Red X iconGreen tick iconYellow tick icon
Skip to main content Skip to side navigation

Marco BrennaBSc (University of Western Australia), PhD (Massey)

  • Igneous petrology and geochemistry
  • Volcanology
  • Magma ascent dynamics

Office - Geology Gs09
Tel+64 3 479 5634
Email marco.brenna@otago.ac.nz
Google Scholar: Marco Brenna
ORCIDorcid.org/0000-0001-6096-6999

Research Interests

My research spans the interface of magmatic and volcanic processes. I investigate the chemical and petrologic characteristics of igneous rocks to unravel their history. I focus mainly on intraplate alkalic systems such as the Auckland Volcanic Field or the Dunedin Volcano, but have also studied recent eruptions at calc-alkalic arc volcanoes, at Mount Tongariro and Hunga Ha'apai (Tonga). Outlined here are some of my ongoing research projects:

  • Magma generation and ascent dynamics in small-volume intraplate basaltic volcanic systems. My study of the Jeju Island intraplate volcano in South Korea left me with several questions on the mechanisms that allow small-volume and diverse magma batches to erupt in laterally and temporally dispersed volcanic systems. I am currently measuring rates of elemental diffusion in xenocrystic mantle olivines in the Auckland Volcanic Field to estimate rates of magma ascent. The next step will be to model the process of magma accumulation in the mantle and mechanisms triggering ascent.
  • Formation of phonolite-trachyte lineages in intraplate alkalic volcanoes. The Dunedin Volcano (and many others) is composed of lavas ranging in composition from basalt to trachyte and phonolite. Some of these lavas contain mantle peridotite xenoliths, indicative of their fast ascent. Together with colelagues at INGV Rome we are experimentally investigating the conditions that lead to the formation of different magmatic liquid lines of descent.
  • Characterization and eruption dynamics of the 2014-2015 eruption of Hunga Ha'apai (Tonga). I visited and sampled the newly born volcanic cone at Hunga Ha'hapai together with colleagues from the University of Auckland. We collected data ranging from rock samples to characterize the eruption both chemically and physically, underwater bathymetry to reveal features of previous eruption, and drone images of the whole island to generate a 3D model of erosional features.

In addition to these specific projects, I also work on intrusive and extrusive igneous rocks as far afield as Western Australia, Saudi Arabia, Korea and Japan.

A section through a small basaltic volcano at Jeju Island showing the transition from phreatomagmatic-dominated to magmatic-dominated eruption phases.
A section through a small basaltic volcano at Jeju Island showing the transition from phreatomagmatic-dominated to magmatic-dominated eruption phases.

Precipitous basalt and trachyte cliffs at Ulleung Island.
Precipitous basalt and trachyte cliffs at Ulleung Island.

Inspecting the volcanic deposits from the 2009 and 2015 eruptions at Hunga Ha'apai, Tonga.
Inspecting the volcanic deposits from the 2009 and 2015 eruptions at Hunga Ha'apai, Tonga.

Peeking into the crater of the 2012 Te Maari eruption at Mount Tongariro
Peeking into the crater of the 2012 Te Maari eruption at Mount Tongariro

Teaching

View available student research opportunities

Publications

Liu, D., Xu, C., Brenna, M., Liu, X., Li, Q., & Wei, C. (2025). Paleoproterozoic deep carbon cycle recorded in carbonatites. Precambrian Research, 417, 107669. doi: 10.1016/j.precamres.2024.107669 Journal - Research Article

Corella Santa Cruz, C. R., Straub, S. M., Zellmer, G. F., Stirling, C. H., Reid, M. R., Barr, D., Martin, C. E., Brenna, M., & Nemeth, K. (2025). Geochemical and isotopic characterisation of trench sediment at the Hikurangi Margin from IODP sites U1518 and U1520. New Zealand Journal of Geology & Geophysics, 68(1), 120-134. doi: 10.1080/00288306.2023.2280031 Journal - Research Article

Wilson, L. J. E., Giacalone, E., Scott, J. M., Brenna, M., White, J. D. L., le Roux, P. J., … Palmer, M. C., Read, S. E., Reid, M. R., & Stirling, C. H. (2025). Contemporaneous alkaline and subalkaline intraplate magmatism in the Dunedin Volcanic Group, NZ, caused by mantle heterogeneity. New Zealand Journal of Geology & Geophysics, 68(1), 95-119. doi: 10.1080/00288306.2023.2277443 Journal - Research Article

Stenning, A., White, J., & Brenna, M. (2024). A series of magma recharge and mixing events at Mt Charles, Otago Peninsula: Reconstructing the Dunedin volcano. In F. Nelson, H. Jack & S. Chanony (Eds.), Geoscience Society of New Zealand Miscellaneous Publication: Mountains to Sea. 167A, (pp. 233). Wellington, New Zealand: Geoscience Society of New Zealand. [Abstract] Conference Contribution - Published proceedings: Abstract

Stenning, A., Palin, M., White, J., & Brenna, M. (2024). Hot and cold storage within a long-lived crystal mush beneath the Dunedin volcano. In F. Nelson, H. Jack & S. Chanony (Eds.), Geoscience Society of New Zealand Miscellaneous Publication: Mountains to Sea. 167A, (pp. 232). Wellington, New Zealand: Geoscience Society of New Zealand. [Abstract] Conference Contribution - Published proceedings: Abstract

Back to top