Carolina Raquel Lithgow-Bertelloni | |
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Born | |
Alma mater | University of California, Berkeley |
Scientific career | |
Thesis | The history and dynamics of plate motions (1994) |
Carolina Raquel Lithgow-Bertelloni is a geophysicist known for her research on the role of subsurface processes in shaping the Earth. She was elected a fellow of the American Geophysical Union in 2021.
Lithgow-Bertelloni has a B.Sc. from the University of Puerto Rico (1987) and earned her Ph.D. from the University of California, Berkeley in 1994. [1] Following her Ph.D., Lithgow-Bertelloni held positions at Universität Göttingen, Georgia Tech, Carnegie Institution of Washington before becoming an assistant professor at the University of Michigan in 1997, where she remained until 2011. She subsequently held multiple positions at University College London, Roma Tre University, and Carnegie Institute of Washington. In 2018, Lithgow-Bertelloni became the Louis B. and Martha B. Slichter Endowed Chair in Geosciences at the University of California, Los Angeles. [1]
The research done by Lithgow-Bertelloni combines planetary science and geophysics. She is particularly interested in how processes below the surface, e.g., in the mantle, drive processes occurring on Earth's surface. Her research includes investigations into the movement of tectonic plates, [2] particularly in the geological past. [3] [4] She has examined processes that contribute to variability in plate motion including mineralogy in the subsurface [5] [6] and chemical heterogeneity in the mantle. [7] Her research has contributed to our understanding of the early history of the Hawaiian-Emperor seamount chain [8] and the role of changes in viscosity in establishing a boundary in the mantle at one megameter below the Earth's surface. [9] [10] Lithgow-Bertelloni has also described the movement of oceanic plates, potentially distinct from the movement of land masses, over geologic time. [11] [12]
Lithgow-Bertelloni's sister, Anna M. Lithgow-Bertelloni, is also a scientist and works on natural products from marine organisms, one of which may aid in fighting against SARS-CoV-2. [16]
Lithgow-Bertelloni resides in Santa Monica, California.
Plate tectonics is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by geoscientists after seafloor spreading was validated in the mid-to-late 1960s.
The East African Rift (EAR) or East African Rift System (EARS) is an active continental rift zone in East Africa. The EAR began developing around the onset of the Miocene, 22–25 million years ago. It was formerly considered to be part of a larger Great Rift Valley that extended north to Asia Minor.
The African superswell is a region including the Southern and Eastern African plateaus and the Southeastern Atlantic basin where exceptional tectonic uplift has occurred, resulting in terrain much higher than its surroundings. The average elevation of cratons is about 400–500 meters above sea level. Southern Africa exceeds these elevations by more than 500 m, and stands at over 1 km above sea level. The Southern and Eastern African plateaus show similar uplift histories, allowing them to be considered as one topographic unit. When considered this way, the swell is one of the largest topographic anomalies observed on any continent, and spans an area of over 10 million km2. Uplift extends beyond the continents into the Atlantic Ocean, where extremely shallow ocean depths are visible through bathymetric survey. The region can indeed be considered as one large swell because the bathymetric anomaly to the southwest of Africa is on the same order as the topographic anomaly of the plateaus.
Mantle convection is the very slow creep of Earth's solid silicate mantle as convection currents carry heat from the interior to the planet's surface. Mantle convection causes tectonic plates to move around the Earth's surface.
Meiji Seamount, named after Emperor Meiji, the 122nd Emperor of Japan, is the oldest seamount in the Hawaiian-Emperor seamount chain, with an estimated age of 82 million years. It lies at the northernmost end of the chain, lies off the coast of the Kamchatka Peninsula, and is perched at the outer slope of the Kuril–Kamchatka Trench. Like the rest of the Emperor seamounts, it was formed by the Hawaii hotspot volcanism, grew to become an island, and has since subsided to below sea level, all while being carried first north and now northwest by the motion of the Pacific Plate. Meiji Seamount is thus an example of a particular type of seamount known as a guyot, and some publications refer to it as Meiji Guyot.
