The CD-ROM "Magnetic anomaly map of East Asia 1:4,000,000 CD-ROM Version" was published by Geological Survey of Japan in 1996.

This CD-ROM is the second product of the Aeromagnetic Map Compilation Programme of Coordinating Committee for Coastal and Offshore Geoscience Programmes (CCOP), following the "Magnetic Anomaly Map of East Asia", which was published in 1994 by Geological Sutvey of Japan and CCOP.

The objective of this CD-ROM publication is to provide users with gridded digital magnetic anomaly data obtained from the programme and also to give you chances of displaying the map on computers and using it in a digital form.

The following files are included in this CD-ROM:

1. Gridded data files which were used to make "Magnetic Anomaly Map of East Asia",

2. Track line data files corresponding to the data sets that were used in the compilation of the above map.

3. Image data files to show magnetic anomaly data on a computer monitor, including necessary display software.

X, Y values of geographyc co-ordinates are calculated using Lambert azimuthal equal_area projection with the central point at 15 _o N, 120 _oE. A spherical earth with the radius of 6377 km is assumed.

Sheet 1 has an area of 4000 km x 2870 km. Coordimates (X,Y) (in km) of its southwestern and northeastern corners are (-1850, 686) and (2150, 3556), respectively.

Sheet 2 has an area of 3500 km x 3280 km. Coordimates (X,Y) (in km) of its southwestern and northeastern corners are (-2740,-2594) and (760, 686), respectively.

"Magnetic anomaly map of East Asia 1:4,000,000 CD-ROM Version"

Geological Survey of Japan and

Coordinating Committee for Coastal and Offshore Geoscience

Programmes in East and Southeast Asia (CCOP)

Digital Geoscience Map 2 (P-1)

Published by Geological Survey of Japan, 1996

Users can order subsets of data by e-mail .