Landscape Evolution in Cebu, Central Philippines: The Impact of Sea Level, Social History, and Tectonism on Archaeological Landscapes

Landscape formation is often discontinuous and punctuated by rapid change, and cultural landscapes may be fragmented and found in chronological and spatial mosaics rather than continuous progressions. Human occupation of the Carcar area of the central Philippines is discussed relative to these effects. Pleistocene evolution of landscapes in Cebu is a complex array of uplifted fossil coral reef platforms that form the lower benches of the central cordillera of the island. These formed during periods of high sea level, and their present altitude has been increased by periodic tectonic uplift. Submarine fossil coral reef platforms are components of this landscape evolution, and at least two at depths of 20 m and 60 m below the present sea level formed in the mid- to late Pleistocene. A submarine flank-margin cave, Marigondon Cave, formed in the 20 m reef platform when subaerial in the period from 80,000–10,000 b.p. More recent Holocene-era sea level change, rising by 1.8 m above present sea level in the period from 2000–6000 b.p. , altered coastal terrain and constrained human settlement to the upper extent of the present coastal plain. Subsequent upland degradation has buried the mid-Holocene shoreline below 2–3 m of colluvial deposits. These two contexts for human settlement are situated in the complex mosaic of the present geography of Cebu, with other localized settlement opportunities such as danao (sinkholes), caves and rock shelters, shorelines, bajadas, and high cordilleran river valleys. The history of physical processes is interleaved with human history, and the choices and cultural changes that themselves impact the landscape.