Programme Schedule


Plenary Lectures

Prof. Trond H. Torsvik, Norway
India: A journey in time and space

India: A journey in time and space
Trond H. Torsvik (email:
Centre for Earth Evolution and Dynamics (CEED), University of Oslo, 0315 Oslo, Norway

India's journey in time and space can be described in variable detail for the past one billion years. It was once located along the western margin of the Rodinia supercontinent but break-up details and the Late Neoproterozoic-Cambrian formation of Gondwana is complicated by the fact that paleomagnetic data exhibit aberrant and unresolved behavior between 600 and 520 Ma. India was located along the margin of Gondwana and later Pangea together with several Tibetan terranes that drifted off India in the Permian but mysteriously joined again in the end-Cenozoic. But long before that time, Madagascar-Seychelles-India drifted off Africa at 170 Ma, probably triggered by a deep plume sourcing the Karoo large igneous province (LIP). A younger 90 Myr Madagascar LIP heralded the separation of India-Seychelles from Madagascar at 84 Ma. That spearheaded a northward-directed acceleration of India until 60 Ma and shortly after the Deccan Traps, which separated Seychelles from India. The India-Asia collision is traditionally assumed to have happened in the Early Eocene but all plate reconstructions put India too far south of Asia at that time. This has resulted in plentiful models where India is extended northward in order to be adjacent to Asia by the Early Eocene. Some therefore maintain that the Himalayan Orogeny is best divided into two phases, a first phase of collision of a microcontinent to the north of India at 50 Ma, and a second and more substantial India-Asia collision, starting at 25-20 Ma and which has continued until present day.

Prof. Binod Sreenivasan, India
Role of core-mantle interaction in the geodynamo

Role of core-mantle interaction in the geodynamo
Binod Sreenivasan

The Earth's magnetic field is generated by a dynamo in its fluid outer core, which convects in response to non-uniform heat flow imposed by the mantle. Several observations point to lower-mantle effects on the geodynamo: the high-latitude concentrations of magnetic flux that make up the main dipole field have been found to be relatively stable during the historical period, changes in the frequency of polarity reversals may be correlated to changes in the heat flux at the core-mantle boundary (CMB), and secular variation in the Pacific is weak. Numerical dynamo simulations and laboraory experiments have provided insights into the response of the Earth's field to the inhomogeneity in CMB heat flux. Recent studies indicate that a large variation in CMB heat flux would result in an east-west dichotomy in core convection. This might in turn contribute to the seismic anisotropy of the inner core. In this talk, I shall focus on the role of thermal core-mantle coupling in the geodynamo.

Prof. Christine Thomas, Germany
Seismic structures above and below the core mantle boundary

Seismic structures near the core-mantle boundary

Christine Thomas
Institut für Geophysik
Westfälische Wilhelms Universität Münster

In recent years, seismology has provided increasingly detailed images of the interior of the Earth, especially since the onset of the deployment of temporary seismic arrays: Seismic tomography has revealed that some slabs descend into the lower mantle while others seem to stagnate at the mantle transition zone and hot upwellings also seem to show complex behaviour. Topography of seismic discontinuities can provide information the dynamics of the mantle but also on the mineralogy of the Earth's mantle. The region deep in the Earth, the D" layer (the lowest 200-400 km of the Earth's mantle) and core-mantle boundary region, has been studied extensively, revealing more and more complex features for which several hypotheses to explain them have been brought forward. The observed structures in the D" region and the lowermost mantle could for example be partly due to the post-perovskite phase transition but other causes are still discussed while the origin of the large low seismic velocity regions (LLSVP) is still debated. The presence of anisotropy, ultra-low velocity regions as well as scatterers may also shed more light on mineralogy and dynamics of the mantle. Other interesting observations include the topography of the core-mantle boundary and possible detections a layer just beneath the core-mantle boundary. In this presentation we will review some of these observations from above and below the core-mantle boundary region and their connection to dynamics and mineralogy of the Earth's mantle and core. The different hypotheses for causing these structure will be discussed and compared to seismic observations including as much information of the seismic waves as possible.

IAGA Shen Kuo Medal Lecture

Jay Johnson, USA From Microphysics to System Science: Different Approaches to Understanding Dynamics from the Sun to Saturn