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Annual Report 2014

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Annual Report 2014 1 Front cover: In 2014 CEED scientists published CEED is dedicated to research of a new model for absolute plate motion that re- fundamental importance to the constructs continents in longitude in such a way understanding of our planet, that that large igneous provinces and kimberlites are embraces the dynamics of the positioned above the edges of two stable thermo- chemical piles (Tuzo and Jason) in the deepest plates, the origin of large scale mantle (Torsvik et al., 2014). We show a 410 Ma volcanism, the evolution of climates reconstruction where kimberlites (red star) in and the abrupt demise of life forms. North America (part of Laurussia) are sourced by a plume from Jason whilst Siberian kimber- This ambitious venture will lites are sourced from the northern margin of Tu- hopefully result in a new model zo. To that new continental reconstruction model, that explains how mantle processes Mat Domeier further integrated geological ob- servations and plate tectonic fundamentals and interact with plate tectonics and built the first real plate tectonic model for the trigger massive volcanism and late Paleozoic (Domeier & Torsvik, 2014). As associated environmental and depicted in this 410 Ma reconstruction, that mod- el includes explicitly delineated and meticulously climate changes throughout Earth managed plate boundaries, which allows the full history. spatio-temporal definition of tectonic plates, in- cluding those floored by oceanic lithosphere. This is a significant and radical departure from the conventional approach of pre- Cretaceous palaeogeographic modeling, which continues to functionally operate under the framework of continental drift. Below: From the formal opening of CEED on October 21st 2014. Back cover from the top: 1: Spatter cone and associated lava flows at the Holuhraun eruption, Iceland, 2014. 2: Field work in the Sarek national park, summer 2014. 3: From the CEED Oslo rift field trip to Sletter-Jeløy-Biløy. 2 PRIMARY OBJECTIVE: ACHIEVEMENTS IN 2014 Develop an Earth model that explains 72 publications i international journals, how mantle processes drive plate tecto- including two in Earth-Science Reviews, nics and trigger massive volcanism and four in Geology and four in Science - UNIV ERSI associated environmental and climate PNAS - Nature changes throughout Earth history Around 100 media- and popular science contributions, including the book “Isfritt. SECONDARY OBJECTIVES: Populærvitenskap som angår deg” edited (1) Build a consistent global plate tecto- by Henrik Svensen. Dougal Jerram has numerous TV participations, and Reidar nic model for the past 1100 Ma Trønnes as an expert during news pre- (2) Explore how palaeogeography and sentations of volcanic eruptions in Ice- True Polar Wander have influenced the land. long-term climate system The start (Phase-I) of the Ivar Giæver (3) Develop models that link surface vol- Geomagnetic Laboratory. canism with processes in the deepest mantle 8 seminars and workshops arranged by (4) Develop models that link subduction CEED processes in arcs and collision orogens with the mantle (5) Understand the role of voluminous intrusive and extrusive volcanism on glo- bal climate changes and extinctions in Earth history (6) Develop models for mantle structure, composition and material properties (7) Understand similarities and differen- ces between the Earth and the other ter- restrial planets (8) Develop tools and databases that in- tegrate plate reconstructions with geody- namic and climate modelling 3 Table of contents Objectives & Achievments …………………………. 3 Organization ……………...………………………… 5 Accumulated Nature, PNAS and Science articles…... 6 Director`s comments……………...…..………….…. 7 Scientific results, Deep Earth…………......…. 12 Scientific results, Dynamic Earth………….…. 16 Scientific results, Earth Modeling…………… 22 Scientific results, Earth Crises……………… 24 Scientific results, Earth and Beyond………... 28 Scientific results, Earth Laboratory 32 Media highlights………………………………....…. 34 Appendices…………………………………...…...... 