Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rayleigh and acoustic gravity waves detection on magnetograms during the
  Japanese Tsunami, 2011   The continuous geomagnetic field survey holds an important potential in
future prevention of tsunami damages, and also, it could be used in tsunami
forecast. In this work, we were able to detected for the first time Rayleigh
and ionospheric acoustic gravity wave propagation in the Z-component of the
geomagnetic field due to the Japanese tsunami, 2011 prior to the tsunami
arrival. The geomagnetic measurements were obtained in the epicentral near and
far-field. Also, these waves were detected within minutes to few hours of the
tsunami arrival. For these reasons, these results are very encouraging, and
confirmed that the geomagnetic field monitoring could play an important role in
the tsunami warning systems, and also, it could provide additional information
in the induced ionospheric wave propagation models due to tsunamis.

5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con