There are some Japanese geologists and archaeologists who still refuse to admit the presence of the Early Palaeolithic in Japan, into which we have been carrying out investigations since 1965. One reason of their denial is that the geological datings of the layers from which lithic implements were obtained are not certain, and another is that the lithic implements themselves are not artificial. In this paper the author intends to certify the opinion that there was the Early Palaeolithic Period in Japan, by taking up horizons and stone artifacts of the cultural layers ‘0’ of the Iwajuku Site and the cultural layers 5-8 of the Hoshino Site. The author published a paper entitled “Problems of the Early Palaeolithic in Japan” in this Journal, Vol. 9, No. 3·4, 1971, and the present paper deals with the discussions supplementing the previous paper.
The so-called pebble tools from western Japan were assigned to the early palaeolithic age by some archaeologists. However, similar implements have also been found from the Jomon age. In general, they are classified into three categories, the chopping tool, hand-axe and chopper, of which the first two are rather widely distributed. The fact that these tools were often found associated with such flake tools as knives and points, suggests that they are of the late palaeolithic age. The older limit of age of these pebble tools may go back to 35600 years B. P., and similar tool-making techniques may have continued into the Jomon age.
A. The Nogawa Site and its Stone Culture (KOBAYASHI and ODA) 1. The Nogawa site is located in Kamiishihara, Chofu City, Tokyo. It sits on a low bluff on the Tachikawa Terrace facing across a stream toward the higher Musashino Terrace marked by the Kokubunji Cliff Line (fig. 1). 2. The site was first excavated in 1964, and exploratory excavations were carried on for the next several years (Kidder et al.: 1970). Then a project to widen the stream threatened to destroy the site, and in response the Nogawa Site Excavation Group was formed to excavate the endangered part of the site. Excavations were carried out from June to the end of August 1970 (Nogawa Iseki Chosa Kai: 1970, 1971a, 1971b, 1971c). 3. Geologically the site has thirteen strata (fig. 3). The base stratum XIII is gravel. Over this are nine layers of loam, strata IV to XII, the so-called Tachikawa loam. Four of these strata, strata IVb, V, VII and IX, are black bands of fossil soils. Stratum III is the soft loam, stratum II is a brown humus, and stratum I is a black humus. 4. Culturally there are eleven layers, ten Preceramic Period layers (numbered III, IV1, IV2, IV3a, IV3b, IV4, V, VI, VII and VIII to correspond to the geological strata in which they were found) and one mixed Jomon Period layer in stratum II. More than 10, 000 artifacts were recovered from the Preceramic Period layers. Over 2, 000 are tools or flakes. Another more than 7, 000 artifacts are fire-reddened gravel usually found in heaps. The clarity of stratification, the number of layers, and the quantity of artifacts make Nogawa the best stratified, Preceramic Period site in Japan. 5. The Nogawa data, when correlated with data from other sites in Kanto (fig. 7-10) (in particular, the Heidaizaka Site and ICU Location 15 in Koganei City and the Tsukimino Site Group on the Sagami Terrace in Kanagawa Prefecture), allows definition of four broadly defined phases for the Preceramic Period. The earliest phase, Nogawa layers VIII to V (Heidaizaka layers X to V), has mostly flake tools plus some heavy-duty tools made from pebbles. Phase II, Nogawa layers IV4 to IV1, is characterized by backed blades. Temporally related changes in the form of these backed blade tools are apparent. The early assemblages of the phase are marked by lightly worked blades of knife-like form. Later assemblages see changes to smaller tools of more geometric form and the appearance of small, bifacially worked points. (Phase III of the South Kanto Preceramic Period is distinguished by the presence of microblades and the cores from which they were obtained. However, this phase is not represented at the Nogawa site). The latest Preceramic Period phase, phase IV, Nogawa layer III, consists mainly in large, biface points and pebble tools. 6. The heaps of fire-reddened gravel are found mostly in Nogawa layers IV1 to IV4, i. e. Preceramic Period phase II. X-ray diffraction analysis done by M. Suzuki of Tokyo University shows the stones to have been heated to more than 600°C. The meaning of these heaps is unclear. It is not known whether they were used as found-single layers of gravel spread in near circular patterns one to two meters in diameter-or whether they were simply disposed of at a location in the site some distance from where they were used. However, many of the stones do have a kind of tar-like substance on them, and one is probably justified in thinking the stones were used directly in some manner for cooking. Also, pounding stones, grinding stones and anvil-like stones are frequently found in close proximity to the heaps.
In the description of the chronology of the Paleolithic cultures from various localities of Japan, as well as of the world, the famous glacial succession in the Alpine Forelands is commonly taken as the standard. After reviewing the chronology and correlation in the standard areas of the Pleistocene subdivisions in Europe, a proposal is made to avoid confusion in the international correlation of the Middle and Late Pleistocene including the ages of the Paleolithic cultures arising from the application of the Alpine climate units to those outside the Alpine Forelands. It is suggested that the usage of European stage names be avoided and that domestic places be proposed on objective facts. The stratigraphic horizon of the oldest cultures reported from the northern part of the Kanto Region and other localities of Japan corresponds to the incipient phase of the last and most significant lowering of sea-level in the Late Pleistocene, which is well recognized throughout the coastal region of the Japanese Islands and adjacent areas.
South Kanto has offered the standard strata for studying the chronology of the late Quaternary in Japan. Recent years, many preceramic sites have been excavated, among which the Nogawa site and the Tsukimino sites were most intensively researched because of their abundant bearing of stone implements and of their clear stratigraphical backgrounds. The information obtained from these sites has gradually made clear the typological sequences in preceramic history in South Kanto. In the present study, three methods of chronology which are independent in regard to their disciplines, that is, tephrochronology, radiocarbon dating and obsidian dating, have been applied to the stratigraphic comparison of the Tachikawa Loam both in the Sagamino terrace and in the Musashino terrace. Results obtained from the three methods mentioned above coincide with each other within the existing errors, and give the basis for the future study as shown in Fig. 7.
Since the first finding of the famous Iwajuku site, many Preceramic remains have been collected from various places in North Kanto districts, Japan. All these remains are discovered in the “Kanto Loam” which consists mainly of Late Pleistocene tephra layers, and their stratigraphical positions are mostly well documental. Today, as the result of archaeological and geological researches, most of these remains are considered to be the Late-Palaeolithic. This paper deals with some stratigraphical descriptions and discussions on the so-called Early Palaeolithic layers which some archaeologists (Serizawa: 1970 etc.) have recently reported to have found in the lower part of the Kanto Loam at Hoshino, Iwajuku and other sites in the North Kanto. The tephro-stratigraphic positions of the layers at there Preceramic sites are shown in Fig. 9 in the text. Stratigraphically is out of question, that the so-called artifacts were discovered from the deposits evidently below the Hassaki pumice bed (HP, 40, 500±3, 500 years B.P.). According to Serizawa's definition that the culture prior to 30, 000 years B.P. in the Early Palaeolithic, the so-called artifacts belong to the Early Palaeolithic. It is very doubtful, however, whether the specimens which those archaeologists believe to be the Early Palaeolithic are actually artifacts or not. They may rather be regarded as mere clastic breccias which were formed by natural agencies in relation to talus, earthflow or volcanic mudflow depositions. Therefore, it is very precarious to assume that these specimens are the Early Palaeolithic artifacts without taking into goodaccount of the complicated geological and geomorphological factors at each site.