Dr Sarah Sherlock
Senior Research Fellow
School of Environment, Earth & Ecosystem Sciences
Biography
Professional biography
I hold a permanent Faculty position (Senior Research Fellow) in the Department of Earth and Environmental Sciences here at the Open University, and lead the the Ar-Ar and Noble Gas Research Group and Laboratory. I am also the current Director of STEM Postgraduate Research and have been awarded the status of UKCGE Recognised Research Supervisor, for which I am a scheme reviewer. I am also on the editorial board of the Journal of Petrology, and I am an Executive Editor of Geological Magazine.
My research is argon-centric and entirely laser-based; my interests mainly lie within the realm of technique development and application, as a means to extracting information about processes or events that generally resist arrest when it comes to conventional bulk sampling methods.
My current preoccupation is to find new ways in which we can increase the spatial resolution of Ar/Ar laserprobe dating to extract new information from rocks and minerals. Through this I and colleagues are investigating the diffusion mechanisms of argon in feldpsars, understanding the behaviour of argon durinbg friction melting, the uptake of excess argon in mudrocks and their attendant strain-fringes, the timing of fluid-rock interaction through dating authigenic alkali feldspars, dating meteorite impact craters, the behaviour of argon in volcanic glasses, and most recently in basalts. All using Ar/Ar laserprobe methods.
I also foster collaborative and commercial Ar/Ar dating opportunities with collaborators and clients in the UK and Ireland, many European countries, North and South America, Asia and Australia. I welcome any enquiries about potential collaborations or commercial arrangements, please get in touch if you think Ar/Ar geochronology can solve your scientific problem. I am heading up Earth Science Solutions, a 'one stop shop' providing Ar/Ar dating, sample preparation - rock crushing/cutting and a full range of thin and polished section manufacture, with the added bonus of chemical analysis, we will even collect the samples and charactrise them. A link to the ESS promo material will be here soon.
Projects
Timing of volcanism and intrusive activity in and around the Faroe Islands (SE-09-019-SS)
Alison Halton's PhD work has identified that the present Ar/Ar dating of the Beinsvord Formation in the FIBG is erroneous due to excess argon, sub-microscopic alteration, zeolites, high and variable thermal gradients, and her careful work has determined that this formation erupted in less than 2 Myr, not the commonly accepted 4 Myr. There are only two single age points in the overlying Malinstindur and Enni Formations, and these are used to correlate between Faroe Islands, offshore and Greenland, and important for understanding petroleum reservoir timing and characteristics. Here, Alison will appkly the same methodology to these two formations and form a complete eruption history of the majority of the FIBG.
A new model for argon exchange in natural minerals (SE-12-123-SS)
Pilot data by the PI indicates that the behaviour of the K-Ar system in micas is far from ideal (as determined by theory). The proposed project is to build on the pilot data and to determine if crystal chemical control and/or microstructure can give rise to the measured patchy argon loss. Pilot data from a different study, also by the PI, has identified that micas lose argon at their margins, preferentially where grain boundary triple junctions occur, and the uptake of excess argon appears to be controlled by whichever mineral species is adjacent to the mica. These final two points have hitherto yet to be identified in the published literature.
Publications
Journal Article
Almacık Complex-an exhumed lower to middle crust in northwest Anatolia (2023)
Late Paleocene – Middle Eocene magmatic flare-up in western Anatolia (2022)
The 40Ar–39Ar dating and geochemistry of the Carpathian C1 obsidians (Zemplín, Slovakia) (2021)
A Middle Eocene lowland humid subtropical “Shangri-La” ecosystem in central Tibet (2020)
İzmir‐Ankara suture as a Triassic to Cretaceous plate boundary – data from central Anatolia (2020)
Uplift, Climate and Biotic Changes at the Eocene-Oligocene Transition in Southeast Tibet (2019)
Caledonian metamorphism of metasediments from Franz Josef Land (2019)
Recycling Argon through Metamorphic Reactions: the Record in Symplectites (2018)
Geology of Tindfjallajökull volcano, Iceland (2018)
Argon redistribution during a metamorphic cycle: Consequences for determining cooling rates (2016)
Forests of the tropical eastern Andean flank during the middle pleistocene (2014)
A simple method for in situ U-Th-He dating (2012)
Partitioning of excess argon between alkali feldspars and glass in a young volcanic system (2011)
New Ar-Ar ages of southern Indian kimberlites and a lamproite and their geochemical evolution (2011)
40Ar/39Ar dating of oil generation and migration at complex continental margins (2010)
A laser probe 40Ar /39Ar and INAA investigation of four Apollo granulitic breccias (2008)
First field evidence of southward ductile flow of Asian crust beneath southern Tibet (2007)
Re-evaluating the age of the Haughton impact event (2005)
Dating of multistage fluid flow in sandstones (2005)
Fingerprinting polyorogenic detritus using the 40Ar/39Ar ultraviolet laser microprobe (2002)
Presentation / Conference
Hydrothermal alteration in the Frankenstein gabbro Martian analogue: first models (2020)
Noble gas behaviour in pumice: Implications for volcanic degassing (2020)
The Frankenstein Gabbro (Odenwald, Germany): A New Analogue for Martian Hydrothermal Systems (2019)
Noble gases: A tool to track the degassing of active volcanic systems (2017)
Understanding the degassing of young volcanic systems using noble gases (2017)
Containers, sensors and samples to understand desert weathering (2015)
Metamorphic rocks seek meaningful cooling rates: new views from muscovite 40Ar/39Ar dating (2012)
