ANOMALY 2 LOCAL UPDATE

It was compiled from satellite, marine, aeromagnetic and ground magnetic surveys (see our acknowledgment of data providers and collaborators). Д®MAG2 is specified as a global 2-arc-minute resolution grid of the anomaly of the magnetic intensity at an altitude of 4 km above mean sea level. Plug-in files for NASA World Wind can be downloaded from GETECH. The stripes on the left of the image are magnetic lineations due to sea-floor spreading. Kursk (Russia) is seen as a strong anomaly in the background. The longest wavelengths (larger than 330 km) were replaced with the latest CHAMP lithospheric field model MF6.ДЇig.1: (click to enlarge) EMAG2 looking north-west at Portugal/Spain from the Atlantic. Interpolation between sparse tracklines in the oceans was improved by directional gridding and extrapolation, based on an oceanic crustal age model. Additional grid and trackline data have been included, both over land and the oceans. As reflected in the name the resolution has been improved from 3 arc minute to 2 arc minute and the altitude has been reduced from 5 km to 4 km above geoid.

ANOMALY 2 LOCAL UPDATE

Distinct patterns and magnetic signatures can be attributed to the formation (seafloor spreading) and destruction (subduction zones) of oceanic crust, the formation of continental crust by accretion of various terranes to cratonic areas and large scale volcanism (both on continents and oceans).Д®MAG2 is a significant update over our first global magnetic anomaly grid, EMAG3, which provided the base grid for the World Digital Magnetic Anomaly Map of the Commission of the World Geological Map. Furthermore, the global magnetic map is useful in science education to illustrate various aspects of Earth evolution such as plate tectonics and crustal interaction with the deep mantle. Magnetic maps are widely used in the geological sciences and in resource exploration. Anomalies trending parallel to the isochrons (lines of equal age) in the oceans reveal the temporal evolution of oceanic crust. Magnetic anomaly maps provide insight into the subsurface structure and composition of the Earth's crust. GIS GeoTIFF versions of EMAG2 included in the product table at the bottom of this page Print map (paper and digital download) of EMAG2 available at BGR Geoshop

Anomaly 2 local