Senckenberg Forschung

Basalt 2013
2 Ascent Zone

a) Tectonic & age control on magmatism
Intra-continental basaltic volcanism commonly forms volcanoes dispersed over large areas and erupted over a long period of
     time, in spite of the fact that the individual volcanoes could be as short lived as a few hours. This type of dispersed intra-
     plate volcanism is often defined as monogenetic volcanism, expressing the short-lived and small-volume eruptions of the
     individual volcanoes that make up the fields. While the eruption duration of each individual volcano in a volcanic field is
     generally short, the life of the entire field can be well over the average lifetime of a composite or stratovolcano, ranging from
     a few thousands to several hundreds of thousands of years. The total magmatic output of an individual volcano of a volcanic
     field is considered to be small and estimated to be several orders of magnitude less than the total magmatic output of a
     composite volcano; however, the total magmatic output of a volcanic field as a whole can be comparable to the average
     magma output rate of a composite volcano of any composition.
     These unique features of intra-continental, dominantly basaltic volcanic fields provide a great opportunity to conduct
     research to understand the internal and external parameters that control how magma reaches the surface from the mantle
     regions, how individual magma batches evolve during ascent, how the structural elements of the lithosphere influence the
     style of volcanism produced by the rising magma and how spatio-temporal variations of the style, volume, chemistry of the
     volcanism could be linked to physico-chemical processes during the ascent of the magma.
     The generally long duration of the activity of a whole volcanic field makes monogenetic volcanism an important parameter to
     consider in sedimentary basin evolution. The accumulated eruptive products and their slowly eroding volcaniclastic material
     could significantly influence the sedimentary history of an evolving basin. The added volcanic material to the basin could help
     to constrain the timing of events by using radiometric dating techniques to solve stratigraphical problems. The eruptive history
     of a basaltic volcanic field, which can span millions of years, could coincide with dramatic climatic and paleoenvironmental 
     changes that can be dated precisely using radiometric dating techniques of preserved volcanic rocks. Therefore, a 
     systematic volcanological and geochronological study of individual volcanoes of a volcanic field can help to draw a detailed
     paleoenvironmental reconstruction, often in combination with paleogeographic reconstructions and erosion rate estimates.
     In this session we would like to invite contributors conducting research on understanding the link between basaltic magma
     ascent and the structural setting of a lithosphere. Presentations targeting key questions that try to explain why and how
     magma forms dispersed ascent zones leading to the formation of volcanic fields are welcomed. We are calling for
     presentations that show the potential link between dispersed volcanism and more central vent-dominated volcanism.
     Research results on the spatio-temporal evolution of small-volume basaltic volcanic fields from the perspective of
     understanding the external versus internal controlling parameters of such variations are encouraged to be submitted to this
     session. New geochronological analytical techniques, case studies, analogue and computer modelling to explain the magma
     ascent from depth to the surface are expected to be presented in this session.

     Karoly Nemeth (Palmerston North/NZ, recent address: Jeddah, Kingdom of Saudi Arabia)
     Zoltan Pecskay (Debrecen/H)

Key Notes  
Zoltan Pecskay
"Age spectra of the Cenozoic volcanic rocks of the Bohemian Massif"