Directional orientations of solitary rugose corals

1987 ◽  
Vol 24 (4) ◽  
pp. 806-812 ◽  
Author(s):  
Robert J. Elias ◽  
Robert J. McAuley ◽  
Blair W. Mattison
Keyword(s):  
Flow Direction ◽  
Significant Degree ◽  
Upper Ordovician ◽  
Water Motion ◽  
Lower Silurian ◽  
Rugose Corals ◽  
Flow Directions ◽  
Directional Distributions ◽  
Geologic Record

Unattached solitary rugose corals lying parallel to bedding are common in many Ordovician and younger Paleozoic units, but their directional orientations have seldom been examined. Interpretations based on occurrences in North American Upper Ordovician and Lower Silurian strata provide a foundation for such studies. Distinct directional patterns resulted from preferred orientation with respect to water motion. They indicate transportation rather than biologic orientation, if it can be shown that the corals were not preserved in life position or were abraded to a significant degree before burial. Transported, slightly curved specimens having trochoid to ceratoid form were aligned parallel to currents, with the apex pointing upstream, and (or) were rolled nearly perpendicular to currents or almost parallel to crests of advancing waves, with the apex facing either way but directed slightly upstream. Therefore, unimodal orientation patterns, bimodal patterns with equal peaks that are opposite one another but slightly skewed, and trimodal patterns that are a combination of these can be used to determine flow directions. An apparently bimodal pattern with nearly equal and directly opposite peaks has been observed in a case involving mostly subcalceoloid corals. These individuals may have been aligned parallel to currents or to the direction of wave progression, with the apex facing either way. Random directional distributions do not necessarily indicate low-energy environments. They could have resulted from changes in flow direction during the time in which the sampled stratigraphic interval was deposited or from the effects of bioturbation on corals that were initially preferentially oriented.Directional patterns of solitary rugose corals are of value in paleoecology (recognition of transported assemblages) and basin analysis (determination of paleocurrent directions). They may also prove to be useful in making paleoenvironmental reconstructions (type of water motion, nature of substrate) if the reasons for different types of orientation patterns can be established with experimental work and additional data from the geologic record.

Direct Determination of Groundwater Direction and Velocity Using Colloidal Borescope at Jenderam Hilir, Selangor

2015 ◽  
Vol 802 ◽  
pp. 640-645 ◽  
Author(s):  
Miskiah Fadzilah binti Ghazali ◽  
Mohd Nordin bin Adlan ◽  
Kamarudin bin Samuding ◽  
Mohamad Razip bin Selamat
Keyword(s):  
Groundwater Flow ◽  
Colloidal Particles ◽  
Flow Direction ◽  
Direct Determination ◽  
Pumping Test ◽  
Flow Speed ◽  
Monitoring Well ◽  
Flux Gate ◽  
Flow Directions

The colloidal borescope can be used for measuring groundwater flow directions and velocity. It is an integrated high-resolution flux gate compass with a high-magnification colloid-imaging camera that can measure flow at selected depths within a well. In this study, the colloidal borescope was used to determine flow direction and measure velocity during a pumping test for the riverbank filtration study in Jenderam Hilir, Selangor. During each measurement, the instrument, which monitored the movement of the suspended particles, was inserted into a well at a particular depth (screen well). The relative flow direction was determined by plotting the trajectory and speed of colloidal particles across the screen with AquaLITE Software, which determined the horizontal speed of the particles and flow speed. The groundwater flow pattern was dtermined at four boreholes in the study area, and the groundwater flow velocities were found ranging from 0.72 to 2.45 x (10-4) m/s. The direction of the groundwater flow at boreholes monitoring well 02 (MW02) and monitoring well 19 (MW19) was moved toward borehole pumping well (PW). The groundwater flow at monitoring well 01 (MW01) was moving toward the northwest of the study site which was parallel with the Langat river. The groundwater flow in borehole monitoring well A (MWA) was toward the southern part of the study site and was not affected by the pumping test activities at borehole monitoring well 03 (MW03).

scholarly journals Difference Analysis of Organic Matter Enrichment Mechanisms in Upper Ordovician-Lower Silurian Shale from the Yangtze Region of Southern China and Its Geological Significance in Shale Gas Exploration

Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Ming Wen ◽  
Zhenxue Jiang ◽  
Kun Zhang ◽  
Yan Song ◽  
Shu Jiang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Shale Gas ◽  
Southern China ◽  
Sedimentary Organic Matter ◽  
Gas Content ◽  
Silicon Isotope ◽  
Upper Ordovician ◽  
Lower Silurian ◽  
Excess Silicon ◽  
Lower Yangtze

The upper Ordovician-lower Silurian shale has always been the main target of marine shale gas exploration in southern China. However, the shale gas content varies greatly across different regions. The organic matter content is one of the most important factors in determining gas content; therefore, determining the enrichment mechanisms of organic matter is an important problem that needs to be solved urgently. In this paper, upper Ordovician-lower Silurian shale samples from the X-1 and Y-1 wells that are located in the southern Sichuan area of the upper Yangtze region and the northwestern Jiangxi area of the lower Yangtze region, respectively, are selected for analysis. Based on the core sample description, well logging data analysis, mineral and elemental composition analysis, silicon isotope analysis, and TOC (total organic carbon) content analysis, the upper Ordovician-lower Silurian shale is studied to quantitatively calculate its content of excess silicon. Subsequently, the results of elemental analysis and silicon isotope analysis are used to determine the origin of excess silicon. Finally, we used U/Th to determine the characteristics of the redox environment and the relationship between excess barium and TOC content to judge paleoproductivity and further studied the mechanism underlying sedimentary organic matter enrichment in the study area. The results show that the excess silicon from the upper Ordovician-lower Silurian shale in the upper Yangtze area is derived from biogenesis. The sedimentary water body is divided into an oxygen-rich upper water layer that has higher paleoproductivity and a strongly reducing lower water that is conducive to the preservation of sedimentary organic matter. Thus, for the upper Ordovician-lower Silurian shale in the upper Yangtze region, exploration should be conducted in the center of the blocks with high TOC contents and strongly reducing water body. However, the excess silicon in the upper Ordovician-lower Silurian shale of the lower Yangtze area originates from hydrothermal activity that can enhance the reducibility of the bottom water and carry nutrients from the crust to improve paleoproductivity and enrich sedimentary organic matter. Therefore, for the upper Ordovician-lower Silurian shale in the lower Yangtze region, exploration should be conducted in the blocks near the junction of the two plates where hydrothermal activity was active.

scholarly journals Effect of Hydrothermal Activity on Organic Matter Enrichment of Shale: A Case Study of the Upper Ordovician and the Lower Silurian in the Lower Yangtze, South China

Minerals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 495 ◽  
Author(s):  
Yizhou Huang ◽  
Zhenxue Jiang ◽  
Kun Zhang ◽  
Yan Song ◽  
Shu Jiang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Oxygen Isotope ◽  
Shale Gas ◽  
Organic Matter Content ◽  
Hydrothermal Activity ◽  
Late Ordovician ◽  
Sedimentary Organic Matter ◽  
Upper Ordovician ◽  
Lower Silurian ◽  
Activity Intensity

The effect of organic matter on hydrocarbon potential, storage space, and gas content of shale is well-known. Additionally, present-day content of sedimentary organic matter in shale is controlled by depositional and preservation processes. Therefore, a study of the enrichment mechanisms of sedimentary organic matter provides a scientific basis for the determination of favorable areas of shale gas. In this study the Upper Ordovician Xinkailing Fm. and the first member of the Lower Silurian Lishuwo Fm. were examined. Stratigraphic sequences were identified through conventional logs and elemental capture spectrum data. Oxygen isotope analysis was applied to recover paleotemperature of seawater in the study area. The excess silicon content was calculated and the origin of the silica was determined by the Fe-Al-Mn ternary plot. The enrichment mechanism of organic matter was analyzed by two aspects: redox conditions and paleoproductivity. As a result, the stratigraphic interval was divided into two 3rd-order sequences. Through oxygen isotope, the paleotemperature of seawater was 62.7–79.2 °C, providing evidence of the development of hydrothermal activity. Analysis of excess siliceous minerals identified two siliceous mineral origins: terrigenous and hydrothermal. It also revealed an upwards decreasing tendency in hydrothermal activity intensity. Strong hydrothermal activity during the Late Ordovician, recognized as TST1, formed a weak-oxidizing to poor-oxygen environment with high paleoproductivity, which promoted organic matter enrichment. During the Late Ordovician to the Early Silurian, identified as RST1, TST2, and RST2, weakening hydrothermal activity caused the decline of paleoproductivity and increased oxidation of bottom waters, leading to a relative decrease of organic matter content in the shale. Therefore, favorable areas of shale gas accumulation in the Upper Ordovician and Lower Silurian are determined stratigraphically as the TST1, with a high total organic carbonate content. Geographically, the hydrothermally-active area near the plate connection of the Yangtze and the Cathaysian is most favorable.

