3/19/13

The quality of the Census Bureau's statistics is highly disappointing


Looking closer at the household income distribution reported by the Census Bureau I found an extremely confusing conflict of data on Gini ratio. There are two tables providing annual Gini ratio estimates for all households: “HINC-01. Selected Characteristics of Households, by Total Money” and “Table H-4.  Gini Ratios for Households, by Race and Hispanic Origin of Householder:  1967 to 2011”. The former estimates are available since 1998 in “Detailed Tables”. Figure 1 reveals a dramatic difference between these two estimates for the same years. The HINC-01 time series does not show any Gini ratio increase between 1998 and 2008 unlike the H-4 series.

There is a dramatic 0.02 step in 2009 in the HINC-01 series, which is actually fully related to the change in bin counting in 2009: the original $2500 bins between $0 and $100,000 were replaced by $5000 bins between $0 and $200,000. The change in the range and granularity of data resulted in the observed Gini ratio shift. Figure 2 displays the Lorenz curves for the years between 1994 and 2011 as obtained from the household income distributions in the relevant HINC-01 tables. The Gini ratio step of 0.02 is explained by the difference between the 2008 and 2009 Lorenz curves. Therefore, it is of artificial character  and the HINC-01 curve would be at the level of 0.45 between 2009 and 2011 if to retain the $2500 bins and $100,000 range.

We have recalculated the Gini ratio for all years between 1994 and 2011 from the original household income distribution and found that the calculated curve is in excellent agreement with the HINC-01 one between 2005 and 2011 and coincides with the HINC-4 curve from 1994 to 1996.

These observation are extremely confusing and likely manifest internal changes in the CB procedures of Gini ratio estimation and publication. We cannot understand why formally identical time series differ so much and why the HINC-4 curve demonstrates a growth tendency while the underlying data do not show any reason for that. This difference has also many political implications since the research community, officials, media, and the blogosphere all discuss the growth in household Gini, which is not the case.   
Figure 1. Gini ratios from HINC-01 (detailed)  and HINC-4 (historical) tables. 


Figure 2. The evolution of the Lorenz curves for the household income distribution between 1994 and 2011 in the USA. In 2009, the bin counting was changed from $2500 in the range to $100,000 to $5000 with the upper bin between $195,000 and $200,000.

2/27/13

Waveform cross correlation for seismic monitoring of underground nuclear explosions. Part I: Grand master events

A new paper is now available via arxiv.org:

Abstract

Seismic monitoring of the Comprehensive Nuclear-Test-Ban Treaty using waveform cross correlation requires a uniform coverage of the globe with master events well recorded at array stations of the International Monitoring System. The essence of cross correlation as a monitoring tool consists in a continuous comparison of digital waveforms at a given station with waveform templates from the global set of master events. At array stations, cross correlation demonstrates a higher resolution because the time delays at individual sensors from master and slave events are the same but they may differ from theoretical ones used in standard beamforming. In the regions where master events and thus waveform templates are available, one can reduce the amplitude threshold of signal detection by a factor of 2 to 3 relative to standard beamforming and STA/LTA detector used at the International Data Centre. The gain in sensitivity corresponds to a body wave magnitude reduction by 0.3 to 0.4 units and doubles the number of detected events. This gain is crucial for seismic monitoring under the CTBT. The coverage by real master events is sparse and confined to areas with historical seismicity, however. In two parts of this study, we investigate the possibility to populate the global grid with real and synthetic master events. In Part I, we replicate a high-quality master event over a regular grid several hundred kilometers from its actual position. In Part II, we model waveform templates using synthetic seismograms with the aim to apply them in aseismic zones. Both approaches are tested using the aftershock sequence of the April 11, 2012 Sumatera earthquake (Ms(IDC)=8.2). We used sixteen master events to recover the aftershocks in the Reviewed Event Bulletin of the IDC.

PDF copy of the paper

Re-post

starshinazapasa

Журнал Аркадия Бабченко


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Законопроект "Об оскорблении чувств младших научных сотрудников"
starshinazapasa
Как человек, верующий исключительно в науку, начал разрабатывать законопроект об оскорблении чувств доцентов, лаборантов и прочих ученых мужей. Стану депутатом - внесу в Думу.

