Seventy sites were collected from Pliocene to recent lavas in Ecuador between 0.19¿ and 1.1¿S latitude. Lightning affected many of the sites sampled, and the final data set consisted of 51 sites with α95 of 10¿ or less; 21 flows yielded normal directions of magnetization (declination = 354.6¿, inclination = -5¿, α95 = 7.2¿) and 30 yielded reverse (declination = 183.5¿, inclination = 5.6¿, α95 = 5¿). These sites pass a reversal test at a high level. The combined data give a direction of declination = 359.9¿, inclination = -5.4¿, and α95 = 4.2¿, which is just significantly different from the GAD field but is in agreement with a GAD field plus 5% quadrupole field. Mean VGPs are not significantly different from the geographic poles. The ASD for the combined sites is 13.3¿, which is in agreement with model "G." Paleointensity measurements yield values of VADM, which range from 1.39 ¿ 1022 to 22.6 ¿ 1022 Am2. The mean value for the reverse field is 3.2 ¿ 1022 Am2, while for the normal field it is 10.2 ¿ 1022 Am2. The 40Ar/39Ar dates on selected sites show that they are 2.6 Ma and younger. The age dates and magnetic polarity indicate that the Chacana structure is Brunhes/Matuyama in age.