Field Determination of Fracture Propagation Mode Using Downhole Pressure Data

2015 ◽  
Author(s):  
Ali Daneshy ◽  
Chad Touchet ◽  
Fred Hoffman ◽  
Mike McKown
Keyword(s):  
Propagation Mode ◽  
Fluid Migration ◽  
Pressure Data ◽  
Isolation System ◽  
Fracture Orientation ◽  
Coiled Tubing ◽  
Treatment Data ◽  
Set Up ◽  
Adjacent Fractures ◽  
First Time

Abstract This paper presents the analysis results of 60 single stage fracturing treatments performed in a horizontal well using cemented casing sleeves and a coiled tubing deployed frac isolation system as the completion method. In this carefully set-up and executed treatment, separation between the toe stages was 97 feet, and near the heel it was 55 feet. Pressure data was collected above and below the retrievable plug used for stage isolation. This data was used for analysis of fracturing treatment data which included mode of propagation, completion efficiency, and a rough estimate of fracture orientation. The analysis showed that; There was no interaction between adjacent fractures during five of the sixty fracturing stages. None of these was in the well interval with shorter fracture spacingFracture shadowing occurred during six fracture stages, again none in the shorter spacing intervalMinor cement defects (micro-annuli) caused some fluid migration into the passive segment of the well. This happened in 27 stages. Of these; In eleven cases the cement defects were plugged after a while, causing the migration of fracturing fluid into the passive interval to stop.In sixteen other cases the fluid migration through cement micro-annuli continued during fracturing.During ten stages, defective zone isolation and fluid migration caused a pressure increase of several hundred psi in the passive segment of the well. But this did not result in extension of passive fractures.The volume of migrated slurry due to inadequate zone isolation was mostly a very small fraction of the injected volume.During five stages poor cement quality hampered stage isolation and caused immediate link between adjacent active and passive intervals and extension of passive fractures.The data indicate possible connection between the active and one passive fracture in four stages.Shorter spacing between stages increased the incidents of fluid migration due to poor cement qualityThe fracturing pressure variations during the treatments did not indicate presence of large stress shadowingA rough estimation of fracture orientation indicates that they were likely to be vertical and nearly perpendicular to the wellbore.The fracture growth pattern can best be described as off-balance. To our knowledge, this is the first time existence of direct communication between adjacent fractures has been observed through actual pressure interference data.

Cobalt/Lewis Acid Catalysis for Hydrocarbofunctionalization of Alkynes via Cooperative C–H Activation

2020 ◽  
Author(s):  
Chang-Sheng Wang ◽  
Sabrina Monaco ◽  
Anh Ngoc Thai ◽  
Md. Shafiqur Rahman ◽  
Chen Wang ◽  
...  
Keyword(s):  
Catalytic System ◽  
Lewis Acid ◽  
Hydrogen Transfer ◽  
Acid Catalysis ◽  
Rate Limiting Step ◽  
Site Selectivity ◽  
Set Up ◽  
Site Selective ◽  
First Time ◽  
Rate Limiting

A catalytic system comprised of a cobalt-diphosphine complex and a Lewis acid (LA) such as AlMe3 has been found to promote hydrocarbofunctionalization reactions of alkynes with Lewis basic and electron-deficient substrates such as formamides, pyridones, pyridines, and azole derivatives through site-selective C-H activation. Compared with known Ni/LA catalytic system for analogous transformations, the present catalytic system not only feature convenient set up using inexpensive and bench-stable precatalyst and ligand such as Co(acac)3 and 1,3-bis(diphenylphosphino)propane (dppp), but also display distinct site-selectivity toward C-H activation of pyridone and pyridine derivatives. In particular, a completely C4-selective alkenylation of pyridine has been achieved for the first time. Mechanistic stidies including DFT calculations on the Co/Al-catalyzed addition of formamide to alkyne have suggested that the reaction involves cleavage of the carbamoyl C-H bond as the rate-limiting step, which proceeds through a ligand-to-ligand hydrogen transfer (LLHT) mechanism leading to an alkyl(carbamoyl)cobalt intermediate.

