Apr. 2025, Best Paper Award 2025, Yamaguchi, N., Ando, T., Enokida, H., Nakada, N., Yamaki, S. and Ohta, T. 2024, Logratio analysis of components separated from grain-size distributions and implications for sedimentary processes: An example of bottom surface sediments in a shallow lake. Sedimentology, 71, 1291–1304., The Sedimentological Society of Japan
山口直文;安藤 毅;榎木田浩孝;中田夏海;八巻翔太;太田 亨

Mar. 2018, 最優秀ポスター賞, 津波による海底砂の運搬プロセスに関する実験的研究, 日本堆積学会
鈴木貴大・篠崎鉄哉・山口直文・関口智寛
Japan society

Sep. 2016, 優秀ポスター賞, 日本地質学会
Kazuki Haneta;Kazumi Ito;Toru Tamura;Naofumi Yamaguchi
Japan society

Sep. 2010, 地質学会表彰, 地球科学系の若手研究者の継続的育成活動, 日本地質学会
地球システム・地球進化ニューイヤースクール(NYS)事務局

Sep. 2007, 優秀講演賞, 日本地質学会
山口直文・関口智寛・関口秀雄

Mar. 2006, 最優秀ポスター賞, 日本堆積学会
山口直文 ・関口智寛・増田富士雄

Sep. 2004, 優秀講演賞, 日本地質学会
山口直文 ・増田富士雄

Threshold for oscillatory-flow ripple initiation on cohesive and non-cohesive mixtures of sand and mud
Naofumi Yamaguchi; Yuko Matsuhisa; Tomohiro Sekiguchi; Xuxu Wu; Robert M. Dorrell, Lead
Coastal Engineering Journal, Dec. 2024, [Reviewed]

Fragmentation and separation of diatom valves in modern shallow lake sediments: a case study in Lake Kitaura, Japan
Kento Kumisaka; Naofumi Yamaguchi; Yusuke Okazaki, Springer Science and Business Media LLC
Journal of Paleolimnology, 01 Jul. 2024, [Reviewed]

Logratio analysis of components separated from grain-size distributions and implications for sedimentary processes: An example of bottom surface sediments in a shallow lake
Naofumi Yamaguchi; Tsuyoshi Ando; Hirotaka Enokida; Natsumi Nakada; Syota Yamaki; Tohru Ohta, Lead, Wiley
Sedimentology, 16 Jan. 2024, [Reviewed]

Validation of appropriate estimation criteria for the number of components for separating a polymodal grain-size distribution into lognormal distributions
Naofumi Yamaguchi, Lead, Springer Nature
Progress in Earth and Planetary Science, 13 Dec. 2023, [Reviewed]

Effect of sediment supply on geometry of wave ripples: preliminary results of flume experiment　　　　　　　　　　　　　　　
Naofumi Yamaguchi; Toshifumi Taki and Tomohiro Sekiguchi, Lead, 日本堆積学会
Journal of the Sedimentological Society of Japan, 28 Feb. 2022, [Reviewed]

東京湾の砂質干潟において外来性二枚貝ホンビノスガイMercenaria mercenariaの生物攪拌が底質およびベントス群集に与える影響
土屋 渚・青木 茂・植松 幸希・鳥羽 光晴・山口 直文・岡本 研, 日本水産学会
日本水産学会誌, Jan. 2021, [Reviewed]

Flume experiments test grain-size distribution of onshore tsunami deposits
Tetsuya Shinozaki; Naofumi Yamaguchi; Tomohiro Sekiguchi, Elsevier
Sedimentary Geology, Aug. 2020, [Reviewed]

The white cliffs of the Upper Cretaceous Chalk Formations at Flamborough Head, north-east England
Satoshi Tonai; Tomoyuki Sato and Naofumi Yamaguchi
Journal of the Geological Society of Japan, 15 May 2019, [Reviewed]

Current progress and future perspectives of the research on tsunami deposits using flume experiments
Naofumi Yamaguchi
The Journal of the Geological Society of Japan, Feb. 2019, [Reviewed]

