Duho Formation

Duho Formation
Stratigraphic range: Middle Miocene
~
TypeGeological formation
Unit ofYeonil Group
UnderliesAlluvium
OverliesHagjeon Formation
Thickness150–250 m (490–820 ft)[1]
Lithology
PrimaryMudstone
OtherSandstone, Shale
Location
Coordinates36°00′N 129°12′E / 36.0°N 129.2°E / 36.0; 129.2
RegionNorth Gyeongsang Province
CountrySouth Korea
ExtentPohang Basin (ko:포항 분지)
Type section
Named forDuho-dong
Named byUm et al., 1964[2]

Geological map and stratigraphy of the Pohang Basin

The Duho Formation (Korean: 두호층; Hanja: 斗湖層; RR: Duho-cheung) is a Middle Miocene geological formation in Pohang, South Korea. This formation is deposited in a deep marine environment and is roughly dated to around 15 to 12 million years ago based on various analyses. It is the uppermost unit of the Yeonil Group of Pohang Basin and mainly composed of yellow-brown to dark gray mudstones.[3]

Geology

The deposition of the Pohang Basin began some time after 21.89 to 21.68 million years ago, corresponding to the Early Miocene, based on zircon U-Pb dating.[4] This deep-marine basin was probably produced by rapid subsidence around 17 million years ago, following the abrupt ending of the strike-slip deformation and volcanic activity, and experienced tectonic inactivity for 5 to 7 million years until the crustal uplift in southeastern Korea around 10 million years ago which caused the sedimentation to cease.[5] The basin was likely a pelagic zone around 17.6 to 11.5 million years ago based on biostratigraphy analysis.[6]

The intrusive basalt of the Yeonil Group from the southern part of the basin is dated to the lower Middle Miocene around 15.16 to 14.82 million years ago based on K-Ar dating,[7] which implies the evolution of back-arc basin in the seas of southeastern Korea, followed by the tectonic inversion which changed the geodynamic setting and basaltic magma composition.[8] Paleomagnetic dating (analysis of the sediments' ancient magnetic fields) of the Duho Formation yielded the age estimate ranging from 14.7 to 11.6 million years ago.[9] The age estimate of the Yeonil Group based on the same technique is around 17.3 to 11.3 million years ago for the lower and upper part respectively with a reliable pole position of 15 million years ago, while biostratigraphy analysis indicated that the age of the Duho Formation likely ranged from 14 to 12 million years ago.[10] It is probably not younger than 11.95 million years ago based on the radiolarians recovered from the formation.[11]

Paleoecology

Notable fossils from the Duho Formation include a variety of aquatic invertebrates such as ophiuroids, bivalves and mantis shrimps, numerous extant genera of plants, indeterminate remains of toothed whales with some diagnostic to the genus level, and diverse ichthyofauna ranging from small bony fish to large cartilaginous fish like the giant lamniform shark Otodus megalodon which would have been the apex predator of the Miocene seas of Korea. While the fauna consists of species ranging from the shallow coastal waters (neritic and epipelagic zone) to the depths of over 1,000 metres (3,300 ft) (bathypelagic zone), the sediments were probably deposited in a pelagic deep-water setting as evidenced by the paleoecological and bathymetric features of the fossil assemblage.[1]

Fossil content

Arthropods

The probable ant fossil named as Aphaenogaster "koreana" in a 2018 conference abstracts is a nomen nudum.[12]

Arthropods of the Duho Formation[13][14]
Genus Species Region Member Material Notes Image
Leesquilla
  • L. bajee
  • L. sunii
 Mantis shrimp belonging to the family Squillidae
Pohsquilla
  • P. neonica
  • P. scissodentica
 Mantis shrimp belonging to the family Squillidae
Squilla S. sp. Mantis shrimp belonging to the family Squillidae
Scarites S. sp. First officially described terrestrial animal (ground beetle) from the deep marine Duho Formation

Echinoderms

The probable sea urchin fossil named as Brissopsis "pohangensis" in a 2015 doctoral thesis is a nomen ex dissertationae.[15]

Echinoderms of the Duho Formation[16]
Genus Species Region Member Material Notes Image
Ophiura O. pohangensis Brittle star fossils previously described from the same formation are probably conspecific with O. pohangensis

