Fluid inclusions occur in natural crystals and can be simply considered as sealed microscopic (usually < 50 mm in length) vacuum flasks that contain a sample of fluid trapped during (or after) formation of the host crystal. Determination of the chemistry of the fluid components trapped in the crystal cavity provides fundamental information which can facilitate the reconstruction of the conditions of mineral growth. This in turn leads to a better understanding of the physical and chemical environment of such economically important geological processes as petroleum and ore deposition. Fluid inclusions provide a record of fluids present during rock evolution, so they can be used to expand the understanding of the petrogenesis of rocks by providing significant information (i.e., temperature, pressure, density and composition) concerning the role of fluid that formed or traversed the rock.

The GeoFluids Research Group has a track record in the study of fluid inclusions from a worldwide range of geological settings including the onshore and offshore Irish Massif (Irish granites, Irish vein mineral deposits, Porcupine, Rockall, Celtic Sea and Fastnet Basins), US (Herkimer diamonds, New York, Sierra Nevada Granites), Canada (Newfoundland Basin, Houghton Meteorite Impact Crater, Devon Island), South America (Brazilian Carbonatites; Petroleum Charge Studies of the Llanos Field Colombia) and offshore Scotland (Clair Field). These projects have exposed the Group to a wide range of fluid inclusion compositions including aqueous, carbonic and hydrocarbon (methane to bitumens) bearing fluid inclusions. Furthermore, the Group has interacted through these projects with other Irish (e.g. UCD, TCD, GSI) and international research institutes (e.g. CREGU France, U. Aberdeen, U. Kingston, Inst. Geol. Nuclear Sc., New Zealand).

The Geofluids Laboratory regularly receives research contracts from the oil exploration and production sector, from around the world, to carry out oil charge studies on well cuttings and core samples. 



Clockwise starting from top left:

  1. Trails and clusters of aqueous rich fluid inclusions in quartz from Oughterard granite, Ireland.
  2. Photomicrograph of isolated hydrocarbon Fls characterized by dark coloured liquid phase and blue fluorescence under UV light.
  3. A linear arrangement of small size two-phase aqueous-rich fluid inclusions and a larger and more isolated multiphase fluid inclusion hosted within nepheline, in tinguaite from Pocos de Caldas, Brazil.
  4. Three-phase solid-rich aqueous-carbonic inclusions occurring in an emerald crystal sampled from the Piteiras Mine, Itabira, Minas Gerais State, Brazil.



geology, mineralogy, gemmology, petroleum studies


Group Members

Prof. Martin Feely (Director), Dr. Alessandra Costanzo (Lab Manager) 

Geofluids Research Laboratory (Equipment list)


Linkam THMSG600 at the GeoFluids Research Lab, NUIG.

  1. Microthermometric stage number 1: Linkam THMS 600 heating-freezing stage mounted on a Nikon Labophot transmission light microscope (x10 to x100 special lenses) and fitted with a digital camera feeding to Lucia Archive Imaging Software on dedicated computer.
  2. Microthermometric stage number 2: Linkam THMS 600 heating-freezing stage being used for Fluorescence Lifetime experiments.
  3. Microthermometric stage number 3: Linkam THMSG 600 heating-freezing stage mounted on an Olympus transmitted light microscope (x10 to x100 special lenses) with digital camera feeding to a dedicated computer loaded with the Linksys 32DV imaging and heating control software.
  4. UV-Fluorescence Microscope (Nikon Eclipse E200 Pol) with Y-FL Epi-Fluorescence attachment and digital camera linked to dedicated PC for image capture and analyses.
  5. Nikon Labophot (1) with Nikon conventional camera attachment.
  6. Horiba LabRam II Laser Raman spectrometer. The instrument is equipped with a 600 diffraction grating, a confocal and optical filter system, a Peltier-cooled CCD detector, and is coupled to an Olympus BX51 microscope 

Rock thin sections and doubly polished fluid inclusion wafers are prepared on campus in Earth and Ocean Sciences’ rock cutting and sectioning facility. 

Other campus facilities

Fluorescence Lifetime Imaging Microscope (used for analysis of single hydrocarbon bearing fluid inclusions) in collaboration with Dr Alan Ryder, Chemistry, NUIG.

Structured Light Illumination Microscope (used for 3D imaging of hydrocarbon bearing fluid inclusions) in collaboration with Prof. Dockery, Anatomy, NUIG.