PhD position in Geology at the Department of Geological Sciences in collaboration with the Climate Research School at Stockholm University. Reference number SU 464-13-0003-12. Deadline for applications: March 3, 2012.
How does metamorphic carbon influence long term climate variability?
Orogenesis (mountain building) causes regional metamorphism of sedimentary rocks. During metamorphism of sedimentary rocks, supercritical CO2-bearing hydrous fluid is released. The volume of fluid which can be released from sedimentary rocks is 5 % (mainly H2O) by weight for pelitic sediments and up to 40% (mainly CO2) for carbonate sediments.
Given that pelites comprise 70–80 % of the sedimentary rock mass of approximately 3.2 ´ 1024 g (Garrels and Mackenzie, 1971), we can estimate that the H2O content of sedimentary rocks is 1.1–1.3 ´ 1023 g. This is approximately equivalent to a tenth of the mass of H2O in the Earth’s oceans. Given that carbonates comprise 5–15 % of the sedimentary rock mass (Garrels and Mackenzie, 1971), we can estimate that the CO2 content of sedimentary rocks is 0.7–2.3 ´ 1023 g. This is more than five orders of magnitude greater than the total mass of CO2 in the Earth’s atmosphere. These chemically-bound fluid components are released during metamorphism.
Prograde metamorphic reactions in the lower and middle crust cause extensive and pervasive release of metamorphic fluid leaving comparatively “dry” rocks. The liberated metamorphic fluid is mobile and buoyant with respect to the surrounding rock mass and thus migrates upwards towards the Earth’s surface (Walther and Wood, 1986). Retrograde metamorphic reactions in the middle and upper crust consume some of this mobile fluid. But fluid flow in the middle and upper crust is channeled and uptake of these fluids by retrograde metamorphic reactions is thus spatially limited to deformation zones (fold hinges, shear zones, faults: Graham et al., 1997). The remaining fluid enters surface reservoirs and can thus influence global climate.
The aim of this project is to quantify metamorphic fluid release in the lower and middle crust with metamorphic fluid uptake in the middle and upper crust so as to provide a basis for calculating the metamorphic contribution of water and carbon to Earth’s surface.
The project will focus on the Hercynian and Caledonian mountain building events and will provide a basis for assessing their potential impact on long term climate variability. This study is important because of controversy regarding whether mountain building should be viewed as a net source or sink of atmospheric CO2 (Skelton, 2011).
Classic areas where metamorphic fluid flow has been studied and where crustal sections are exposed will be used in this study. These are in France, New England and Scotland.
Stockholm University Requirements
Applicants must have completed a research degree (e.g. Masters) or university study of 240 hp (4 years), with at least 60 hp (1 year) at the advanced (research) level.
At least 90 hp in Geology or Earth Science and at least 30 hp Math/Physics/Chemistry and/or Biology, depending on the research topic in Geology. At least 60 hp at the advanced level, including an independent project in Geology or Earth Sciences. For some PhD topics in Geology, students with degrees in appropriate Natural Science topics such as Physics, Chemistry, Math or Biology may be admitted.
The basis for selection is the applicant’s ability to succeed at research training. The evaluation of the candidates will be based on the applicant’s theoretical and experimental experience in Geology, written and verbal communication skills in Swedish or English, analytical and creative thinking, ability to take initiative action and work both independently and in collaboration with others. These attributes will be evaluated on the relevance of the applicant’s previous education, university grade records (especially advanced level courses), quality and breadth of the independent project, references, interviews and the letter of intent.
Appointment regulations for research training at Stockholm University are available in Swedish at: www.regelboken.su.se/pub/jsp/polopoly.jsp?d=1031&a=16354 and the Higher Education Board’s handbook for PhD students in both Swedish and English at: http://doktorandhandboken.nu.
Four year PhD position, full time, start date to be negotiated.
Stockholm University strives to be a workplace free from discrimination and gives equal opportunity for all.
For more information about the position, contact Alasdair Skelton, email@example.com, telephone +46-(0)76-770 76 99.
Anqi Lindblom-Ahlm, (SACO) and Liseth Häggberg (Fackförbundet ST), telephone +46-(0)8-16 2000 (switch board) and Gunnar Stenberg (SEKO), telephone +46-(0)70-316 43 41.
Applications must include:
Application form, cover letter of intent, CV, copies of examination certificates and university course records and the contact details of two referees. The following reference number should be cited: SU 464-13-0003-12.
The deadline for applications is March 3, 2012, and they should be sent by e-mail to: strong>firstname.lastname@example.org
or by post to:
Department of Geological Sciences
SE-106 91 STOCKHOLM
Applications sent by e-mail should be in Word or PDF format. Note! Please include the reference number SU 464-13-0003-12 in the message/subject line.