Ewch i’r prif gynnwys
Ricardo Ramalho

Dr Ricardo Ramalho

Lecturer in GeoEnvironmental Hazards

Ysgol Gwyddorau'r Ddaear a'r Amgylchedd

Email
RamalhoR@caerdydd.ac.uk
Telephone
+44 29208 75367
Campuses
Y Prif Adeilad, Ystafell 3.15, Plas y Parc, Caerdydd, CF10 3AT
Users
Ar gael fel goruchwyliwr ôl-raddedig

Trosolwyg

I am geologist whose research focuses on the geodynamics and hazards of ocean island volcanoes.

Ocean island volcanoes are some of the most prominent and rapidly-forming structures on Earth, yet their origins are still very enigmatic as they still cannot be explained by conventional plate tectonics. They also feature one of the most dynamic landscapes in our planet, being the source of highly devastating geohazards such as paroxysmal eruptions, giant lateral collapses, and megatsunamis. Research on ocean island volcanoes is thus one of the last frontiers in the comprehension of our Planet’s internal dynamics and is fundamental for countries with sovereignty over volcanic archipelagos, such as the UK.

My central aim is to understand how island volcanoes grow and decay, at different time and spatial scales, and how that evolution reflects the holistic interaction between surface processes and deep earth mechanisms.

My work also focuses on investigating the hazard potential posed by island volcanoes, including on volcanic eruptions (their dynamics, effects and frequency), landslides (trigger mechanisms and effects), tsunamis (generation, propagation and impact), lahars (trigger mechanisms and effects), storms (frequency and impacts), and coastal erosion (as a function of a range of different factors).

My research is therefore very broad, bridging the fields of volcanic geology, plate tectonics & structural geology, geomorphology, stratigraphy, sedimentology, and natural hazards.

My work is very field based (both onshore and offshore), but extends and relies on range of other complementary laboratorial and modelling techniques, making it very interdisciplinary and collaborative in nature.

Keywords:

  • Ocean island volcanoes
  • Geodynamics
  • Hotspots
  • Landscape evolution
  • Landslides
  • Tsunamis
  • Volcanic eruptions

Cyhoeddiad

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2005

Adrannau llyfrau

Cynadleddau

Erthyglau

Llyfrau

Ymchwil

My research focuses on the geodynamics and hazards of ocean island volcanoes. I generally employ an integrative onshore-offshore approach, combining field observations with geochronology and quantitative analyses to unravel the evolution of ocean island volcanoes and their landscapes, at different time and spatial scales. Crucially, my work increasingly focuses on investigating the hazard potential posed by island volcanoes, under a multitude of perspectives. My research activities thus span a variety of topics, chiefly: 

Ocean island evolution, magmatism and volcanic hazard

I am fascinated by how ocean island volcanoes evolve through space and time, as a function of the holistic interaction between internal geodynamics and external factors. I am particularly interested in the evolution of ocean island volcanoes and oceanic hotspots located at stationary or slow-moving plate environments with respect to their melting source (e.g. Cape Verde, Madeira and Canaries), or of those located close to mid-ocean ridges and triple junctions (e.g. Azores).

In these settings my research chiefly focuses on how competing volcanic and intrusive processes govern island growth, how complex uplift/subsidence histories reflect episodic changes in magmatic system behaviour, and how the lack of volcanism does not necessary reflects magmatic quiescence. I am also contributing to research that integrates geological/geodetic/geophysical/remote sensing data to understand active intrusive processes and their surface expression. Additionally, I have been looking at how islands near rifts may be destroyed by tectonic processes.

In terms of volcanic hazard, my research focuses on the use of high-resolution bathymetric surveys in the formulation of solid volcanic hazard assessments on volcanic islands, and on the modulation of volcanic hazard at hydraulically-charged ocean island volcanoes, with links to climate variability.

Hazard potential of volcanogenic tsunamis

Recently, we have shown that a flank collapse at Fogo – one of the most active oceanic volcanoes on Earth – triggered a large tsunami with dire consequences at ~73 ka. This discovery provides another line of evidence that volcanic flank collapses are indeed capable of triggering megatsunamis, addressing a fierce debate over their real hazard potential.

I am currently leading an highly multidisciplinary international research venture to investigate the regional impact of this tsunami, coupled with a detailed investigation of the source, aiming at the incorporation of physical constraints into new, more robust numerical models for the generation, propagation and impact of volcanogenic tsunamis.

Through this research, we hope to answer 3 of the most fundamental questions hampering our scientific understanding of megatsunami hazard: (1) what is the initial magnitude of these waves (in relation to their volume flux)? (2) how fast they dissipate as they propagate into the distance? i.e. are they capable of significant damage across ocean basins? (3) How frequent are these events?

We are also working to establish more solid criteria to identify tsunami deposits on volcanic islands and extract meaningful parameters in event reconstruction.

We are also exploring the hazard potential posed by smaller but much more frequent tsunamis triggered by coastal cliff failures, using an integrative high-resolution onshore/offshore approach coupled with numerical modelling. The idea is to use historical examples to calibrate numerical tools for hazard & risk analysis of this type of events.

We have also recently investigated the tsunami generated by the colossal eruption of Hunga Tonga Hunga Ha'apai in the Pacific Ocean and showed that this was a truly global tsunami generated by a fast-moving atmospheric source in which acoustic-gravity waves radiating from the eruption excited the ocean and transfered energy into it by means of resonance. This air–water-coupled mechanism explains the unusually fast travel times and long duration of the tsunami, as well as its global reach, also leading to higher waves along land masses that rise abruptly from long stretches of deep ocean waters.

