Other symbols are as in Figure, Map of the Curie temperature (580°C isotherm) depth of the Antarctic Plate. A high‐temperature layer at ~100 km depth separates two cold upper mantle layers beneath the Antarctic Peninsula (D‐D′, Figure 5d). Considering that Rayleigh waves at a period of 100 s include average S velocity information down to ~100 km, the resolution maps at 100 s (supporting information Figure S2a) are considered the lower bound of resolution for the Curie isotherm. and career path that can help you find the school that's right for you. [2015] used fundamental‐mode Rayleigh‐wave group velocities from earthquake waveforms, and from Green's functions derived from ambient noise cross correlation between stations, to derive a new 3‐D shear wave velocity model (AN1‐S) for the Antarctic lithosphere based on single‐step surface‐wave tomography. The asthenosphere is the depth in the earth where heat from the core begins to melt the crust. Since the most common upper crustal minerals have a heat production of ~1 μWm−3 [Rudnick and Fountain, 1995; Hasterok and Chapman, 2011], the heat productivity for the upper crust is set to 1 μWm−3. This layer is unlikely to be lithospheric, as ~150 km is generally too thick for young lithosphere. Properties of Rocks, Computational The slow cooling enables high‐temperature anomalies beneath a rift region to be detected for >10 Myr after tectonic activity has ceased. {{courseNav.course.topics.length}} chapters | An et al. The results indicate that the depth of the LAB for the Antarctic Plate is ~60–110 km beneath West Antarctica and oceanic regions, and ~150–250 km beneath East Antarctica, and that the thickest lithosphere (~250 km) is beneath Domes A and C in East Antarctica. pp. Crustal temperatures and surface heat fluxes were calculated from upper mantle temperatures under the assumption of steady state thermal conduction. The horizontal extent of the slab is ~800 km (Figure 10), indicating an average convergence rate of ~20 km/Myr between 10 and ~50 Ma. Previous studies have shown that temperature is the dominant influence on upper mantle (and even lower mantle) seismic velocity, with composition playing a lesser role [e.g., Jordan, 1979; Nolet and Zielhuis, 1994; Sobolev et al., 1996; Goes et al., 2000; Schuberth et al., 2009]. Previous studies have shown that surface wave measurements are able to detect a stalled slab several million years after the end of subduction [e.g., Wang et al., 2013]. It is considered the source region of mid-ocean ridge basalt (MORB). West Antarctica has a young (< ~110 Ma) continental lithosphere that is thinner than the old (>100 Ma) oceanic lithosphere that surrounds East Antarctica. Try refreshing the page, or contact customer support. Therefore, we were unable to consider the effects of melt and fluid on the conversion from velocity to temperature; however, we know that the presence of fluid in the mantle may yield overestimated temperatures. We thank the Associate Editor, Anya M. Reading, and an anonymous reviewer for numerous comments on our companion paper, An et al. It makes up the upper part of the Earth's mantle, and it exists more as a liquid than as a solid, unlike the crust itself. But it avoids melting because the pressure keeps it solid. However, the crustal geology and heat flux of Antarctica are difficult to measure due to widespread ice cover. The resultant LAB model beneath Antarctica is called AN1‐LAB (Figure 6). Seismic waves are important in locating the depth of the asthenosphere. The lithosphere beneath volcanoes and hotspots (supporting information Figure S3) is very thin (~60 km). Mark Hendrix; Graham R. Thompson (24 January 2014). Tomographic filtering of high‐resolution mantle circulation models: Can seismic heterogeneity be explained by temperature alone? The vertical resolution length for a discontinuity in a velocity model should be smaller than the vertical resolution in the velocity model [An, 2012]. Because depth and S velocity are the two primary parameters in the conversion from S velocity to temperature in the upper mantle, the anomaly patterns of seismic‐thermal temperatures at a given depth should be similar to those of S velocities [An et al., 2015] at that depth. Topographic and tectonic features (subduction‐basin‐mountain) in the West Antarctic rift‐Transantarctic Mountains system (Figure 9a) are similar to those of the present‐day Pacific subduction‐North China basin‐Taihang Mountains system (Figure 9b).