Roundness of ripple crest and its implication for sedimentary process
Naofumi Yamaguchi
Journal of the Sedimentary Society of Japan, Feb. 2019, [Reviewed]

Sedimentary processes and the distribution of tsunami deposits on a narrow coastal lowland backed by a cliff in flume experiments
Yamaguchi; N. and Sekiguchi; T., Lead
Journal of Sedimentary Research, 03 Apr. 2018, [Reviewed]

Late Holocene aeolian sedimentation in the Tottori coastal dune field, Japan Sea, affected by the East Asian winter monsoon
Toru Tamura; Yoshinori Kodama; Mark D. Bateman; Yu Saitoh; Naofumi Yamaguchi; Dan Matsumoto, Many dune fields that have formed along the southern coast of the Japan Sea are influenced by the north-westerly winter monsoon, which transports beach sand landwards. The Tottori coastal dune field of the Japan Sea has not been disturbed much by human activities until the 20th century and thus is expected to provide a continuous record of the relationships between the winter monsoon and aeolian sedimentation. We examined new ground-penetrating radar profiles and optically stimulated luminescence (OSL) ages of quartz sand from transverse dune ridges in the western part of the dune field in addition to existing data in the eastern part. This allowed us to extend the study period to cover the past 1000 years and to effectively compare the sedimentary record with other coastal dune fields in East Asia and other palaeoenvironmental proxies. OSL ages from older dune sediments suggest considerable aeolian activity from the 10th to 12th century AD, whereas a hiatus of dune sediment record between the 12th and 15th centuries was detected. These results suggest that during the Medieval period aeolian activity was low or that extensive erosion removed most of the deposits. Since the late 15th century, dune sedimentation has apparently been broadly continuous, though with periods of higher and lower activity. In both of the eastern and western parts, most of the dune ridges accreted landwards, but clear seaward accretion occurred during the 18th century, possibly reflecting a decrease in wind strength that restricted sand transport. In contrast, two significant landward accretion events are inferred to have occurred from the late 15th to 17th centuries and around 1840, corresponding to periods of increased dust fall in China, which suggests an enhanced winter monsoon, and to cold periods suggested by the decline of the sunspot number. The timing of periods of inactive and active dune sedimentation, inferred from alternations of organic soil and aeolian sand, in other coastal dune fields of East Asia appears to be concordant with corresponding periods in the Tottori dune field. We thus propose that other Japan Sea dune fields may also provide a valuable record of East Asian winter monsoon fluctuations. (C) 2015 Elsevier Ltd and INQUA. All rights reserved., PERGAMON-ELSEVIER SCIENCE LTD
QUATERNARY INTERNATIONAL, Mar. 2016, [Reviewed]

Effects of tsunami magnitude and terrestrial topography on sedimentary processes and distribution of tsunami deposits in flume experiments
Naofumi Yamaguchi; Tomohiro Sekiguchi, Lead
Sedimentary Geology, 04 Sep. 2015, [Reviewed]

Quantitative estimation of erosion rate based on temporal change of rock coasts composed of volcanic deposit
Shimpei Uesawa and Naofumi Yamaguchi, The quantitative deduction of the evolutionary history of rocky coasts is difficult because rocky coasts form mainly by erosional processes that evolve at a rate that is generally very slow, without preservation of geological evidence that would indicate how this evolution occurred. In the case of coasts composed of volcanic ejecta, however, erosion rates can be investigated via previously recorded eruption ages and landform changes. This note presents an outline of previous studies that have attempted to estimate coastal erosion rates based on volcanic deposits., The Geological Society of Japan
Journal of the Geological Society of Japan, 15 Aug. 2014, [Reviewed]

Ripples under partially standing waves for different reflection coefficients: a laboratory experiment
Naofumi Yamaguchi and Tomohiro Sekiguchi, Lead, 日本堆積学会
Journal of the Sedimentological Society of Japan, 20 Dec. 2013, [Reviewed]

