Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Lava channel formation during the 2001 eruption on Mount Etna: evidence
  for mechanical erosion
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga