Methods and systems for flagging events in a time series and evaluating a downhole operation

A method for evaluating a pressure test performed in a borehole formed in a geological formation, comprising:

• i. collecting an unlabeled pressure time series relative to the formation acquired during the pressure test,
• ii. extracting at least one subsequence of predetermined duration from the time series, wherein the subsequence is representative of a buildup phase of the pressure test,
• iii. assigning a label representative of the status of the pressure test based on the at least one extracted subsequence, using at least a predictive function, wherein the predictive function has been determined using a dataset of labelled pressure time series,
• iv. sending a command to a wellsite operating system based on the assigned label.

A system for evaluating a downhole operation performed in a borehole formed in a geological formation, comprising a processing system configured to:

• i. collect an unlabeled time series relative to the geological formation,
• ii. extract at least a subsequence of predetermined duration from the time series,
• iii. assign a label representative of the status of the downhole operation based at least on the extracted subsequence, using at least a predictive function, wherein the predictive function has been determined using a dataset of labeled subsequences of predetermined duration,
• iv. send a command to a wellsite operating system based on the assigned label.