Dr Janaina Avila

Honorary Lecturer

Dr Ávila has a PhD in Earth Sciences (2011) from the Australian National University (ANU). She held postdoctoral appointments at the University of São Paulo from 2011 to 2013 and ANU from 2013 to 2014. Between 2013 and 2014, Dr Ávila was a Postdoctoral Fellow under a Research in Business grant from the Australia Department of Innovation. During that period, she worked in partnership with the RSES SHRIMP team and the Australian Scientific Instruments (ASI) scientists in a range of subjects related to improvements in performance of measurements of stable isotopes in the SHRIMP instruments (SHRIMP-II and SHRIMP-SI). As a Postdoctoral Fellow (from March 2013 to May 2014) and as a Research Fellow (from June 2014 to February 2021) at RSES, Dr Ávila provided strategic advice and support to a wide range of multidisciplinary research projects, from application of stable isotopes to constrain atmospheric conditions in the Archean, fluid migration in petroleum systems, models for subduction zones, continental weathering, and more recently in the field of archaeological sciences. She is a multidisciplinary researcher with high-level technical knowledge and experience in the acquisition and interpretation of in situ measurements of stable isotopes (C, N, O, S, OH) in glass and minerals from biogenic and geologic environments. 

Dr Ávila research interest centres around the application of ion microprobes to the understanding of the isotopic nature of terrestrial and extraterrestrial materials at the microscale. In particular, she is interested in new analytical developments and applications that extend the use of in situ isotopic measurements in earth and planetary sciences. Current areas of interest include: (1) environmental and biological evolutions on early Earth, and their influences on the chemical evolution of the atmosphere and oceans, (2) factors influencing isotopic fractionation (mass-dependent and mass-independent fractionation) associated to sulfur and oxygen isotopes in terrestrial and extraterrestrial materials, (3) sulfur and oxygen isotopic signatures of biological processes, and (4) technique development and innovation of in-situ meaurements of stable and radiogenic isotopes using the ion microprobe.


Ph.D. Cosmochemistry/Planetary Science, 2011, ANU
M.Sc. Earth Sciences, 2005, UFRGS
B.Sc. Geology, 2003. UFRGS

Research interests

  • Development and applications of secondary ion mass spectrometry within earth and planetary sciences
  • Stable isotopes
  • Cosmochemistry and Cosmochronology

Research Highlights

The great oxygenation of the Earth's atmosphere revisited

To understand when, how, and how quickly oxygen has become a component of our atmosphere between about 2.5 and 2.2 billion years ago, an international research team involving RSES-ANU has studied the systematics of the four isotopes of sulfur in more than 700 meters of Australian sedimentary deposits. The results show that the oxygenation of the planet began much earlier than traditionally admitted and that its recording was not synchronous from one continent to another (Australia, South Africa, North America) but spread in time over almost 300 million years. This apparent shift reflects a local effect related to oxidative weathering of older continental surfaces.

In the absence of oxygen in the atmosphere, the UV photolysis of sulfur dioxide (SO2) released by volcanic activity results in the production of sulfur compounds characterized by very specific isotopic fractionations defined as “mass independent” (noted , MIF-S). When dissolved in the ocean, these sulfur compounds transfer this isotopic anomaly to the sedimentary record during their precipitation in the form of pyrite, for example. In the presence of atmospheric oxygen, these particular mass-independent isotopic fractionations disappear. The great oxygenation of the Earth's atmosphere (Great Oxidation Event, GOE) between 2.5 and 2.2 billion years ago (Ga) was defined as the time interval during which a sufficient amount of atmospheric oxygen was present to prevent the production and transfer of these isotopic anomalies into the sedimentary record. The disappearance of these isotopic anomalies in South African sediments over a few meters of sediment thickness, led previous studies to propose that the increase of oxygen in the atmosphere was rapid (less than 10 million years) and globally synchronous at around 2.32 Ga worldwide. However, the presence of large sedimentary gaps in the South African sequences implies that this oxygenation model remains loosely constrained.

