Petrophysics Essay Example for Free

Petrophysics Essay Abstract The South Tapti gas field, located in the Arabian Sea off the western coast of India, has been on production for the last three years. Drill Stem Tests (DST) conducted in five zones in the first appraisal well showed high sand production in all the tests at drawdowns as low as 20 psi. Due to the unconsolidated nature of the reservoir sand, it was decided to gravel pack all future wells. Initially, the High Rate Water Pack (HRWP) technique was used on 13 completions including some stack and selective completions. Due to a change in the drilling fluid to an oil based mud (OBM) system and the higher damage associated with the it, it was later decided to switch the gravel packing technique to ‘Frac and Pack’. This involved creation of a small frac to bypass the near wellbore damage using a gel-based fluid, followed by gravel placement using the HRWP. The Frac Pack technique was tried on 10 completions. Extensive production and pressure data collected on the above completions show that the ‘Frac Pack’ technique has led to a decrease in the mechanical skin by almost 70 %. More importantly, it has also been responsible for decreasing the Rate Dependent Skin Coefficient, D, by 50 %, which has a greater impact on the well productivity since these wells are produced at average rates of 25 MMSCFD. This paper describes the gravel packing techniques used in the South Tapti gas field, their evolution and the results achieved. Inroduction The South Tapti field, located off the Western coast of India, is represented by a series of alternating sand and shale sequences. The upper reservoir intervals are dominated by tidal-bar and channel sands deposited in a deltaic environment while the lower sands represent incised valley deposits consisting largely of alluvial/fluvial channels, tidal bars and tidal creeks. The exploratory wells drilled in the field indicated strong sand production tendencies due to the unconsolidated nature of the reservoir rock. This was corroborated by extensive testing of the first development well when all the five zones tested produced sand even under extremely low pressure drawdown conditions. The completion policy for the field focused on preventing sand ingress while minimizing the near well-bore damage inherent in any sand control application. The early development wells were gravel packed using the high rate water pack (HRWP) technique. These initial completions were highly successful in preventing sand production but also induced significant damage in the process. The problem was accentuated when the drilling mud system was changed to an oil base system in an attempt to offset recurrent drilling problems arising out of unconsolidated sandstone and presence of reactive clays. This called for a change in completion philosophy in order to ensure that the wells retain high productivity with effective sand control. Geologic and Reservoir Characterization The South Tapti field is localized by a broad SW-NE trending, doubly plunging anticline. The field has up to 13 different Oligo-Miocene gas bearing sands, separated by shales. The reservoir sands were deposited in both incised valley and deltaic settings. Reservoir sands within incised valleys consist of alluvial/fluvial channels, tide-influenced channels and tidal bars. The channel sands typically are the cleaner sands with excellent porosity permeability and up to 20 m thick, whereas the tide-influenced channels and tidal bars are shalier, with more modest porosity and permeability. CLAY MINERALS 1. Abstract: Tapti Basin in Surat Depression, Bombay Offshore is characterized by entirely siliciclastic succession. The cores and cutting samples, and wireline logs provide important information about the stratigraphy, basin fill, mineralogy, source and reservoir rock characteristics. Well under study is located in South Tapti sub-basin and contains gas-bearing sandstone within Mahim Formation of Late Oligocene age. The cuttings and cores have been megascopically examined and with the aid of electrical log data, the litholog of the well is prepared. The study involves XRD and major element analysis of selected samples. The XRD and digital log data from Natural Gamma Sepctrometry (NGS) log indicate that montmorillonite is the major clay mineral present in the upper part of the succession, whereas kaolinite present in the lower part (1868 m MD to 2427 m MD). Kaolinite is apparently formed by early stages of burial diagenesis, whereas montmorillonite is a weathering product of the Deccan Basalt. Interpretative lithology from the well log response shows that reservoir sandstones have developed within the depth interval of 1865m TVD to 1945 m TVD within dominantly shale lithology. Reservoir sandstones are semiconsolidated, medium to coarse grained and moderately well sorted. Quartz is the dominant detrital component in all the sandstones. Pay sands are quartz arenite whereas non-pay sands are quartz wacke with varying amount of clay matrix. Kaolinite in the reservoir section reduces the permeability of quartz wacke, but enhancing porosity in microlevel. Carbonate, siderite and iron oxide are main cementing material. Major element data showing that clastic sediments were delivered to the basin possibly by the Proto Tapti river but they may be having dual source of origin. The discriminant functions of Meyer and Nederlof, 1984 has indicated that the studied formations do not have source rock potential. Key words: Tapti Basin, Bombay Offshore, hydrocarbons, provenance and clay minerals. quartz wacke, but enhancing porosity in microlevel. Carbonate, siderite and iron oxide are main cementing material. Major element data showing that clastic sediments were delivered to the basin possibly by the Proto Tapti river but they may be having dual source of origin. The discriminant functions of Meyer and Nederlof, 1984 has indicated that the studied formations do not have source rock potential.

