| JaLCDOI | 10.18926/ESR/49208 |
|---|---|
| Title Alternative | Folded structure of the Carboniferous Ko-yama Limestone Group, Akiyoshi Belt, SW JAPAN |
| FullText URL | esr_019_1_005_011.pdf |
| Author | Inada, Noriyuki| Suzuki, Shigeyuki| Ishida, Keisuke| |
| Abstract | The fold structure of the Akiyoshi Belt was analyzed in Kawakami-cho, Okayama Prefecture, where the Lower Carboniferous to Middle Permian Ko-yama Limestone Group (Yokoyama et al., 1979), Permian Yoshii Group (Sano et al., 1987) and Triassic Nariwa Group (Teraoka, 1959) are distributed. The Nariwa Group unconformably covers the Paleozoic successions (Otoh, 1985). The Lower Carboniferous to Middle Permian Ko-yama Limestone Group, dated by foraminifers and fusulinids (Yokoyama et al., 1979), is mainly composed of massive limestone with basic volcanics, acidic tuff and chert. The Paleozoic successions of the Akiyoshi Belt were folded during the Middle to Late Permian (Suzuki et al., 1990). Strata of the Ko-yama Limestone Group generally strike E-W and dip to the north. The Hoya section about 300 m thick is composed of limestone, basic tuff, chert and acidic tuff, limestone, basic lava and tuff in ascending order. In this section, Ishida et al. (2012) recognized a nearly complete conodont faunal succession ranging from the upper Visean to the lower Moscovian. The faunal succession indicates younging southward, and the strata are overturned. A folded strucuture of tight overfold with north-dipping axial plane was reconstructed. Similar style of small scale overfolds of banded chert and turbidite were observed in the overlying Yoshii Group. |
| Keywords | folded structure Ko-yama Limestone Group Carboniferous Akiyoshi Belt |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2012-12-26 |
| Volume | volume19 |
| Issue | issue1 |
| Start Page | 5 |
| End Page | 11 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2012 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120005232326 |
| JaLCDOI | 10.18926/ESR/49207 |
|---|---|
| Title Alternative | Holocene environmental and sea-level changes of the Okayama Plain – evidence from peat beds – |
| FullText URL | esr_019_1_001_004.pdf |
| Author | Suzuki, Shigeyuki| |
| Abstract | Quaternary peat beds from bore-hole samples deliver information to reconstruct paleoenvironment. Altitudes of dated non-marine peat beds and marine beds allow to be created a sea-level curve. 4 peat beds (A to D) are identified from the uppermost Pleistocene to Holocene deposits of the Okayama Plain. They thought to be deposited at stable events during sea-level change. |
| Keywords | Holocene peat beds paleoenvironment sea-level change Okayama Plain |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2012-12-26 |
| Volume | volume19 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 4 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2012 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120005232325 |
| JaLCDOI | 10.18926/ESR/47747 |
|---|---|
| Title Alternative | Newly proposed landform division in the Kibi Plateau area: Application for a hazard map of landslides |
| FullText URL | esr_018_1_005_010.pdf |
| Author | Suzuki, Shigeyuki| Omizo, Yuna| Hirata, Minoru| Nishigaki, Makoto| |
| Abstract | The Kibi Plateau is characterized by horizontal skylines and they are considered to be an uplifted peneplain. Landform of the plateaus in central part of Okayama Prefecture is divided into "Kibi plateau landform" and "Recent dissecting landform". The Kibi plateau landform is composed of low relief surface and relict mountain. The altitude of the low relief surface varies from 300 to 450m in Kayo area, and 200 to 350m in Kanayama area. The Recent dissecting landform is characterized by escarpment and cuts the Kibi plateau landform. Knick-point is formed at the boundary between two landforms and steep slope is distributed just below the knick-point. The steep slope of the recent dissecting landform is unstable and a potential of landslide is high. |
| Keywords | Kibi Plateau landslide knick-point Okayama Prefecture |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2011-12-26 |
| Volume | volume18 |
| Issue | issue1 |