Large bedform generated by the 2011 Tohoku-oki tsunami at Kesennuma Bay, Japan
Tsuyoshi Haraguchi; Kazuhisa Goto; Masataka Sato; Yuichi Yoshinaga; Naofumi Yamaguchi; Tomoyuki Takahashi, The 11 March 2011 MW 9.0 Tohoku megathrust earthquake off the Pacific coast of Japan was a salient event in the history of Japan. The resultant huge tsunami (the 2011 Tohoku-oki tsunami) inundated a vast coastal area of northeastern Japan, causing widespread devastation. Twenty days after the tsunami, we analyzed the impact of the tsunami on the sea bottom of the Kesennuma inner bay using side-scan sonar to explore the damage and bathymetric change in the harbor. Herein we present the first direct evidence that the sea bottom sediments of around 10-15m were largely reworked by the tsunami to thickness of a few meters, and that large dunes were formed by the tsunami. Considering that the sea wave influence is as weak as it is inside the inner bay, the potential exists that even meter-thick paleo-tsunami deposits are preserved in shallow sea bottoms with large bedforms. This finding will be a stepping-stone to future geological studies of tsunami effects in shallow sea regions. © 2012 Elsevier B.V.
Marine Geology, 01 Jan. 2013, [Reviewed]

Relationship between advective pore-water exchange at sediment-water interface and wave ripples
Naofumi Yamaguchi, The Sedimentological Society of Japan
Journal of the Sedimentological Society of Japan, Aug. 2012, [Reviewed]

Building of shore-oblique transverse dune ridges revealed by ground-penetrating radar and optical dating over the last 500 years on Tottori coast, Japan Sea
Toru Tamura; Mark D. Bateman; Yoshinori Kodama; Yu Saitoh; Kazuaki Watanabe; Naofumi Yamaguchi; Dan Matsumoto, Coastal dunes provide valuable information on the past aeolian activity. Better characterization of internal dune structures and their chronology potentially can greatly improve the interpretation of past environmental changes. Ground-penetrating radar (GPR) and optically-stimulated luminescence (OSL) dating was applied to two transverse dune ridges which are arranged obliquely to the shoreline on the Tottori coast, Japan Sea. Data shows that the inner ridge has a core of Pleistocene dune draped with Holocene sand, while the outer ridge consists only of Holocene sand. The Holocene dune is generally dominated by landward migration, but the outer ridge shows a clear seaward accretion during the 18th century AD. OSL dating showed concordant results with radar stratigraphy and topographic changes since AD 1932 revealed by maps. From this we were able to present the first detailed report of the multi-decadal- to centennial-scale dune formation for the last 500 years in East Asia. contemporaneous with the Little Ice Age, during which many European coastal and inland dunes were activated. In East Asia, it is thought that the winter monsoon plays an important role for aeolian processes. The seaward migration during the 18th century reflects a decrease in wind capacity, which restricted sand transport nearshore, being related to decline in winter monsoon revealed by Chinese historical documents. In contrast, two remarkable events of landward accretion occurred in AD 1580-1640 and around AD 1840, respectively, corresponding to periods of increased dust fall in China, which suggest enhanced winter monsoon. The zone of maximum sedimentation shifted through time from the inner to outer ridges, and also towards the seaward end of the shore-oblique dune ridge, reflecting an expansion of the dune field caused by shoreline progradation. These suggest that the effective combination of GPR and OSL dating was critical in detailed characterization of the complicated depositional pattern of the transverse dune ridge, and thus in reconstruction of the past aeolian activity. (C) 2011 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
GEOMORPHOLOGY, Sep. 2011, [Reviewed]

Variability of wave-induced ripple migration in wave-flume experiments and its implications for sediment transport
Yamaguchi, N.; Sekiguchi, H., Lead
Coastal Engineering, Jun. 2011, [Reviewed]

Basal slip plane of Kurotaki unconformity in the Boranohana area along the Pacific coast of the Boso Peninsula, Central Japan
Otsubo; M.; Yamaguchi; N.; Nomura; S.; Kimura; N.; and Naruse; H.
Island Arc, May 2011, [Reviewed]

