Table 2.

Interpretations of the amount of melt present in the upper mantle below the East Africa Rift System based on various geophysical techniques.

Reference	Region	Rift setting	Main geophysical method used	Partial melt zone		Amount of melt calculated in upper mantle
				Depth range, km	Width, km	Author range	Mini-mum	Maxi-mum	Implied melt thickness, km
Hammond & Kendall49	Dabbahu Rift, Afar	continent transition	P and S wave velocities and anisotropy	<26–90	c.150	6-≥15%	6%	15%	3.0–9.8
Desissa et al.30	Dabbahu Rift, Afar	continent transition	magnetotellurics	8–36	30	≥13%	6%	15%	≥3.6
Stork et al.56	Dabbahu Rift, Afar	continent transition	P wave velocities	>30-c.75	100–200	3%	2%	6%-11%	c.0.7-c.3.8
Gallacher et al.55	Afar Depression	continent transition	S (Rayleigh) wave imaging	c.20-c.120	c.100	0.3–0.5%	0.3%	6.4%	0.1–5.1
Hammond et al.31	Afar Depression	continent transition	P and S wave velocities	75–200	50–200	—	0.5%	1.5%	0.6–1.9
Rychert et al.20	Afar Depression	continent transition	S to P wave conversion imaging	0–75	50	c.1%			0.8
Gallacher et al.55	Ethiopian Rift-Afar	continental	S wave velocities	c.20-c.120	100–150	0.3–0.6%	0.3%	4.1%	0.2–5.1
Hammond & Kendall49	Main Ethiopian Rift	continental	P and S wave velocities and anisotropy	<35-c.85	c.100	2–7%			0.8–3.9

The minima and maxima are based on graphs and data in refs^49,54,57 and other references in Supplementary Information.