Please contact us for other dates if these days are not suitable.
This tour takes you to the most beautiful areas of the southern Sweden, all from the deep spruce forests out to the coast with white beaches and small genuine villages far from all international fashion stores and hamburger chains. This is the genuine Sweden. When it comes to driving, we have parts of paved small countryside roads to roller coaster gravel roads and small dirt trails. Our tours are made to be as entertaining as possible, we love active driving and roads use to be empty. There is a day off at the coast to spend as you like, with several options to discover something special in the amazing area we are staying. On top on that we offer some activities in the evening, just to get the most out of your biking adventure. We often have access to the hotel´s spa or we have something special to do after driving. The service is there for you, we have comfortable 3 or 4 stars hotels also rewarded for their meals. If you bring your partner who does not ride a motor cycle we can offer him/her to go in our support minivan in which the luggage is transported.
We pick you up at the airport and take you to our hotel where we arranged dinner and will inform you about the tour.
Tour 125 km + warm-up.
After a substantial breakfast at the hotel we pick up our bikes. We will then practise a little on local gravel roads to prepare. We will try riding on different surfaces to do some brake and balance exercises, so that we get comfortable on our own test track during the morning. Just before lunch time we are off! We start with some alternate paths, gravel and asphalt, to take the ferry west to a superb fish restaurant where we will have lunch of freshly caught fish. After lunch we take smaller curving roads through the forests, passing small villages where time has stood still the last 50 years. When we arrive at our hotel in Hestra, located right at the river Nissan, we check into newly refurbished rooms. We then go to the shooting range to clay pigeon shooting with a shotgun, a fun activity that anyone can do even if you've never held a gun before. We will enjoy a 3 course dinner at the hotel, which is awarded for its good food and lovely environment.
We leave from Southern Sweden Ski Center. Within a few kilometers we will have tried several different surfaces – asphalt, gravel and even grass. Lovely roads up to Taberg hill, where we have lunch at one of the best views in Småland. After lunch we drive towards Eksjö, routes that will put a big smile on your face. The roads that wind inside the deep spruce and pine forests have limited visibility with blind curves, so you need to concentrate during this run. We arrive at our hotel, situated next to a lake. Dinner is served at the hotel, with a beautiful view of the lake. After dinner, we go swimming in the lake, with maybe a warm up in the sauna first. We round off the evening with some karaoke at the hotel, for those who feel in good voice.
We eat a buffet breakfast and set off on lovely gravel roads. In fact, during the day we ride a lot on rough gravel, which causes tyres to slip as it is so loose. Of course, we try to alternate different types of gravel. The ride today is very entertaining and beautiful, the scenery is great as we ride through hilly landscapes with small farms and with farmland mixed with forest. We make a stop at the Katthult farm which was the main scene character Emil by author Astrid Lindgren, in one of her many famous children's books – perhaps the most famous of her characters is Pippi Longstocking. We continue south and the landscape becomes flatter and the roads become faster. We follow Stångån some distance downstream and then take the bridge over it. We are going to Kosta, the center of the Swedish Kingdom of Crystal. The Kingdom of Crystal has made blown glass since 1742. Today you will be a visitor to some of the best utility glass and art glass in the world and will be able to go right up to the glass furnaces to see it created. In Kosta there is the chance of shopping for both glass and clothes in a 20,000 square meter area. The hotel has a spa and cuisine of international class and won major tourist prizes in Sweden. We have, as you would hope, access to the spa during our stay, and a 2 course supper.
In the morning after a buffet breakfast we look at how to do glass blowing, a craft that requires great skill and experience – it's wonderful to see how a piece of glass becomes a work of art. Then we leave Kosta and drive on, down to the Blekinge and Skåne border. Initially we're on pretty fast gravel roads, then more mixed surfaces with paths and winding roads. In this area there are plenty of small lakes, and roads run between these through forests and farmland. We will make a lunch stop at a restaurant to recover our energy so that we stay alert in the second half of the day. We're approaching Carl von Linné and IKEA country now, and our hotel is beautifully located on a peninsula. We eat dinner with a beautiful view over the lake at our hotel, where there is also free access to kayaking on the lake.
We leave the hotel in Älmhult and head for the border between Småland and Skåne where we run both faster and slower routes. Some of the faster routes have been used in the South Swedish Rally and has lovely curve combinations, where you just want to continue to turn right, left, right, left, and so on. On the slower roads the rhythm becomes different which requires a little more attention as the surface is shifting. The nature will also shift as we drive to the west coast. The landscape will open up with more farming land and we will also pass through flourishing beech forests. You will find a lot of scenic views along the west coast of Sweden. It is also one of the most popular areas for vacation among Swedes, because of its long white sand beaches and former fisher villages. We check in at the traditional hotel which was built in the 1800 century. Today it is modern and restored to meet the need of today's guests.