Molluscs

Molluscs of the Duho Formation[17]
Genus Species Region Member Material Notes Image
Acharax A. tokunagai
Conchocele C. bisecta
Delectopecten D. peckhami
Lucinoma
  • L. acutilineatum
  • L. sp.
Macoma M. incongrua
Mizuhopecten M. kimurai ugoensis Reported as Patinopecten kimurai ugoensis,[18] but this species was already moved to a different genus Mizuhopecten by Mausda (1963)[19]
Nuculana N. pennula
Panomya P. simotomensis
Patinopecten P. sp.
Phos P. cf. minoensis
Portlandia P. cf. gratiosa
Propeamussium P. tateiwai
Squiresica[20] S. yooni Vesicomyid bivalve mollusc fossil originally assigned to as Calyptogena cf. elongata
Yoldia Y. sagittaria

Mammals

Mammals of the Duho Formation
Genus Species Region Member Material Notes Image
Kentriodontidae[21] Indeterminate Partial maxilla (DWFM 10001) Extinct family of toothed whales
Pomatodelphininae[22] Indeterminate Partial rostrum and mandible (KIGAM VP 201101) River dolphin found in marine deposits and related to Pomatodelphis
Tursiops[23] T. sp. Partial skeleton measuring 70 cm (2.3 ft) long, with a nearly complete skull Resembles the modern bottlenose dolphin with the estimated complete length of the specimen around 1.5–2 m (4.9–6.6 ft)
Kogia[23] K. sp. Partial skull measuring 40 cm (1.3 ft) long, associated with the tooth of an adult tiger shark Resembles the modern pygmy sperm whale and dwarf sperm whale

Bony fish

Bony fish of the Duho Formation
Genus Species Region Member Material Notes Image
Auxis
  • Two fragmentary, disarticulated specimens distinguished from the extant species by the osteological differences in the skull
  • Partial caudal vertebrae (GNUE322001) associated with a leaf imprint
 First and second fossil record of the genus Auxis in Korea
Cyclothone[26] C. duhoensis The oldest nominal species of Cyclothone
Pleuronectiformes[27] Indeterminate First record of flatfish from this formation
Pleuronichthys[28] P. sp.
Stenobrachius[29] S. sangsunii Lanternfish
Vinciguerria[30] V. orientalis Distinct from modern species of Vinciguerria in terms of caudal skeleton structure
Zaprora[31] Z. koreana Second fossil record of the family Zaproridae

Cartilaginous fish

The record of Otodus obliquus from this formation is most likely a misidentification of other otodontid or lamniform shark.[32]

Cartilaginous fish of the Duho Formation[1]
Genus Species Region Member Material Notes Image
Carcharhinus
  • C. aff. C. plumbeus
  • C. aff. C. amblyrhynchos
  • C. aff. C. altimus
 Teeth
Cetorhinus C. huddlestoni[33] Gill rakers and oral tooth mold
Cosmopolitodus
  • C. hastalis
  • C. planus
 Teeth Uncertain whether it is a distinct genus or a junior synonym of Carcharodon
Dalatias D. orientalis Teeth Two teeth originally assigned to as D. licha (CNUNHM-F279) and D. cf. licha (CNUNHM-F392) respectively are now the paratypes of D. orientalis
Galeocerdo G. aduncus Teeth
Hexanchus H. griseus Tooth Miocene record of the modern bluntnose sixgill shark
Isurus
  • I. sp. 1
  • I. sp. 2
 Teeth
Mitsukurina M. owstoni Teeth Among the oldest known record of the modern goblin shark; one tooth (CNUNHM-F268) was originally assigned to as M. cf. lineata
Otodus O. megalodon Teeth Largest known macropredatory shark that ever lived
Parotodus P. benedenii Tooth