За оскорбление "научных чувств ученых" - от трех до пяти. Формулировка специально будет максимально расплывчатой и неконкретной, чтобы можно было посадить любого. Ляпнул, что дважды два пять - и на двушечку без скощухи. Будьте любезны, присядьте пожалуйста.
За танцы и пение на кафедре (особенно в балаклавах) - два года.
Книги, тетради, учебники, карандаши, ай-пады и пр. и пр. можно будет покупать только в университетской лавке. Учебные пособия, купленные вне университетской лавки, будут считаться антинаучными и знания не принесут.
Российская Академия Наук получит право беспошлинной торговли водкой и сигаретами.
В школах и детских садах будет введено изучение теории Большого Взрыва.
Президент Академии Наук будет ездить на двух "Кадиллаках", которые загоняют в специальный железнодорожный вагон. Охранять его будут сотрудники ФСО. Один, специально приставленный, перед посадкой в автомобиль будет складывать знак Интеграла у него на профессорской шапочке.
Президент Академии Наук будет ездить с мигалкой.


В каждой деревне будет построено по академии или как минимум университету шаговой доступности. Детские сады, библиотеки, общественная собственность - будут отчуждены в их пользу. Жители Валаама будут выселены повторно. Так, чисто за компанию.
Раз в год, в день Большого Взрыва, все вещество, над которым любой лаборант или МНС прочитает теорему Ферма - становится антивеществом. Из-за чего приобретает лечебные свойства, а также не будет тухнуть на протяжении всего остального года.
Здание Академии Наук будет находиться на балансе города. Но внутреннее пространство будет принадлежать Московской Профессуре. Автомойка, банкетные залы, торговые точки - также будут принадлежать Московской Профессуре и не будут облагаться налогом. Потому как будут производить не торговлю, а дарение в обмен на дензнаки по строго установленной таксе.
Засорение нанопылью старых научных фолиантов карается штрафом в 20 млн. рублей.
Появление Президента Академии Наук на публике без часов "Брегетт" не допускается.
В армии будет введен институт Военных Научных Сотрудников. В каждой части будет построено по университету.
Оскорбление в блогах Президента Академии Наук будет преследоваться по закону. ФСБ будет предложено "более дерзко" расследовать такие преступления.
Мы уйдем от вульгарного примитивного понимания креационизма.
Ученых тыкать в каждую телепередачу по поводу и без повода.
За отрицание теории Дарвина будет введена уголовная ответственность.
При попадании даже самых младших научных сотрудников все видеозаписи ДТП мгновенно аннигилируются.
На Московскую же Профессуру с мигалками действие ПДД, а также административного и уголовного кодексов - не распространяется.
Если какой-нибудь председатель ОЗПП Михаил Аншаков вздумает задаться вопросом, почему наше дарение в обмен на строго фиксированную таксу в Храме Науки не является торговлей, а также почему автомойки и прибыль - наша, а ремонт и поддержание здания - на балансе города, бить его по башке монтировкой нещадно, обвинять в клевете и заводить уголовные дела