“In order to better constrain the mechanisms, magnitude, and duration of the GOE, we conducted a drilling campaign in the Hamersley Basin in Western Australia to study a representative sampling that intersects the period between 2.5 and 2.2 Ga associated with the GOE. Unlike its equivalents in South Africa and North America, the sedimentary sequence studied, the Turee Creek Group, does not show major sedimentary discontinuities,” said Professor Pascal Philippot from University of Montpellier and IPGP, lead investigator of the study.

The analysis of isotopes of sulfur with high stratigraphic resolution shows a relatively homogeneous MIF-S signal of low amplitude (1 ± 0.5 ‰) on all the cores. This signal is punctuated by several sedimentary intervals in which the sulphides do not exhibit MIF-S anomalies. The presence of deposits without MIF-S implies that a significant amount of oxygen were present in the atmosphere as early as 2.45 Ga. The MIF-S signal on the order of 1 ‰ represents the average of the isotopic anomalies measured in the sulphides of the Archean period (4.0 to 2.5 Ga) prior to the GOE. The record of such an anomaly over more than 700 meters of drill cores cannot be explained by atmospheric processes, but it is best attributed to oxidative weathering of older (Archean) continental surfaces and the recycling of a sulphate reservoir of homogeneous isotopic composition of the order of 1‰ in the ocean. “This model allows us to explain that the MIF-S record in sediments of South Africa, North America, and Australia is not synchronous because it depends on local weathering surfaces. These results imply that the current paradigm of defining the GOE at 2.33-2.32 Ga based on the last occurrence of MIF-S in South Africa must be abandoned”, said Professor Pascal Philippot.

RSES-ANU scientists Dr Janaína Ávila and Professor Trevor Ireland, co-authors of the research published in Nature Communications, said the detailed and extensive dataset produced in this study has enable to constraint the timing of the Great Oxidation Event more accurately than previous studies. “Our data indicate that since ca. 2.45 Ga free oxygen was an important component of the Earth’s atmosphere being capable to drive oxidative weathering on land”, said Dr Janaína Ávila.

“Before 2.45Ga, the Earth’s atmosphere and oceans had extremely low levels of oxygen. Several studies indicate that the O2 content of the atmosphere was probably less than 0.001% of the present atmospheric level. During the GOE, the transition from a low oxygen atmosphere to an atmosphere characterized by oxic-suboxic conditions is linked in time with a series of global glacial events. Our data suggest that the rise of atmospheric oxygen occurred around 2.45 Ga or earlier and was not a rapid and synchronous event from one continent to another as previously thought”, said Dr Janaína Ávila.

“Due to recent advances on instrumental capabilities of SHRIMP-SI, an ion microprobe developed by the ANU-Research School of Earth Sciences, we now have the ability to measure with high precision the four isotopes of sulfur in individual domains in single grains. Ion microprobe analysis offers spatial control of measurements that is unmatched by any other technique, allowing isotopic data to be correlated with other geochronological, geochemical, and textural information”, said Dr Janaína Ávila.

Laboratories and organizations involved: Paris Institute of Earth Physics (IPGP / CNRS / Paris Diderot University) and Montpellier Geosciences (Montpellier Geosciences / OREME, University of Montpellier / CNRS / West Indies University), Research School of Earth Sciences (Australian National University, Australia), Ocean Geosciences Laboratory (LGO / IUEM, CNRS / UBO / UBS), John de Laeter Center for Isotope Research (Curtin University, Australia), Biogeosciences (EPHE / University of Bourgogne Franche-Comté / CNRS) and School of Biological, Earth and Environmental Sciences (University of New South Wales, Australia).

Source: Globally asynchronous sulphur isotope signals require re-definition of the Great Oxidation Event. 2018. Philippot, P., Ávila, J., Killingsworth, B., Tessalina, S., Baton, F., Caquineau, T., Muller, E., Pecoits, E., Cartigny, P., Lalonde, S., Ireland, T., Thomazo, C., Van Kranendonk, M.J. and Busigny, V., Nature Communications, DOI: 10.1038/s41467-018-04621-x, 8 juin 2018


Multiple sulfur isotope analysis of sedimentary pyrites with SHRIMP-SI: unravelling complex depositional and post-depositional processes