Plants

Plants of the Duho Formation
Genus Species Region Member Material Notes Image
Acer[34][35]
  • A. ezoanum
  • A. huziokae
  • A. nordenskioeldi
  • A. palaeoplatanoides
  • A. pohangense
  • A. protomiyabei
  • A. prototrifidium
  • A. pseudoginnala
  • A. rotundatum (=A. subpictum & A. pictum)
Alangium[36] A. aequalifolium
Albizia[37] A. miokalkora
Castanea[36] C. tanaii
Castanopsis[36] C. pohangensis
Carpinus[38][36]
  • C. hokoensis
  • C. kodairae-bracteata
  • C. miofargesiana
  • C. oblongibracteata
  • C. stenophylla
  • C. subcordata
Cinnamomum[36] C. lanceolatum
Cryptocarya[36] C. ennichiensis
Cunninghamia[39] C. protokonishii
Cyclobalanopsis[36]
  • C. huziokai
  • C. mandraliscae
  • C. yabei
Dipteronia[40] D. brownii
Entada[36] E. mioformosana
Fagus[36] F. cf. hayate
Firmiana[41] F. sinomiocenica
Fraxinus[42][36]
  • F. oishii
  • F. insularis
  • F. sp.
Ilex[43] I. protocornuta
Keteleeria[44] K. ezoana
Hemitrapa[36] H. yokoyamae Extinct genus of aquatic plants related to water caltrop
Lindera[36] L. gaudini
Liriodendron[42] L. meisenense
Liquidambar[36] L. miosinica
Paliurus[36] P. koreanus
Pasania[36]
  • P. miohypophaea
  • P. protokonishii
Parrotia[36] P. fagifolia
Phoebe[36] P. mioformosana
Picea[44] P. kaneharai
Pinus[44]
  • P. miocenica
  • P. cf. prekesiya
Platanus[36] P. guillelmae
Pseudolarix[45]
  • P. japonica
  • P. sp. A
  • P. sp. B
Pterocarya[36] P. asymmetrosa
Rhododendron[36] R. tatewakii
Tilia[41] T. asiatica
Zelcova[36] Z. ungeri

Ichnofossils

Ichnofossils of the Duho Formation[46]
Genus Species Region Member Material Notes Image
Chondrites
  • C. isp. 1
  • C. isp. 2
 Three deep-water ichnofossils C. isp. 1 and C. isp. 2 are deposited under oxygen-depleted and oxygenated conditions respectively
Palaeophycus P. isp.
Planolites P. isp.
Taenidium T. isp.

