Variatons of the geomagnetic field
Neotectonic and geodynamical research
Rock magnetism & environmental magnetism
of the geomagnetic field
Age and timing
of records of geomagnetic variations
timing of records of geomagnetic variations
variation before, during and after a Superchron and implications for the
geodynamo with an emphasis on the Permo-Carboniferous Superchron as well
as on the Archaean and Proterozoic. Excellent records of secular variation
were recorded in Permian red beds, and the project of Marcela Haldan aims
at significantly extending records of SV in these sediments, both during
and after the Permian superchron.
Marcela Haldan, Cor Langereis, Mark Dekkers, Andy Biggin
studies in Turkey
record of sites of known age in Turkey allows establishing a master curve
for the region that can subsequently be used for dating purposes. Further
it consists valuable input for global field models. In a later stage archeointensity
information will be gathered as well to further refine our description
of the Earth’s magnetic field in the recent past.
Pinar Ertepinar, Cor Langereis, Andy Biggin
the ancient intensity, the paleointensity, of the Earth’s magnetic field
from lavas is constituting a major challenge. The project involves comparing
several paleointensity determination techniques, including the ‘multispecimen
method’ on synthetic samples and historical lavas.
Lennart de Groot, Mark Dekkers, Andy Biggin
and Astronomical Polarity Time Scales
of astronomical polarity time scales is crucial in tectonostratigraphic
and paleogeographic analyses. Integrated magneto-bio-cyclostratigraphy
of late Neogene land sections in the (circum) Mediterranean, and the construction
of astronomical polarity time scales will be used for understanding the
neotectonics and resulting sedimentary systems and their time-dependent
Krijgsman, Cor Langereis and
on the Late Miocene evolution of the Mediterranean - Atlantic - Indian
Ocean Gateways establishes high-resolution time frames for the sedimentary
sequences of the gateway basins with special emphasis on the timing of
their restriction and closure. Paleogeographic reconstructions will aid
in decyphering the closure mechanism.
Wout Krijgsman, Silja Hüsing
Miocene to Pliocene evolution
of the western Paratethys (Transylvanian and Pannonian basins) and spatial-temporal
connections between Miocene semi-isolated basins
A high-resolution chronologic
framework is aimed at for the Neogene sediments deposited in the western
Paratethys area focussing on the middle and upper Miocene of the Pannonian
and Transylvanian basins. n tectono- stratigraphic studies to unravel This
allows unraveling the tectono-stratigraphic evolution of the Pannonian-Carpathian
orogenic system and a correlation of events between the Paratethys and
Arjan de Leeuw, Wout Krijgsman
Late Triassic extinction(s):
a singular event or multiple ecological avalanches ?
Understanding past biotic crises
has passed beyond pure academic interest: the current anthropogenic-induced
loss of biodiversity rivals mass-extinctions in the geological past. The
project aims at providing a high-resolution time frame for the Late Triassic
in order to unravel cause and consequence of the Triassic-Jurassic mass
Martijn Deenen, Wout Krijgsman
and time scales, and connections with the Mediterranan
The northward plate tectonic
motion of the African/Arabian continent during the Neogene (24-0
Myrs ago) has led to the closure
of the Tethys Ocean and created the Paratethys domain: a large endemic
water mass that extended from Austria to Iran, with the Black Sea and Caspian
Sea as actual remnants. The time scale for the Paratethys domain is highly
equivocal and controversial ages exist for many events and geological stage
boundaries, although suitable conditions exist to develop astronomical
polarity time scales.
One of the many key questions
concerns closure and opening of the marine connection(s) between Mediterranean
and Paratethys, and is at present far from understood.
In this project, we aim to
develop a high-resolution astronomical polarity time scale for the
Paratethys with special focus
on the last ~10 Myr of geological history which requires a multi-disciplinary
integrated approach and suitable sedimentary sequences.
Several ongoing projects tackle
this issue, like the Dutch-Russian collaboration on Taman Peninsula (Russia)
and in Azerbaijan. High-resolution (micro)paleontological, palynological/paleoecological,
geochemical (isotopes) and cyclostratigraphic records aim at detailed reconstructions
of the environment and climate history of Eurasia.
Iuliana Vasiliev, Wout Krijgsman, Marius Stoica, Cor Langereis, Katya Grundan,
Ksenia Pavlova. See also Andy Lotter and Wolfram
Kürschner at the Paleoecology
Group at the Department of Biology
and geodynamical research
drifting continents: plate tectonics during Early Earth ?
research on the Pilbara craton (Australia) and the Barberton craton (South
Africa) is carried out to test different models on early Earth tectonism.
It concerns a cooperation with the Utrecht Structural Geology and Tectonics
group (prof. Stan White) and with prof. Maarten de Wit (University of Cape
Town, South Africa). Ar/Ar dating forms an important part of the research
and is done by Jan Wijbrans (Free University, Amsterdam).