scholarly journals Stay at Home! Governance Quality and Effectiveness of Lockdown

2021 ◽  
Author(s):  
Vincenzo Alfano ◽  
Salvatore Ercolano
Keyword(s):  
Rule Of Law ◽  
Global Scale ◽  
Considerable Time ◽  
Government Effectiveness ◽  
Governance Indicators ◽  
Regulatory Quality ◽  
Governance Quality ◽  
World Governance Indicators ◽  
Set Up ◽  
First Time

AbstractIn order to control the spread of the COVID-19 pandemic, during the first wave of the pandemic numerous countries decided to adopt lockdown policies. It had been a considerable time since such measures were last introduced, and the first time that they were implemented on such a global scale in a contemporary, information intensive society. The effectiveness of such measures may depend on how citizens perceive the capacity of government to set up and implement sound policies. Indeed, lockdown and confinement policies in general are binding measures that people are not used to, and which raise serious concerns among the population. For this reason governance quality could affect the perception of the benefits related to the government’s choice to impose lockdown, making citizens more inclined to accept it and restrict their movements. In the present paper we empirically investigate the relation between the efficacy of lockdown and governance quality (measured through World Governance Indicators). Our results suggest that countries with higher levels of government effectiveness, rule of law and regulatory quality reach better results in adopting lockdown measures.

Excavations in the City of London: First Interim Report, 1974–1975

1977 ◽  
Vol 57 (1) ◽  
pp. 31-66 ◽  
Author(s):  
Brian Hobley ◽  
John Schofield ◽  
Tony Dyson ◽  
Peter R. V. Marsden ◽  
Charles Hill ◽  
...  
Keyword(s):  
Urban Archaeology ◽  
Interim Report ◽  
Set Up ◽  
City Of London ◽  
First Time ◽  
The City ◽  
Important Evidence

SummaryThe Department of Urban Archaeology, City of London, was set up in December 1973 as part of Guildhall Museum, now the Museum of London. Since then it has excavated sixteen sites and carried out numerous watching briefs. Most of the formal excavations have been conducted on the vital waterfront sites, made available for the first time, and on the Roman and medieval defences of the City. Important evidence of the elusive Saxon occupation is gradually coming to light, and the work is accompanied by specialist research, particularly finds, environmental and documentary.

scholarly journals Coriolis effects on the elliptical instability in cylindrical and spherical rotating containers

2007 ◽  
Vol 585 ◽  
pp. 323-342 ◽  
Author(s):  
M. LE BARS ◽  
S. LE DIZÈS ◽  
P. LE GAL
Keyword(s):  
Growth Rates ◽  
Close Agreement ◽  
Unstable Mode ◽  
Quantitative Agreement ◽  
Fixed Rate ◽  
Elliptical Instability ◽  
Normal Mode Theory ◽  
Set Up ◽  
First Time ◽  
Selection Of

The effects of the Coriolis force on the elliptical instability are studied experimentally in cylindrical and spherical rotating containers placed on a table rotating at a fixed rate $\tilde{\Omega}^G$. For a given set-up, changing the ratio ΩG of global rotation $\tilde{\Omega}^G$ to flow rotation $\tilde{\Omega}^F$ leads to the selection of various unstable modes due to the presence of resonance bands, in close agreement with the normal-mode theory. No instability occurs when ΩG varies between −3/2 and −1/2 typically. On decreasing ΩG toward −1/2, resonance bands are first discretized for ΩG<0 and progressively overlap for −1/2 ≪ ΩG < 0. Simultaneously, the growth rates and wavenumbers of the prevalent stationary unstable mode significantly increase, in quantitative agreement with the viscous short-wavelength analysis. New complex resonances have been observed for the first time for the sphere, in addition to the standard spin-over. We argue that these results have significant implications in geo- and astrophysical contexts.

scholarly journals A visual method based on Lewis dot electron structures (VISLEDS) for teaching inorganic formulation