References

  1. ^ a b c Malyshkina, T.P.; Ward, D.J.; Nazarkin, M.V.; Nam, G.-S.; Kwon, S.-H.; Lee, J.-H.; Kim, T.-W.; Kim, D.-K.; Baek, D.-S. (2023). "Miocene Elasmobranchii from the Duho Formation, South Korea". Historical Biology. 35 (9): 1726–1741. Bibcode:2023HBio...35.1726M. doi:10.1080/08912963.2022.2110870.
  2. ^ Um, S.H.; Lee, D.W.; Bak, B.S. (1964). "Explanatory text of the geological map of Pohang sheet". Geological Survey of Korea: 1–38.
  3. ^ Yun, C.-G. (2022). "A Tooth Of The Extinct Lamnid Shark, Cosmopolitodus planus Comb. Nov. (Chondrichthyes: Elasmobranchii) From The Miocene Of Pohang City, South Korea" (PDF). Acta Palaeontologica Romaniae. 18 (1): 9–16. doi:10.35463/j.apr.2022.01.02.
  4. ^ Lee, T.H.; Yi, K.; Cheong, C.S.; Jeong, Y.J.; Kim, N.; Kim, M.J. (2014). "SHRIMP U-Pb Zircon Geochronology and Geochemistry of Drill Cores from the Pohang Basin". Journal of Petrological Society of Korea. 23 (3): 167–185. doi:10.7854/JPSK.2014.23.3.167.
  5. ^ Sohn, Y.K.; Rhee, C.W.; Shon, H. (2001). "Revised stratigraphy and reinterpretation of the Miocene Pohang basinfill, SE Korea: sequence development in response to tectonism and eustasy in a back-arc basin margin". Sedimentary Geology. 143 (3–4): 265–285. Bibcode:2001SedG..143..265S. doi:10.1016/S0037-0738(01)00100-2.
  6. ^ Kim, W.H. (1990). "Significance of early to middle Miocene planktonic foraminiferal biostratigraphy of the E-core in the Pohang Basin, Korea". Journal of the Paleontological Society of Korea. 6: 144–164.
  7. ^ Lee, H.K.; Moon, H.-S.; Min, K.D.; Kim, I.-S.; Yun, H.; Itaya, T. (1992). "Paleomagnetism, stratigraphy and geologic structure of the Tertiary Pohang and Changgi basins; K-Ar ages for the volcanic rocks" (PDF). Journal of the Korean Institute of Mining Geology. 25 (3): 337–349.
  8. ^ Son, M.; Song, C.W.; Kim, M.-C.; Cheon, Y.; Cho, H.; Sohn, Y.K. (2015). "Miocene tectonic evolution of the basins and fault systems, SE Korea: dextral, simple shear during the East Sea (Sea of Japan) opening". Journal of the Geological Society. 172 (5): 664–680. Bibcode:2015JGSoc.172..664S. doi:10.1144/jgs2014-079.
  9. ^ Kim, K.H.; Doh, S.J.; Hwang, C.S.; Lim, D.S. (1993). "Paleomagnetic Study of the Yeonil Group in Pohang Basin" (PDF). Journal of Korean Society of Economic and Environmental Geology. 26: 507–518.
  10. ^ Lee, Y.S.; Ishikawa, N.; Kim, W.K. (1999). "Paleomagnetism of Tertiary rocks on the Korean Peninsula: tectonic implications for the opening of the East Sea (Sea of Japan)". Tectonophysics. 304 (1–2): 131–149. Bibcode:1999Tectp.304..131L. doi:10.1016/S0040-1951(98)00270-4.
  11. ^ Bak, Y.; Lee, J.D.; Yun, H. (1996). "Middle Miocene Radiolarians from the Duho Formation in the Pohang Basin, Korea". Journal of the Paleontological Society of Korea. 12 (2): 225–261.
  12. ^ Dong, M.; Kim, S.; Nam, K.S. (2018). First record of gyne fossil Aphaenogaster (Hymenoptera: Formicidae: Myrmicinae) from Eastern Palaearctic Region. 2018 Spring International Conference of the Korean Society of Applied Entomology. p. 73.
  13. ^ Yun, H. (1985). "Some fossil Squillidae (Stomatopoda) from the Pohang Tertiary Basin, Korea". Journal of the Paleontological Society of Korea. 1: 19–31.
  14. ^ Lee, S.B.; Nel, A.; Nam, G.S. (2024). "The first fossil Scarites (Coleoptera: Carabidae) from the Duho Formation (middle Miocene), Korean Peninsula". Palaeoworld. 33 (4): 1119–1127. Bibcode:2024Palae..33.1119L. doi:10.1016/j.palwor.2023.05.002.
  15. ^ Lee, B.J. (2015). Cenozoic echinoderms from the Pohang Basin, Korea (PhD thesis). Daegu: Kyungpook National University. pp. 1–164.
  16. ^ Ishida, Y.; Thuy, B.; Nam, G.-S.; Martynov, A.; Fujita, T.; Kim, J.-H. (2022). "A New Species of Ophiura (Echinodermata, Ophiuroidea) from Miocene Deep-Sea Deposits in the Pohang Basin, Korea". Paleontological Research. 26 (1): 18–30. Bibcode:2022PalRe..26.0002I. doi:10.2517/PR200002. S2CID 245478821.
