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TABLE 1. Explanations of outcrop and sample. For detailed sampling locality, see Figure 2.

OutcropExplanationSampleLithology and sampling position





OU1 Located in north of Shimajiri settlement northernmost of Miyakojima; lower three meters, alternations of decimeter order gray sandy siltstone and fine sandstone beds; upper three meter, massive siltstone. 18 Silty sandstone; taken from uppermost of lower alternation member.
OG1 Located in cliff at about 1.2km northwest of Pisseoganzaki cape; about 10m high; composed of well-sorted very fine sandstone or sandy siltstone, contains bivalve shell fossils. 11 Siltstone; taken from lower part of the outcrop.
OG2 Located in about 800m southwest of Pisseoganzaki cape; a small outcrop of about 1m high on ground floor of residental development land; gray clayey siltstone overlain by poorly sorted sandstone bed containing rip-up clasts; sand-pipes, 1cm in diameter, penetrating into the lower siltstone bed from the base of upper sandstone bed. 3 Mixture of sandstone and siltstone; taken from lower siltstone bed of exposure but contains sand-pipes extending from upper sandstone bed.
3-2-low-silt Siltstone; taken from the lower bed.
3-2-up-sand Fine sandstone; taken from upper sandstone bed.
OG3 Located about 200m southwest of Locality OG2; composed mainly of massive siltstone and occasionally contains very fine to medium sandstone. 10 Siltstone; taken from a massive siltstone part.
YH1 Located in about 200m east of shrimp farm south of Takano fishing port; approximately 5m high and 5m wide; composed of massive and gray siltstone. 17 Siltstone; taken from middle of the outcrop.
YH4 Located in the western part of Yonahamazaki (cape); approximately 5m high; massive siltstone-clayey siltstone facies. 6 Both samples 6 and 6-2, siltstone; taken from lowermost of the exposure, almost the same horizon.
YH3 Located about 1400m west of Yonahamazaki; about 2m high; massive siltstone facies. 16 Siltstone; taken from upper part of the exposure.
YH2 Located close to the YH3; 4m high; consists of massive siltstone with intercalations of thin tuff beds, 5-10cm rhick. 15 Siltstone; taken from approximately 1m high from the base of exposure.
YH5 Located about 700m southeast of Yonahamazaki; about 15m high; massive siltstone facies, molluscan fossils rare. 7 Siltstone; taken from basal part of the exposure.
YH6 Coastal cliff, located 2300m southeast of Yonahamazaki; 3m high and 3m wide ; massive siltstone facies. 14 Both samples 14 and 14-2, siltstone; taken from the basal part of the exposure.
YH7 Coastal cliff, 200m south of the YH6; 5-6m high and 10m wide; consists mostly of massive siltstone and intercalates several thin (2-3cm) fine acidic tuff layers and sandy siltstone beds. 8 Sandy siltstone; taken from 3m high from base of the exposure.
8-2 Siltstone; taken from about 20cm higher horizon of sample 8.
YH8 Located near Sugama village, southwestern part of Miyakojima; about 1m high; composed of massive siltstone; probably correlatable to the lower part of the Yonahama formation in northeast coast section. MK01 Siltstone; taken from the base of exposure.
MB1 Located about 1km south of the YH7, 500m inland from the Urasoko beach: about 20m high; rhysmic alternations of fine sandstone and siltstone, sanstone beds 2-5cm thick and siltstone beds 10-20cm; only one outcrop of Minebari Formation in east coast of Miyakojima in this study. 9 Siltstone; no molluscan fossil.
MB4 Located in south coast of the island, south of Bora settlement (also MB2~8); about 1m high; massive clayey siltstone rich in trace fossils; molluscan fossil not found. 5, 5-2 Both samples 5 and 5-2, siltstone; taken from almost the same horizon, middle of the exposure.
MB5 Located about 10m above the MB4; 4m high and 18m width; bedded alternation of sandy siltstone intercalating thin fine sandstone. 2 Taken from sandy siltstone bed of alternation; diverse molluscan fossils included.
2-2 Taken about 1m below the sample 2, close to the bottom of exposure; lithology is the same as sample 2.
MB6 Located about 7m above the MB5; almost massive facies intercalating thin sandstone beds; This outcrop and following MB7 and MB8 expose almost continuously. 1, 1-2 Both samples 1 and 1-2, sandy siltstone; taken from almost the same horizon of massive sandy siltstone facies.
MB7 Located about 50cm above the MB6; siltstones intercalating thin sandstone beds. 12 siltstone just above thin sandstone bed rich in fossil foraminifers
MB8 Located above MB7. 4 Pumiceous massive sandy siltstone; taken about 0.5m above the horizon of Sample 12.
4-2 Pumiceous massive sandy siltstone; about 1m above the Sample 4.
MB3 Basal part of coastal cliff located in west of Bora beach; 1-2m thick below a large floatstone of the Ryukyu Limestone; sandy siltstone and sandstone; a number of sand-pipes in the silty part. MK02A Sandy siltstone including abundant molluscan fossils.
MK02A-2 Sandy siltstone; almost the same horizon of Sample MK02A.
MK02B Siltstone; taken from massive siltstone bed above the mollusca-rich sandstone bed of Sample MK02A.
MB2 Small outcrop of fine silty sandstone contaning abundat rip-up clasts of siltstone in chatic texture, about 2m high and 2m wide below limestone block; significant bioturbation, including bivalve and fragmental simple coral fossils. 13 Taken from a sandy siltstone clast of the exposure.

TABLE 2. List of fossil foraminifera from the Shimajiri Group of Miyakojima (presented in PDF format).


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