The sulfur isotopic record of Archean and Paleoproterozoic sedimentary rocks places important constraints on the timing of atmospheric oxygenation. However, many of these ancient rocks have endured several post-depositional processes (e.g., diagenetic, magmatic, hydrothermal, and metamorphic) over geological time so that the original isotopic signature from the early atmosphere and biosphere is now largely overprinted. In situ SHRIMP-SI measurements of multiple sulfur isotopes (32S, 33S, 34S, 36S) in pyrite now allow Δ33S to be determined with internal errors better than 0.05‰ (2SE) and reproducibility about 0.1‰ (2SD). Charge mode measurements [1] of 36S allow Δ36S values to be determined with internal precisions of ± 0.2‰ (2SE) and reproducibility better than 0.25‰ (2SD). This level of precision permits identification, at the micron scale, of preserved isotopic signatures of ancient atmospheric chemical and biological activity, as well as overprinted secondary processes.

[1] Ireland et al (2014) Int. J. of Mass Spect. 359, 26-37.

Measurements of oxygen isotope ratios with the new SHRIMP-SI: high precision analyses of zircon reference materials

The potential for oxygen isotopic analysis of zircon (ZrSiO4) has been recognized for quite some time. Due to its refractory nature and widespread occurrence in many geological environments, zircon d18O values offer unique insights into a wide range of geological processes. The recently commissioned SHRIMP-SI has been designed to be capable of levels of precision similar to conventional oxygen isotope bulk analysis, while maintaining the in situ relationship that is essential for the documentation and interpretation of geological samples. In order to assess SHRIMP-SI instrument performance, oxygen isotopic analyses have been carried out on a suite of zircon reference materials, many of which have been used previously for U-Pb and/or oxygen isotope standardization. We have been able to achieve analytical sessions with measurement stability of better than 0.3 ‰ (95% confidence level).  Analyses of common reference materials (Mud Tank, FC1, Temora, R33) typically yield the expected offsets within 0.1 ‰. 

Publication metrics can be seen on Google Scholar

Journal papers

[33] Rossignol C., Antonio P., Narduzzi F., Rego E., Teixeira L., Souza R., Ávila J.N., Silva M., Lana C., Trindade R., Phillipot P. (in review) Unraveling one billion years of geological evolution of the southeastern Amazonia Craton from detrital zircon analyses. Geoscience Frontiers.

[32] White L., Vasconcelos P., Ubide T., Ávila J.N., Ireland T. (in review) Crystallographic and crystallochemical controls on oxygen isotope analysis of hematite by SIMS. Chemical Geology.

[31] Liu L., Ireland T.R., Holden P., Ávila J.N., Vasconcelos P., Mavrogenes J.(in review) Diverse Pyrite Zoning in the Neoarchean Lamego Banded Iron Formation-Hosted Gold Deposit in the Rio das Velhas Greenstone Belt, Quadrilatero Ferrifero. Contributions to Mineralogy and Petrology.

[30] Chen M., Campbell I.H., Ávila J.N., Huang Z., Sambridge M., Ueno Y., Ireland T.R., Holden P. (in review) Simultaneous fractionation of sulfur dioxide explains quadruple sulfur isotope variations in 2.7 Ga sedimentary pyrites from the Yilgarn Craton, Western Australia. Chemical Geology

[29] Bolhar R., Tappe S., Wilson., Ireland T.R., Ávila J.N., Anhaeusser C. 2021. A petrochronology window into near-surface fluid/rock interaction within Archaean mafic-ultramafic crust: Insights from the 3.25 Ga Stolzburg Complex, Barberton Greenstone Belt. Chemical Geology, in press.

[28] Rossignol C., Rego E.S., Narduzzi F., Teixeira L., Ávila J.N., Silva M., Lana C., Philippot P. 2020. Stratigraphy and geochronological constraints of the Serra Sul diamictites (Carajas Basin, Amazonian Craton, Brazil)Precambrian Research 105981.

[27] Mukherjee I., Deb M., Large R., Halpin J., Meffre S., Ávila J.N., Belousov I. 2020. Pyrite textures, trace elements and sulfur isotope chemistry of Bijaigarh Shales, Vindhyan Basin, India and their ImplicationsMinerals 10:588.