2/21/13

Re-published from oilprice.com

The End Game for Oil & Gas Juniors: Interview with Chris Cooper

By James Stafford | Wed, 13 February 2013 23:19 | 0
The oil and gas game can be a tricky one for junior companies, but if played right the pay-off can be massive. At a time when juniors are risking a lot in volatile venues in the Middle East and Africa, Canada’s Aroway Energy (ARW) is planting its feet firmly in homeland soil and in conventional plays.
Why? Because for the smaller juniors this is not a long-term game and blowing all your capital to drill a single unconventional well in a risky frontier won’t pay off. Canada still has plenty to offer for juniors, even though you have to kiss plenty of frogs to find the prince. The end game, after all, is merger and acquisition.
In an exclusive interview with Oilprice.com, Aroway CEO Chris Cooper discusses:
• How to make or break a junior oil and gas company
• Why rail is becoming more attractive than pipeline transit
• Why most juniors won’t make it big in risky frontiers
• Why Keystone XL will get the green light
• Why oil and gas prices will increase
• Why the smaller juniors will stick to the conventional plays
• How the asset market is heating up … and what is ideal
• Why having control of infrastructure is key to success
• Where Canada’s oil and gas industry will be in a decade
• What every junior’s goal should be
Interview by James Stafford of Oilprice.com
James Stafford: Junior oil companies have been storming the scene with some bold investments in tricky frontier areas. Where do you see this going and what will the next phase for the juniors be? Where will the action be, in conventional or unconventional plays?
Chris Cooper: I am a big believer in the conventional plays. I find that the non-conventional plays are turning into more of a game for the intermediate-size companies primarily as a result of the capital that is required to exploit the resources. Horizontal wells with multi-stage fracturing is an expensive game. I find that the conventional plays expose juniors to a less risky scenario with higher returns on investment and longer-term production more often than not.
Given the current state of the capital markets and the scarcity of funding, I think the smaller juniors will continue to play in the conventional arena.
James Stafford: What’s the ideal partner for a junior company, and what can make or break it for a junior?
Chris Cooper: As far as make or breaking a junior, I believe you need to minimize the company’s risk by drilling wells that are going to give you good internal rates of return and steady production; a good mix of development and exploration wells. It is also very good to have a good operator that is responsible in keeping a control on costs.
James Stafford: What separates the good management teams from the mediocre in the Canadian junior oilpatch?
Chris Cooper: Management teams that have built and sold companies in the past have a responsible, methodical approach to how they run their businesses. More often than not, these teams do not try to re-invent themselves by drilling wells and formations that they have not done in the past. They continue to focus on what they know best, whether it be drilling in the Peace River Arch, chasing Leduc wells, or focusing on cardium wells. They often do not stray from their formulas and that is why they are good teams.
James Stafford: More Canadian oil is now being marketed by rail. Can you put the rail versus pipeline transport comparisons into perspective for us from a Canadian operating perspective?
Chris Cooper: A lot of companies, including Aroway, are capitalizing on the benefits of moving their oil via rail as opposed to pipeline. I think it will increase our netback, our profit per barrel, by several dollars immediately.
For instance, before we purchased our West Hazel Property in Skaskatchewan, the owners would truck to Talisman or another big operator that was pipeline-connected. Then, once the oil got to the pipeline-connected operator, they had to pay a certain amount of money to get it in the pipeline for diluents to meet pipeline specifications. Then they had to pay for the pipeline tariff and then they got the price the pipeline operator provided wherever they were on the pipeline.
So for example, the last month we got $53 to $54 a barrel, after the blend-in tariff for our West Hazel production, which is probably the lowest you’re going to see for a long time. Our netback on that oil was still greater than $20 a barrel. But for that $53.32 a barrel we sold, if transported by rail, we remove the pipeline tariff, we remove the blend for the diluents and we get $9 more added to the netback value.
So what we’ll end up doing is trucking our oil from the field to a company called Altex Energy, which is partly owned by Shell Canada. Shell owns all the railway cars and all these railway cars get filled up with heavy crude and shipped down to their Port Arthur facility on the Gulf Coast. At Port Arthur what typically happens to our crude--because it’s somewhere between 11 and 13 degree oil—is it goes straight into bunker fuel for ships.
So the refinery doesn’t have to touch it in some cases and that’s where we get a pretty substantial bump. Then you’re not subject to pipeline apportion and issues. It just opens up whole new markets for you.

At the end of the day we will get somewhere around $66 or $63 a barrel this month and then we’re going to bump that up by another $9 next month by taking all the crude we have in West Hazel by rail. So our netback will be $35 to $40--and that’s just the West Hazel crude.
James Stafford: What is the market like for assets right now, from a junior’s perspective? What’s the ideal prospect?
Chris Cooper: Asset sales are heating up. We are finding that there are a lot of assets being marketed through companies like Sayer and NRG Divestments. There are also several larger brokerage firms representing companies for “strategic alternatives.”
As an example, Aroway just picked up a great producing asset in Saskatchewan for $10,000/flowing barrel. The market for similar assets in Saskatchewan at that time was about $40,000/flowing barrel. Companies need to exercise patience and do their due diligence. Not to mention kissing a lot of frogs to find these types of assets. They are out there.