Pyrolite is a term used to characterize a model composition of the Earth's mantle. This model is based on that a pyrolite source can produce the Mid-Ocean Ridge Basalt by partial melting. It was first proposed by Ted Ringwood (1962) as being 1 part basalt and 4 parts harzburgite, but later was revised to being 1 part tholeiitic basalt and 3 parts dunite. The term is derived from the mineral names PYR-oxene and OL-ivine. However, whether pyrolite is representative of the Earth's mantle remains debated.
The term dynamic topography is used in geodynamics to refer the elevation differences caused by the flow within Earth's mantle.
The Society hotspot is a volcanic hotspot in the south Pacific Ocean which is responsible for the formation of the Society Islands, an archipelago of fourteen volcanic islands and atolls spanning around 720 kilometres (450 mi) of the ocean which formed between 4.5 and <1 Ma.
Slab pull is a geophysical mechanism whereby the cooling and subsequent densifying of a subducting tectonic plate produces a downward force along the rest of the plate. In 1975 Forsyth and Uyeda used the inverse theory method to show that, of the many forces likely to be driving plate motion, slab pull was the strongest. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at oceanic trenches. This force and slab suction account for almost all of the force driving plate tectonics. The ridge push at rifts contributes only 5 to 10%.
Carmen Gaina is the Director of the Centre for Earth Evolution and Dynamics (CEED) a Norwegian Centre of Excellence hosted at the Department of Geosciences, University of Oslo, Norway.
Slab suction is one of the four main forces that drive plate tectonics. It creates a force that pulls down plates as they are subducting and speeds up their movement, creating larger amounts of displacement.
The Darwin Rise is a broad triangular region in the north central Pacific Ocean where there is a concentration of atolls.
Silicate perovskite is either (Mg,Fe)SiO3 or CaSiO3 when arranged in a perovskite structure. Silicate perovskites are not stable at Earth's surface, and mainly exist in the lower part of Earth's mantle, between about 670 and 2,700 km depth. They are thought to form the main mineral phases, together with ferropericlase.
The evolution of tectonophysics is closely linked to the history of the continental drift and plate tectonics hypotheses. The continental drift/ Airy-Heiskanen isostasy hypothesis had many flaws and scarce data. The fixist/ Pratt-Hayford isostasy, the contracting Earth and the expanding Earth concepts had many flaws as well.
A superswell is a large area of anomalously high topography and shallow ocean regions. These areas of anomalous topography are byproducts of large upwelling of mantle material from the core–mantle boundary, referred to as superplumes. Two present day superswells have been identified: the African superswell and the South Pacific superswell. In addition to these, the Darwin Rise in the south central Pacific Ocean is thought to be a paleosuperswell, showing evidence of being uplifted compared to surrounding ancient ocean topography.
Marine geophysics is the scientific discipline that employs methods of geophysics to study the world's ocean basins and continental margins, particularly the solid earth beneath the ocean. It shares objectives with marine geology, which uses sedimentological, paleontological, and geochemical methods. Marine geophysical data analyses led to the theories of seafloor spreading and plate tectonics.
Karen Fischer is an American seismologist known for her research on the structure of Earth's mantle, its lithosphere, and how subduction zones change over geologic history.
Joann Stock is a professor at California Institute of Technology known for her research into plate tectonics, particularly on changes in plate boundaries over geological time.
Richard G. Gordon is an American geophysicist, known for his research on global tectonics, including global plate motions and palaeomagnetism. He is noteworthy for leading two global plate motion projects: NUVEL and MORVEL. In the geosciences, NUVEL and MORVEL are standard models for global plate motions.
David A. Bercovici is an American geophysicist. He is primarily known for his theoretical explanations of why planet Earth has plate tectonics. He is also known for his development of models of how the Earth's mantle recycles and stores water and how such hydrological processes are involved in Earth's geochemical history.