scholarly journals A murine model of elastase- and cigarette smoke-induced emphysema

2017 ◽  
Vol 43 (2) ◽  
pp. 95-100 ◽  
Author(s):  
Rubia Rodrigues ◽  
Clarice Rosa Olivo ◽  
Juliana Dias Lourenço ◽  
Alyne Riane ◽  
Daniela Aparecida de Brito Cervilha ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Murine Model ◽  
Respiratory Mechanics ◽  
Lung Parenchyma ◽  
Time Frame ◽  
Significant Degree ◽  
Mean Linear Intercept ◽  
Distal Lung ◽  
Intranasal Instillation

ABSTRACT Objective: To describe a murine model of emphysema induced by a combination of exposure to cigarette smoke (CS) and instillation of porcine pancreatic elastase (PPE). Methods: A total of 38 C57BL/6 mice were randomly divided into four groups: control (one intranasal instillation of 0.9% saline solution); PPE (two intranasal instillations of PPE); CS (CS exposure for 60 days); and CS + PPE (two intranasal instillations of PPE + CS exposure for 60 days). At the end of the experimental protocol, all animals were anesthetized and tracheostomized for calculation of respiratory mechanics parameters. Subsequently, all animals were euthanized and their lungs were removed for measurement of the mean linear intercept (Lm) and determination of the numbers of cells that were immunoreactive to macrophage (MAC)-2 antigen, matrix metalloproteinase (MMP)-12, and glycosylated 91-kDa glycoprotein (gp91phox) in the distal lung parenchyma and peribronchial region. Results: Although there were no differences among the four groups regarding the respiratory mechanics parameters assessed, there was an increase in the Lm in the CS + PPE group. The numbers of MAC-2-positive cells in the peribronchial region and distal lung parenchyma were higher in the CS + PPE group than in the other groups, as were the numbers of cells that were positive for MMP-12 and gp91phox, although only in the distal lung parenchyma. Conclusions: Our model of emphysema induced by a combination of PPE instillation and CS exposure results in a significant degree of parenchymal destruction in a shorter time frame than that employed in other models of CS-induced emphysema, reinforcing the importance of protease-antiprotease imbalance and oxidant-antioxidant imbalance in the pathogenesis of emphysema.

Development And Testing Of Combined germicidal Recirculator

2021 ◽  
pp. 43-49
Author(s):  
Igor M. Dovlatov ◽  
Leonid Yu. Yuferev ◽  
Svetlana A. Mikaeva ◽  
Angela S. Mikaeva ◽  
Olga E. Zheleznikova
Keyword(s):  
Exposure Time ◽  
Flow Direction ◽  
Air Flow ◽  
Live Weight ◽  
Experimental Comparison ◽  
Disinfection Methods ◽  
Flow Parameters ◽  
Poultry Facilities ◽  
Air Disinfection

The important problem of the poultry farming is the prevention of infectious diseases causing poultry deaths and unplanned financial losses. The article authors represent an overview of the air disinfection methods and the selection criteria for the disinfection methods being the most effective among other methods applicable for poultry facilities. There were determined the main factors influencing the germicidal efficiency of the ultraviolet (UV) irradiance sources. Studies were considered, where influence on the germicidal efficiency was discussed in terms of the UV irradiation exposure time in poultry facilities with floor conditions. The theoretical parameters substantiation is given for the device combining the two main disinfection components; it is done by development of both the mathematical model for the average irradiance rate calculation and the calculation method of the highspeed air flow parameters. Also, the method has been developed for determination of the needed number of the combined germicidal aerosol units in poultry keeping premises. The authors present the results of the experiments conducted for determination of the germicidal efficiency of the disinfection fulfilled against such microorganisms as Coli bacteria, Kochii bacilli, etc. with use of the developed combined recirculator. The experimental comparison with a prototype was carried out for the decontamination efficiency achieved with aid of the newly developed combined germicidal aerosol recirculator used in the following mode: the exposure time made 1 hour of work, then 2 hours of break on condition of the process cycling throughout the entire daylight hours. Here presented is the recommended layout of a number of the combined germicidal aerosol units in box-type rooms with poultry keeping on floor in a case of the ideal air flow direction. The increase by 20 % was found in the disinfection efficiency as well as the growth by 7 % in the additional live weight gain of the poultry.