Two patterns of three-dimensional grain fabrics corresponding to depositional processes in experimental microdelta deposits using rice grains
Naofumi Yamaguchi and Fujio Masuda, Lead, In this study, rice grains were used as the bed material in flume experiments conducted to analyze three-dimensional grain fabrics in microdelta deposits, developed under three sets of hydraulic conditions. Rice grains are nearly uniform ellipsoids, making it possible to interpret not only patterns of imbrication, but also the orientations of individual grains based on the apparent lengths of their long axes projected onto a vertical section parallel to the current direction. Two predominant fabrics were observed at the center of experimental microdelta deposits: (1) grains oriented parallel to the current direction with an imbrication angle close to the foreset dip angle, and (2) grains with random orientations and horizontal imbrication. The first type of fabric appears in grains that have first settled on the uppermost lee slope and have subsequently been relocated and reoriented by discontinuous grain flows (avalanches). The second type of fabric appears in grains that have dropped over the full length of the lee slope and have not been relocated or reoriented by later grain-flow events. The results of this study suggest that the characteristics of three-dimensional grain fabrics may contribute toward an understanding of the depositional conditions of deposits formed by slip-face progression., The Geological Society of Japan
Journal of the Geological Society of Japan, Mar. 2011, [Reviewed]

Coastal barrier dune construction during sea-level highstands in MIS 3 and 5a on Tottori coast-line, Japan
Tamura, T.; Kodama, Y.; Bateman, M.D.; Saitoh, Y.; Watanabe, K.; Matsumoto, D.; Yamaguchi, N.
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011, [Reviewed]

鳥取砂丘の地中レーダ断面
田村 亨; 小玉芳敬; 齋藤 有; 渡辺和明; 山口直文; 松本 弾, 日本第四紀学会
第四紀研究, Dec. 2010, [Reviewed]

砂浜－砂丘系における漂砂環境の連関を読み解く試み
東良慶; 関口秀雄; 山口直文, The sediment routing process in natural beach-dune systems plays an important role for sustaining the topography of sandy beach. Recent practices of coastal protection, however, tend to suppress sediment transfer between a coastal dune and the fronting sandy beach, reducing resilience of the beach subject to severe wave forcing. This study explores linkage between the beach and dune processes. The resistivity explorations and surface-wave prospecting performed on the coastal dune identified the sedimentary architecture of it, in conjunction with examination of existing borehole logs. Notably, there occurs a buried deposit of old sandy dune below the current beach surface. Furthermore, the examination of ten vibrocores retrieved from the seabed suggests that the deposit of well consolidated old dune extends out to the sea., Japan Society of Civil Engineers
土木学会論文集B2（海岸工学）, Nov. 2010, [Reviewed]

EFFECTS OF SETTLING AND PREFERENTIAL DEPOSITION OF SEDIMENT ON RIPPLE ROUNDNESS UNDER SHOALING WAVES
Naofumi Yamaguchi; Hideo Sekiguchi, Lead, A comprehensive series of wave-flume experiments were performed to examine the effects of settling of entrained sediment on ripple roundness, using three sizes of well-sorted quartz sand (D(50) = 0.32, 0.49, 0.73 mm). The observed ripple profiles were closely examined with reference to ripple roundness and ripple asymmetry. In order to quantify the effect of sediment settling, settling time factor ohm(s) ((= n/(w(0)T); n is ripple height, w(0) is settling velocity, and T is wave period) is newly introduced. It is shown that ripples developed under shoaling waves manifest the following geometrical features pertaining to ripples. (1) The measured performance of ripple roundness correlates systematically with ohm(s), irrespective of grain size. (2) The preferential deposition of entrained sediment on the ripple crest and the onshore-side slope of each ripple is accentuated under conditions of smaller ohm(s). Such deposition takes place under shoaling waves when the oscillatory flow direction is reversed from onshore to offshore, thereby allowing the entrained sediment to stall, to some extent, prior to being subjected to the subsequent peak offshore-going flow. Thus round-crested ripples ensue. (3) The way in which preferential deposition occurs under shoaling waves, is similar to the deposition process that occurs under combined flows on rippled beds (Yokokawa et al. 1995). (4) This reasoning led to a comparison of the ripple roundness and ripple symmetry in both flow regimes. Ripples formed under shoaling waves are in cases significantly round-crested with marked asymmetry. In contrast, equally round-crested ripples under combined flows (Yokokawa 1995) are commonly more symmetrical in profile. Thus, combined-flow ripples can be identified from the geological record using their degree of roundness and symmetry of their profile., SEPM-SOC SEDIMENTARY GEOLOGY
JOURNAL OF SEDIMENTARY RESEARCH, Sep. 2010, [Reviewed]

