(Table 2) Taxonomic composition of diatoms in dredged samples from the island-side slope of the Kuril-Kamchatka Trench

• Main Author: Tsoy, Ira B
• Format: Dataset
• Language: English
• Published: PANGAEA 2002
• Subjects: Actinoptychus intermedius; Actinoptychus senarius; Actinoptychus spp.; Actinostephanos rudis; Anaulus acutus; Arachnoidiscus ehrenbergii; Arachnoidiscus sp.; Archive of Ocean Data; ARCOD; Asterolampra punctifera; Asterolampra schmidtii; Asteromphalus oligocenicus; Asteromphalus spp.; Aulacodiscus affinis; Aulacodiscus brownii; Azpeitia oligocenica; Azpeitia spp.; Azpeitia tabularis; Biddulphia rigida; Biddulphia spp.; Calculated; Cavitatus jouseanus; Cavitatus linearis; Cavitatus miocenicus; Cavitatus rectus; Cestodiscus kugleri; Cestodiscus mukhinae; Cestodiscus spp.; Chaetoceros spp.; Chasea bicornis; Chasea ornata; Clavicula arenosa; Cocconeis antiqua; Cocconeis californica; Cocconeis vitrea; Coscinodiscus argus; Coscinodiscus asteromphalus; Coscinodiscus hajosiae; Coscinodiscus marginatus; Coscinodiscus oculus-iridis; Coscinodiscus radiatus; Coscinodiscus sectoralis; Coscinodiscus spp.; Counting; diatoms; Craspedodiscus sp.; Cymatosira lorenziana; Diatom zone; Dicladia sp.; Diploneis sp.; Pacific; Kamchatka
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.763621; https://doi.org/10.1594/PANGAEA.763621

Studies of diatoms from dredge samples collected on the island slope of the Kuril-Kamchatka Trench have allowed to recognize well-preserved marine diatom assemblages corresponding to assemblages of the followed Oligocene zones: Rhizosolenia oligocaenica (subzone ''a'', 33.6-31 Ma), Cavitatus rectus (29.6-28.2 Ma), and Rocella gelida (28.2-24.0 Ma) as identified in the North Pacific zonal scale. Description of these assemblages and their complete taxonomic composition are presented. Diversity of species together with abundance and degree of preservation of diatoms and accompanying siliceous microorganisms suggests their autochtonous origin and favorable conditions of their development. Assemblages of the Early Oligocene zones Rhizosolenia oligocaenica and Cavitatus rectus recognized in sediments of the outer zone of the Lesser Kuril Ridge (submarine slope of the Shikotan Island) and on the Vityaz' submarine ridge were most probably formed under conditions of a vast shelf, while assemblage of the Late Oligocene zone Rocella gelida encountered only in the region of the Lesser Kuril Ridge formed under more deep-water conditions, presumably, over an island slope. Deepening of the basin in the region of the outer zone of the Lesser Kuril Ridge in Late Oligocene probably reflects one of stages of evolution of the Kuril-Kamchatka Trench.