen, Arto Luttinen, Jussi Heinonen & Dáud Jamal

03/09/2019

1 kohde/ Medianäkyvyys

Lehdistö/media

Phys.org - Verkkouutinen

Sanni Turunen, Arto Luttinen, Jussi Heinonen & Dáud Jamal

26/08/2019

1 kohde/ Medianäkyvyys

Lehdistö/media