James Stafford: A lot of North American juniors are hitting the riskier frontiers with all they’ve got these days—from Iraqi Kurdistan to Sudan, even Somalia. Why are they willing to take this risk and is it paying off?
Chris Cooper: With higher risk comes higher reward, but I don’t think it is paying off in the broader sense. Sure, there are 2 or 3 juniors that have hit home runs, but more often than not a junior is going into those types of plays with only $5 or $10 million in the treasury and they blow this after drilling just one well. I have always believed there is great opportunity offshore, but the risks are lower and infrastructure and political stability in North America is in place. There is plenty of opportunity in North America.
James Stafford: Related to this, where do you see Canada’s oil and gas industry 10 years from now?
Chris Cooper: I see the oil and gas industry in Canada continuing to grow with the advancement of new drilling techniques and new innovations in exploiting existing pools to increase the recoverability. We have a stable political system in place which enables business opportunity to grow in Canada.
James Stafford: We hear a lot about Alberta, but what kind opportunities are we looking at in Saskatchewan?
Chris Cooper: Saskatchewan is definitely open for business. The royalties paid in Saskatchewan are very low and the production opportunities are very good. We are actively looking for new opportunities in Saskatchewan.

James Stafford: Do you lend any significance to Canadian media reports that the Cabinet is reviewing some new legislation that would set stiff payouts for the oil industry for accidents?
Chris Cooper: Personally, I think it is part of the grand plan to help the approval process. My theory is that the Canadian government will lay out a plan for big fines and then push to have the pipelines approved. The construction of pipeline projects creates jobs and would be good for the economy.
James Stafford: Do you think this is simply a carrot for the protesters at a time when the Enbridge hearings are raising tensions?
Chris Cooper: There will always be protesters.
James Stafford: What do you see happening to energy markets in 2013?
Chris Cooper: I see the price of oil and gas both increasing. They are depleting resources….it’s an inevitable function of supply and demand.
James Stafford: What are your views on the Keystone XL Pipeline? Do you think it is likely that Obama will approve its construction, and if so how will this affect your business?
Chris Cooper: I think he will approve it. The Governor of Nebraska gave the new route the okay. I think now that Obama has been re-elected he will go ahead and approve. Again, that is a lot of job-creation for an economy that is struggling. More pipelines are good for Canadian producers as it helps get our oil to market.
James Stafford: What are Aroway’s top three plays, and why?
Aroway plays
Chris Cooper: Our current plays all have different risk and production profiles. We have a large inventory and land spread in our JV lands in the Peace River Arch, which provide a healthy mix of development and exploration risk. Very big upside in this play.
Our West hazel production play is a very stable, long-term production scenario that we feel will provide great cash flow and netbacks to the company. For little investment we feel we can substantially increase production at West Hazel.
Aroway Primary Plays
Our Kirkpatrick Lake and Little bow lands in central Alberta are also very prospective properties that have the ability to turn into new core areas for the company. All our properties are oil focused and are highly prospective.
James Stafford: What can we expect from Aroway in 2013?
Chris Cooper: I am confident 2013 will be a big growth year for Aroway. We will continue to drill on our existing properties and leverage our production and financial position to take advantage of existing and upcoming opportunities in the sector as far as acquisitions and potential farm-in opportunities. We are confident it will be a big year for our shareholders.
James Stafford: 2013 has been touted as the year of the merger and acquisition. As one of the hottest investments around at the moment, do you think that Canadian junior oil & gas companies, like yourselves, will become a favoured target for larger oil companies looking to expand?
Chris Cooper: I think I can speak for most junior companies when I say, ‘I hope so’. There are a lot of big companies that need to fill the production gaps in their natural depletion, thus in some cases forcing big companies to do that through acquisition. I think the goal for most juniors is to be taken over by a bigger company at a nice premium for the shareholders.
James Stafford: Thanks for your time Chris. For those of you interested in finding out more about Aroway please visit their website at: http://www.arowayenergy.com/