| Start Page | 5 |
| End Page | 10 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2011 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120003796475 |
| JaLCDOI | 10.18926/ESR/19850 |
|---|---|
| Title Alternative | 岡山県に分布する白亜紀前期羽山層砕屑物質の供給源：砕屑粒の鉱物化学組成とモード組成から導かれる制約 |
| FullText URL | 016_029_042.pdf |
| Author | Asiedu, Daniel K.| Suzuki, Shigeyuki| Shibata, Tsugio| |
| Abstract | Petrographic and phase chemistry studies of detrital grains were carried out on sandstones from the Lower Cretaceous Hayama Formation, Inner Zone of Southwest Japan, to determine their provenance and the tectonic setting during the early Cretaceous. The results of the modal mineralogy suggest that the Hayama Formation has magmatic arc provenance and that deposition of the sediments took place in the back-arc areas with detritus mostly derived from the magmatic arc and rifted continental margins. The chemical compositions of chromian spinel, chlorite and sphene indicate that significant proportions of the detrital grains were derived from mafic and/or ultramafic sources. The source areas are the mafic and ophiolitic rocks in the Sangun-Renge and Akiyoshi terranes and the felsic volcanic rocks probably from either the Akiyoshi terrane or a source not presently exposed in southwest Japan. However, minor amounts of the detritus were derived from the basement rocks; i.e., carbonates and siliciclastic rocks of the Akiyoshi terrane and the metamorphosed mafic rocks of the Chizu terrane. |
| Keywords | modal analysis sandstone mineral chemistry provenance Hayama Formation |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2009-12-25 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 29 |
| End Page | 42 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002309000 |
| JaLCDOI | 10.18926/ESR/19848 |
|---|---|
| Title Alternative | The first Japanese word "chishitsu-gaku" for the "geology" was proposed by Genpo Mitsukuri (1799-1863) |
| FullText URL | 016_001_007.pdf |
| Author | Okada, Hakuyu| Suzuki, Shigeyuki| |
| Abstract | The first Japanese word "chishitsu-gaku" for the "geology" was proposed by Genpo Mitsukuri, a scientific contributor in the Tokugawa regime in the 19th century, who was born in 1799 in Tsuyama in Western Honshu, Japan and had worked for scientific activities of the Tokugawa government from 1839 to 1863. His major works for the first making of the "chishitsu-gaku" for the "geology" have been presented in this paper, also showing his contribution to Japanese sciences. |
| Keywords | Genpo Mitsukuri "chishitsu-gaku" 19th century |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2009-12-25 |
| Volume | volume16 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 7 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002309076 |
| JaLCDOI | 10.18926/ESR/15024 |
|---|---|
| Title Alternative | Microscopic observations of the recent soils: a step for understanding the paleosols |
| FullText URL | 015_009_032.pdf |
| Author | 福地 亮| Suzuki, Shigeyuki| |
| Abstract | The microscopic observations of the recent soil horizons were conducted in Okayama, Japan (moderate climate). The several soil horizons, including two surface (epipedon) and three subsurface horizons, were recognized in the forest, poorly vegetated hill, and riverside around the Okayama University. The umbric epipedon can be segregated from the organic-rich subsurface horizons by the scattered organic materials in thin sections. The ochrich epipedon shows the sandy matrix without any cements and the illuviation of clay minerals. The subsurface horizons identified in the study area are as follows: albic, argillic, and cambic horizons. Each subsurface horizon shows the specific structures in thin sections. The albic horizon is characterized by the absence of the illuviation. The argillic horizon definitely shows the clayey matrix and the illuviation of clay minerals. The primary structures may be retained in the cambic horizon. The microscopic examination of the Miocene paleosols from the Ukan-cho, Okayama, was attempted. By comparing the recent soils, the cambic horizon and spodic horizon, which is characterized by the concentration of sesquioxides, are identified in the paleosols. This attempt suggests that the microscopic observations of the recent soils is a useful guide to understanding the paleosols |
