Preliminary fluid geochemical survey in Tete Province and prospective development of geothermics in Mozambique

Geothermal Energy

Science – Society – Technology

Table 3 Chemical and isotopic compositions of considered thermal waters and dissolved gases

Sample	Site	X	Y	Type	Elevation	T	TDS	pH	Eh	δ¹⁸O	δD	delta¹³C_(TDIC)	F⁻	Cl⁻	Br⁻	NO₃⁻	PO₄³⁻	SO₄²⁻	HCO₃⁻	Na⁺	K⁺	Mg²⁺	Ca²⁺	Li	B	Sr	SiO₂	Fe	Mn	Al	Ref
*	Luenha-Zambezi	33.79221	16.39026	mw	108	–	–	–	–	+ 0.21	+ 12.3	-	-	-		-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	nd
1	Nhawóndòc	33.46192	16.00174	ts	158	66	1512	7.9	− 209	-6.79	-44.8	-11.6	5.3	435	0.99	2.9	< 0.10	372	128	363	29	1.5	98	0.34	0.29	2.3	98	14	19	131	nd
2	Tenta	33.44448	16.02411	ts	121	51	1460	8.0	− 323	-6.75	-44.9	-13.0	6.1	442	0.63	0.87	< 0.10	376	85	368	10	0.27	77	0.35	0.29	2.2	112	25	3.0	54	nd
3	Mauira1	34.15315	15.84933	ts	339	42	951	7.8	− 404	-6.78	-42.7	-9.53	22	266	0.89	0.25	< 0.10	66	231	268	21	0.10	8.2	0.32	0.76	0.09	75	609	47	584	nd
4	Niaondive	–	–	ts	–	80	1554	7.8	–	-	-	-	-	436	-	-	-	444	46	414	19	0.97	73	-	-	-	96	-	-	-	[1]

Sample	He	H₂	O₂	N₂	CH₄	CO₂	Ar	δ¹³C(CO₂)	R/Ra_(C)	δ ¹³C(CH₄)	δD(CH₄)
1	0.00097	1.7E−05	0.23	1.1	0.00067	0.030	0.012	− 15.5	0.13
2	0.00008	1.9E−06	0.22	0.82	0.00024	0.024	0.008	− 18.2	0.14
3	0.00130	1.1E−05	0.14	0.75	0.00470	0.029	0.011	− 15.5	0.21	− 59	− 163

Coordinates (X, Y) WGS84 CGS; mw = meteoric water; ts = thermal spring; Elevation in meters; T in °C; Eh in mV; δ¹⁸O and δD as ‰ vs. VSMOW; TDS, F⁻, Cl⁻, Br⁻, NO₃⁻, SO₄²⁻, HCO₃⁻, Na⁺, K⁺, Mg²⁺, Ca²⁺, Li, B, Sr and SiO₂ in mg/L; Fe, Mn and Al in μg/L; Ref: nd = new data, [1] = Martinelli et al., 1995; He, H₂, O₂, N₂, CH₄, CO₂ and Ar mmol/L; δ¹³C in CO₂ and CH₄ as ‰ vs. VPDB; δD in CH₄ as ‰ vs. VSMOW