2020 ◽  
Author(s):  
Abigail Jimenez
Keyword(s):  
Secondary School ◽  
Cognitive Load ◽  
Secondary School Students ◽  
Chemical Compounds ◽  
School Students ◽  
Visual Method ◽  
Set Up ◽  
Visual Description ◽  
First Time ◽  
Theory Framework

Chemistry is usually seen as a difficult subject for secondary school students. One topic they struggle is when they face chemistry formulation for the first time. The concept of oxidation number is difficult for them. The level of abstraction required is still developing in their minds. We must help them visualise it, to understand bonding and, finally, the symbolic representation of chemical compounds.We find in chemistry a visual description for bond formation: Lewis diagrams. They explicitly show molecular bonds as paired electrons. By using this simple idea, we can introduce formulation to secondary school students. Starting with binary chemical compounds, included in 3rd year of secondary schools in Spain, we can set up the foundations for their future chemistry studies. Of course, the difficulty must be progressively introduced.In this work, we show how a visual method based on Lewis diagrams improves the performance of students when writing formulae of binary chemical compounds. One important difference with current literature on how Lewis dot structures are used in education, is that, while they are usually presented as a learning goal, here we use them as a means to an end.Our results suggest that the improvement is higher for students with previous lower academic performance, low scores in linguistic competencies, and high scores in visual and artistic competencies. Most importantly, it does not worsen performance for students with high scores in linguistic competencies and low scores in visual and artistic competencies. Mathematical competencies do not seem to be so good predictors for students’ performance.Finally, within the Cognitive Load Theory framework, we show how cognitive working load, as well as an approximation of extraneous cognitive load, can be estimated by using information theory measures involving the mistakes students make.

scholarly journals Guidance Level for Brevetoxins in French Shellfish

Marine Drugs ◽  
2021 ◽  
Vol 19 (9) ◽  
pp. 520
Author(s):  
Nathalie Arnich ◽  
Eric Abadie ◽  
Zouher Amzil ◽  
Marie-Yasmine Dechraoui Bottein ◽  
Katia Comte ◽  
...  
Keyword(s):  
Working Group ◽  
Case Reports ◽  
Human Case ◽  
Portion Size ◽  
Shellfish Poisoning ◽  
Marine Biotoxins ◽  
Toxicological Data ◽  
Set Up ◽  
First Time ◽  
Environmental And Occupational Health

Brevetoxins (BTXs) are marine biotoxins responsible for neurotoxic shellfish poisoning (NSP) after ingestion of contaminated shellfish. NSP is characterized by neurological, gastrointestinal and/or cardiovascular symptoms. The main known producer of BTXs is the dinoflagellate Karenia brevis, but other microalgae are also suspected to synthesize BTX-like compounds. BTXs are currently not regulated in France and in Europe. In November 2018, they have been detected for the first time in France in mussels from a lagoon in the Corsica Island (Mediterranean Sea), as part of the network for monitoring the emergence of marine biotoxins in shellfish. To prevent health risks associated with the consumption of shellfish contaminated with BTXs in France, a working group was set up by the French Agency for Food, Environmental and Occupational Health & Safety (Anses). One of the aims of this working group was to propose a guidance level for the presence of BTXs in shellfish. Toxicological data were too limited to derive an acute oral reference dose (ARfD). Based on human case reports, we identified two lowest-observed-adverse-effect levels (LOAELs). A guidance level of 180 µg BTX-3 eq./kg shellfish meat is proposed, considering a protective default portion size of 400 g shellfish meat.