| Keywords | soil paleosol soil horizon soil structure microscopic observation |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2009-03-31 |
| Volume | volume15 |
| Issue | issue1 |
| Start Page | 9 |
| End Page | 32 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002307964 |
| JaLCDOI | 10.18926/ESR/15022 |
|---|---|
| Title Alternative | Permian and Triassic molluscan fossils from the Maizuru Zone,Okayama City, Southwest Japan |
| FullText URL | 015_001_008.pdf |
| Author | Nakazawa, Keiji| Roger Lyman Batten| Suzuki, Shigeyuki| Uwada, Hideto| |
| Abstract | Permian and Triassic molluscan fossils are found from Mitsu-area, Okayama City, Southwest Japan. Permian bivalve and gastropod fossils are collected from mudstones of the Upper Formation of the Maizuru Group. 4 species of bivalves (Nuculopsis? sp. ind., Leptodesma sp. ind., Streblopteria cf. eichwaldi, Posidonia sp. ind.) and 5 species of gastropods (Worthenia cf. corrugata, Callitomaria n. sp. cf. stanislavi, Apachella n. sp. ind., ??Eunemopsis like trochid, ??Yunnania sp.) are identified. Lower Triassic bivalve fossils are collected from sandstones of the Oono Formation. Neoschizodus cf. laevigatus and Bakevellia (Maizuria) kambei are identified. |
| Keywords | Permian Triassic bivalve and gastropod fossils the Maizuru Zone Mitsu area |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2009-03-31 |
| Volume | volume15 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 8 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002307247 |
| JaLCDOI | 10.18926/ESR/13953 |
|---|---|
| FullText URL | ESR_1_9.pdf |
| Author | Suzuki, shigeyuki| |
| Abstract | The Iberian Pyrite Belt is an Upper Paleozoic succession which has been divided into the Phyllite-Quartzite Group, the Volcanic-Sliceous Complex and the Culm Group in ascending order from base to the top. The contacts among them are conformable. These Groups are tightly folded and metamorphosed un-der low-grade conditions during Hercynian times. The first stage folds of the Volcanic-Siliceous Complex and the Culm Group are associate with slaty cleavages (S1), while the Phyllite-Quartzite Group is asso-ciate with schistosities (S1). Fold analysis using cleavages and minoe folds has been utilized in the analysis of the stratigraphy. This led to systematic horizontal collection of specimens (pelitic rocks). S1 texture is defined by paralled alignment of secondary platy minerals which tend to grow larger and together, forming zonal domains toward the Phyllite-Quartzite Group. The clay matrices change to recrystallized quartz toward the Phyllite Quartzite Group. Textural modifications are evidenced by gradational changes from slaty cleavages to schistosities. This shows that recrystallization is the important deformation mecha-nism responsible for S1 development. It also reflects that the deformation was contemporaneous with metamorphism. |
| Keywords | Slaty cleavage Schistosity Recrystallization |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1994-09-20 |
| Volume | volume1 |
| Issue | issue1 |
| Start Page | 9 |
| End Page | 18 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310428 |
| JaLCDOI | 10.18926/ESR/13940 |
|---|---|
| Title Alternative | Application of the remotely operated TV vehicle to make geological maps of the Seto Inland Sea |
| FullText URL | ESR_2_13.pdf |
| Author | Suzuki, Shigeyuki| Inada, Takashi| |
| Abstract | Submarine geological survey using the remotely operated TV vehicle (RV100), was carried out in 4 offshores of the Seto Inland Sea in Kagawa Prefecture. The study areas are west of Kosei Island of Sakaide City, south of Okado-bana of Nankai Town, west of Misaki of Takuma Town and north of Nou-Misaki of Sakaide City. TV vehicle transmite clear pictures of bottom of the sea to the monitor on board. The submarine geology of the study areas are composed of Cretaceous granitic basements and Quaternary sedimentary covers. By using these pictures Recent and Pleistocene deposits could be distinguished and lithology of sediments could also be identified. Lithology of sediments was however difficult to identify using the usual sonic prospecting method. Furthermore, pictures suggesting that ripples are just forming have been obtained. The TV vehicle is convenient in submarine survry, because it can travel much longeer and deeper than human diver. A new method of mapping submarine geology using TV vehicle was developed. |
