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International Ocean Discovery Program (IODP) Expedition 382 in the Scotia Sea’s Iceberg Alley recovered among the most continuous and highest resolution stratigraphic records in the Southern Ocean near Antarctica spanning the last 3.3 Myr. Sites drilled in Dove Basin (U1536/U1537) have well-resolved magnetostratigraphy and a strong imprint of orbital forcing in their lithostratigraphy. All magnetic reversals of the last 3.3 Myr are identified, providing a robust age model independent of orbital tuning. During the Pleistocene, alternation of terrigenous versus diatomaceous facies shows power in the eccentricity and obliquity frequencies comparable to the amplitude modulation of benthic δ18O records. This suggests that variations in Dove Basin lithostratigraphy during the Pleistocene reflect a similar history as globally integrated ice volume at these frequencies. However, power in the precession frequencies over the entire ∼3.3 Myr record does not match the amplitude modulation of benthic δ18O records, suggesting Dove Basin contains a unique record at these frequencies. Comparing the position of magnetic reversals relative to local facies changes in Dove Basin and the same magnetic reversals relative to benthic δ18O at North Atlantic IODP Site U1308, we demonstrate Dove Basin facies change at different times than benthic δ18O during intervals between ∼3 and 1 Ma. These differences are consistent with precession phase shifts and suggest climate signals with a Southern Hemisphere summer insolation phase were recorded around Antarctica. If Dove Basin lithology reflects local Antarctic ice volume changes, these signals could represent ice sheet precession-paced variations not captured in benthic δ18O during the 41-kyr world.

We study a simple magnetohydrodynamical approach in which hydrodynamics and MHD turbulence are coupled in a shell model, with given dynamo constraints in the large scales. We consider the case of a low Prandtl number fluid for which the inertial range of the velocity field is much wider than that of the magnetic field. Random reversals of the magnetic field are observed and it shown that the magnetic field has a nontrivial evolution--linked to the nature of the hydrodynamics turbulence.

Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally accepted that plate tectonics is the dominant mechanism since 2 billion years ago, but for older periods in the Earth's history, this is still a topic of debate. Plate tectonics cause large-scale horizontal movement, while other mechanisms mainly cause vertical movement. My PhD research has focused on 2.8 to 2.7 billion year old rocks of the Pilbara Craton, Western Australia, and 2.9 to 2.7 billion year old rocks from the Kaapvaal Craton, South Africa. Over 3000 oriented rock cores were taken from geological formations that have formed within ca. 60 million years. Palaeomagnetic tests demonstrate that the magnetization preserved in the rocks is still that from the time of rock formation. This means that the recorded magnetic directions can be translated to a (palaeo)latitude, which is the latitude at which the rocks have formed. The research demonstrates that the latitude of formation of the rocks has changed through time. At ca. 2720 million years ago, the Pilbara Craton changed latitudinal position with a rate of ca. 50 cm per year and shifted some 1600 km in total. This demonstrates that significant horizontal movements occurred as early as 2.7 billion years ago, which supports the arguments of the advocates of the occurrence of plate tectonics in Earth's early history. Additionally, my research has demonstrated that the Earth's magnetic field has been stable since at least 2.8 billion years ago. The character of the ancient field appears to be much like the current field, including the occurrence of geomagnetic reversals, the magnetic intensity, and the amount of secular variation. Some researchers ascribe a stable geomagnetic field to the presence of a solid inner core. If this were true, based on my findings, the Earth's solid inner core would have to be at least 2.8 million years old

Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally accepted that plate tectonics is the dominant mechanism since 2 billion years ago, but for older periods in the Earth's history, this is still a topic of debate. Plate tectonics cause large-scale horizontal movement, while other mechanisms mainly cause vertical movement. My PhD research has focused on 2.8 to 2.7 billion year old rocks of the Pilbara Craton, Western Australia, and 2.9 to 2.7 billion year old rocks from the Kaapvaal Craton, South Africa. Over 3000 oriented rock cores were taken from geological formations that have formed within ca. 60 million years. Palaeomagnetic tests demonstrate that the magnetization preserved in the rocks is still that from the time of rock formation. This means that the recorded magnetic directions can be translated to a (palaeo)latitude, which is the latitude at which the rocks have formed. The research demonstrates that the latitude of formation of the rocks has changed through time. At ca. 2720 million years ago, the Pilbara Craton changed latitudinal position with a rate of ca. 50 cm per year and shifted some 1600 km in total. This demonstrates that significant horizontal movements occurred as early as 2.7 billion years ago, which supports the arguments of the advocates of the occurrence of plate tectonics in Earth's early history. Additionally, my research has demonstrated that the Earth's magnetic field has been stable since at least 2.8 billion years ago. The character of the ancient field appears to be much like the current field, including the occurrence of geomagnetic reversals, the magnetic intensity, and the amount of secular variation. Some researchers ascribe a stable geomagnetic field to the presence of a solid inner core. If this were true, based on my findings, the Earth's solid inner core would have to be at least 2.8 million years old.

Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally accepted that plate tectonics is the dominant mechanism since 2 billion years ago, but for older periods in the Earth's history, this is still a topic of debate. Plate tectonics cause large-scale horizontal movement, while other mechanisms mainly cause vertical movement. My PhD research has focused on 2.8 to 2.7 billion year old rocks of the Pilbara Craton, Western Australia, and 2.9 to 2.7 billion year old rocks from the Kaapvaal Craton, South Africa. Over 3000 oriented rock cores were taken from geological formations that have formed within ca. 60 million years. Palaeomagnetic tests demonstrate that the magnetization preserved in the rocks is still that from the time of rock formation. This means that the recorded magnetic directions can be translated to a (palaeo)latitude, which is the latitude at which the rocks have formed. The research demonstrates that the latitude of formation of the rocks has changed through time. At ca. 2720 million years ago, the Pilbara Craton changed latitudinal position with a rate of ca. 50 cm per year and shifted some 1600 km in total. This demonstrates that significant horizontal movements occurred as early as 2.7 billion years ago, which supports the arguments of the advocates of the occurrence of plate tectonics in Earth's early history. Additionally, my research has demonstrated that the Earth's magnetic field has been stable since at least 2.8 billion years ago. The character of the ancient field appears to be much like the current field, including the occurrence of geomagnetic reversals, the magnetic intensity, and the amount of secular variation. Some researchers ascribe a stable geomagnetic field to the presence of a solid inner core. If this were true, based on my findings, the Earth's solid inner core would have to be at least 2.8 million years old

Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally accepted that plate tectonics is the dominant mechanism since 2 billion years ago, but for older periods in the Earth's history, this is still a topic of debate. Plate tectonics cause large-scale horizontal movement, while other mechanisms mainly cause vertical movement. My PhD research has focused on 2.8 to 2.7 billion year old rocks of the Pilbara Craton, Western Australia, and 2.9 to 2.7 billion year old rocks from the Kaapvaal Craton, South Africa. Over 3000 oriented rock cores were taken from geological formations that have formed within ca. 60 million years. Palaeomagnetic tests demonstrate that the magnetization preserved in the rocks is still that from the time of rock formation. This means that the recorded magnetic directions can be translated to a (palaeo)latitude, which is the latitude at which the rocks have formed. The research demonstrates that the latitude of formation of the rocks has changed through time. At ca. 2720 million years ago, the Pilbara Craton changed latitudinal position with a rate of ca. 50 cm per year and shifted some 1600 km in total. This demonstrates that significant horizontal movements occurred as early as 2.7 billion years ago, which supports the arguments of the advocates of the occurrence of plate tectonics in Earth's early history. Additionally, my research has demonstrated that the Earth's magnetic field has been stable since at least 2.8 billion years ago. The character of the ancient field appears to be much like the current field, including the occurrence of geomagnetic reversals, the magnetic intensity, and the amount of secular variation. Some researchers ascribe a stable geomagnetic field to the presence of a solid inner core. If this were true, based on my findings, the Earth's solid inner core would have to be at least 2.8 million years old.