Printers to Hendrik Niclaes: Plantin and Augustijn van Hasselt

Quaerendo ◽  
1984 ◽  
Vol 14 (4) ◽  
pp. 247-272 ◽  
Author(s):  
Paul Valkema Blouw
Keyword(s):  
The Other ◽  
Literary Sources ◽  
The Family ◽  
Religious Sect ◽  
Set Up ◽  
Number Of Publications ◽  
First Time ◽  
New Evidence ◽  
Publishing Business

AbstractFrom the chronicles of the Family of Love we know that, besides printers in Deventer and later in Cologne, both Plantin and Augustijn van Hasselt printed for this religious sect. On the basis of this information quite a large number of publications have hitherto been attributed to Plantin, while only one single edition in Latin was reckoned to be the work of Augustijn. An analysis of the typography, however, shows that apart from Hendrik Niclaes's chief work, Den Spegel der Gherechticheyt, Plantin only printed two of his minor writings and that all the other ascriptions to Plantin must be revised in favour of Augustijn van Hasselt. In 1561-2 Augustijn was running a printing shop in the Dutch town of Kampen, specially set up by HN for the purpose of publishing those of his works that had not previously been printed. Plantin, who was partly involved in this enterprise, took the opportunity to have a book printed on this press for his publishing business. The analysis providing the typographical evidence of this collaboration proves for the first time the accuracy of the literary sources as regards Plantin's involvement in the publication of the works of Hendrik Niclaes. In the presentation of the new evidence it was necessary to establish more clearly the date of Plantin's '[1561]' inventory and which roman and German types he owned at what times. The article ends with some notes regarding the end of the 'Bohmbargen' press at Cologne.

First Multistage Hydraulic Fracturing in Russian Offshore: Integrated Approach to Completion and Stimulation of Apt Deposits of V.Filanovsky Field

2021 ◽  
Author(s):  
Mikhail Yurievich Golenkin ◽  
Denis Vladimirovich Eliseev ◽  
Alexander Anatolyevich Zemchikhin ◽  
Alexey Alexandrovich Borisenko ◽  
Akhmat Sakhadinovich Atabiyev ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Caspian Sea ◽  
Complex Type ◽  
The Caspian Sea ◽  
Multistage Hydraulic Fracturing ◽  
Coiled Tubing ◽  
Sand Control ◽  
Friction Reducing ◽  
First Time ◽  
Stimulation Of

Abstract The paper describes the results of the first multistage hydraulic fracturing operations in Russia on the Caspian Sea shelf in the gas condensate and oil deposits of the Aptian formation of V. Filanovsky field. In addition to the small productive formation depth, long horizontal sections with a complex trajectory and high collapse gradients due to large zenith angles when passing the Albian and Aptian deposits of poorly consolidated sandstones are an additional challenge for choosing a multistage hydraulic fracturing assembly. The above features require the use of modern sand control screens with enhanced frac sleeves. A design was developed which includes frac sleeves and sand control screens that can withstand multiple cycles of hydraulic impact during hydraulic fracturing, as well as many opening/closing cycles. A seawater-based frac fluid system was applied. The frac fleet was located on a pontoon, the coiled tubing – on a platform. For the first time in Russia, a 2-5/8 inch coiled tubing with a complex-type friction reducing system was used to switch coupling/sleeves in conditions of very long horizontal sections, complex trajectories, and high friction coefficients. The minimum distances between the screen's sliding sleeves and frac sleeves did not prevent from performing manipulations in complex environment. For well cleaning, the frac assemblies of reverse rotary-pulse and rotary-directional types were used. At the first stage of the project, the development of an optimal method of well completion was successfully implemented. Due to the close interaction of the operating company, service company, and science & engineering team of the operator, for the first time in Russia the design of downhole equipment with the use of advanced technologies of sand control screens, frac sleeves was presented. This solution has proved its effectiveness – the downhole equipment has retained its operational properties after a long period of well operation and further in the process of hydraulic fracturing. At the second stage of the project, 32 MSHF operations were performed at four wells. To reduce nonproductive time and operational risks, a satellite communication complex was additionally deployed on the pontoon to join the engineering centers of Astrakhan, Moscow, and Houston. After finishing the well development, the design indicators for formation fluid rates were achieved, which proved the effectiveness of the stimulation of the field's target objects – this opens great prospects for further development of low-permeability reservoirs at offshore sites in the Caspian Sea. The successful project implementation and the achievement of the design values of oil flow rates has expanded the possibilities of commercial operation of the low-permeable Aptian formation, complicated by the presence of a gas cap and underlying water. A solution was presented for working in extended horizontal well sections with 2-5/8 inch coiled tubing together with a complex-type mechanical friction reducing system. The economic effect was achieved when solving tasks of manipulating mechanical screen couplings and frac port sleeves without the involvement of downhole tractors. The use of new solutions in the completion assembly made it possible to eliminate additional sand ingress problems.