| Keywords | Submarine geology the Seto Inland Sea remotely operated TV vehicle |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1995-09-20 |
| Volume | volume2 |
| Issue | issue1 |
| Start Page | 13 |
| End Page | 22 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310382 |
| JaLCDOI | 10.18926/ESR/13928 |
|---|---|
| FullText URL | ESR_3_17.pdf |
| Author | Suzuki, Shigeyuki| |
| Abstract | In eastern Chugoku area, Paleogene deposits have not been recognized until fission-track dating of so called "Mountain Gravels" was carried out (Suzuki et al. 1995). Two sedimentation events in Paleogene time (27Ma and 34-35Ma) are inferred by the F-T dating Major lithology of the Paleogene deposits in the study area is graved which is mainly composed of subrounded to rounded cobbles. The "Mountain Gravels" were previously thought to be lower Quaternary deposits. The "Mountain Gravels" is associsted with coal bearing mud, sand, gravel and breccia deposits. The breccia deposits is distributed sporadically between the "Mountain Gravels" and basement rocks. The deposits are mainly composed of poorly sorted breccia and associated granitic sands. It is inferred that the breccia deposits are talus deposits. |
| Keywords | Paleogene breccia talus deposits fission-track dating |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1996-09-20 |
| Volume | volume3 |
| Issue | issue1 |
| Start Page | 17 |
| End Page | 24 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310338 |
| JaLCDOI | 10.18926/ESR/13927 |
|---|---|
| FullText URL | ESR_3_1.pdf |
| Author | Daniel K. Asiedu| Suzuki, Shigeyuki| Shibata, Tsugio| |
| Abstract | Petrographic and geochemical study of sandstones from the Kenseki Formation have shown that the sandstones are compositionally immature. The immaturity is reflected geochemically by their low SiO2 contents (52-66 wt%) and petrographically by low modal percents of quartz and K-feldspar, and high modal percents of plagioclase and volcanic lithic fragmants. The Kensaki sandstones are, however, poor in Na2O (up to 2.1 wt%). Both petrography and geochemistry suggest a heterogeneous source lithologies of acidic and basic volcanics, sedimentary, and ultramafic rocks. Petrographic evidence is supplied by quartz and plagioclase of volcanic origin, acidic volcanic fragments, basic volcanic fragments, volcanic glass, serpentinite fragments and detrital spinel grains. Geochemical evidence is provided by high FeO* (total iron as FeO), MgO, TiO2, CaO and K2O contents. Petrographic and geochemical study of the Kenseki sandstones indicate calc-alkaline oceanic island are provenance. The sediments were locally derived, with Alpine-type ultramafic rocks exposed in the north and volcanic materials of the Akiyoshi Belt supplying the bulk of the detritus. |
| Keywords | Kenseki Formation modal analyses provenance |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1996-09-20 |
| Volume | volume3 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 16 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310277 |
| JaLCDOI | 10.18926/ESR/13916 |
|---|---|
| Title Alternative | Landslide occurrence and geology of the Triassic Nariwa Group, Southwest Japan |
| FullText URL | ESR_4_21.pdf |
| Author | Hotani, Shu| Suzuki, Shigeyuki| Tanaka, Hajime| Yamada, Takuya| |
| Abstract | Geological and topographical study of landslides in the Triassic Nariwa Group has been carried out. Nariwa Group is mostly composed of non-marine deposites and is characterized by cycle of fining upward successions. Landslides abundantly occur in the non-marine successions. Slip surface occure in coaly mudstones that have conspicuously less strength than sandstones. Creeps immediately below slip surfaces contribute to the occurrence of landslides in the Nariwa Group. |