Effect of velocity hiatuses in oscillatory flow on migration and geometry of ripples: wave-flume experiments
Naofumi Yamaguchi; Hideo Sekiguchi, Lead, A series of wave-flume experiments was conducted to closely look at characteristics of geometry and migration of wave-generated ripples, with particular reference to the effect of velocity 'hiatuses' during which the near-bed flow velocity becomes much smaller than the threshold of sediment movement. Three types of wave patterns were generated: two types for simulating waves with intervening velocity hiatuses; and regular waves for comparison purposes. In the former two types, two different wavelengths of water waves were generated alternately in the course of a wave test: the wave with a longer wavelength was set large enough to mobilize the bottom sediment, whereas the wave with a shorter wavelength was set too small to mobilize the sediment. The former two types were designed to be different in sequence of convexity and concavity of wave patterns. The sequence with the convex-concave longer wave and successive convex-concave shorter wave was described as a 'zero-up-crossing' wave pattern, and the inverse sequence was described as a 'zero-down-crossing' wave pattern. The ripples developed under oscillatory flow with intervening hiatuses manifested the following characteristics in geometry and migration. (i) The morphological characteristics of ripples, namely wavelength, height and the ripple steepness, are unaffected by the intervening hiatuses of velocity. (ii) The directions of ripple migration under the zero-up-crossing and zero-down-crossing wave patterns corresponded well with the directions of the flow immediately before onset of the hiatuses. (iii) The observation of sand particle movement on the ripple surface indicated that, under the zero-up-crossing waves, the velocity hiatus prevents the entrained sediment cloud from being thrown onshore, and thus the sediment grains thrown onshore are fewer than those thrown offshore. As a result of the sediment movement over one wave-cycle, the net sediment transport is directed offshore under the zero-up-crossing wave pattern. (iv) The velocity of ripple migration was highly correlated with acceleration skewness. Under most of the zero-up-crossing (zero-down-crossing) wave patterns, flow acceleration skewed negative (positive) and ripples migrated offshore (onshore)., WILEY-BLACKWELL
SEDIMENTOLOGY, Feb. 2010, [Reviewed]

Cross-shore ripple variations under laboratory partially standing waves: a possible clue to paleo-wavelength
Naofumi Yamaguchi; Tomohiro Sekiguchi and Fujio Masuda, Lead, 日本堆積学会
Journal of the Sedimentological Society of Japan, Apr. 2007, [Reviewed]

書籍紹介 松島 亘志・成瀬 元・横川 美和 編著「土砂動態学―山から深海底までの流砂・漂砂・生態系―」　　　　　　　　　　　　　　　
山口直文
堆積学研究, 16 Feb. 2021
Lead

Center for Water Environment Studies, Ibaraki University　　　　　　　　　　　　　　　
Naofumi Yamaguchi
Journal of the Sedimentary Society of Japan, Feb. 2019

Underwater Investigation for Lake Ashinoko, Kanagawa, Japan by Using a Low-cost Side-scan Sonar Imaging
Shintaro YAMASAKI; Yuki MATSUSHI; Kyoko KATAOKA and Naofumi YAMAGUCHI
京都大学防災研究所年報, Sep. 2017

波浪による振動流下のリップル挙動と堆積構造　　　　　　　　　　　　　　　
山口直文
日本堆積学会2009年京都・枚方大会ショートコース『漂砂流砂系における堆積物動態と地形のとらえ方』講義テキスト, 2009

