Table 1. Summary of interstitial water sampling and chemistry, ODP Leg 175.

Table 1. Summary of interstitial water sampling and chemistry, ODP Leg 175.


Site	Location (basin)	Depth of deepest IW (mbsf)	Total depth sampled (mbsf)	Total depth sampled by IWs (%)	Depth to SO₄^2–depletion (mbsf)	Maximum alkalinity (mM)	Maximum NH₄⁺(mM)	Comments
1075	Lower Congo	191	201	95	31.40	41.5	6.1	High-resolution to 60 mbsf
1076	Lower Congo	202	204	99	28.20	36.2	9.2
1077	Lower Congo	204	205	100	28.50	36.0	6.2	Hydrate test 100–130 mbsf
1078	Mid-Angola	150	166	90	21.40	86.5	15.8
1079	Mid-Angola	120	121	99	47.60	59.0	12.8	Brine at depth?
1080	Southern Angola	50	52	96	6.20	47.7	13.0	High-resolution, entire hole
1081	Walvis Ridge	441	453	97	62.30	28.8	11.6	Deep penetration site
1082	Walvis	586	601	98	21.35	75.6	27.3	High-resolution 60 mbsf, deep penetration
1083	Walvis	187	201	93	34.60	37.0	8.7
1084	Northern Cape	600	605	99	5.90	171.7	50.4	Second highest alkalinity, NH₄⁺ DSDP/ODP
1085	Mid-Cape	599	604	99	46.10	27.5	5.8	Deep penetration site
1086	Southern Cape	201	206	98	182.10	17.4	2.8
1087	Southern Cape	477	492	97	79.10	31.2	4.9	Deep penetration site

Notes: Sulfate depletion is defined as the shallowest occurrence of SO₄^2– < 1 mM. IW = interstitial water.