1/23/13

Re-published from Oilprice.com

Kenyan Oil, Hot and Getting Hotter: Interview with Taipan's Maxwell Birley
Kenya has become the hottest oil and gas venue in East Africa since big discoveries were made in the country's virgin oilfields last April. All eyes are on Kenya in 2013 to see how quickly--and economically they can develop those discoveries into production.
Nairobi based Taipan Resources Inc. (TPN-TSXV; TAIPF-PINK) is the 4th largest acreage owner in Kenya, and is getting ready to carry out seismic on Block 2B. They recently attracted Maxwell Birley as CEO. Mr. Birley has been instrumental in discovering more than 2 billion barrels of oil equivalent in his 30-year career—much of it in Africa and Asia.
In an exclusive interview with Oilprice.com, Taipan CEO Maxwell Birley discusses:
• Why Kenya is the hottest venue in East Africa
• Why 2013 will be a stellar year for Kenya
• Why the regulatory environment remains attractive
• Why Kenya outranks its neighbours
• Why infrastructure will be in place in time for commercial activity
• Why this venue is good for the juniors
• Why the Somalia security risk remains low
• What Taipan is really chasing
Interview by James Stafford of Oilprice.com
James Stafford: There were some major discoveries in Kenya last year. Could you give me some colour on these discoveries that has the market thinking Kenya is now one of the hottest exploration spots on earth?
Maxwell Birley: There are a couple—or 2 billion--reasons actually. First, two recent discoveries by Tullow in the Tertiary Lokichar basin of Kenya are in similar geological settings as the discoveries also made by Tullow in the Albertine Basin in Uganda, just to the west.
Uganda has over 2 billion barrels, and the discoveries are similar enough that one could assume the eventual size of the resources in the Lokichar basin could be in the billions of barrels range as well.
There are also other Tertiary basins in Kenya that are attractive. Based on geochemical work we recently did it's possible that the eventual hydrocarbon resource size for the whole of Kenya could be much higher than this.
Being specific the unrisked prospective resources for Taipan's acreage in Kenya is 530 million barrels. We also believe that this estimate will likely increase to approximately 1.0 billion on completion of our studies.