death penalty :: essays research papers

When turning on the television, radio, or simply opening the local newspaper, one is bombarded with news of arrests, murders, homicides, and other such tragedies. There are many things that I don't agree with in today's society but, out of all the wrongdoing that takes place, I believe murder including the death penalty is the worst of them. I am strongly against the death penalty because it violates God's rules, costs the tax payers too much money, the possible "wrongly accused," and it is cruel and unusual punishment. How often do these concepts creep into the public's mind when it hears of our `fair, trusty' government taking away someone's breathing rights? I do not support having the death penalty because it violates religious beliefs. Many religions, such as my own, Catholicism, follow the rules that God sent to use through the Ten Commandments. One of the most important of those ten states, "Thou shall not kill." If you are executing an individual, that clearly violates this commandment. Murdering any person, no matter what the individual has been convicted of, is a mortal sin. Therefore, God will punish anyone who aids in executing people. I believe that religious beliefs, such as the Ten Commandments, are the corner stone for our law system. Executing someone should not be made an exception to God's rule. My next reason against the death penalty is that taxpayers waste too much of their money with the death penalty. The average death penalty case is appealed three times. This means that the taxpayers must pay for the same trial to be heard three times. This is a very expensive practice. Also, the average convicted murder spends 12 years on death row. If supporters of the death penalty are positive enough to kill the person for committing the crime, shouldn't the supporters be confident enough to execute them in a timely manner? Why spend the taxpayer's money keeping these inmates in jail for so long? Taxpayer's money should go to better society, not to accommodate the prisoners that are going to end up dead. There's always the chance of the innocent being in the wrong place at the wrong time.

