Taxonomy, Stratigraphy and Phylogeny of the Middle Miocene Fohsella Lineage: Geometric Morphometric Evidence

2017 ◽  
Vol 47 (4) ◽  
pp. 310-324 ◽  
Author(s):  
Weimin Si ◽  
William A. Berggren
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Reference Points ◽  
Equatorial Pacific Ocean ◽  
Ocean Drilling Program ◽  
Ontong Java Plateau ◽  
Type Specimens ◽  
Widespread Application ◽  
Geometric Morphometric ◽  
Morphologic Variation

Abstract The taxonomy and phylogeny of the planktonic foraminifera Fohsella lineage has been controversial for nearly 50 years, despite its widespread application in Middle Miocene stratigraphy. We have re-examined type specimens of this lineage together with specimens from a continuous deep-sea record (Ocean Drilling Program Site 806, Ontong Java Plateau, western equatorial Pacific Ocean) with an astronomic chronology. Landmark-based geometric morphometry is employed to visualize and quantify morphologic variation within this lineage. Combined morphologic and stratigraphic data help clarify the evolutionary occurrence of diagnostic traits that characterize two problematic taxa, F. praefohsi and F. “praefohsi”, resulting in a revised taxonomy and phylogeny of the lineage. We emphasize the importance of biometric studies of populations from continuous geologic records in establishing taxonomy and phylogeny of planktonic foraminifera. In the past, over-emphasis on the importance of type specimens as reference points in delineating various evolutionary stages of the Fohsella lineage has resulted in inaccurate phylogenetic reconstructions.

scholarly journals Age determinations of Neogene sediments from the English Channel and Western Approaches

1986 ◽  
Vol 5 (1) ◽  
pp. 5-6
Author(s):  
D. Graham Jenkins ◽  
Erlend Martini
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
English Channel ◽  
Calcareous Nannoplankton ◽  
Lower Miocene ◽  
Published Evidence ◽  
Neogene Sediments ◽  
Age Range ◽  
Age Determinations

Abstract. Original published evidence indicated an age range of early Lower Miocene to early Middle Miocene for Globigerina silt samples from the English Channel and the Western Approaches. Suggested younger ages for these samples are refuted on the basis of planktonic foraminifera and calcareous nannoplankton.

Late Neogene–Quaternary Planktic Foraminiferal Biostratigraphy and Biochronology from ODP Site 807A, Ontong Java Plateau, Western Equatorial Pacific

2020 ◽  
Vol 50 (2) ◽  
pp. 111-127
Author(s):  
Tushar Kaushik ◽  
Ashutosh Kumar Singh ◽  
Devesh Kumar Sinha
Keyword(s):  
Equatorial Pacific ◽  
Ocean Drilling Program ◽  
Ontong Java Plateau ◽  
Faunal Turnover ◽  
Ocean Drilling ◽  
Late Neogene ◽  
Western Equatorial Pacific ◽  
Globorotalia Truncatulinoides ◽  
Oceanographic Conditions ◽  
Foraminiferal Biostratigraphy

ABSTRACT A biostratigraphic and biochronological study from the late Neogene–Quaternary section of Ocean Drilling Program (ODP) Site 807A, located on the Ontong Java Plateau, western equatorial Pacific, revealed 50 planktic foraminiferal events, enabling the identification of eight late Neogene–Quaternary biozones, from the Globorotalia plesiotumida Interval Zone to the Globorotalia truncatulinoides Interval Zone. A significant faunal turnover (17 events) from late Pliocene identified in cores 7 and 8, between 70 and 55 meters below seafloor (mbsf), and spanning 0.67 million years (Myr). This noteworthy turnover may be the result of a shift in oceanographic conditions pertaining to the closure of the Indo–Pacific Seaway, followed by the Northern Hemisphere Glaciation. This study provides a high resolution biostratigraphic and biochronological framework for ODP Site 807A that will aid in correlation and timing the various paleoceanographic changes over the last 6 million years in the western equatorial Pacific.