This day is dedicated for rest and recreation. We have the opportunity to visit some attractive places in this coastal area like Kullaberg, a nature reserve. It is a great area for hiking or do some other adventurous excursions. The minivan will be available to transport you to different interesting places during the day. Lunch and dinner are included.
This day we are heading north, after a tour on the peninsula where swedens best farming is and also some of its best view points. During the day we pass small lakes which are scattered in the forest landscape. We have sought out the best roads in the area and aim was to see you drive with a smile on your face all the time. In the afternoon we drive a couple of stages on quite fast gravel roads with hard surface, but there are even some paved roads, as we approach Varberg the landscape become more and open farmland. We check in at our 4 star spa hotel, renowned for its fine buffet with vegetarian, fish and meat dishes. It is a comfortable hotel situated next to the beach and we have free access to their spa. It is possible to book massage and different treatments (not included).
We leave the coast and plains and drive further north and into the wilderness. We will reach more hilly areas with great entertainment value when it comes to driving. This day we continue even further into the deep forests of Småland, through spruce and pine forests. The road surface varies from sandy to gravel with some larger stones. We will also ride on both softer and harder dirt roads. Some parts of our route have been used in South Swedish Rally and offer delicious curve combinations. Hopefully we can see some of the wild animals found in the forest. Something that is certain is that we will pass many of the red Småland cottages with white trim. In the afternoon we will eventually return to where we started our tour. We hope you by now got many new wonderful impressions and memories. We check the bikes in before making our way to a farewell dinner at a nice place.
After a full breakfast we will drop you off at the airport.
- Transfer from/to Copenhagen or Gothenburg airport.
-Enduro-helmet with integrated chin protector and goggles or full face helmet.
2650 EUR for riding in support vehicle.


any facade to suit your needs.
and is considered as one of the leading kitchen equipment supplier.
It is located at Al Suwaiq.
The company being managed by highly experienced management and behind the success of this company Mr. Firoz Moidoo, Managing Director, has been in the same business field for over 15 years in UAE. His experience and knowledge in the field of manufacturing, distribution and selling are the features that help in attaining the company's goal.
The company being managed by highly experienced management and behind the success of this company Mr. Firoz Moidoo, the partner, has been in the same business field for over 15 years in UAE.
Copyright © Al Fayrouz Kitchen 2015 All rights reserved.


text:
Carnival of Nuclear Bloggers 162
Atomic Power Review is proud to host another in a long line of pro-nuclear advocacy vehicles that we call the "Carnival." This feature rotates among pro-nuclear blogs each week, and presents the top stories of that week.
We've just come off a grand American Nuclear Society Annual Meeting, which I attended and reported on under contract to the American Nuclear Society. The topical meetings were great, and of course as with any such meeting the networking before and after the sessions were invaluable. Some of the links you'll see below relate to material delivered at the meeting.
But first... What is this?
You can click the photo to enlarge it. No hints this week -- and yes, this photo was very deliberately chosen to appear in this feature at this juncture.. in fact, I thought I'd picked the photo prior to the weekend but I changed photos at the last minute. You'll find out why later on. Now, the Carnival!
Next Big Future - Brian Wang
Japan has new nuclear safety guidelines: The Nuclear Regulation Authority said it would start accepting applications on July 8 from power companies seeking to restart their reactors. Seven companies have said they will apply to restart a total of 13 reactors across Japan. Japan has passed new safety guidelines.
Atomic Insights - Rod Adams
Defy Joe Romm's advice and watch Pandora's Promise: Joe Romm, the lead thinker at Climate Progress, has once again exposed the fact that he is not terribly serious about fighting climate change. In fact, he is so casual about the effort that he wants everyone to dismiss nuclear energy out of hand as being too expensive to matter, without even thinking about trying to solve the often solvable issue of cost. He does not want to deal with the discussion that might happen if people watch Pandora's Promise and begin to consider nuclear as an effective tool in an important struggle.
Yes Vermont Yankee - Meredith Angwin
Pandora's Promise: Nationwide Now In this post, Meredith Angwin compares reactions to the movie Pandora's Promise, particularly reactions by anti-nuclear activists. One nuclear opponent wrote: "For me, this film's strength was not that it changed my mind, which it did not, but that it expanded it." Another supposed environmentalist used the terms "hoax" and "liar" about the film. In other words, some people have open eyes. Other people keep their eyes shut, in order to defend themselves from inconvenient truths.
Hiroshima Syndrome - Leslie Corrice
The Hiroshima Syndrome covers two topics of import this week. First, in "Japan's Red Cross violates its moral imperative with too-low limits," we find that the Japan Red Cross Society (JRCS) has set a maximum radiation exposure limit of one millisievert per year for emergency response workers. The primary mission of these workers is saving the lives of survivable victims. To the contrary, it seems the JRCS is more concerned about avoidance of negligible radiation exposures than saving people's lives. Next, in "A New Fukushima Scare About Strontium-90," this past Wednesday Tokyo Electric Power Company said Strontium-90 was found in a groundwater sampling well near Fukushima Daiichi. The announcement has set off a tsunami of alarming press articles based on questionable evidence. Japan's press seems dedicated to keeping its readers in a state of fear.