波はリップルをどう移動させるのか？　　　　　　　　　　　　　　　
山口直文; 関口秀雄
九州大学応用力学研究所研究集会報告：地形のダイナミクスとパターン, 2009
Lead

Ripple formation and grain sorting with multiple-sized sand: a report of preliminary wave-flume experimentation
Naofumi Yamaguchi and Hideo Sekiguchi
DPRI Annuals, May 2007
Lead

堆積学スクール・オン・ザ・ビーチ2006「水理学の基礎と波浪堆積構造」（2006年10月，白浜）参加報告
浦本豪一郎; 清家弘治; 徳田悠希; 西田尚央; 野村真一; 山口直文
堆積学研究, 2006

水路実験による堆積物挙動　　　　　　　　　　　　　　　
増田富士雄; 成瀬元; 高川智博; 齋藤有; 山口直文
日本地質学会第112年学術大会（京都）見学旅行案内書, 2005

フィールドマニュアル 図説 堆積構造の世界
〔総編集〕伊藤 慎,〔編集顧問〕池原 研・高野 修,〔執筆者〕足立奈津子/新井和乃/荒谷 忠/石垣 忍/石原与四郎/伊藤 慎/大野研也/大畑耕治/岡崎浩子/奥村知世/柿崎喜宏/片岡香子/狩野彰宏/鹿野和彦/川上源太郎/川村信人/小竹信宏/後藤和久/小松原純子/近藤康生/齋藤 有/酒井哲弥/佐藤智之/柴田健一郎/白石史人/清家弘治/関口智寛/髙清水康博/田村 亨/中澤 努/中条武司/奈良正和/成瀬 元/西田尚央/藤野滋弘/前野 深/松田博貴/松本 弾/宮田雄一郎/村越直美/八木正彦/山口直文/山下翔大/山田昌樹/山元孝広/横川美和, Contributor
朝倉書店, 01 Jul. 2022
9784254162790

霞ヶ浦北浦における湖底平原への堆積物供給プロセス：粒度分布の成分分離解析による検討　　　　　　　　　　　　　　　
山口直文
日本地球惑星科学連合2024年大会, 28 May 2024
20240526, 20240531

砂泥混合堆積物上の振動流リップル発生条件：粘着性泥と非粘着性泥の比較
山口直文; 松久祐子; 関口智寛; Xuxu Wu; Robert M. Dorrell
日本堆積学会2024年熊本大会, 20 Apr. 2024

霞ヶ浦西浦および北浦における湖底表層堆積物の粒径の特徴：対数正規分布成分への分離による解析　　　　　　　　　　　　　　　
山口 直文・大内 孝雄
日本地質学会日本地質学会第130年学術大会, 18 Sep. 2023, 日本地質学会
20230917, 20230919

多峰性粒度分布から分離された粒径成分の特徴に基づく土砂動態の定量的推定：霞ヶ浦の湖底表層堆積物の例　　　　　　　　　　　　　　　
山口直文・大内孝雄
日本地球惑星科学連合2023年大会, May 2023, 日本地球惑星科学連合
20230521, 20230526

Storegga deposits at Howick Burn and their application to Low Frequency, High Magnitude risk assessment of Offshore Wind　　　　　　　　　　　　　　　
Ben Pickett; Robert M. Dorrell; Jonathan Dean; Hajime Naruse; Naofumi Yamaguchi; Daniel R Parsons
Japan Geoscience Union Meeting 2023, May 2023, Japan Geoscience Union
20230521, 20230526

複雑な粒度分布を分離する際の成分数決定に適した評価基準の検討　　　　　　　　　　　　　　　
山口直文
日本堆積学会2023年新潟大会, 22 Apr. 2023, 日本堆積学会
20230422, 20230424

多峰性粒度分布から分離された粒径成分の特徴と堆積過程への示唆：霞ヶ浦北浦の湖底表層堆積物の例　　　　　　　　　　　　　　　
山口 直文・安藤 毅・榎木田浩孝・中田夏海・八巻 翔太
日本地球惑星科学連合2022年大会, 30 May 2022, 日本地球惑星科学連合
20220522, 20220603