These estimates are for only 2 blocks in Kenya, if this is reasonably extrapolated to other blocks across the country one can easily forecast very significant hydrocarbon resource sizes indeed.
James Stafford: What's the easiest and most challenging thing about working with the Kenyan government and in the Kenyan political climate?
Maxwell Birley: The Ministry of Energy is always ready for a meeting. They listen to our concerns and take the appropriate action. They quickly follow up and give us the support that we need with other Ministries. In the field the local administration is also very helpful. We have regular meetings to make sure our work continues without a hitch.
With regard to the political climate, there is an election coming up in March 2013. We're making arrangements so that we do not have a slowdown in seismic operations during that period. The last elections in 2007 were associated with some “geographically limited” security issues, however these were located far from our areas of operation, so we are not expecting the elections to have much impact on our operations.
James Stafford: The Kenyan government is reviewing its oil and gas regulations. Among the suggested amendments is one that would see the National Oil Corporation (NOC) get a 25% interest in oil properties that foreign firms are operating in Kenya, but this would put the government in a precarious position vis-à-vis attracting investors. How do you see this playing out in the end?
Maxwell Birley: The government is reviewing the terms that shall apply for licences/contracts that will be granted in the future. Oil companies will review all the terms on offer at the time of bid submission and compare them to the attractiveness of the acreage.
James Stafford: In November last year, Kenya expelled Norwegian Statoil, after revoking its exploration license. Is Nairobi increasingly ‘policing' exploration, and what will this mean for investors in the near/medium term?
Maxwell Birley: One of the main functions of the Ministry is to regulate the companies undertaking exploration activities in Kenya. We feel confident, as in many other countries where we have worked, that if you carry out your commitments in the timeframe of the PSC then your license is 100% secure. If we decide to go into the next phases of exploration on Block 2B we can continue to explore for hydrocarbons on the block for another 4.5 years without concerns to the validity of our contract.
James Stafford: How does the industry view the financial terms offered by Nairobi in oil and gas?
Maxwell Birley: We believe the terms are reasonably attractive, at least for an oil discovery. The reason that only a few exploration wells were drilled in the past was due to the lack of exploration success—and this was driven by the lack of understanding by the oil companies of the basins. It wasn't because of financial terms offered by the government.
Now that a discovery has been made and our knowledge is increasing, we are going to see a significant increase in drilling activity and therefore reserve additions to the country.
James Stafford: Is Kenya becoming more a game for the majors rather than the juniors, and do you think we will see more joint ventures in the near future?
Maxwell Birley: In our opinion there is a place for small companies at every stage of the development of an oil province. But it's definitely good news for those juniors with large land positions already in the country. The early movers--i.e. the companies like Taipan that acquired their acreage before the oil was discovered—will benefit from the recent oil discoveries. Most of the more prospective acreage has now been leased and therefore the competition for land is increasing.
As large volumes of oil are discovered, the large independent and Majors will start to notice the country more and more. The Majors—due to their size and complexity—tend to be exploration risk averse and prefer to concentrate on large, lower-risk developments.
James Stafford: How would you like to see Nairobi interact with the energy sector moving forward? And how does Kenya compare with other venues in the region like Ethiopia, Tanzania, and Sudan?
Maxwell Birley: There is no doubt that Nairobi is a premium location for business, tourism and families. This is illustrated by the fact that many multi-nationals operating in the sub-Sarahan African region have their head offices in Nairobi. Regarding interaction, it is the oil industry that will need to develop an active and well respected industry body so that broad industry issues can be discussed at the higher levels.
James Stafford: Kenya is clearly the East African leader in oil infrastructure, and is now starting the Lamu Port-South Sudan-Ethiopia Transit corridor (LAPSSET) project. But it will cost $25 billion for the roads, the 1200 km pipeline and 120,000 barrel-per-day refinery. How feasible do think this project is and why? Is it feasible in the timeframe projected by Nairobi?
Maxwell Birley: The resources in Uganda and to some extend south Sudan must be exported. A pipeline through Kenya seems to be the most feasible.
Regarding the time line, having 2.5 billion barrels sitting in the ground just west of Kenya in Uganda is a really strong motivation to build the pipeline quickly. In South Sudan I think they started pumping oil back up north again now, but I think they will want to go through Kenya in the near future.
Whether it's LAPSSET or the Tullow consortium someone is going to build a pipeline through Kenya to the coast in the next few years. We think the pipeline will be located within 175 kilometres from our acreage. The pipeline will be good for everybody in the region but it should be particularly positive for us.
So when we make a discovery on Block 2B, the pipeline will be in the construction phase. In the interim we'll truck the oil by bowser the early production from the fields. Then, depending on the size of any discoveries, we'll build a connecting pipeline into the pipeline from Uganda. I think we're in a very fortunate position now.
James Stafford: In terms of exploration what are the ‘sweet spots' in Kenya?
Maxwell Birley: Definitely the Anza Basin. Currently, the proven sweet spots are in the Tertiary sediments of the rift basins of Uganda and Kenya. More specifically to Kenya in the Lokichar Basin as proven by the Ngamia and Twiga wells by Africa Oil.
These basins form part of the larger East African Rift system. This is a very extensive rift system and many new plays will be discovered in the next few years. The Anza Basin is the largest of these East African rift basins and 10 times the size of Uganda's Albertine Basin and Kenya's Lokichar Basin. This rift contains Jurassic, Cretaceous and Tertiary sediments.
Taipan is exploring for oil in the south eastern end of the Anza basin. Located on block 2B we have proven more than 9,500 feet of Tertiary section on the block. From the geochemical modelling we have undertaken we see the same oil source rocks in the Anza Basin that are present in the Lokichar basin, which are highly likely to be mature for oil generation on Block 2B. In addition we also believe that more oil discoveries will be made in the Cretaceous and Jurassic basins if you can find favourable places to drill.
James Stafford: What has Taipan's proprietary technical work in Block 2B in the Anza Basin demonstrated so far?
