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(Table 2) Facies distribution of sediment core CRP-2/2A
No full text(Table 2) Facies distribution of sediment core CRP-2/2
(Table 2) Facies distribution of sediment core CRP-3
No full text(Table 2) Facies distribution of sediment core CRP-
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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Geological insights from the newly discovered granite of Sif island between Thwaites and Pine Island Glaciers
Full text linkLarge-scale geological structures have controlled the long-term development of the bed and thus the flow of the West Antarctic Ice Sheet (WAIS). However, complete ice cover has obscured the age and exact positions of faults and geological boundaries beneath Thwaites Glacier and Pine Island Glacier, two major WAIS outlets in the Amundsen Sea sector. Here, we characterise the only rock outcrop between these two glaciers, which was exposed by the retreat of slow-flowing coastal ice in the early 2010s to form the new “Sif Island”. The island comprises of granite, zircon U-Pb dated to ~177-174 Ma and characterised by initial εNd, 87Sr/86Sr and εHf isotope compositions of -2.3, 0.7061 and -1.3, respectively. These characteristics resemble Thurston Island/Antarctic Peninsula crustal block rocks, strongly suggesting that the Sif Island granite belongs to this province and placing the crustal block’s boundary with the Marie Byrd Land province under Thwaites Glacier or its eastern shear margin. Low temperature thermochronological data reveal that the granite underwent rapid cooling following emplacement, rapidly cooled again at ~100-90 Ma, and then remained close to the Earth’s surface until present. These data help date vertical displacement across the major tectonic structure beneath Pine Island Glacier to the Late Cretaceous
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The Pliocene-Pleistocene Development, Uplift and Emergence History of the Manawatu Strait, New Zealand
No full textThe Manawatu Saddle is located within the structural and topographical low separating the Ruahine and Tararua axial ranges of the lower North Island. Pliocene-Pleistocene sedimentary rocks unconformably drape over Cretaceous aged basement rock in the structural low and record the existence of a paleo seaway known as the Manawatu Strait, which connected the West Coast (Whanganui Basin) to the East Coast (Ruataniwha Strait). The sedimentary sequence shows a succession of alternating marine and terrestrial units recording the development of the Manawatu Strait. These sedimentary rock formations range in age from Opoitian to Castlecliffian.
This study investigates the stratigraphy, lithofacies and resulting geological history of the Manawatu Strait spanning the development, uplift and final emergence history of the strait. Five key measured sections were constructed to take advantage of new outcrop exposure allowed detailed descriptions of the Manawatu Saddle geology to be presented. Four formations are identified and the formation boundary overlaps between past authors is constrained based on field observations. The age range for each formation is also constrained. Based on these results for the first time a detailed lithofacies scheme is applied to the sedimentary rocks within the Manawatu Saddle to understand the changing depositional environments within the Manawatu Strait throughout its development and uplift. A series of 3D schematic paleogeographic figures are presented showing the depositional environments within the Manawatu Strait, at key time intervals.
Results highlighted by this thesis show four major formations within the Manawatu Saddle. The oldest formation, the Mangatoro Formation (Opoitian), records the initial formation of the Manawatu Strait attributed to a regional subsidence event known as the Tangahoe pull down event. The Mangatoro Formation also shows sedimentary deposited during peak marine transgression within the Manawatu Strait. The Te Aute Formation (Waipipian-Mangapanian) provides an insight into the uplift timing of the axial ranges and the resulting effect on the Manawatu Strait. The Kumeroa Formation (Nukumaruan) shows the influence of eustatic sea level change in the Manawatu Saddle. The youngest formation within the Manawatu Saddle is the Mangatarata Formation (Castlecliffian), and marks the final uplift and emergence of the Manawatu Strait, indicated by the presence of marginal marine lithofacies this also marks the final separation of the West Coast (Rauataniwha Strait) and West Coast (Whanganui Basin)
The Early Quaternary Marine to Terrestrial Transition of the Southeastern Wairarapa, New Zealand
No full textThis study examines the final emergence of the southeastern Wairarapa within a
sequence stratigraphic framework. New exposures of the Pleistocene marginalmarine
Hautotara Formation, and non-marine Te Muna Formation allow facies to be
detailed and sequence architecture to be analysed.