Spatial distribution of microplastics in the Hasaki beach sediments　　　　　　　　　　　　　　　
石澤尭史,後藤和久,山口直文,伴野雅之,篠崎鉄哉,佐藤海生
日本地球惑星科学連合2022年大会, 22 May 2022, 日本地球惑星科学連合
20220522, 20220603

簡便に粒度分布を成分分離する試み　　　　　　　　　　　　　　　
山口直文
日本堆積学会2022年オンライン大会, 23 Apr. 2022, 日本堆積学会
20220423, 20220423

急激な堆積作用による未固結堆積物の液状化・流動化変形：水槽実験による検討　　　　　　　　　　　　　　　
加藤義之・山口直文
日本堆積学会2021年オンライン大会, 14 Nov. 2021, 日本堆積学会
20211113, 20211114

茨城県北浦湖底堆積物中の珪藻殻の破片化率・両殻共存率による堆積過程　　　　　　　　　　　　　　　
組坂健人・岡﨑裕典・山口直文
日本地質学会第128年学術大会, 06 Sep. 2021, 日本地質学会

実験データから明らかになった混濁流と開水路における浮遊砂濃度と乱流構造の違い　　　　　　　　　　　　　　　
福田壮二郎; Elena Bastianon・Bill McCaffrey; 山口直文; 成瀬 元・Robert Dorrell
日本堆積学会2020年オンライン大会, 14 Nov. 2020, 日本堆積学会
20201114

茨城県北浦における珪藻殻の破片化率および両殻共存率　　　　　　　　　　　　　　　
組坂 健人; 岡崎 裕典; 山口 直文
第6回地球環境史学会, 07 Nov. 2020, 地球環境史学会
20201107

異なる粒径の津波堆積物に関する実験的検討：堆積過程と分布傾向の違い　　　　　　　　　　　　　　　
篠崎鉄哉; 山口直文; 関口智寛
2019年度津波堆積物研究会, Aug. 2019

Flume experiments for understanding variety of tsunami deposit　　　　　　　　　　　　　　　
Naofumi Yamaguchi
JpGU Meeting 2019, 30 May 2019, Japan Geoscience Union, [Invited]

Mud vs wave-induced oscillatory flow: preliminary experiment　　　　　　　　　　　　　　　
Naofumi Yamaguchi; Tomohiro Sekiguchi
日本堆積学会2019年大阪大会, 20 Apr. 2019, 日本堆積学会

Characteristics of Sediment Entrainment and Transport Depending on Initial Water Depth under Tsunami-like Bore in Laboratory Experiments　　　　　　　　　　　　　　　
Naofumi Yamaguchi; Takahiro Suzuki; Tetsuya Shinozaki; and Tomohiro Sekiguchi
American Geophysical Union Fall Meeting 2018, Dec. 2018, American Geophysical Union

津波による海底砂の運搬プロセスに関する実験的検討　　　　　　　　　　　　　　　
鈴木貴大; 篠崎鉄哉; 山口直文; 関口智寛
日本堆積学会2018年秋田大会, Mar. 2018, 日本堆積学会

Variety of Sedimentary Process and Distribution of Tsunami Deposits in Laboratory Experiments　　　　　　　　　　　　　　　
Yamaguchi; N. and Tomohiro Sekiguchi
American Geophysical Union Fall Meeting 2017, Dec. 2017, American Geophysical Union

Wave-ripple geometry under sediment supply　　　　　　　　　　　　　　　
滝 俊文; 山口 直文; 関口 智寛
日本地質学会第124年学術大会, Sep. 2017, 日本地質学会

陸上地形が津波堆積物の形成過程と分布に与える影響：水路実験による2つのケース　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本地球惑星科学連合2017年大会, May 2017, 日本地球惑星科学連合

