  Electron spin qubits are a promising platform for quantum computation.
Environmental noise impedes coherent operations by limiting the qubit
relaxation ($T_1$) and dephasing ($T_{\phi}$) times. There are multiple sources
of such noise, which makes it important to devise experimental techniques that
can detect the spatial locations of these sources and determine the type of
source. In this paper, we propose that anisotropy in $T_1$ and $T_{\phi}$ with
respect to the direction of the applied magnetic field can reveal much about
these aspects of the noise. We investigate the anisotropy patterns of charge
noise, evanescent-wave Johnson noise, and hyperfine noise in hypothetical
devices. It is necessary to have a rather well-characterized sample to get the
maximum benefit from this technique. The general anisotropy patterns are
elucidated. We calculate the expected anisotropy for a particular model of a
Si/SiGe quantum dot device.