Written Analysis Final Project

Getting along with same sex marriage by EYE written Analysts Ms. Bawd I have read a few articles. I have had many discussions with some of the very conservative religious students I work with. I have been trying to figure out if the main front of the opposition to same sex marriage has a logical argument or if it is just a knocker reaction because religious conservatives think everyone that participate or even allows it is going to hell. I had the chance to interview Mr.. James, a student of a local Baptist college on his viewpoint of the subject.He indicates he eels that it is a sin and against Gods will, but that God gave man free will and he can choose his own fate. And, while he feels the need to try to help and educate homosexuals, if they disagree with those ideas, forcing the issue will only drive them further away. In his words, â€Å"forcing the Bible down someone's' throat is no way to build a flock†. The impacted population of the opposition to same sex marriage is all of the gays and lesbians of our country, studies estimate around 3. % or roughly 9 million people. Monsoons) Studies suggest lower general health among same sex peoples, one theory is this is due to one partner who has health insurance from their employer that cannot cover the other because they are not married and therefore not legally related. (Miller) Why we have this issue is because many people, notably Christians, feel that homosexuality is a conscious decision rather than an emotional attraction, because God said it was a sin.Leviticus 20:13, states, â€Å"If a man also lie with mankind, as he elite with a woman, both of them have committed an abomination: they shall surely be put to death† (KAVA). This was reaffirmed by the Pope, leader of the arrest group of Christians, who ironically dresses like Liberace stunt double. The problem here is 79. 5% of the U. S. Is Christian. Or close to 247 million people. (Fairchild) This seriously outnumbers the numbers of homose xuals looking to marry. Some feel it as a personal attack on their beliefs; others feel the need to save the homosexuals from the impending doom of eternity in hell.Although they are probably taking things out of context, I feel the bible was written to speak to the people of the day, and customs were different; there was less understanding of the perversity of the world then. Conservative folks back off the legal tactics. Laws that target only one group are unconstitutional. Former President Bill Clinton recently made a statement, â€Å"When I signed the bill, I included a statement with the admonition that ‘enactment of this legislation should not, despite the fierce and at times divisive rhetoric surrounding it, be understood to provide an excuse for discrimination. Reading those words today, I know now that, even worse than providing an excuse for discrimination, the law is itself discriminatory. It should be overturned. (Weber) Our First Amendment protections on the free dom of speech and religion, apply to all. By all means speak your minds, tell others how you feel about the issue. This is what is so great about this country, you can do that. Realize though, that same law that gives you the right to speak your mind, also give others the right to not listen. Please, the same law that protects you also protects everyone else.While you have the right to speak your mind, most will agree your rights stop at interfering with others' rights. Christian conservatives, you are so intent on having our way, but the more you push your views upon everyone the more you push them away! Remember Mr.. James, the Baptist student ministers' statement about forcing the Bible down someone's throat is no way to gather a flock. Yes, convey your ideals, but you cannot educate someone if they do not want to listen. And, offending them is a good way to close their ears and minds.In the argument about everyone's rights there was a compromise offered of a â€Å"civil unionâ € . This gave same sex couples some of the rights they were looking for, becoming a family making health insurance extendable to the partner, child custody between partners, survivorship of property in the event of one partner's death. This was not upheld at the federal level, only a handful of states accommodated. Somehow this was not enough; you had to have â€Å"marriage† and not a â€Å"civil union†. (GLAD) Same but separate somehow. It is not so much the word as it is the idea.I was hung up on why â€Å"marriage† was so important; the civil unions were on the right track. But if you were to say to me that Which was not a real religion, I would very likely go off on the discrimination of conservatives. Like many things, though, it takes time. The Thirteenth Amendment was ratified December 1865 to abolish slavery. There are still pockets of racists who would chain up blacks if they could. â€Å"Only' two years ago, Which was recognized by the Veterans Adm inistration, then the rest of the government as a legitimate religion.Still there are evangelical types who still get in my face and try to save me from imaginary (to me) monsters. I was raised in a catholic household. Since the majority against this are Christians and I know what it means to be Christian, I want to know how you can UT this much energy into complaining about same sex marriage when there are still homeless people, starving children, all over our country and the planet to take care of. How can you put complaining about homosexuals on a higher priority than starving children?I think even Jesus would say homosexuality is wrong, but spend his time feeding the children, preach but not force. Homosexuals, Offer a compromise, take the unions and get your foot in the door. Even though one law wiped out slavery, the civil rights movement took a long time, and it came in stages. Even when other regress was made, interracial marriages still had to be overcome. Get the civil uni ons, push to get it to the federal level, get more equal footing, then when it is almost the same, push to call it marriage.I think you have to work on people a few at a time. Pushing against that many people all at once isn't going to get you far. Logically, why should same sex marriages be outlawed? How many religions are out there, and how many claim to be the one true way to God? There are a few that don't recognize only one god, then there are the atheists who believe there is no god. If we re not going to dictate a religion, we cannot endorse any religions views on marriage.If our laws state that government and religion must be separate, why then, are we even debating the notions that the marriage defined in the bible is the only acceptable definition, when marriage is a legal institution? Unfortunately humans are an emotional creature. Some people so believe there is going to be hell to pay for homosexuality, those people have that right. Others believe that first group is ou t of their minds, they are within their rights. People are beginning to realize the ideals of he past don't hold up to intellectual scrutiny.Some, well many, people are trying to hold on to a tradition, one that they have believed in since they can remember. Every step we move away from that as a society, chips away at the foundations of their beliefs. Change is hard for some; they may have to accept the changes reluctantly. We are getting there though, these same people who are trying to hold on to outdated ideas, which are thousands of years old, have accepted women are out of the kitchen and the colored are out of the fields and the earth is round and goes round the sun.

