On the correlation and classification of Quaternary deposits and land-sea correlations

Keyword(s):  
2002 ◽  
Vol 4 (1-2) ◽  
pp. 153-164 ◽  
Author(s):  
Frans GULLENTOPS ◽  
Frieda BOGEMANS ◽  
Guy De MOOR ◽  
Etienne PAULISSEN ◽  
Albert PISSART

The lithostratigraphic classification of the Quaternary deposits is based on the genesis of the sediments. The distinguished environments are marine - estuarine, fluvial, eolian and slope. The marine - estuarine deposits are restricted to certain time-intervals within the Quaternary and are limited to the northern part of Belgium. Fluvial deposits are found throughout the Quaternary. On the basis of the sedimentological - lithological differentials within the Meuse basin and the Schelde basin a bipartite subdivision of the fluvial deposits is introduced. Eolian deposits are differentiated on the basis of their grain size distribution, namely sand and silt. The sandy deposits are accumulated in the northern part of Belgium, whereas loess is deposited in the more southern part of the country. Slope deposits are not restricted regionally neither temporally.


2017 ◽  
Vol 50 (1) ◽  
pp. 55 ◽  
Author(s):  
G.D. Koufos

Most basins of Greece were filled with thick Neogene-Quaternary continental deposits, which include a large number of mammal fossiliferous sites. The investigations of the last 40 years in the various basins of Greece led to the discovery of many new fossiliferous sites. The extensive, long time and continuous excavations in the new fossiliferous sites as well as in the previously known ones - like the classical localities of Axios Valley, Pikermi and Samos Island - provided numerous fossils enriching remarkably the Greek fossil mammal record. The systematic study of these collections provided numerous data for their biochronology. Further magnetostratigraphic, radiometric or other methods of absolute chronology provided additional chronological data for the mammal faunas and the corresponding deposits. The correlation of all these data allowed the biostratigraphic classification of the continental Neogene Quaternary deposits of Greece which is given in the biostratigraphic tables of the present article. From these tables it is clear that for some time-intervals (Late Miocene, Early Pleistocene) the data are abundant allowing a detailed biostratigraphy, but for some others (Early- Middle Miocene, Pliocene, and for some time-spans of Early Pleistocene) the data are  imited or missing and cannot allow an accurate and complete biostratigraphy.


Author(s):  
Nazar Rybak

The morphodynamic classification of the Sukil river channel made it possible to determine the hydromorphological processes and to study the factors that determine them. The channel was classified according to the method of R.S. Chalov. Three main classification criteria were taken into account: the geomorphological type of conditions for the formation of the channel; the type of channel processes; the mophrodynamic type of channel. According to the geomorphological type of channel-forming conditions, the channel is divided into the incised channel – located mainly in mountainous and semi-mountainous parts with a characteristic the narrow valley, laid in sandstones, siltstones, and argillites; confined channel – located in intermountain basins, with one bank of channel composed of bedrock, and the other – of Quaternary sediments; wide-floodplain channel – mainly located in the lower part of the channel on the Stryi-Zhydachiv basin, laid in the Quaternary deposits of loams and sands. According to the type of channel processes, the channels with developed alluvial forms and without developed alluvial forms are dominant. Together they make up 2/3 of the channel. Other types of channels are wide-floodplain – characterized by slow flow and stable development of the meandering process, and rapid-waterfall – located in the upper reaches of the channel. The latter is characterized by a stormy current and the presence of numerous rapids made of boulders and wood. There are 3 main morphodynamic types of the channel – meandering, branched, and straightforward, and 6 their subtypes. Meandering, incised channels are characterized by structural meanders, their shores are composed of hard rocks, mostly sandstones. The meandering confined channels are defined by the root bank in the apical part and the upper wing along the root bank, which leads to the formation of segmental and blockage convolutions. Meandering, broad-flooded channels are characterized by longitudinal displacement of meanders, their convolutions are segmented, rarely loop-shaped. The coefficient of meandering gradually increases from the mountainous part of the channel to the plain one (1.10–1.35). Branched type is represented by a single complex and floodplain-channel subtypes. The size of the islands that divide the channel into arms is from a few meters to 350–400 m. The straightforward type of channel is widespread and is 1/3 of the total length of the river. Key words: channel type; straightforward; branched; meandering; incised; confined; floodplain.


1966 ◽  
Vol 24 ◽  
pp. 21-23
Author(s):  
Y. Fujita

We have investigated the spectrograms (dispersion: 8Å/mm) in the photographic infrared region fromλ7500 toλ9000 of some carbon stars obtained by the coudé spectrograph of the 74-inch reflector attached to the Okayama Astrophysical Observatory. The names of the stars investigated are listed in Table 1.


Author(s):  
Gerald Fine ◽  
Azorides R. Morales

For years the separation of carcinoma and sarcoma and the subclassification of sarcomas has been based on the appearance of the tumor cells and their microscopic growth pattern and information derived from certain histochemical and special stains. Although this method of study has produced good agreement among pathologists in the separation of carcinoma from sarcoma, it has given less uniform results in the subclassification of sarcomas. There remain examples of neoplasms of different histogenesis, the classification of which is questionable because of similar cytologic and growth patterns at the light microscopic level; i.e. amelanotic melanoma versus carcinoma and occasionally sarcoma, sarcomas with an epithelial pattern of growth simulating carcinoma, histologically similar mesenchymal tumors of different histogenesis (histiocytoma versus rhabdomyosarcoma, lytic osteogenic sarcoma versus rhabdomyosarcoma), and myxomatous mesenchymal tumors of diverse histogenesis (myxoid rhabdo and liposarcomas, cardiac myxoma, myxoid neurofibroma, etc.)


Author(s):  
Irving Dardick

With the extensive industrial use of asbestos in this century and the long latent period (20-50 years) between exposure and tumor presentation, the incidence of malignant mesothelioma is now increasing. Thus, surgical pathologists are more frequently faced with the dilemma of differentiating mesothelioma from metastatic adenocarcinoma and spindle-cell sarcoma involving serosal surfaces. Electron microscopy is amodality useful in clarifying this problem.In utilizing ultrastructural features in the diagnosis of mesothelioma, it is essential to appreciate that the classification of this tumor reflects a variety of morphologic forms of differing biologic behavior (Table 1). Furthermore, with the variable histology and degree of differentiation in mesotheliomas it might be expected that the ultrastructure of such tumors also reflects a range of cytological features. Such is the case.


Author(s):  
Paul DeCosta ◽  
Kyugon Cho ◽  
Stephen Shemlon ◽  
Heesung Jun ◽  
Stanley M. Dunn

Introduction: The analysis and interpretation of electron micrographs of cells and tissues, often requires the accurate extraction of structural networks, which either provide immediate 2D or 3D information, or from which the desired information can be inferred. The images of these structures contain lines and/or curves whose orientation, lengths, and intersections characterize the overall network.Some examples exist of studies that have been done in the analysis of networks of natural structures. In, Sebok and Roemer determine the complexity of nerve structures in an EM formed slide. Here the number of nodes that exist in the image describes how dense nerve fibers are in a particular region of the skin. Hildith proposes a network structural analysis algorithm for the automatic classification of chromosome spreads (type, relative size and orientation).


Author(s):  
Jacob S. Hanker ◽  
Dale N. Holdren ◽  
Kenneth L. Cohen ◽  
Beverly L. Giammara

Keratitis and conjunctivitis (infections of the cornea or conjunctiva) are ocular infections caused by various bacteria, fungi, viruses or parasites; bacteria, however, are usually prominent. Systemic conditions such as alcoholism, diabetes, debilitating disease, AIDS and immunosuppressive therapy can lead to increased susceptibility but trauma and contact lens use are very important factors. Gram-negative bacteria are most frequently cultured in these situations and Pseudomonas aeruginosa is most usually isolated from culture-positive ulcers of patients using contact lenses. Smears for staining can be obtained with a special swab or spatula and Gram staining frequently guides choice of a therapeutic rinse prior to the report of the culture results upon which specific antibiotic therapy is based. In some cases staining of the direct smear may be diagnostic in situations where the culture will not grow. In these cases different types of stains occasionally assist in guiding therapy.


Author(s):  
S. Arumugam ◽  
Sarasa Bharati Arumugam

Adenoaas of the pituitary are no longer classified based on their tinctorial affinity to dyes. With the advent of the newer methods of sophisticated technology, it is now possible to classify. These depending upon the type of hormone secreted based either on histochemical techniques or on ultrastructural characteristics. The latter provides an insight into the cytoplasmic organelle morphology which offers a delightful feast to the eye as well.This paper presents the ultrastructural characters of the pituitary adenoma as seen in Madras. 171 adenomas (124 males and 47 females) were seen during 1972-1989, classified at the light microscope level as 159 chromophobe, 2 basophilic, 4 eosinophilic and 6 mixed adenomas.Ultrastructural examination showed that the sparsely granular prolactin cell adenoma is the commonest adenoma to be encountered closely followed by the growth hormone cell adenoma, null cell adenoma, the mixed cell adenoma and others.


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