[26] Ávila J.N., Ireland T.R., Holden P., Lanc P., Latimore A., Schram N., Foster J., Williams I.S., Loiselle L., Fu B. 2020. High-precision, high-accuracy oxygen isotope measurements of zircon reference materials with the SHRIMP-SI. Geostandards and Geoanalytical Research 44:85-102.

[25] Ireland T.R., Ávila J.N., Greenwood R., Hicks L.J., Bridges J.C. 2020. Oxygen isotopes and sampling of the Solar SystemIn: Role of sample return in addressing major questions in planetary sciences, M. Anand et al. (Eds.). Space Science Reviews 216:25.

[24] Teles G.S., Chemale Jr. F., Ávila J.N., Ireland T.R., Dias A.N.C., Cruz D.C.F., Constantino C.J.L. 2020. Textural and geochemical investigation of pyrite in Jacobina Basin, São Francisco Craton, Brazil: Implications for paleoenvironmental conditions and Formation of pre-GOE metaconglomerate-hosted Au-(U) depositsGeochimica et Cosmochimica Acta 273: 331-353.

[23] Heck P.R., Greer J., Kööp L., Trappitsch R., Gyngard F., Busemann H., Maden C., Ávila J.N., Davis A.M., Wieler R. 2020. Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide. Proceedings of the National Academy of Sciences, 201904573.

[22] Monteiro H.S., Vasconcelos P.M., Farley K.A., Ávila J.N., Miller H.B.D., Holden P., Ireland T.R. 2020. Protocols for in situ measurement of oxygen isotopes in goethite by ion microprobe. Chemical Geology 553: 119436.

[21] Rajkakati M., Bhowmik S.K., Aob A., Ireland T.R., Ávila J.N., Clarke G.L., Bhandari A., Aitchison J.C. 2019. Thermal history of Early Jurassic eclogite facies metamorphism in the Nagaland Ophiolite Complex, NE India: Newinsights into pre-Cretaceous subduction channel tectonics within the Neo-Tethys. Lithos 346-347: 105166.

[20] Mukherjee I., Large R., Bull S., Gregory D., Stepanov A., Ávila J.N., Ireland T.R., Corkrey R. 2019. Pyrite trace element and sulphur isotope geochemistry of Paleo-Mesoproterozoic McArthur Basin: Proxy for Oxidative weathering. American Mineralogist 104 (9): 1256-1272.

[19] Dasgupta A., Bhowmik S., Dasgupta S., Ávila J.N., Ireland T.R. 2019. Mesoarchaean Clockwise Metamorphic PT Path from the Western Dharwar Craton. Lithos 342-343:370-390.

[18] Gregory D., Mukherjee I., Olson S., Large R, Danyushevsky L., Stepanov A, Ávila J.N., Cliff J., Ireland T.R., Raiswell R., Olin P., Maslennikov V., Lyons T. 2019. The formation mechanisms of sedimentary pyrite nodules determined by trace element and sulfur isotope microanalysis. Geochimica et Cosmochimica Acta 259:53-68.

[17] Timmerman S., Yeow H., Honda M., Howell D., Lynton Jaques A., Krebs M., Woodland S., Pearson D., Ávila J.N., Ireland T.R. 2019. U-Th/He systematics of fluid-rich ‘fibrous’ diamonds–Evidence for pre-and syn-kimberlite eruption ages. Chemical Geology 515:22-36.

[16] Philippot P., Ávila J.N., Killingsworth B.A., Tessalina S., Baton F., Caquineau T., Muller E., Pecoits E., Cartigny P., Lalonde S.V., Ireland T.R., Thomazo C., van Kranendonk M.J., Busigny V. 2018. Globally asynchronous sulphur isotope signals require re-definition of the Great Oxidation Event. Nature Communications 9: 2245.

[15] Rielli A., Tomkins A.G., Nebel O., Raveggi M., Jeon H., Martin L., Ávila J.N. 2018. Sulfur isotope and PGE systematics of metasomatised mantle wedge. Earth and Planetary Science Letters, 497: 181-192.

