#Abstract
Improving upon standard earthquake detection techniques, specifically in areas where events are likely induced by fluid injection, can be useful in characterizing and monitoring the state of a geothermal resource with time. Using an earthquake catalog of 637 events occurring between 1 January and 18 November 2015 as our initial dataset, we implemented a matched filtering routine for the Mighty River Power (MRP) geothermal fields at Rotokawa and Ngatamariki, North Island, New Zealand. We detected nearly 21,000 additional events across both geothermal fields, a roughly 30-fold increase from the original catalog. On average, each of the 637 template events detected 45 additional events throughout the study period, with a maximum number of additional detections for a single template of 359. Cumulative detection rates for all template events, in general, do not mimic large scale changes in injection rates within the fields however we do see some indications of an increase in detection rate associated with power plant shutdown at Ngatamariki. Locations of detected events follow established patterns of historic seismicity at both Ngatamariki and Rotokawa, with one large cluster of events in the southeastern portion of Rotokawa and two distinct clusters in the North and South of Ngatamariki.