粒径が津波堆積物の分布に及ぼす影響：水路実験による検討　　　　　　　　　　　　　　　
篠崎鉄哉; 関口智寛; 山口直文
日本地球惑星科学連合2017年大会, May 2017, 日本地球惑星科学連合

茨城県霞ヶ浦西浦湖岸平野堆積物への光ルミネッセンス年代測定法の適用　　　　　　　　　　　　　　　
羽田一貴; 伊藤一充; 田村 亨; 山口直文
日本堆積学会2017年松本大会, 25 Mar. 2017, 日本堆積学会

背後に崖がある沿岸低地における津波堆積物の形成過程と分布：水路実験による検討　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本堆積学会2017年松本大会, Mar. 2017, 日本堆積学会

霞ヶ浦西浦湖岸平野堆積物へのpIRIR年代測定法の適用　　　　　　　　　　　　　　　
羽田一貴; 伊藤一充; 田村 亨; 山口直文
日本地質学会第123年学術大会, Sep. 2016, 日本地質学会

霞ヶ浦西浦湖岸平野堆積物のルミネッセンス年代測定　　　　　　　　　　　　　　　
羽田一貴; 伊藤一充; 田村 亨; 山口直文
日本地球惑星科学連合2016年大会, 22 May 2016, 日本地球惑星科学連合

陸上津波堆積物の堆積過程と空間分布：津波規模と地形を考慮した水槽実験による検討　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本地球惑星科学連合2015年大会, May 2015, 日本地球惑星科学連合

水槽実験から見る陸上津波堆積物の形成　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本堆積学会2015年つくば大会, Apr. 2015, 日本堆積学会

湖沼に残された津波堆積物の形成過程と空間分布：水槽実験による検討　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本地球惑星科学連合2014年大会, 30 Apr. 2014, 日本地球惑星科学連合

陸上に遡上した津波の堆積過程：水槽実験による予察的検討　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本堆積学会2014年山口大会, Mar. 2014, 日本堆積学会

Autogenic submarine terrace formed by wave erosion during early stage of sea-level rise: implication from numerical experiments　　　　　　　　　　　　　　　
Yamaguchi; N.
International Workshop Stratodynamics, Aug. 2013

侵食シミュレーションから示唆される海水準変動と不調和な波食地形　　　　　　　　　　　　　　　
山口直文
日本地球惑星科学連合2013年大会, May 2013, 日本地球惑星科学連合

Spatial distribution of wave-dominated sedimentary facies formed in wave-flume experiments　　　　　　　　　　　　　　　
Yamaguchi; N. and Tomohiro Sekiguchi
International Workshop Stratodynamics, Dec. 2012

造波水路実験で形成された前浜－上・下部外浜相の空間分布　　　　　　　　　　　　　　　
山口直文; 関口智寛
日本堆積学会2012年札幌大会, Jun. 2012, 日本堆積学会

2006 - Present, SEPM (Society of Sedimentary Geology)

2006 - Present, International Association of Sedimentologists

2005 - Present, 日本堆積学会

2005 - Present, 日本地球惑星科学連合

2004 - Present, 日本地質学会

ウェーブリップルが地層に残される定量的条件の解明：浅海堆積物から分・秒を読み取る
基盤研究（C）
Apr. 2021 - Mar. 2024

津波による時系列堆積・侵食過程のメカニズム解明と定量的モデルの構築
国際共同研究加速基金(国際共同研究強化(A))
茨城大学
2019 - Mar. 2022

津波による堆積・侵食過程の時系列解析：水理条件の復元に向けた水路実験　　　　　　　　　　　　　　　
若手研究(B)
Apr. 2016 - Mar. 2019

過去の霞ヶ浦湖岸環境の推定に向けた地質学的手法の確立　　　　　　　　　　　　　　　
Apr. 2014 - Mar. 2016

陸上に遡上し湖沼に到達した津波の堆積過程の解明　　　　　　　　　　　　　　　
Apr. 2013 - Feb. 2014

ウェーブリップルの変形過程の解明：形態と水理・粒度条件の相互作用
Others
京都大学
Apr. 2008 - Mar. 2010