Geohazard assessment from satellite magnetic data modeling—with examples from the Arctic Margin along the Canada Basin and the Korean Peninsula along 40°N (latitude) parallel

Abstract

Long-wavelength, relative high-amplitude-magnetic anomalies obtained at satellite altitudes have provided an understanding of the nature of the deeper crust of the Earth. We have studied two such long-wavelength anomalies in regions of high stress-one with a large and one with a lower amplitude anomaly. The first feature is on the Canada Basin continental margin in the Northwest and Yukon Territories, Canada (magnetic anomaly range: 19 nT to −6 nT at 350-km altitude). This area is also the focus of significant stress and earthquake activity. We interpret this anomaly and associated tectonic activity with this region's position at or near the fulcrum of the scissors-like opening of the Canada Basin in the mid-Mesozoic Era. The second is a section along the 40• N (latitude) parallel crossing the Korean Peninsula (magnetic anomaly range: <−2 nT to >3 nT at 350-km altitude), where an east-west fracture zone has been proposed to extend from northeastern China, across the Korean Peninsula, Sea of Japan and (Northern) Japan.

Possible correlation between the vertical component of lithospheric magnetic field and continental seismicity

“…By avoiding the difficulties of near-surface data, satellite observations provide a better description of large-scale magnetic profile, making them more suitable for studying regional tectonics and seismicity. Taking advantage of the rapid development of satellite magnetic observations, several recent studies have applied these observations to earthquakes (Taylor et al 2008;von Frese et al 2008).…”

“…Few studies, however, use the new magnetic satellite data or the new LMF models to examine the correlation between satellite LMF and seismicity. Taylor et al (2008) compared the CHAMP scalar magnetic anomalies at an altitude of 350 km with the seismicity of the Korean Peninsula. They found that the zero contour of magnetic anomaly divides the seismicity of the peninsula into high and low parts.…”

“…They found that most epicenters are located near areas with zero B z . These researchers (Taylor et al 2008;von Frese et al 2008;Wei and Yu 2012) reported correlation between seismicity and the satellite magnetic anomaly, but they did not perform a rigorous statistical inspection of this correlation. Furthermore, they attributed the seismicmagnetic correlation to the stress field.…”