The Early and Middle Bronze Age Settlement at Koimisis, Therasia: Periods of Habitation and Architecture

Abstract

The study of the history of the first excavations on prehistoric Therasia in the nineteenth century, which were carried out in the context of contemporary scientific interest in the volcanic eruptions of Santorini, has led to the systematic archaeological investigation of the island from 2007 onwards. The intensive archaeological surface survey, the geological survey of the geological structure and palaeotopography of Therasia, and geophysical investigations, undertaken in conjunction with the ongoing excavation of the prehistoric settlement at the site of Panaghia Koimisis at the southern end of modern Therasia, have created the conditions for a more comprehensive approach to the archaeological landscape of the island. Based on the results from the excavation trenches in the south and south-east terraces of the Koimisis hill, which have been excavated down to the virgin soil, we present findings on the organisation, architecture and habitation phases of the Koimisis settlement. The site emerges as an important settlement located on the imposing hilltop rising on the west side of the pre-eruption Santorini caldera in the Early Bronze Age, with a long period of habitation to the end of the Middle Cycladic period, when it was definitively abandoned. The excavation of the settlement provides new information on its architecture and spatial organisation during the Early and Middle Bronze Age, completing the picture from Akrotiri, whose early phases are preserved in a piecemeal fashion under the buildings of the Late Cycladic town.

Olive shrub buried on Therasia supports a mid-16th century BCE date for the Thera eruption

“…The Koimisis olive shrub was excavated a few meters south of the present day Monastery of Panaghia Koimisis, at an Early to Middle Bronze Age clifftop settlement 196m above sea level at the edge of the caldera 2 . The site sits on lava flows, dated c. 45,000-25,000 years ago, and the ashes of the Cape Riva eruption of Thera c. 22,000 years ago.…”

“…The eruption of Thera in the Santorini archipelago, Greece, (Fig. 1 a,b), sometime in the 2nd millennium BCE, sealed the spectacular Minoan settlement of Akrotiri and other sites on Thera and Therasia under meters of volcanic debris 1 , 2 . The eruption is thought to have been the largest of the Holocene in terms of volume, and highly explosive, with a Volcanic Explosivity Index (VEI) of 7 3 .…”

“…In this study, we report radiocarbon dates from a second olive (henceforth called the Therasia olive) found during excavations near the present day Monastery of Panaghia Koimisis, on the southern-most tip of the island of Therasia 2 at the western side of the present-day Santorini caldera (Fig. 1 b–f).…”

“…In 2016, a trench was opened in an upper terrace of the hill (trench AB) (Fig. 1 d,e), where the eruption layers were still partially preserved to a maximum depth of around 90 cm 2 . The charred shrub remains were found immediately below the layer of pumice, in between some terraced stones which showed localized burning (Fig.…”

Problems of Dating Spread on Radiocarbon Calibration Curve Plateaus: The 1620–1540 BC Example and the Dating of the Therasia Olive Shrub Samples and Thera Volcanic Eruption

“…The recent publication of radiocarbon dates offering sequences (inner to outer growth segments) from four samples of olive wood from different pieces of the same olive shrub from Therasia in the southern Aegean (Pearson et al 2023; for the archaeological context of the olive shrub, see also Sbonias et al 2020) offers a good case study that highlights and encompasses all aspects of the problems associated with plateau spread for radiocarbon dating-and thus also an opportunity to consider approaches to address this issue. In the Pearson et al (2023) paper the four olive branch samples, 88-3, 88-2, 88-1 and 72-2, are each considered as separate sequences, from inner growth to outer growth (or bark) segments in OxCal, and conclusions are drawn from the modeled age ranges of the last (outer) growth segments-argued to be associated with (killed by), and so relevant to, the dating of the Minoan eruption of the Thera or Santorini volcano.…”