Cyclicity observed within the facies successions of the Hautotara and Te Muna
formations are placed in a series of four motifs. These motifs record 40 kyr glacioeustatic
cyclicity superimposed upon the basinward to landward progression of the
environments, showing the region shallowing through time.
The positions of the top of the Pukenui Limestone and the base of the Hautotara
Formation are revised, and are now at the top of the “Pukenui C” - a widespread
marker bed, which also removes a historical nomenclatural gap. The recognition of
the significance of the coccolith Gephyrocapsa sinuosa within the underlying
Pukenui Limestone allows this contact to be dated at 1.73 Ma.
The ~1.6 Ma age limit provided by a number of tephra within the lower sediments of
the Te Muna Formation allow the ages of the examined formations to be constrained
further. The eight 40 ka cycles identified within the Hautotara Formation suggests
deposition between 1.73 and 1.42 Ma.
The Hautotara - Te Muna Formation is revealed to be diachronous, with the base of
the Te Muna Formation type section shown to be much younger, 1.12 Ma, than the
1.58 Ma age of the lower contact observed elsewhere in the region. A series of
palaeogeographic reconstructions at 1.73, 1.58 and 1.57 Ma demonstrate how closely
related sedimentation patterns are to structural growth, with marginal-marine
Hautotara Formation sedimentation persisting in the centre of the study area well
after the initiation of Te Muna Formation terrestrial deposition to the north and south
of this site
Depositional History of Paleocene Sediments in the Offshore Canterbury Basin, New Zealand
No full textThe Paleocene interval within the Canterbury Basin has been relatively understudied with respect to the Neogene and Cretaceous intervals. Within the Paleocene interval is the Tartan Formation and the Charteris Bay Sandstone, which are potential source and reservoir rocks respectively. These two formations have not been previously mapped in the offshore Canterbury Basin and their limits have not been defined. This study utilises a database of nearly 12,000km of 2D seismic data together with data from four open–file wells and sidewall core samples from three wells and newly availiable biostratigraphic information to better constrain the chronostratigraphical interpretation of seismic data. Seismic mapping together with corroboration from well correlation and core lithofacies analysis revealed new insights into the development of the offshore Canterbury Basin through the Paleocene. These include the delineation of the lateral extents and thicknesses of the Tartan Formation and Charteris Bay Sandstone and location of the palaeo shelf–slope break and also the development of a new well correlation panel that incorporates the Tartan Formation for the first time.
This study presents four new paleogeographic maps for the offshore Canterbury Basin that significantly improves our understanding of the development of the basin during the Paleocene. These maps show that during the Earliest Paleocene, the mudstones of the Katiki Formation were being deposited in the south of the study area, with the siltier sediments of the Conway Formation being deposited in the north. The coarser grained Charteris Bay Sandstone was deposited from Early to possibly Middle Paleocene in the northeast. The mudstones of the Moeraki Formation were being deposited in the south at this time. From Middle to Late Paleocene, the mudstones of the Moeraki Formation were deposited in the south and these mudstones onlapped against the Charteris Bay Sandstone which remained as a high in the north. The Tartan Formation was deposited during the Late Paleocene in the central and southern areas of the offshore Canterbury Basin, during a relative fall in sea–level. Deposition had ceased in the north of the study area or erosion possibly removed Late Paleocene sediments from there. During the Latest Paleocene, the mudstones of the Moeraki Formation were deposited over the Tartan Formation in the central and southern parts of the offshore Canterbury Basin with the northern area undergoing erosion, sediment bypass or both
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