| Keywords | Iandslide Nariwa Group coaly mudstone |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1997-09-20 |
| Volume | volume4 |
| Issue | issue1 |
| Start Page | 21 |
| End Page | 32 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310343 |
| JaLCDOI | 10.18926/ESR/13911 |
|---|---|
| Title Alternative | (14)C ages of Quaternary deposits in Kojima Lake area, Tamano City, Okayama Prefecture |
| FullText URL | ESR_5_13.pdf |
| Author | Sasaki, Hajime| Suzuki, Shigeyuki| |
| Abstract | Two 14C ages are obtained from drilled core samples in Kojima Lake area. One is 7920±250 y.B.P. from peat which is just below silty clay of bay sediments (-14.30-14.61 m) The other is 24900+3450,-2450 y.B.P. from pale milky gray clay of fluvial sediments (-24.15-24.45 m). |
| Keywords | (14)C age Quaternary Kojima Lake area |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1998-09-20 |
| Volume | volume5 |
| Issue | issue1 |
| Start Page | 13 |
| End Page | 16 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 80011114460 |
| JaLCDOI | 10.18926/ESR/13909 |
|---|---|
| Title Alternative | Topography and deposits of terrace of Yokohama Town, Northeast Japan |
| FullText URL | ESR_5_1.pdf |
| Author | Suzuki, Shigeyuki| Miyawaki, Akiko| |
| Abstract | Higher, middle and Lower Terraces (Quaternary) have been distinguished in Yokohama Town, Aomori Prefecture. The Higher Terraces are subdivided into three terraces, H1,H2 and H3. They are distributed in hills. H1 and H2 deposites are composed of gravels of fan deposits. H3 deposits are composed of gravels, sands and mud of alluvial plain deposits. The Middle Terraces are subdivided into three terraces, M1, M1' and M2, and occupy almost all terraces in Yokohama Town. These deposits are composed of beach (sand with gravel) and fan (gravel) deposits. The Lower Terraces are subdivided into two terraces, L1 and L2. The L1 Terrace is distributed in limited area along coast and thought to be composed of beach deposits. The L2 Terrace is distributed in limited area along river and composed of braided stream deposits. |
| Keywords | terrace beach deposits fan deposits Quaternary |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1998-09-20 |
| Volume | volume5 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 12 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310292 |
| JaLCDOI | 10.18926/ESR/13906 |
|---|---|
| Title Alternative | Peat bed of Jomon age in Desaki Beach, Tamano City, Okayama Prefecture |
| FullText URL | ESR_6_23.pdf |
| Author | Suzuki, Shigeyuki| Yukimoto, Koichi| |
| Abstract | Peat bed remains isolated in the shoreline of western beach of Desaki peninsula. Collected samples gave radiocarbon data of 5790±80 and 5810±60 years BP. |
| Keywords | Peat Holocene Desaki Beach |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 1999-09-20 |
| Volume | volume6 |
| Issue | issue1 |
| Start Page | 23 |
| End Page | 28 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310593 |
| JaLCDOI | 10.18926/ESR/13902 |
|---|---|
| FullText URL | ESR_7_47.pdf |
| Author | Yamagiwa Nobuo| Suzuki, Shigeyuki| Okimura Yuji| |
| Abstract | A new rugose coral species, Lithostrotion (Siphonodendron) hinensis is described in this paper. It was collected from the Carboniferous Hina limestone in Okayama Prefecture, Southwest Japan. Judging from the paleontological data, the age indicates probably Late Viaean, Early Carboniferous. |
| Keywords | Early Carboniferous rugosa Lithostrotion (Siphonodendron) Hina Limestone Okayama |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2000-09-20 |
| Volume | volume7 |
| Issue | issue1 |
| Start Page | 47 |
| End Page | 50 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310319 |
| JaLCDOI | 10.18926/ESR/13901 |
|---|---|
| Title Alternative | Tidal notch cut into the Namigata Limestone, 240m above sea level, Ibara City, Okayama Prefecture |
| FullText URL | ESR_7_41.pdf |
| Author | Fujiwara, Takao| Suzuki, Shigeyuki| Maeda, Yasuo| |
| Abstract | The tidal notch and the sea caves which cut into the Namigata Limestone is stiuated in 240m above sea level, Ibara City. The notch assocciates the Namigata Terrace 200m to 240m high. These geomorphological features indicate an event of high sea level. However the age of the event has not been known. |