Battle of Chantilly - Civil War Battle of Chantilly

The Battle of Chantilly was fought on September 1, 1862, during the American Civil War (1861-1865). Armies and Commanders Union Major General Philip KearnyMajor General Isaac Stevensapprox. 6,000 Confederate Major General Thomas Stonewall JacksonMajor General J.E.B. Stuartapprox. 15,000 Background Defeated at the Second Battle of Manassas, Major General John Popes Army of Virginia retreated east and re-concentrated around Centreville, VA. Weary from the fighting, General Robert E. Lee did not immediately pursue the retreating Federals. This pause allowed Pope to be reinforced by troops arriving from Major General George B. McClellans failed Peninsula Campaign. Despite possessing fresh troops, Popes nerve was failing and he decided to continue falling back towards the Washington defenses. This movement was soon checked by Union General-in-Chief Henry Halleck who ordered him to attack Lee. As a result of pressure from Halleck, Pope issued orders for an advance against Lees position at Manassas on August 31. That same day, Lee directed Major General Thomas Stonewall Jackson to take his Left Wing, Army of Northern Virginia in a flanking march to the northeast with the goal of circling Popes army and cutting off its line of retreat by capturing the vital crossroads of Jermantown, VA. Moving out, Jacksons men marched up Gum Springs Road before turning east on Little River Turnpike and camping for the night at Pleasant Valley. For much of the night, Pope was unaware that his flank was in peril (Map). The Union Response During the night, Pope learned that Major General J.E.B. Stuarts Confederate cavalry had shelled the Jermantown crossroads. While this report was initially dismissed a subsequent one detailing a large mass of infantry on the turnpike elicited a response. Realizing the danger, Pope canceled the attack on Lee and began shifting men to ensure that his line of retreat to Washington was protected. Among these moves was ordering Major General Joseph Hooker to reinforce Jermantown. On the road since 7:00 AM, Jackson halted at Ox Hill, near Chantilly, upon learning of Hookers presence. Still unsure of Jacksons intentions, Pope dispatched Brigadier General Isaac Stevens division (IX Corps) north to establish a defensive line across Little River Turnpike, approximately two miles west of Jermantown. On the road by 1:00 PM, it was soon followed by Major General Jesse Renos division (IX Corps). Around 4:00 PM, Jackson was alerted to the approach of Union forces from the south. To counter this, he ordered Major General A.P. Hill to take two brigades to investigate. Holding his men in trees along the northern edge of the Reid Farm, he pushed skirmishers across the field to the south. Battle Is Joined Arriving south of the farm, Stevens also sent skirmishers forward driving back the Confederates. As Stevens division arrived on the scene, Jackson began deploying additional troops to the east. Forming his division to attack, Stevens was soon joined by Reno who brought up Colonel Edward Ferreros brigade. Ill, Reno assigned Ferreros men to cover the Union right but left tactical control of the fighting to Stevens, who sent an aide to seek additional men. As Stevens prepared to advance, what had been a steady rain increased to a heavy downpour damaging cartridges on both sides. Pushing across open terrain and a cornfield, the Union troops found the going hard as the rain turned the ground into mud. Engaging Confederate forces, Stevens sought to press his attack. Taking the colors of the 79th New York State Infantry, he led his men forward into the woods. Mounting a fence, he was struck in the head and killed. Surging into the woods, the Union troops began a furious fight with the enemy. With Stevens death, the command devolved to Colonel Benjamin Christ. After nearly an hour of fighting, the Union forces began to run low on ammunition. With two regiments shattered, Christ ordered his men to fall back across the fields. As they did so, Union reinforcements began to reach the field. Stevens aide had encountered Major General Philip Kearny who began rushing his division to the scene. Arriving around 5:15 PM with Brigadier General David Birneys brigade, Kearny began preparing for an assault on the Confederate position. Consulting with Reno, he received assurances that the remnants of Stevens division would support the attack. Taking advantage of the lull in the fighting, Jackson adjusted his lines to meet the threat and moved fresh troops forward. Advancing, Birney quickly realized that his right was not being supported. While he requested Colonel Orlando Poes brigade to come up to support him, Kearny began seeking immediate aid. Racing across the field, he ordered the 21st Massachusetts from Ferreros brigade to Birneys right. Annoyed by the regiments slow advance, Kearny rode forward to scout the cornfield himself. In doing so, he ventured too close to the enemy lines and was killed. After Kearnys death, the fighting continued until 6:30 PM with little result. With darkness setting in and little usable ammunition, both sides broke off the action. Aftermath of the Battle of Chantilly Having failed in his goal to cut off Popes army, Jackson began falling back from Ox Hill around 11:00 that night leaving the Union forces in control of the field. Union troops departed around 2:30 AM on September 2 with orders to rejoin the retreat towards Washington. In the fighting at Chantilly, Union forces suffered around 1,300 casualties, including both Stevens and Kearny, while Confederate losses numbered around 800. The Battle of Chantilly effectively concluded the Northern Virginia Campaign. With Pope no longer a threat, Lee turned west to begin his invasion of Maryland which would culminate over two weeks later at the Battle of Antietam. Selected Sources CWPT: Battle of ChantillyHistory of War: Battle of ChantillyCWSAC: Battle of Chantilly