Table 3. Chemistry of water samples from the PCS and FWS, Hole 991B.

Core, interval (cm)	Tool/Sample	pH	Alk (mM)	Sal (g/kg)	Cl- (mM)	Mg2+ (mM)	Ca2+ (mM)	SO42- (mM)	PO43- (uM)	NH4+ (uM)	H4SiO4 (uM)	K+ (mM)	 Sr2+ (uM)

164-991B-
2P, 40-50	PCS/IW	7.76 	23	37.0 	644	41	6	1	46 	5310 	 758	13	249
2P, 104	FWS/coil	7.79 	4	32.0 	522	49	9	25	0 	980 	 43	10	101

Notes: Alk = alkalinity and Sal = salinity. PCS = pressure core sampler, IW = interstitial water, and FWS = Fisseler Water Sampler.