Coastal evolution, erosion, shelf sediment dynamics, and island biogeography

My work is incredibly multi-disciplinary and includes contributions to the fields of Earth surface processes, environmental hazards, and in particular coastal science. I am particularly interested on how volcanic island coastlines and shelfs evolve as a function of volcanism, mass wasting, erosion, sedimentation and interaction with biological processes.

We are now working to offer more quantitative insights to the subject, namely through the increased use of a combined onshore/offshore approach, linking fieldwork on land with very high-resolution marine geophysics, and by incorporating the latest advances in geomorphological numerical modelling into our analysis.

I also actively collaborate with biologists and palaeontologists in the study of fossil insular marine biotas and on the influence of island ontogeny and glacio-eustatic oscillations in patterns of marine biogeography. 

Active Research Projects

  • UNTIeD – UNlocking the megaTsunamI Deadlock: using the near-source impacts to constrain tsunami generation by volcanic flank collapses. Funded by FCT Portugal and FEDER (POR Lisboa 2020), €240k (2018–2022). Role: PI.
  • HAZARDOUS - Evaluating HAZARDs related to the formation and development of detrital and lavic “fajãs” in the POrtugUese volcanic archipelagoS. Funded by FCT Portugal, €250k (2021–2024). Role: Co-PI.
  • GEMMA - improving GEodynamic Models in MAcaronesia by reconciling geodetic, geophysical and geological data. Funded by FCT Portugal, €250k (2022–2025). Role: Co-I.
  • Mechanics of dyke intrusion in oblique-slip tectonic settings: Unravelling the causes of the March 2022 rare seismic swarm in São Jorge Island, Azores. NERC Urgency Grant, £100k. Role: Co-PI 

Past Research Projects:

  • MEGAWAVE – Unravelling the hazard potential of tsunamis triggered by volcanic flank collapses. Funded by FCT Portugal, €260k (2016–2021). Role: PI.
  • RV METEOR M155 cruise – The tsunamigenic gravitational flank collapse of Fogo volcano, Cape Verde Islands. Funded by DFG, €169k (2019). Role: Co-PI.
  • SIGHT - SeIsmic and Geochemical constraints on the Madeira HoTspot system. Funded by FCT Portugal, €250k (2018–2022). Role: Co-I.
  • PLATMAR - Development of volcanic island shelves: insights from Sta. Maria Island and implications on hazard assessment, habitat mapping and marine aggregates management. Funded by FCT Portugal, €200k (2016–2020). Role: Co-I & Task Leader.
  • FIRE - Fogo Island volcano: multi disciplinary REsearch on 2014/15 Eruption. Funded by FCT Portugal, €200k (2016–2020). Role: Co-I & Task Leader.
  • Rhodoliths from the Cape Verde Archipelago: insights into climate change and megatsunami sediment dynamics. Funded by DFG, €20k (2018–2021). Role: Co-I.
  • ISLAND FREEBOARD – What can island isostasy tell us about hotspot dynamics. FP7 Marie Curie Fellwoship funded by the ERC, €272k (2013-2016).
  • Investigation of Island Uplift of the Azores Island region. Funded by DFG, €150k (2011–2013). Role: Co-I.

Addysgu

I teach a variety of subjects across geosciences, particularly in themes related to geohazards, geodynamics, geomorphology, volcanism, and field skills.

I currently teach in the following modules:

EA1300 World of Dynamic Environments (Year 1)
EA3306 Advanced Environmental Geology (Year 3)
EAT402 Environmental Hazards in a Changing World (Environmental Hazards MSc)
EAT406 Risk Assessment (Environmental Hazards MSc)
EAT408 Environmental Hazards Case Studies (Environmental Hazards MSc)
EAT401 Individual Dissertation (Environmental Hazards MSc)
EAT409 Remote Sensing of Environmental Hazards (Environmental Hazards MSc)

Bywgraffiad

Academic Positions:

2021: Lecturer, Cardiff University
2016: Senior Research Fellow and Invited Lecturer, Instituto Dom Luiz, University of Lisbon
2013: Marie Curie Independent Outgoing Research Fellow, University of Bristol & Lamont-Doherty Earth Observatory of Columbia University
2011: Postdoctoral Research Assistant, Münster University

Honorary/Adjunct Positions:

Honorary Researcher and Invited Lecturer at Instituto Dom Luiz, University of Lisbon (Portugal).
Adjunct Associate Research Scientist, Lamont-Doherty Earth Observatory of Columbia University (USA).

Education

2010: PhD Earth Sciences, University of Bristol
2004: MSc Dynamic Geology, University of Lisbon
2001: Lic. (Hons) Geology, University of Lisbon

Anrhydeddau a dyfarniadau

  • Springer Thesis Award (2011) - one of a few selected outstanding PhD theses from around the world and across the physical sciences in 2011.
  • Runners-up Best Talk (2007) at the British Geophysical Association Postgraduate Research in Progress Meeting, 2-4 September 2007, Cardiff.

Aelodaethau proffesiynol

  • 2007 – present: Fellow of the Geological Society of London
  • 2008 – present: member of the American Geophysical Union
  • 2011 – present: member of the European Geosciences Union
  • 2012 – present: member of the International Association of Volcanology and Chemistry of Earth's Interior

Meysydd goruchwyliaeth

I am interested in supervising PhD, MSc and MSCi students in the areas of:

  • Geo-environmental hazards
  • Volcanology & volcanic geology
  • Geomorphology of volcanic landscapes
  • Oceanic plate geodynamics & hotspots
  • Coastal evolution of rocky shores
  • Island geological/biological co-evolution
Mae gwyddonwyr yn rhoi esboniad am y tswnami eithriadol a ddigwyddodd yn Tonga

Mae gwyddonwyr yn rhoi esboniad am y tswnami eithriadol a ddigwyddodd yn Tonga

12 June 2022

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