Maxwell Birley: The Anza basin has proven oil-prone Cretaceous source that in places is potentially in the gas window (Bogal gas discovery), however our technical work has also demonstrated that the basin has an active Tertiary lacustrine (lake) oil source that is in the oil window. Consequently, the Anza basin has an excellent chance of being a much more significant oil producing basin than the small rift basins that have so far been discovered.
James Stafford: And that's what you're really chasing here—with these roughly 10 million acres in the Anza Basin—the tertiary play...
Maxwell Birley: Agreed. What we're primarily chasing in Block 2B is the same Tertiary oil play that Tullow inherited originally in Uganda. The discoveries there were the main reason Africa Oil and Tullow drilled the Ngamia and Twiga oil wells in Kenya—which have also been very successful. Of course, don't overlook the fact we also have a secondary Cretaceous oil play in the block, that appears to be broadly analogous to the Cretaceous plays present in the Muglad Melut basins of southern Sudan and is the main focus of exploration efforts in Block 10A, operated by Africa Oil Corp.
Regarding the rest of our acreage, in Block 1 for example where we have a 20% interest in a 31,781 Km2 block we are chasing older Cretaceous, Jurassic and Permo-Triassic plays. The block is located in an extension of the successful Ogaden Basin of Ethiopia and Somalia. We think the block will be very prospective as it is surrounded by oil seeps and a well that recovered oil on test.
The 2 blocks combined makes us the 4th largest acreage holder in Kenya. In terms of near-term drilling and catalysts in the region, we have Tertiary, Cretaceous and Jurassic plays on Block 1 and Block 2B that will be drilled in the next 12 to 18 months.
James Stafford: Tell us what 2013 will look like for exploration in Kenya?
Maxwell Birley: Ten exploration wells should be drilled in Kenya in 2013. Based on the previous success rate it is expected that a significant number of these will be discoveries. Tullow will continue drilling wells on Blocks 10BB and 13T on the west side of the country to find more oil in that string of pearls.
Also we shall shortly get the results of the Paipai-1 well which is currently drilling in northern part of the Anza Basin. The well is testing Cretaceous & Jurassic plays, with a potential 121 million barrels. Other wells including Sabisa and Kinyonga also expected to be drilled in 2013.
James Stafford: For Kenya, a discovery at Paipai-1 would prove that oil discoveries of Sudan extend into Kenya. What would it mean for Taipan?
Maxwell Birley: There have already been Cretaceous gas discoveries in Kenya. Taipan believes that if you can find the Cretaceous that has not been buried too deep it will be prospective for oil. However we think the Paipai well is very high risk as it seems likely to be a recent tectonic inversion structure and therefore may be breached by recent faulting. We think we can find on Block 2B Cretaceous structures that are oil prone that have not been breached by recent faulting. So if that well does come in then it is going to be good news for the Anza Basin in general, but if dry it will not write off the Cretaceous potential in our block. Having said that I should point out that this is not our main focus at this time.
James Stafford: What about other prospects, like the Kinyonga well?
Maxwell Birley: Kinyonga is the next big prospect that is going to be drilled by Africa Oil Corp. and that is very meaningful for us. Kinyonga, which is on Block 9, will be located relatively close to our block, is both Tertiary and Cretaceous prospect. It has an unrisked resource estimate of 320 million barrels prospective, and it is one of the largest prospects in Africa Oil's portfolio of drilling targets. Africa Oil also has another prospect called Pundamilia which is even closer to our block. This prospect has a unrisked resource Best estimate of 402 million barrels and a High estimate of 952 million barrels which I believe is the largest prospect in Africa Oil's portfolio.
James Stafford: And what is the status of Kinoyonga?
Maxwell Birley: The timeline Africa Oil report for Kinoyonga is the 2nd half of 2013.
James Stafford: That would be a pretty big corollary for Taipan ….
Maxwell Birley: I think that even prior to getting those drilling results; investors are going to become more aware that the Tertiary play extends into our block. This was proven by the Hothori well which encountered 9500 ft. of Tertiary sediments. Better than this based on seismic data we estimate that in parts of the block there could be greater than 15,000 feet of Tertiary sediments.
James Stafford: What can we expect from Taipan over the next six months?
Maxwell Birley: Taipan has contracted BGP to acquire up to 800 kms of 2D seismic survey and Arkex to acquire a block wide FTG survey both over Block 2B. The seismic will commence recording in January 2013 and the FTG in February. Both surveys will be completed and interpreted prior to the 1st June deadline to complete the work. We expect to enter the first additional exploration period and are planning on drilling a well late 2013 early 2014.
Taipan has a 20% interest in Block 1 where Afren has recorded 1900 kms of seismic data.
After the seismic has been processed and interpreted the company will commence preparations for well to be drilled in late 2013/early 2014.
James Stafford: What do you expect to learn from this North Eastern data?
Maxwell Birley: We will be acquiring world class seismic data with an extremely high fold in Block 2B. We may record data with fold as high as 540 (other operators in Kenya usually only record at 60 fold). We will do this so that we get excellent signal to noise ratio and seismic data improvement. This will then enable us to predict with some certainty the areas that have high shale to sand ratios. This in turn will indicate where the Tertiary lakes sediments were deposited. This will dramatically increase the chances of drilling a successful oil well.
James Stafford: Let's close off then with a note on security and Taipan's potential concerns in that area...
Maxwell Birley: Our acreage is in a remote region with very few inhabitants. We always take the appropriate health and safety precautions for example we've carried out detailed security risk assessments and we have visited the areas on a number of occasions. We work with other operators and security companies to ensure we have good local information.
To mitigate the risk, we have 50 to 60 armed police on the seismic crew to supply physical security. More importantly we have excellent support from the government and local authorities. We are in the process of undertaking some CSR water projects so that local people benefit from our activities. We also have a team from the area that is in the field communicating continuously to ensure that the local community understands what we are doing and observes the benefits of working with Taipan.
So in summary, we take it all pretty seriously. There are risks, however, it's a place where you can work, so we're being very respectful and careful to nurture successful relationships.
James Stafford: Has Kenya's intervention in Somalia had any impact on exploration in the border area?
Maxwell Birley: Yes, it has ensured that oil companies can undertake their work in relatively safe conditions.
James Stafford: Mr. Birley, best of luck. Thank you for your time and we will check in with you later in the year.