  17. ^ Kim, S.-H.; Park, J.-Y.; Lee, Y.-N. (2018). "A tooth of Cosmopolitodus hastalis (Elasmobranchii: Lamnidae) from the Duho Formation (Middle Miocene) of Pohang-si, Gyeongsangbuk-do, South Korea". Journal of the Geological Society of Korea. 54 (2): 121–131. doi:10.14770/jgsk.2018.54.2.121. ISSN 2288-7377.
  18. ^ Kim, D.H.; Lee, S.J. (2011). "Fossil scallops from the Hagjeon Formation and the Duho Formation, Pohang Basin". Journal of the Geological Society of Korea. 47 (3): 235–244.
  19. ^ Matsubara, T. (2011). "Miocene shallow marine molluscs from the Hokutan Group in the Tajima area, Hyôgo Prefecture, southwest Japan" (PDF). Bulletin of the Mizunami Fossil Museum (37): 51–113.
  20. ^ Kiel, S.; Amano, K.; Goedert, J. (2023). "New taxa, records, and data for vesicomyid bivalves from Cenozoic strata of the North Pacific region" (PDF). Acta Palaeontologica Polonica. 68 (2): 297–320. doi:10.4202/app.01061.2023.
  21. ^ Lim, J.-D. (2005). "The first dolphin fossil from the Miocene of Korea". Current Science. 89 (6): 939–940. JSTOR 24110745.
  22. ^ Lee, Y.-N.; Ichishima, H.; Choi, D.K. (2012). "First record of a platanistoid cetacean from the middle Miocene of South Korea". Journal of Vertebrate Paleontology. 32 (1): 231–234. Bibcode:2012JVPal..32..231L. doi:10.1080/02724634.2012.626005. S2CID 129560068.
  23. ^ a b Min, J.Y. (2013). A study on the Suborder Odontoceti from the Duho Formation in the Pohang Basin, Korea (MSc thesis) (in Korean). Gwangju: Chonnam National University. pp. 1–92.
  24. ^ Nam, G.S.; Nazarkin, M.V.; Bannikov, A.F. (2021). "First discovery of the genus Auxis (Actinopterygii: Scombridae) in the Neogene of South Korea". Bollettino della Società Paleontologica Italiana. 60 (1): 61–67. doi:10.4435/BSPI.2021.05 (inactive 18 February 2025).{{cite journal}}: CS1 maint: DOI inactive as of February 2025 (link)
  25. ^ Suh, D.; Kim, S.-H.; Nam, G.-S. (2024). "A new tuna specimen (Genus Auxis) from the Duho Formation (Miocene) of South Korea". bioRxiv 10.1101/2024.07.29.605724.
  26. ^ Nam, Gi-Soo; Nazarkin, Mikhail V. (2021). "A Neogene bristlemouth of the genus Cyclothone (Stomiiformes: Gonostomatidae) from South Korea". Historical Biology. 33 (11). e1625911. Bibcode:2021HBio...33.2639N. doi:10.1080/08912963.2020.1820000.
  27. ^ Ko, J.Y. (2016). "The description of the flat fish (Pleuronectiformes) fossils from the Miocene Duho Formation, Pohang Yeonam-dong in Korea and its implication" (PDF). Journal of the Korean Earth Science Society. 37 (1): 1–10. doi:10.5467/JKESS.2016.37.1.1.
  28. ^ Ko, J.Y.; Nam, K.S. (2016). "Pleuronichthys sp. Fossils (Pleuronectidae) from the Duho Formation, Pohang Uhyeon-dong in Korea" (PDF). Journal of the Korean Earth Science Society. 37 (3): 133–142. doi:10.5467/JKESS.2016.37.3.133.
  29. ^ Nam, Gi-Soo; Nazarkin, Mikhail V. (2022). "A new lanternfish (Myctophiformes, Myctophidae) from the Middle Miocene Duho Formation, South Korea". Journal of Vertebrate Paleontology. 42 (1). e2121924. Bibcode:2022JVPal..42E1924N. doi:10.1080/02724634.2022.2121924.
  30. ^ Kye-Soo Nam; Ju-Yeong Ko; Mikhail V. Nazarkin (2019). "A new lightfish, †Vinciguerria orientalis, sp. nov. (Teleostei, Stomiiformes, Phosichthyidae), from the middle Miocene of South Korea". Journal of Vertebrate Paleontology. 39 (3). e1625911. Bibcode:2019JVPal..39E5911N. doi:10.1080/02724634.2019.1625911. S2CID 199637854.
  31. ^ Nam, Kye-Soo; Nazarkin, Mikhail V. (2018). "Fossil prowfish, Zaprora koreana, sp. nov. (Pisces, Zaproridae), from the Neogene of South Korea". Journal of Vertebrate Paleontology. 38 (5). e1514616. Bibcode:2018JVPal..38E4616N. doi:10.1080/02724634.2018.1514616.
