Reading Lapita in near Oceania : intertidal and shallow-water pottery scatters, Roviana Lagoon, New Georgia, Solomon Islands

Abstract

Lapita is the name given by archaeologists to a material culture complex distributed from Papua New Guinea to Samoa about 3000 years ago, which marks major economic changes in Near Oceania and the first settlement by humans of Remote Oceania. Those parts of Solomon Islands that lie in Near Oceania, together with Bougainville, comprise a large gap in the recorded distribution of Lapita, which the current research seeks to explain. At Roviana Lagoon, centrally located in this gap, scatters of pottery, stone artefacts, and other stone items are found in shallow water in this sheltered, landlocked lagoon, initially thought to be late derivatives of Lapita. This research seeks method and theory to aid in the interpretation of this type of archaeological record. Intensive littoral survey discovered a wider chronological range of pottery styles than had previously been recorded, including materials attributable directly to the Lapita material culture complex. A study of vessel brokenness and completeness enabled sample evaluation, estimation of a parent population from which the sample derived, assessment of the state of preservation of the sample, and systematic choice of unit of quantification. Studies of wave exposure of collection sites and taphonomic evidence from sherds concluded that the cultural formation process of these sites was stilt house settlement (as found elsewhere in Near Oceania for Lapita) over deeper water than today. Falling relative sea levels and consequent increasing effects of swash-zone processes have resulted in high archaeological visibility and poor state of preservation at Roviana Lagoon. Analysis of ceramic and lithic variability and spatial analysis allowed the construction of a provisional chronology in need of further testing. Indications are that there is good potential to construct a robust, high-resolution ceramic chronology by focussing on carefully controlled surface collection from this sort of location, ceramic seriation and testing/calibration using direct dating by AMS radiocarbon and Thermoluminescence. Data on preservation and archaeological visibility of stilt house settlements along a sheltered emerging coastline allows preservation and visibility for this type of settlement to be modeled elsewhere. When such a model is applied to other areas of the Lapita gap, which are predominantly either less favourable for preservation or less favourable for archaeological visibility, the gap in the distribution of Lapita can be seen to be an area of low probability of detection by archaeologists, meaning there is currently no evidence for absence of settlement in the past, and good reason to think that Lapita was continuously distributed across Near Oceania as a network of stilt village settlement. This finding highlights the need for explicit models of probability of detection to discover or read the Lapita archaeological record. Keywords: pottery; Lapita; formation processes; surface archaeology; tidal archaeology; Oceania