Comment 3 for bug 1720738

Seems like you're possibly having some sort of hardware issue or disk corruption, based on:

[17869.316475] software-center[18119]: segfault at 10220a770 ip 00007f230828b1ee sp 00007ffc7e508e80 error 4 in libgobject-2.0.so.0.4002.0[7f2308272000+4f000]
[21237.072764] dpkg[20849]: segfault at 1034fdec8 ip 000000000040bce0 sp 00007ffc52b14938 error 6 in dpkg[400000+3f000]
[21245.587086] apt-get[18039]: segfault at 1006210f0 ip 00007fdd0ce4ab29 sp 00007ffe28165f60 error 4 in libapt-pkg.so.4.12.0[7fdd0cdd0000+145000]
[21247.502108] apport[20871]: segfault at fffffff8 ip 0000000000545ee0 sp 00007ffc1b7a76e8 error 4 in python3.4[400000+2fa000]

and

Unpacking oxygen-icon-theme (4:4.13.0-0ubuntu1) ...
dpkg-deb (subprocess): decompressing archive member: lzma error: compressed data is corrupt
dpkg-deb: error: subprocess <decompress> returned error exit status 2