Foxe Platform and Basin Tectono-Sedimentary Element

2021 ◽  
pp. M57-2016-27
Author(s):  
Denis Lavoie ◽  
Nicolas Pinet ◽  
Shunxin Zhang
Keyword(s):  
Black Shales ◽  
Coarse Grained ◽  
Hudson Bay ◽  
Precambrian Basement ◽  
Upper Ordovician ◽  
Lower Paleozoic ◽  
Lower Silurian ◽  
The North ◽  
Marine Carbonate ◽  
Single Well

AbstractThe Foxe Platform and Basin Tectono-Sedimentary Element is an ovoid-shaped, predominantly marine basin located in the Canadian Arctic. The Paleozoic sedimentary succession (Cambrian to Silurian) unconformably overlies the Precambrian basement and reaches a maximum measured thickness of slightly over 500 metres in the only exploration well drilled in this basin. The Lower Paleozoic Foxe Platform and Basin Tectono-Sedimentary Element is surrounded by Precambrian basement and by the Paleozoic Arctic Platform to the north and by the Paleozoic-Mesozoic (?) Hudson Bay Strait Platform and Basin to the south. The Paleozoic succession consists of a Cambrian clastic-dominated interval overlain by Ordovician to lower Silurian predominantly shallow marine carbonate. Other than a single well drilled in the northern part of the basin, no subsurface information is available. Thermally immature Upper Ordovician organic matter rich calcareous black shales have been mapped on the onshore extension of the basin to the southeast. Potential hydrocarbon reservoirs consist of Cambrian porous coarse-grained clastics as well as Upper Ordovician dolostones and reefs.

scholarly journals The Role of Deep Geofluids in the Enrichment of Sedimentary Organic Matter: A Case Study of the Late Ordovician-Early Silurian in the Upper Yangtze Region and Early Cambrian in the Lower Yangtze Region, South China

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Kun Zhang ◽  
Jun Peng ◽  
Weiwei Liu ◽  
Bin Li ◽  
Qingsong Xia ◽  
...  
Keyword(s):  
Organic Matter ◽  
Water Surface ◽  
Sedimentary Organic Matter ◽  
Biological Productivity ◽  
Upper Ordovician ◽  
Longmaxi Formation ◽  
Lower Silurian ◽  
Lower Yangtze Region ◽  
Lower Yangtze ◽  
Volcanic Activities

Organic matter is the material basis for shales to generate hydrocarbon, as well as the main reservoir space and seepage channel for shale gas. When the thermal evolution degree is consistent, the organic carbon content in present shales is subject to the abundance of primitive sedimentary organic matter. Deep geofluids significantly influence the sedimentary organic matter’s enrichment, but the mechanism remains unclear. This paper is aimed at determining how hydrothermal and volcanic activities affected the enrichment of sedimentary organic matter by studying lower Cambrian shales in the lower Yangtze region and upper Ordovician-lower Silurian shales. Oxidation-reduction and biological productivity are used as indicators in the study. The result shows that hydrothermal or volcanic activities affected the enrichment of sedimentary organic matter by influencing climate changes and the nutrients’ sources on the waterbody’s surface and reducing water at the bottom. In the lower Cambrian shales of the Wangyinpu Formation in the lower Yangtze region, hydrothermal origin caused excess silicon. During the sedimentary period of the lower and middle-upper Wangyinpu Formation, vigorous hydrothermal activities increased the biological productivity on the waterbody’s surface and intensified the reducibility at the bottom of the waterbody, which enabled the rich sedimentary organic matter to be well preserved. During the sedimentary period of the lower upper Ordovician Wufeng Formation and the lower Silurian Longmaxi Formation in the upper Yangtze region, frequent volcanic activities caused high biological productivity on the waterbody surface and strong reducibility at the bottom of the waterbody. As a result, the abundant organic matter deposited from the water surface can be well preserved. During the sedimentary period of the upper Longmaxi Formation, volcanic activities died down gradually then disappeared, causing the biological productivity on the water surface to decrease. Besides, the small amount of organic matter deposited from the water surface was destroyed due to oxidation.

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