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Gondolin Cave is a fossiliferous dolomitic paleocave system in the Northwest Province, South Africa. The paleocave formed in the Eccles Formation dolomites (Malmani Subgroup, Chuniespoort Group carbonate-BIF Marine Platform). Gondolin is currently the only described hominin-bearing fossil site in the Northwest Province-portion of the designated Cradle of Humankind UNESCO World Heritage Site. The cave is located on privately owned land and is not accessible to the public. As is the case with other South African paleocave systems with Pliocene and/or Pleistocene fossil deposits, the system was mined for lime during the early 20th century. As a result, the system has been heavily disturbed and consists of only a small active cave, a series of ''in situ ''remnant cave deposits, and extensive dumpsites of ''ex situ ''calcified sediments produced during mining activities.〔Watson, 1993; Menter et al., 1999; Adams, 2006; Herries et al., 2006〕 ==Site History and Excavations== No records of the date of lime mining activities at Gondolin, maps or photographs of the cave prior to minining are known to exist. Long-term residents near Gondolin report that the system was mined prior to the 1950s. The cave was named after J.R.R. Tolkien's ''Gondolin'' by the early 1970s.〔 ''Transvaal Museum Bulletin'', Issues 10-22 (1971). The story of the ''Fall of Gondolin'' was published only in 1977, in ''The Silmarillion'', but the name ''Gondolin'' had been published already in ''The Lord of the Rings'' as part of ''Song of Durin's Awakening'' in ''The Fellowship of the Ring'' in the context of the underground city of Moria. 〕 Exposed fossils in the cave system were noted at least as early as the 1970s〔MacKenzie, 1994〕 and brought to the attention of Elisabeth Vrba and David Panagos at the (then) Transvaal Museum (now the Ditsong National Museum of Natural History), who initiated excavations in early 1979.〔Vrba, 1982; Watson, 1993; Adams, 2006〕 The first phase of excavation addressed the extremely fossiliferous ''in situ ''remnant deposits adhering to the northern wall of the cave system (the GD 2 deposits ''sensu''〔Menter et al., 1999; Adams and Conroy, 2005; Adams, 2006〕). The three week 1979 excavation removed approximately 2 cubic meters of calcified sediments from the northern cave wall. While two distinct sediment phases were recognised during the original excavation,〔Vrba, 1982〕 later work with the fossil faunas and geology of the GD 2 deposits did not find any basis for multiple depositional phases within the sampled sequence.〔Herries et al., 2006; Adams, 2006〕 The removed sediment blocks were organised into 43 blocks/trays and processed using acetic acid at the Transvaal Museum. A significant gap in research at Gondolin occurred in the 1980s, during which time all of the excavated blocks were processed (but no further ''in situ ''or ''ex situ ''sampling is known to have occurred). The first description of the result fossil assemblage in 1993 only partially described 4,344 individual specimens that could be assigned to a specific taxonomic levels (out of the 90,663 total specimens recovered from acetic acid processing of the 43 trays/blocks).〔 In 1997 a survey of the sediments at Gondolin included the first sampling of the extensive ''ex situ ''dumpsite deposits at the locality via a test trench (Trench A).〔Menter et al., 1999〕 Materials removed from Trench A included fossiliferous breccia blocks from most, if not all, of the stratigraphic units present at the site (as well as loose fossil specimens sifted from decalcified sediments).〔Menter et al., 1999; Adams, 2006; Herries et al., 2006; Adams et al., 2007〕 From this sampled material (the GD A faunal assemblage), two isolated hominin teeth (representing two different individuals) were recovered. The first, GA 1, is a worn and fractured left molar that has not been confidently attributed to either genus or species (but resembles ''Homo'' in some features.〔 In contrast, GA 2 is a complete left m2 that has been recently analysed and attributed to ''Paranthropus robustus ''(if from a large individual).〔Menter et al., 1999; Grine et al., 2013; Herries and Adams, 2013. Note: Although Menter et al. (1999) and Grine et al., (2013) describe the two hominin teeth as 'GDA-1' and 'GDA-2', neither specimen (or any of the other Trench A fossils) were formally numbered or accessioned prior to cataloging by Adams (2006). Following museum guidelines, the Trench A fossils were given the prefix 'GA' and not 'GDA-'; hence the specimens are more accurately referred to as 'GA 1' and 'GA 2'.〕 The most recent excavations at Gondolin were undertaken in 2003-2004 to explore the largely decalcified GD 1 deposits along the northwestern rim of the Gondolin locality.〔Adams, 2006; Adams et al., 2007〕 A four-week excavation season produced a sample of 4,863 fossil specimens from approximately 50 cubic meters of soil overburden and naturally decalcified sediments that were screened with 1mm mesh. Critically, integration of taphonomic and geologic data from the GD 1 excavations indicated that fundamentally different processes of fossil record formation were occurring at Gondolin during the formation of the GD 1 and GD 2 fossil assemblages. This result highlighted the complex, heterogenous geologic processes that can influence fossil deposition and assemblage composition in South African cave systems during the late Pliocene and early Pleistocene.〔Adams, 2006; Herries et al., 2006; Adams et al., 2007; Adams, 2010〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gondolin Cave」の詳細全文を読む スポンサード リンク
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