The 1st excavation of the Sorori Locality A, Peat II Pit has concluded that two peat soil layers were found as the Top and the Bottom Peat layers. According to the 2nd close examination, however, it was identified that the area has contained three peat layers: the Upper Peat newly identified, the Middle Peat which has been identified as the Top according to the 1st examination, and the Lower Peat which has been identified as the Bottom according to the 1st examination.

The Upper Peat was a lenticular shape at 33.0~32.8 meters above sea level and the dates were obtained 9,450BP(GX-28506) and 9,580BP(GX-28505).

Since many grains of rice were unearthed from the Middle Peat(32.13~30.5 meters above the sea level), the layer was excavated as the foremost priority in both examinations. Eight radiocarbon dates were obtained from both Geochron Lab (USA), and six dates from the AMS Lab of Seoul National University (Korea). Totally fourteen dates were gained from 12,500 to 14,620 BP.

Radiocarbon dates were obtained from both Geochron Lab (USA) and the AMS Lab of Seoul National University (Korea) for the Upper Peat (9,500 BP, 2 datings), the Middle Peat (12,500~14,800 BP, 14 datings) and the Lower Peat (16,300 ·17,300 BP, 5 datings). The cross-measurement between the two labs shows the identical values of absolute age. These results achieved confirm that the peat deposits are very stable.

The date 12,500 BP(SNU 01-293) was gained for quasi-rice samples, excavated from the upper part(32.13 meters) of the Middle Peat. This proves that the Peat Layers and the grains of seed rice were from the same age. Besides, “the Sorori type I-1(japonica)” was unearthed from the Middle Peat(31.4 meters) and its date was obtained as 13,920 BP(SNU 01-291).

Before the Sorori rice seed was excavated, the oldest rice in the world was discovered in the caves of Jiangxi, China(10,500 BP) and Huan, China(11,000 BP). As carbonized rice age in the Sorori site is the world’s oldest, it is important for understanding origin, evolution, and spreading of rice species

The 59 carbonized grains were discovered from the Sorori Locality A, Peat II Pit. The 41 grains of quasi-rice and the 18 grains of ancient rice were identified out of them. (Lee, Yung-jo & Woo Jong-yoon, 2002). The ancient rice was classified into the type japonica and indica, and the quasi-rice into the type 1 and 2.

Now, however, the ancient rice shall be renamed as the type Ⅰ and the quasi-rice as the type II. And, the japonica shall be names as the type Ⅰ-1, and the indica as the type Ⅰ-2. The previous quasi-rice type 1 shall be classified as the type Ⅱ-1, and the quasi-rice type 2 as the type Ⅱ-2.

The average length of the type Ⅰ-1 is 7.2 mm and the width is 3.08 mm. The average length of the type Ⅱ-1 is 6.45 mm, and the width 1.7 mm.

Most grains were excavated from the Middle Peat and only one quasi-rice was found from the Lower Peat.


In the 1st excavation, the grains of ancient rice were found from the Top Peat and the grains of quasi-rice were from the Bottom Peat. The in situ was found from the 2nd excavation, because the ancient rice(the type I) and the quasi-rice(the type II) were unearthed together from the Middle Peat.

From the Middle Peat, an amount of plants like weed seeds, grass roots, stems and Insecta were found. Specially Carabidae was newly known as lived in the stem of Gramineae during its larva stage, and construed as related to the excavation of the seed rice.(Chungbuk National University Museum, 2001).

Through the pollen anaysis of Peat samples(Kim, Ju-yong and others, 2002), it was construed that Gramineae has had no problems in surviving. The research of Dr. Yasda Yoshinori shows the same results as well. Thus, it is considered that the existence of the Sorori Rice was definitely possible ecologically.

Several pieces of the same insect fossil were found from the Sorori Peat Soil Layers. This means that the insect has lived very well adopting itself to the surroundings at that time. These kinds of insects have exoskeletons and can be well preserved in the status of the fossil, unless the term is long. Sometimes the identification of the fossil insect can be presumed on the basis of this morphological feature. Through the identification, the life environments of the insect in those days can be discovered by studying the most similar species of present time.

The 26 kinds of insect fossils were found. They were all from Coleoptera, whose exoskeleton is harder than any other insect and who can be preserved for a long time. Coleoptera is, in fact, the largest group of insects around 40 percents of the whole insect class.

The main species were classified into three. The color of the fossil means that before getting dried. But the color changed slightly after the soils have been dried. Maybe it caused by the minute changes in the forms.The identifications are envisioned as;

Insect Fossil 1: Plateumaris sericea, Chrysomelidae, Donaciinae
aeneous variation (Fig. 2 [please check this with the client])
Insect Fossil 2: Carabidae
Insect Fossil 3: Pterostichus, Carabidae, Pterostichinae
Insect Fossil 4: Donacia flemola, Chrysomelidae, Donaciinae or quasi-species
Donacia flemola, Goecke or quasi-species
Insect Fossil 5: Plateumaris sericea, Chrysomelidae, Donaciinae
yellowish green variation

The Plateumaris sericea, Chrysomelidae, Donaciinae of Insect fossil 1, 5 shows the variation in the wing color as aeneous, yellowish green. The species gets found in slough all over the country and also known as one distributed over the East Asian and the Europe. Another unidentified species was reported in Korea, which was classified into the same genus of Plateumaris sericea, Chrysomelidae, Donaciinae. (National Science Museum, 안, pers. comm. [please check this with the client])

The Insect Fossil 4, Donacia flemola, Goecke or quasi, was identified as the same subfamily of Plateumaris sericea, Chrysomelidae, Donaciinae.
It is tinged with black, not very glossy, and has no variation in colors. It gets found over the country and distributed over the East Asia too. These insects out of either Plateumaris or Donacia, Donaciinae were reported that they did harm to those slough plants, specially to the Gramineae or Cyperaceae. Thus, the excavation of an amount of Donaciinae means that the era has been a slough where the Gramineae or Cyperaceae lives a lot.

The Insect Fossil 2 is a kind of Ophionea nigrofasciata(schmidt-Goebel) [Please check with the client on the Ophionea nigrofasciata. Couldn’t find out but Ophionea nigrofasciata.], and tinged with black, has no variation in cloros, and lives mainly on the ground.

And the Insect Fossil 3 was identified as the Pterostichus, Carabidae, Pterostichinae who is mid-sized but the largest one out of the fossil insects. It is also tinged with balck, and not able to fly as the underwings were degenerated. Going on foot, it is known as a predacious insect living on other small insects.

Both 2 and 3 insects are classified in Ophionea nigrofasciata(schmidt-Goebel) according to the shape of their wings. Some species prefer a slough. It means that small insects have lived at the areain the past.

This analysis is showing that the Sorori site where the insects have lived in was a slough before, and the Gramineae or the Cyperaceae has been distributed as well.

DNA analysis shows the early rice sample to be different from the modern intensively farmed varieties(39.6% of the genetic similarity), thereby offering scientists the opportunity to study the evolution of one of the world's principal food sources.

As the results of scanning the remained ear stems of the type Ⅰ-1 and the Ⅰ-2 with the electron microscope, the Sorori rice shows the features of the cultivated rice differentiating from the wild rice. The wild rice does not get cut with ease while the shape is longish and sharp. But the Sorori rice was cut with ease by the external physical force like the cultivated rice. Thus, it is presumed that the Sorori rice was within the stage of the domesticated rice, which is before the cultivated rice.