大布苏的细石器

本文记述了发现于吉林省西部大布苏泡子东岸二级阶地前缘原生黄土状地层中的486件石制品，其中包括8件石器及100多件细石叶。大布苏地点的细石器材料，类型简单，成型的石器少，分布范围有限，可能是一个临时石器加工点。其时代初步定为旧石器时代末期。

MICROLITHS FROM DABUSU, WESTERN JILING PROVINCE

The Dabusu microlithic site is situated at the foot of the second terrace on the eastern side of Lake Dabusu in Qian'an County, Jiling Province. During the 1985 field season, the author surveyed in the area and discovered and excavated the site. A total of 486 artifacts were recovered from the top layer, 10 cm in thickness. This layer was one in a series of paleosoils from a loess-like deposit over 2 meters deep. The artifacts included 8 retouched tools, 121 microlithic blades, 4 cores, 2 of which are wedge-shaped cores and 2 are semi-conical cores, 1 ground stone and 242 pieces of debris. Of the 121 microlithic blades, only 9 are whole microblades, 36 micro-blades have only the proximal end while 12 have only the distal end, most of the microblades are mid-blade fragments. The average percussion angle is 99.8? The mean average width is 4.5mm. The thickness of 86% microblades is less than 1.5mm. Of the 110 flakes, 5 are modified/edge-damaged pieces. Platform type is recorded for 75 cases. The flakes of plain platform are the largest class (45%), while crested (15%) and linear (12%) platforms account for 27%. The remainder are cortex (8%), prepared (6.7%) platforms and others such as trimmed and scarred platforms. Flakes with plain platforms tend to be the blanks of shaped-tools and a kind of successful striking flakes because of its regular shape and its size similar to that of the shaped-tools. The characteristics of the Dabusu industry are as follows: 1. The raw material of the artifacts is mainly flint. 2. Microcores were carefully prepared, especially on their platforms. The principal flaking method is indirect percussion, the second most common technique is direct percussion and the bipolar technique was used only sporadically. The microlithic blades are very fine, thin, and plain on the ventral surface as well as regular in shape. Therefore, it is believed that the pressure flaking technique for these microlithic blades is quite advanced. All the microcores are singleplatform cores. 3. No polished tools have been found at the site in spite of a possible ground stone rock. No choppers, points and "whole bodyretouched blade" which are most common in microlithic sites in Northern China have been found, too. 4. All tools were made on flakes, retouch on the tools occurs mostly from the ventral to the dorsal surfaces on the right side of the flakes. Only one was bifacially retouched. Direct percussion method was used commonly to retouch but the pressure method might also have been used. 5. The artifacts are very small in size, the largest dimension being less than 40mm, with the exception of the ground stone. Only one species of mammalian fossil (Microius brami) which is of little dating significance, was found from the site. In addition, there are not enough materials for dating, so the absolute age of the site cannot be determined. According to the geology and stratigraphy, it is considered that the age of Dabusu Site is from the latest Pleistocene to the earliest Holocene, and the abosolute age is about 10,000 years or a little later.