Middle Miocene to Pleistocene Planktonic Foraminiferal Biostratigraphy in the Eastern Equatorial Pacific Ocean

2013 ◽  
Vol 17 (1) ◽  
pp. 91-109 ◽  
Author(s):  
Hiroki Hayashi ◽  
Kyoko Idemitsu ◽  
Bridget S. Wade ◽  
Yuki Idehara ◽  
Katsunori Kimoto ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Middle Miocene ◽  
Equatorial Pacific ◽  
Equatorial Pacific Ocean ◽  
Eastern Equatorial Pacific ◽  
Eastern Equatorial Pacific Ocean ◽  
Foraminiferal Biostratigraphy

scholarly journals Research and Application of Underground WLAN Adaptive Radio Fingerprint Database

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1182
Author(s):  
Jiansheng Qian ◽  
Mingzhi Song
Keyword(s):  
Signal Strength ◽  
Access Point ◽  
Received Signal Strength ◽  
Reference Points ◽  
Normal Operation ◽  
Positioning System ◽  
Widespread Application ◽  
Radio Fingerprint ◽  
Fingerprint Database ◽  
User Location

Fingerprint positioning based on WiFi in coal mines has received much attention because of the widespread application of WiFi. Fingerprinting techniques have developed rapidly due to the efforts of many researchers. However, the off-line construction of the radio fingerprint database is a tedious and time-consuming process. When the underground environments change, it may be necessary to update the signal received signal strength indication (RSSI) of all reference points, which will affect the normal working of a personnel positioning system. To solve this problem, an adaptive construction and update method based on a quantum-behaved particle swarm optimization–user-location trajectory feedback (QPSO–ULTF) for a radio fingerprint database is proposed. The principle of ULTF is that the mobile terminal records and uploads the related dataset in the process of user’s walking, and it forms the user-location track with RSSI through the analysis and processing of the positioning system server. QPSO algorithm is used for the optimal radio fingerprint match between the RSSI of the access point (AP) contained in the dataset of user-location track and the calibration samples to achieve the adaptive generation and update of the radio fingerprint samples. The experimental results show that the radio fingerprint database generated by the QPSO–ULTF is similar to the traditional radio fingerprint database in the statistical distribution characteristics of the signal received signal strength (RSS) at each reference point. Therefore, the adaptive radio fingerprint database can replace the traditional radio fingerprint database. The comparable results of well-known traditional positioning methods demonstrate that the radio fingerprint database generated or updated by the QPSO–ULTF has a good positioning effect, which can ensure the normal operation of a personnel positioning system.

Abyssal benthic foraminifera in the eastern equatorial Pacific (IODP EXP 320) during the middle Eocene

2013 ◽  
Vol 87 (6) ◽  
pp. 1160-1185 ◽  
Author(s):  
Hiroyuki Takata ◽  
Ritsuo Nomura ◽  
Akira Tsujimoto ◽  
Boo-Keun Khim ◽  
Ik Kyo Chung
Keyword(s):  
Water Depth ◽  
Benthic Foraminifera ◽  
Middle Eocene ◽  
Accumulation Rate ◽  
Equatorial Pacific ◽  
Equatorial Pacific Ocean ◽  
Ocean Drilling Program ◽  
Integrated Ocean Drilling Program ◽  
Eastern Equatorial Pacific ◽  
Study Interval

We report on the faunal transition of benthic foraminifera during the middle Eocene at Site U1333 (4862 m water depth, 3,560–3,720 m paleo-water depth) of Integrated Ocean Drilling Program Expedition 320 in the eastern equatorial Pacific Ocean. During the period ∼41.5–40.7 Ma, which includes carbonate accumulation event 3 (CAE-3), the benthic foraminiferal accumulation rate (BFAR) increased gradually and then it declined rapidly. In contrast, BFAR was considerably lower during ∼40.7–39.4 Ma, corresponding to the middle Eocene climatic optimum (MECO), and then it increased during ∼39.3–38.4 Ma, including CAE-4. Diversity (E [S200]) was slightly lower in the upper part of the study interval than in the lower part. The most common benthic foraminifera were Nuttallides truempyi, Oridorsalis umbonatus, and Gyroidinoides spp. in association with Globocassidulina globosa and Cibicidoides grimsdalei during the period studied. Quadrimorphina profunda occurred abundantly with N. truempyi, O. umbonatus, and G. globosa during ∼39.4–38.4 Ma, including CAE-4, although this species was also relatively common in the lower part of the study interval. Virgulinopsis navarroanus and Fursenkoina sp. A, morphologically infaunal taxa, were common during ∼38.8–38.4 Ma, corresponding to the late stage of CAE-4. Based on Q-mode cluster analysis, four sample clusters were recognized and their stratigraphic distributions were generally discriminated in the lower and upper parts of the study interval. Thus, there was only a small faunal transition in the abyssal eastern equatorial Pacific during the middle to late-middle Eocene. The faunal transition recognized in this study may be related to recovery processes following intense carbonate corrosiveness in the eastern equatorial Pacific during MECO.

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