Fig 1.
a) The Messak is located in the Libyan Central Sahara (Fazzan); b) the Messak is a massif of sandstone that lies between two sand seas, the Awbari to the north, and Murzuq, to the south (source: Google Earth); c) view of the Messak from the south, close to the town of Jarma with excavations of the Garamantes Royal Cemetery by DJ Mattingly and team in the foreground. Sources: Images: Elevation map of Africa from Nasa (http://photojournal.jpl.nasa.gov/catalog/PIA04964), detailed map of Fazzan adapted from Wikimedia Commons (http://commons.wikimedia.org/wiki/File:Libya_Topography.png); photo of Messak by M Mirazon Lahr.
Fig 2.
The Messak is almost entirely without soil or superficial sediments, other than recent Aeolian deposits from the adjacent sand seas (a). The surface is made up of broken rocks (b, c, d), many of which have been humanly modified. In some cases (c), the removal of rocks has led to small depressions that can become small puddles or ponds. Sources: photos by authors.
Fig 3.
Frequency and distribution of lithics on the Messak as recorded in the OXY survey.
a) Satellite image of the Messak, showing the seismic grid lines laid for the oil exploration. Each of these lines was walked by archaeologists from the Libyan Department of Antiquities, in both directions. Major archaeological localities were recorded on and between the lines, and the presence of lithics and rough density recorded in 2 x 2 m box every 100 m along the lines. b) Artefact density across the 2 x 2 boxes from the survey; white circles indicate presences of lithics, with the size reflecting low, medium and high density. c) Detail of a small 3 x 2 km area from within the survey area on the plateau’s surface, showing the presence and density of lithics. Sources: MESSAK SURVEY BACKGROUND MAP: satellite image donated by Occidental Plc. (WGS 1984 UTM Zone 33N, Extent: 2960788.37_291786.562_326263.362_2913482.77)
Table 1.
Numbers of stones and lithics per sample quadrat (1 m2 each).
Fig 4.
Frequency distribution of artefact densities in the 50 1 x 1 m sample squares.