[14] Palke A.C., Wong J., Verdel C., Ávila J.N. 2018. A common origin for Thai/Cambodian rubies and blue and violet sapphires from Yogo Gulch, Montana, USA? American Mineralogist 103: 469-479.

[13] Ireland T.R., Ávila J.N., Lugaro M., Cristallo S., Holden P., Lanc P., Nittler L., Alexander C.M.O'D., Gyngard F., Amari S. 2018. Rare earth element abundances in presolar SiC. Geochimica et Cosmochimica Acta 221, 200-218.

[12] Babinski M., Rapela C.W.,  Ávila J.N (eds). 2016. 50 years of isotope geology in South America. Brazilian Journal of Geology 46.

[11]   Ireland T.R., Schram N., Holden P., Lanc., Ávila J.N., Armstrong R., Amelin Y., Latimore D., Corrigan., Clement S., Foster J.J., Compston W. 2014. Charge-mode electrometer measurements of S-isotopic compositions on SHRIMP-SI. International Journal of Mass Spectrometry 359, 26-37.

[10]   Ávila J.N., Ireland T.R., Gyngard F., Zinner E., Mallmann G., Lugaro M., Holden P., Amari S. 2013. Barium isotopic compositions in stardust SiC grains from the Murchison meteorite: Insights into the stellar origins of large SiC grains. Geochimica et Cosmochimica Acta 120, 628-647.

[09]   Ávila J.N., Ireland T.R., Lugaro M., Gyngard F., Zinner E., Cristallo S., Holden P., Rauscher T. 2013. Europium s-process signature at close-to-solar metallicity in stardust SiC grains from AGB stars. Astrophysical Journal Letters 768, L18 (7p).

[08]   Ávila J.N., Lugaro M., Ireland T.R., Gyngard F., Zinner E., Cristallo S., Holden P., Buntain J., Amari S., Karakas, A.I. 2012. Tungsten isotopic compositions in stardust SiC grains from the Murchison meteorite: Constrains on the s-process in the Hf-Ta-W-Re-Os region. Astrophysical Journal 744, 49 (13p).

[07]   Barredo S., Chemale Jr. F., Marsicano C., Ávila J.N., Ottone E.G., Ramos V.A. 2012. Tectono-sequence stratigraphy and U-Pb zircon ages of the Rincon Blanco depocenter, Northern Cuyo Rift, Argentina. Gondwana Research 21,624-636.

[06]   Mancuso A.C., Chemale F., Barredo S., Ávila J.N., Ottone E.G., Marsicano C. 2010. Age constraints for the northernmost outcrops of the Triassic Cuyana Basin, Argentina. Journal of South American Earth Sciences 30, 97-103.

[05]   Heck P.R., Gyngard F., Ott U., Meier M.M.M., Ávila J.N., Amari S., Zinner E., Lewis R.S., Bauer H., Wieler R. 2009. Interstellar residence times of presolar SiC dust grains from the Murchison Carbonaceous meteorite. Astrophysical Journal 698, 1155-1164.

[04]   Mallmann G., Chemale Jr. F., Ávila J.N., Kawashita K., Armstrong R.A., 2007. Isotope geochemistry and geochronology of the Nico Perez Terrane, Rio de la Plata Craton, Uruguay. Gondwana Research 12, 489-508.

[03]   Ávila J.N., Chemale Jr. F., Mallmann G., Kawashita K., Armstrong R.A., 2006. Combined stratigraphic and isotopic studies of Triassic strata, Cuyo Basin, Argentine Precordillera. Geological Society of America Bulletin 118, 1088-1098.

[02]   Ávila J.N., Chemale Jr. F., Mallmann G., Borba, A.W., Luft, F.F., 2005. Thermal evolution of inverted basins: Constraints from apatite fission track thermochronology in the Cuyo Basin, Argentine Precordillera. Radiation Measurements 39, 603-611.

[01]   Luft F.F., Luft Jr J.L., Chemale Jr F., Vignol-Lelarge M.L.M., Ávila J.N. 2005. Post-Gondwana break-up record constraints from apatite fission track thermochronology in NW Namibia. Radiation Measurements 39, 675-679.