  32. ^ Yun, C. (2020). "New example of Cosmopolitodus hastalis (Lamniformes, Lamnidae) from the Miocene South Korea". Zoodiversity. 54 (5): 433–438. doi:10.15407/zoo2020.05.433. S2CID 229274996.
  33. ^ Malyshinka, T.P.; Nam, G.-S.; Kwon, S.-H. (2021). "Basking Shark Remains (Lamniformes, Cetorhinidae) from the Miocene of South Korea". Journal of Vertebrate Paleontology. 41 (5). 247466156. Bibcode:2021JVPal..41E7625M. doi:10.1080/02724634.2021.2037625.
  34. ^ Kim, J.-H.; Nam, K.-S.; Jeon, Y.-S. (2017). "Diversity of Miocene fossil Acer from the Pohang Basin, Korea". Journal of the Geological Society of Korea. 53 (3): 387–405. doi:10.14770/jgsk.2017.53.3.387. S2CID 133816740.
  35. ^ Kim, J.H. (2008). "A new species of Acer samara from the Miocene Yeonil Group in the Pohang Basin, Korea". Geosciences Journal. 12 (4): 331–336. Bibcode:2008GescJ..12..331K. doi:10.1007/s12303-008-0033-6.
  36. ^ a b c d e f g h i j k l m n o p q r s t u Lim, J.-D. (2010). "Miocene woods of the Janggi Basin in Korea: Implications for paleofloral changes". Geosciences Journal. 14 (1): 11−22. Bibcode:2010GescJ..14...11L. doi:10.1007/s12303-010-0002-8.
  37. ^ Kim, J.-H. (2010). "Albizia miokalkora Hu and Chaney from the Duho Formation of Yeonil Group (Miocene) in the Pohang Basin, Korea". Journal of Korean Earth Science Society. 31 (7): 691–697. doi:10.5467/JKESS.2010.31.7.691. S2CID 128610278.
  38. ^ Kim, J.-H.; Nam, K.-S. (2017). "Fossil involucres of Carpinus and their significances from the Duho Formation of Yeonil Group, Korea". Journal of the Geological Society of Korea. 53 (6): 759–772. doi:10.14770/jgsk.2017.53.6.759.
  39. ^ Yabe, A.; Yamakawa, C. (2017). "Revision of Cunninghamia protokonishii Tanai et Onoe (Pinopsida, Cupressaceae) from East Asia". Paleontological Research. 21 (4): 309–328. Bibcode:2017PalRe..21..309Y. doi:10.2517/2016PR032.
  40. ^ Jia, L.-B.; Nam, G.-S.; Su, T.; Yang, X.; Zhou, Z.-K.; Ji, Y.-H. (2023). "Miocene Dipteronia (Sapindaceae) samaras from South Korea and their biogeographical implications". iScience. 26 (4). 106515. Bibcode:2023iSci...26j6515J. doi:10.1016/j.isci.2023.106515. ISSN 2589-0042. PMC 10105288. PMID 37070070.
  41. ^ a b Jia, L.B.; Nam, G.S.; Su, T.; Stull, G.W.; Li, S.F.; Huang, Y.J.; Zhou, Z.K. (2021). "Fossil fruits of Firmiana and Tilia from the middle Miocene of South Korea and the efficacy of the Bering land bridge for the migration of mesothermal plants". Plant Diversity. 43 (6): 480–491. Bibcode:2021PlDiv..43..480J. doi:10.1016/j.pld.2020.12.006. PMC 8720707. PMID 35024517.
  42. ^ a b Jung, S.H.; Lee, S.J. (2009). "Fossil winged fruits of Fraxinus (Oleaceae) and Liriodendron (Magnoliaceae) from the Duho Formation, Pohang Basin, Korea". Acta Geologica Sinica - English Edition. 83 (5): 845–852. Bibcode:2009AcGlS..83..845J. doi:10.1111/j.1755-6724.2009.00113.x.
  43. ^ Li, X.-Y.; Nam, G.-S.; Li, S.-F.; Averyanova, A.; Yang, Y.; Yoon, M.-B.; Jia, L.-B. (2025). "Fossil evidence and ecological niche modelling reveal trait evolution and biogeography of the Ilex cornuta lineage". Journal of Palaeogeography. doi:10.1016/j.jop.2025.02.003.
  44. ^ a b c Kim, J.-H.; Nam, G.S.; Kim, J.-M. (2021). "Some Pinaceae from the Miocene Duho Formation (Yeonil Group) in the Pohang basin, Korea". Journal of the Geological Society of Korea. 57 (1): 1–16. doi:10.14770/jgsk.2021.57.1.1.
  45. ^ Kim, J.H. (2009). "Occurrence of Pseudolarix (Pinaceae) from the Miocene Duho Formation of the Yeonil Group, Korea". Journal of Korean Earth Science Society. 30 (5): 598–604. doi:10.5467/JKESS.2009.30.5.598. S2CID 128845781.
  46. ^ Kim, J.; Paik, I.S (2013). "Chondrites from the Duho Formation (Miocene) in the Yeonil Group, Pohang Basin, Korea: Occurrences and paleoenvironmental implications". Journal of the Geological Society of Korea. 49 (3): 407–416.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.