| Keywords | notch sea cave Namigata Okayama Prefecture |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2000-09-20 |
| Volume | volume7 |
| Issue | issue1 |
| Start Page | 41 |
| End Page | 46 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310395 |
| JaLCDOI | 10.18926/ESR/13900 |
|---|---|
| Title Alternative | Relashonships between "Mountation Gravels" and the Bizen and Tomihara Coal Measures, northern Okayama City, Southwest Japan |
| FullText URL | ESR_7_35.pdf |
| Author | Suzuki, Shigeyuki| Nakazawa, Keiji| Tanaka, Hajime| |
| Abstract | The Bizen and Tomihara Coalfields which were situated in northern Okayama City, had produced lignite during 1940s. Distribution of coal measures indicates that the coal measures are intercalated in the middle of the so-called "Mountain Gravels". The "Mountain Gravels" is subdivided into two formations ; the older, about 34～35Ma, and the younger, about 27Ma, of fission track ages. The older formation inculudes the Bizen Coal Measures. On the other hand, the Tomihara Coal Measures are intercalated in the younger formation. |
| Keywords | Bizen Coal Measures Tomihara Coal Measures Okayama City Paleogene |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2000-09-20 |
| Volume | volume7 |
| Issue | issue1 |
| Start Page | 35 |
| End Page | 40 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310497 |
| JaLCDOI | 10.18926/ESR/13887 |
|---|---|
| Title Alternative | Trace of the Median Tectonic Line in Mima area, eastern Shikoku |
| FullText URL | ESR_8_1_13.pdf |
| Author | Mizui, Yoshinobu| Tachibana, Toru| Suzuki, shigeyuki| |
| Abstract | Tracing outcrops of shear zone were used to describe the geometry and structure of the Median Tectonic Line in Mima area, eastrn Shikoku. A distinct new fault outcrop was discovered between the Mino and Ikuchi Faults at the northern slope of the Mt. Boso. These two faults are regarded as a single continuous fault. The analysis of surface fabrics of quartz in fault in fault gauge has been carried out to determine relative fault activity events. |
| Keywords | surface fabrics fault gauge Mino-Ikuchi Fault Median Tectonic Line |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2001-09-20 |
| Volume | volume8 |
| Issue | issue1 |
| Start Page | 13 |
| End Page | 28 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310656 |
| JaLCDOI | 10.18926/ESR/13885 |
|---|---|
| Title Alternative | Miocene Ukan Formation, Ukan Area, Okayama Prefecture, Southwest Japan |
| FullText URL | ESR_8_1_1.pdf |
| Author | Fujiwara, Takao| Taguchi, Eiji| Suzuki, shigeyuki| |
| Abstract | In this paper, we deal with the Miocene Ukan Formation, sporadically distributed in Ukan-cho, Okayama prefecture, from a viewpoint of analysis of lithology and molluscan assemblages. The Ukan Formation is lithostratigraphically divided into the Suzuoka Conglomerate, Yamagata Muddy Sandstone, Shimoyokomi Sandstone and Conglomerate, Azechi Sandstone and Conglomerate, Tsuneyama Siltstone Members in ascending order. The following 6 molluscan assemblages are recognized. The lower four members and the last member is correlative to the Lower Sandstone and Upper Shale Formation of the Bihoku Group, respectively judging from lithology and fauna. The temporal chages of the above mentioned molluscan assemblages represents that gradual deeping of sea during the depositional period from the Suzuoka Conglomerate and Yamagata Muddy Sandstone Members to the Azechi Sandstone and Conglomerate Member via the Shimoyokomi Sandstone and Conglomerate Member, and abrupt deeping of sea seems to have happened between the Azechi Sandstone and Conglomerate Member and the Tsuneyame Siltstone Member. |
| Keywords | Lithology Molluscan assemblage Paleoenvironmental change Ukan Miocene |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2001-09-20 |
| Volume | volume8 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 12 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | 岡山大学地球科学研究報告編集委員会 |
| File Version | publisher |
| NAID | 120002310604 |