American Soldiers and Okinawan Women

2017 ◽  
Author(s):  
Etsuko Takushi Crissey
Keyword(s):  
Vietnam War ◽  
Biracial Children ◽  
Civilian Leaders ◽  
Women And Children ◽  
Intimate Relations ◽  
Set Up ◽  
The Many ◽  
The Right ◽  
First Time ◽  
The U.S

In September, 1945, with most Okinawans still in refugee camps, the U.S. military ordered elections for civilian leaders in which women were granted the right to vote for the first time, seven months earlier than in mainland Japan. Yet they were far more concerned about the many rapes committed by American soldiers. Women and girls were abducted from fields while searching for food, dragged away from their homes, and assaulted in front of their families. After months of inaction, the U.S. military decided to set up “special amusement areas” for prostitution in certain towns. Some Okinawans favoured this policy as a “breakwater” to protect women and children of “good” families, while others opposed it as exploitation of women. In 1967, at the peak of the Vietnam War, an estimated 10,000 women engaged in prostitution. In 1948 the U.S. military rescinded a ban on marriages between U.S. soldiers and Okinawan women that failed to prevent couples from having intimate relations and living together. Still, commanding officers pressured soldiers not to marry, threatening disciplinary transfers. By 1967, among thousands of biracial children in Okinawa, about half were raised by mothers or their relatives with little or no financial support from fathers.

Mr Newman’s Section

Colossus ◽  
2006 ◽  
Author(s):  
Jack Copeland ◽  
Catherine Caughey
Keyword(s):  
Indicator System ◽  
Think Tank ◽  
Separate Section ◽  
Research Section ◽  
Other Hand ◽  
Set Up ◽  
First Time

When Turing arrived at Bletchley Park, the day after Chamberlain’s announcement of war with Germany, he joined Dilly Knox’s Research Section. The job of the Research Section was to study enemy ciphers and operating procedures, and to devise methods of attack. The techniques invented by this high-powered think-tank were then handed over to other sections where they were used operationally against the enemy traffic. In 1939, Enigma was the focus of research. By the time Tutte joined the Research Section, in mid-1941, Captain Gerry Morgan headed it. Tunny soon became the leading problem. Thanks to Tutte, the Research Section broke the Tunny machine in January 1942, and in July read up-to-date traffic for the first time. Tunny could now be tackled operationally, and a Tunny-breaking section was immediately set up under Major Ralph Tester. Several members of the Research Section moved over to the ‘Testery’. Armed with Turingery and other hand methods, the Testery read nearly every message from July to October 1942—thanks to the insecure 12-letter indicator system (see Chapter 3). In October, however, the 12-letter indicators were replaced by QEP numbers and the Testery, now completely reliant on depths, fell on leaner times (see Chapter 5). The Research Section renewed its efforts against Tunny, looking for a means of wheel setting that did not depend on depths. With the invention of Tutte’s method, Newman was given the job of developing the necessary machinery, and when the Heath Robinson was delivered in June 1943 the ‘Newmanry’ became a separate section. From December 1943 the Newmanry would be responsible for breaking and setting the chi-wheels, and the Testery for breaking and setting the remaining wheels manually. The two sections worked hand-in-glove. Initially Newman’s staff consisted of one cryptographer (Michie), two engineers, and 16 Wrens. Soon a second cryptographer arrived (Good), and after three months of experimentation, two or three messages were being set each week. ‘Cryptographers’, ‘engineers’, and ‘Wrens’ remained the principal staffing categories of the Newmanry throughout the war. By May 1945, there were 26 cryptographers, 28 engineers, and 273 Wrens. During the period June 1943 to July 1944, two Americans joined the cryptographic staff of the Newmanry.

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