1/22/13

The use of synthetic master events for waveform cross correlation

Another EGU 2013 abstract

Abstract

It has been clearly demonstrated that waveform cross correlation substantially improves signal detection, phase association and event building. These processes are inherently related to the Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring. The workhorse of cross correlation is the set of seismic master events (earthquakes or explosions) with high quality waveform templates recorded at array stations of the International Monitoring System (IMS). For the monitoring to be globally uniform, these master events have to be evenly distributed and

their template waveforms should be representative and pure. However, global seismicity is characterized by a non-uniform distribution. Therefore, the master events selected from the Reviewed Event Bulletin (REB) produced by the International Data Centre (IDC) can be found in the areas constrained by the global seismicity. There are two principal possibilities to populate the globe with master events: to replicate real REB events or to build synthetic events. Here we compare the performance of these two approaches as applied to the aftershock sequence of the April 11, 2012 Sumatera earthquake. To compute synthetic waveforms, we use AK135 teleseismic velocity model and local CRUST-2 models for source and receiver, and four different source functions representing three different source mechanisms for earthquakes and one for explosion. The synthetic modelling is performed for teleseismic events and based on the stationary phase approximation to a wave equation solution developed by J. Hudson.

The grid covering the aftershock area consists of 16 points. For each grid point, we find detections associated with real, replicated, and four versions of synthetic master events at seven IMS array stations, and then build event hypothesis using the Local Association (LA) procedure based on the clustering of origin times as estimated by back projection of the relevant arrival times with known master/station travel times. Then all conflicts between the hypotheses built by different masters for physically same events are resolved. There are two principal ways to compare the performance of actual, replicated, and synthetic master events: to compare the characteristics/distributions of detections (also station dependent) and those of event hypotheses. Both datasets have shown that the synthetic events provide the same overall performance as the real and replicated master events. The best performance is associated with the explosion source and the earthquake with the Harvard CMT solution for one of real events. When source mechanism and velocity model are appropriately chosen, the global grid of synthetic masters may allow a reduction in the magnitude threshold of seismic monitoring and improving the accuracy and uncertainty of event locations at the IDC to the level of the best located events. When a ground truth event is available, one can expand its influence over hundreds of kilometres.

 

Key words: array seismology, waveform cross correlation, synthetics, seismicity, master events, IDC, CTBT

Recovery of low-magnitude seismic events before the July 29, 2025, Kamchatka megathrust earthquake using waveform cross-correlation enhanced by the addition of stochastic noise

 Recovery of low-magnitude seismic events before the July 29, 2025, Kamchatka megathrust earthquake using waveform cross-correlation enhance...