 The exact age of Heart Peaks is not known, but its first volcanic phase occurred during the Neogene period (between 23 and 2.5 million years ago).The variety of volcanic deposits at Heart Peaks indicates that it has a history of producing not only fluid and passive basaltic lava flows, but also more silica-rich trachyte and rhyolitic lavas and explosive eruptions.Phreatic breccias are found at the volcano, providing evidence that phreatic eruptions have occurred at least once throughout its eruptive history.