the fibre-optic cable near the unit, or problems with the electronics due to the high sampling rate.

Visually, stripes can manifest themselves in a variety of ways. Some are visually obvious within the DAS data, such as the stripe that occurs at around $4000$ms in Figure \[fig:stripes\](a). Other occurrences can be more subtle, and therefore more challenging to detect. For example, the stripe could be a change in the second-order structure. Critically such features can make it difficult to carry out further analysis of the data, such as flow rate analysis. For this reason, there is significant interest in being able to detect regions of striping as soon as they occur, so that they can be removed whilst keeping as much of the original signal intact as possible. It is this challenge of dynamically detecting striping regions that motivates the work presented in this article.

[0.8]{} ![Time series plots of DAS amplitude at four different well depths over the same time period: (a) original series; (b) detrended series. The highlighted regions in (a) indicate three examples of striping.[]{data-label="fig:stripes"}](fig1-eps-converted-to.pdf "fig:"){width="104mm"} \[fig:fig1a\]

[0.8]{} ![Time series plots of DAS amplitude at four different well depths over the same time period: (a) original series; 