Reconnaissance of Paleolithic sites yielding mammalian remains and tephonomy

岩溶地区洞穴沉积物的发掘和勘察我们对冈山县新见的NT洞穴和小森那洞穴的洞穴沉积物进行了发掘。NT洞是一个直径约1米的垂直小洞，洞内充填着含磷的沉积物。我们挖掘到4.5米深，发现沉积物是不分层的泥，含石灰岩角砾岩，其中含有大量哺乳动物遗骸，包括大型野猪（Sus cf.lydekkeri）、大型鹿（Cervus sp.）和较小的鹿（Hydropotes cf.inermis）。该化石组合具有日本所知甚少的中更新世中期动物群的特征，是日本洞穴和裂隙动物群中最古老的一个，从古生物学的观点来看，它是非常重要的。在小森阿南洞，我们进行了地形测绘和试掘。研究和勘测含化石的水沉积物Oru在长崎县益郡芦部的Hatahoko河的河床上进行了实地调查，发现大象的臼齿和骨头碎片产于半固结的砾石层中，新命名为Hatahokogawa组，该层夹在薄火山灰层中。地层中的木材碎片的年代约为40kyr.B.P.by ^<14>C方法。这些骨头碎片散落在河床上，有数百米长。从埋藏学的观点来看，这种发生方式非常有趣。此外，我们在九州、本州和北海道的许多化石地点和考古遗址进行了实地调查或勘察，包括大分县的姬岛、宫崎县的户之郡和静冈县的佐滨。在这些地点和遗址，我们研究了哺乳动物化石（主要是大象）和旧石器时代的文物。

Excavation and reconnaissance of cave sedimets in Karst areasWe excavated the cave sediments of NT Cave and Komori-ana Cave in Niimi, Okayama Prefecture. NT Cave is small vertical cave with a diameter of about 1m, which is filled with fossiliferous sediments. Our excavations to the depth of 4.5m have revealed that the sediments are unstratified mud with limestone breccia which contain a large number of mammalian remains including large wild boar (Sus cf.lydekkeri), larger deer (Cervus sp.) and smaller deer (Hydropotes cf.inermis). This fossil assemblage is very important from paleontological view points, because it possesses the characters of the middle Middle Pleistocene fauna which is poorly known in Japan, and is the oldest among the faunas of caves and fissures in Japan. In Komori-anan Cave, we carried out a topographic mapping and a tentative excavation.Research and reconnaissance of fossil-bearing aqueous sedimentsOru field survey on the riverbed of Hatahoko River in Ashibe, Iki-gun, Nagasaki Prefecture, revealed that molars and bone fragments of elephant occurred from semi-consolidated gravel bed, newly named the Hatahokogawa Formation, which intercalated a thin tephra bed. Wood fragments from the formaiton are dated as about 40kyr.B.P.by ^<14>C method. The bone fragments were scattered on the riverbed with lengths of a few hundred meters. This mode of occurrence is very interesting from taphonomic viewpoints. Additionally, we carried out field survey or reconnaissance at many fossil localities and archaeological sites in Kyushu, Honshu and Hokkaido including Himeshima Island of Oita Prefecture, Tonogori of Miyazaki Prefecture nd Sahama of Shizuoka Prefecture. At these localities and sites, we examined mammalian fossils (mainly elephants) and artifacts of Paleolithic age.