Zegers & Cor Langereis
and closure of the Tethys oceans: Mesozoic Cimmerian deformation around
the present-day Black Sea
evolution of the areas surrounding the Black Sea - the North Dobrogea Orogen,
Crimea, the Greater Caucasus and the Turkish Pontides, Anatolides and Taurides
- is complex. Paleomagnetic information constrains the paleolatitude which
in turn helps assessing the veracity of various proposed tectonic scenarios.
Maud Meijers, Cor Langereis, Douwe van Hinsbergen, Randell Stephenson (VU)
constraints on the kinematics of Anatolia
Anatolia is the northernmost extension of the Arabian Plate. It forms a
key area for the study of the collision history of the Arabian and Eurasian
plates. are recorded continuously. Research involves a blend of paleomagnetsm,
structural geological mapping, and interpreting GPS motions.
Ahmet Peynircioglu, Cor Langereis, Douwe van Hinsbergen, Nuretdin Kaymakçi
rate of the Tibetan plateau and its relation to global climate change
and uplift of the Tibetan plateau triggers the onset of Asian monsoons,
and thus generates a major change in global climate. The best-exposed Tertiary
basin of northern Tibet – the Xining basin – is targetted to decipher independently
the tectonic and climatic components of the sedimentary record in response
to Tibetan uplift. Magneto-cyclostratigraphic analysis and a wide array
of paleoenvironmental proxies are being gathered in the basin deposits.
In addition, the exhumation history of adjacent granitic massifs is being
quantified using U-Th/He thermochronology.
Guillaume Dupont-Nivet, Wout Krijgsman, Cor Langereis
magnetism & environmental magnetism
research into the magnetic properties of the various natural magnetic minerals.
Current efforts (Mark Dekkers, Guillaume Dupont-Nivet) utilise very high
pulse magnetic fields (high field pulse laboratory, Toulouse (France))
to constrain the anisotropy constants of hematite and goethite.
and environmental magnetic change around the middle Miocene global climate
change in the Mediterranean
climate changed in the middle Miocene, likely caused by ice sheet expansion
on Antarctica. The response of the Mediterranean sedimentary basins in
terms of environmental change is the aim of this project. The middle Miocene
marls of Monte Corvi (Italy) have yielded a robust astronomical time scale.
Secondly, suitable sections in the Mediterranean and a possible gateway
to the Indian Ocean will be studied.
Silja Huesing, Wout Krijgsman, Mark Dekkers
of paleomagnetic and rock-magnetic data acquisition
magnetometer is interfaced with a robot that allows completely automated
data acquisition of up to 96 samples. Options includes alternating field
demagnetization, ARM and IRM acquisition.
Tom Mullender, Mark Dekkers
in southwestern Turkish basins
developments enable to differentiate remagnetized strata on a rock-magnetic
basis. The method proposed for a Spanish Pyrenean basin is further tested
in several basins in soutwestern Turkey.
Douwe van Hinsbergen, Mark Dekkers
and rock-magnetic methods in paleolitic archeology
homonine and Neanderthaler sites across Europe are being studied with an
array of geophysical and geochemical methods with the aim to improve their
age determination and to trace the evolution of the skills of our ancestors
Mark Sier, Wil Roebroeks, Mark Dekkers, Cor Langereis, Douwe van Hinsbergen
remagnetization and fluid flow
of pervasive remagnetization of the natural remanent magnetization (NRM)
is essential for a correct interpretation of paleomagnetic data and, evidently,
has important geodynamical implications. The research revolves around a
key basin of Cretaceous age in the Pyrenees. The research strategy seeks
to optimise a combination of mineral-magnetic, paleomagnetic and ‘non-magnetic’
methods. The latter methods include thin section and SEM/TEM microscopy
on rocks and magnetic concentrates, determination of the 87Sr/86Sr ratio
from carbonates, determination of smectite/illite ratios, and assessing
scenarios for fluid movement through the rock pile by hydrological modeling.
Gong and Mark Dekkers
a Deutsche Forschungs Gemeinschaft funded Bremen - Amsterdam - Utrecht
- Université de Bordeaux - Southampton Oceanographic Centre - Massachusetts
Institute of Technology graduate college for the training of PhD students.
It aims to progress our understanding of the history of natural variability
of biological and physical processes and their impact on climate and oceans.
The Utrecht paleomagnetism group is involved with the advanced interpretation
of magnetic proxy parameters.
projects are done in conjunction with archeological research (archeomagnetism)
and with NITG (Geological Survey), e.g. on Pleistocene deposits in the
Netherlands and Suriname.
organisatie voor Wetenschappelijk Onderzoek
(Netherlands Organization for Scientific Research)
National Research Centre for Integrated