36 4 organization Advisory Board: Centre for Earth Evolution and Dynamics was officially opened March 1st 2013. Our research includes the dynamics of Rob van der Voo (Head, tectonic plates and Earth history, convection in the mantle, Univ. of Michigan) structure of the deep Earth and the origin of plumes, surface Dave Bercovici (Yale) ages and impact cratering on other planets, the origin of large scale volcanism, rapidly changing climates, and the abrupt de- Karin Sigloch (Oxford) mise of life forms. Linda Elkins-Tanton, To ensure that our scientific vision is effectively met, 2014 ac- (Arizona State University) tivities have been carried out within six research themes: Mike Gurnis (CalTech) Deep Earth (Team leader R. Trønnes), Dynamic Earth (Carmen Gaina), Earth Modelling (A. Bull-Aller), Earth Mioara Mandea (CNES, Crises (H.H. Svensen, Earth and Beyond (S. Werner), Earth Paris) Laboratory (P. Doubrovine) Dietmar Muller (Sydney University) Sierd Cloetingh (Utrecht University CEED staff CEED funding 29 Professors/Adjunct Professors/Research As- sociates 12 Postdocs 10 PhD students 3 Tech.Admin. staff members 9 Master students 1 Professor Emerta In total: 54 paid staff members from 15 countries 5 Accumulated CEED Nature, PNAS and Science articles Articles 1. Conrad, C.P., Steinberger, B., Torsvik, T.H. 2013. Stability of active mantle upwelling revealed by net characteristics of plate tectonics. Nature, 498, 479- 482. 2. Conrad, C.P., Steinberger, B., Torsvik, T.H. 2013. Nature , 503.(E4) – Reply. 3. Torsvik, T.H., Amundsen, H., Hartz, E.H., Corfu, F., Kusznir, N., Gaina, C., Du- brovin, P., Steinberger, B., Ashwal, L.D., Jamtveit, B. 2013. A Precambrian micro- continent in the Indian Ocean. Nature Geoscience, 6, 223- 227. 4. Hasenclever, J., Theissen-Krah, S., Rüpke, L.H., Morgan, J.P., Iyer, K.H., Petersen, S., Devey, C.W. 2014. Hybrid shallow on-axis and deep off-axis hydrothermal circula- tion at fast-spreading ridges. Nature, 508, 508-512. 5. Torsvik, T.H., Van Der Voo, R., Doubrovine, P.V., Burke, K., Steinberger, B., Ash- wal, L.D., Trønnes, R.G., Webb, S.J., Bull, A.L. 2014. Deep mantle structure as a re- ference frame for movements in and on the Earth. Proceedings of the National Acade- my of Sciences of the United States of America, 111, 8735-8740. 6. Van Der Meer, D.G.; Zeebe, R.E.; Van Hinsbergen, D.; Sluijs, A.; Spakman, W., Tors- vik, T.H. 2014. Plate tectonic controls on atmospheric CO2 levels since the Triassic. Proceedings of the National Academy of Science of the United States of America, 111, 4380-4385. 7. Werner, S.C., Ody, A., Poulet, F. 2014. The source crater of martian shergottite meteo- rites. Science, 343, 1343-1346. News and Views 1. Buiter, S. 2014. How plumes help to break plates. Nature, 513, 36-37. Figure (left): To- pography and bathymetry of the Afar Region. From Buiter, S. 2014. How plu- mes help to break plates. Na- ture, 513, 36-37. 6 Director`s comments 2014 was a very dynamic year for CEED and curiosity-driven research elucidating the origin of meteorites from other planets and the links between the Earth’s atmosphere- lithosphere and deep Earth processes was reported in many significant journal articles. Compared with our start-up year (2013) we increased the number of publications by more than 50% — but more importantly — CEED published four articles in the prestigious Na- ture, PNAS and Science magazines. The Science paper — The source crater of martian sher- gottite meteorites (Werner et al.) — received media attention world-wide, and although me- teorites from Mars have been known for several decades, the authors were for the first time able to identify the exact source crater for shergottites, the largest group of Martian meteor- ites. The source region (Mojave) was impacted about 3 million years ago by a medium-size body and ejected rock fragments ended their long space journey at the Earth’s surface a few thousand years ago. CEEDs 10-year mis- sion is to develop an Earth model that ex- plains how mantle pro- cesses drive/interact with plate tectonics, and trigger massive volcanism and asso- ciated environmental and climate changes throughout Earth his- tory. The Earth’s lower mantle is dominated by two antipodal large low shear-wave veloc- ity provinces (LLSVPs) beneath Af- rica (Tuzo) and the Pa- cific (Jason). These dominate the elevated regions of the residual geoid, and a driving CEED hypothesis is that their margins (plume generation zones, PGZs) are the principal source regions for many hotspots and most large igneous provinces (LIPs) and kimberlites (the diamond elevators). We further hypothesise that the Earth has been in a stable degree-2 mode since the Pangea supercontinent formed about 320 million years ago. Stability of Tu- zo and Jason before Pangea is difficult to test with plate reconstructions because the paleo- geography, the longitudinal positions of continents, and estimates of true polar wander (rotation of the Earth’s lithosphere and mantle with respect to the spin axis) have been un- certain. However, in 2014 we demonstrated for the first time that a geologically reasonable model that reconstructs continents in longitude in such a way that LIPs and kimberlites are 7 Director`s comments positioned above the PGZs at the times of their formation can be successfully defined for the entire Phanerozoic. Our reconstructions (see front page picture) comply with known geological and tectonic constraints (opening and closure of oceans, mountain building, and more), and the model requires that Tuzo and
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