19). Decreasing cell concentrations after drilling has also been observed in other CORKs [Juan de Fuca ridge flank; (
21)] and groundwater well systems (
5)], low cell counts likely indicate that the North Pond system had recovered from drilling and that the 2017 fluids (and resulting data) are the best representation of microbial activity in the cold, oxic crustal subseafloor aquifer to date.
Table 1 North Pond CORK fluids and bottom water values for cell enumeration, dissolved inorganic carbon (DIC), and dissolved organic carbon (DOC) from 2017 samples collected for this study.
Additional geochemistry (oxygen, nitrate, and pH) reproduced from (
5) also collected in 2017. Ammonium concentrations were all below detection (