TABLE 4.

Predictions of methanogenesis-to-sulfate reduction ratio (r) as a function of sulfate or chloride in sediments

Ion	μg · cm−3	Log μg · cm−3	k	Log r0a	Log rb	r
Sulfate	200	2.31	1.57	3.85	0	1.00
	9,000	3.95	1.57	3.85	−2.35	<0.01
Chloride	150	2.17	1.59	3.30	−0.10	1.25
	8,500	3.93	1.59	3.30	−2.94	<0.01

^aDetermined from the expression log r (log μg of SO₄²⁻ or Cl⁻·cm⁻³)·k using values of log [SO₄⁻] or [Cl⁻] and log r in Fig. 2.

^bDetermined from the expression log r₀ − (log μg of SO₄²⁻ or Cl⁻·cm⁻³) ·k.