ANS Nuclear Cafe - submitted by Paul Bowersox
The American Nuclear Society's Annual Meeting was held this past week in Atlanta, Georgia. The technical sessions there provided a great deal of timely and relevant information about nuclear energy and research; two were covered in some detail on the ANS Nuclear Cafe blog by Will Davis. First, a panel discussed the risks and challenges involved with Building New Nuclear Plants. Second, another expert panel discussed Supply Chain and Procurement Issues in Nuclear Energy. Both presentations carried important implications for the future of nuclear energy in this country, in both the areas of new construction and support for plants already operating.
Westinghouse has released a brand new television commercial entitled "We Are Nuclear Energy." This was debuted at the ANS Annual Meeting to round applause. See this link for the ANS Nuclear Cafe article on it.
We now get to the "What is this" feature that Atomic Power Review always has when it hosts the Carnival.
The illustration you saw earlier shows an artist's conception of the NEP-1 and NEP-2 units which were to have been built at the site of what had been the Charlestown Naval Air Station, Rhode Island. These units were ordered by New England Power (and other utilities) in May, 1974. In September, 1976, a construction permit was applied for. Some statistics (partly from the back of the post card whose front provided the illustration) are as follows:
Proposed Site - 604 acres
Total Estimated Cost - Over $1.5 billion
Scheduled Completion Dates - Unit 1, 1982; Unit 2, 1983.
Both units Westinghouse Pressurized Water Reactors. (Rated 1194 MWe each.)
Architect-Engineer: United Engineers & Constructors.
The project would have employed a peak construction force of over 2000 workers, and kept an operating and maintenance force of over 200 workers - greatly boosting the local economy, and providing GHG-free electricity 24 hours a day, rain or shine.
The project was cancelled in 1979, officially 0% complete. According to Energy Information Administration documents, the official reason was "reversal of economic advantage," with the footnote "it was determined that the implementation of conservation and load management programs, and the conversion to coal of existing units, could satisfy current and projected demand."
"Conversion to coal" is particularly stunning right now, immediately after the release of the movie Pandora's Promise, in which a number of former anti-nuclear activists detail their conversion to being pro-nuclear. How strange is it that prevention of a nuclear plant's construction was in part made possible by converting other units to coal.
The fact about this project's abandonment though is that a major deciding pressure was a bevy of lawsuits brought against the project by local "environmentalist" activists. Certainly, the downward trend in projected power requirements played a role - but so did obstruction by intervenors, better and more accurately named as "opponents."
This last described fact is appalling in light of converting plants to coal at the time. These lawsuits are no secret; look them up yourselves.
There was already a clearly established trend of nuclear plant delay and cancellation underway by the time the NEP units were cancelled in 1979. Below is a graph from a 1981 US DOE document entitled "Nuclear Power Program Information and Data."
Click the illustration to enlarge it. It's clear that the trend to having a net negative quantity if one only considers plants ordered annually and plants cancelled annually started in fact shortly after the NEP plants were ordered. What's also clear is that many of the stated reasons in EIA documents that make economic assessments don't take into consideration the opposition from anti-nuclear forces back at that time. That opposition's primary effect was delayed construction, meaning that interest drained the coffers of those on the hook for it.
A document that's been available on this site for some time is an AEC internally written history of the early years of the anti-nuclear movement up to mid-1973. It's essential reading for those who have seen Pandora's Promise and want a better view of what was really going on. It's quite eye opening. The document can be found by clicking this link; however, it's also available in the right side bar. See "Public Attitudes Toward Nuclear Energy - WASH-1250."
On Tuesday, President Obama is now known to be making a speech about energy policy and climate change. The whitehouse.gov video hints that he'll mention new biofuels, and new technologies. One wonders if the hiring of a former Union of Concerned Scientists executive at a high level in the Department of Energy isn't part of a broader administration signal that nuclear energy will be left out. Indeed, it's instructive today (considering environmental panic of the moment) to look back at the Charlestown RI "NEP" project -- and see that part of the justification for cancelling it was "conservation." That's right -- that means forcing people to make do with less, instead of generating more power cleanly.
We might be coming to a serious junction in this country in terms of energy policy. It's important to see that nuclear energy must play a role in our energy future - it provides relatively fixed-cost, reliable energy around the clock with no exhaust. No GHG; no soot. Further, manufacturers of SMR (Small Modular Reactor) plants are planning to replace coal fired units nearer to cities than large nuclear plants can be built with small, underground, inherently safe nuclear units that bring lowered purchasing and operating cost along with 24/7 power capability to the table. These units will even be able to load follow -- allowing for more renewables to be used on the same grid.
Let's select the direction we want to go, this time around -- and get there. Let's not allow under-construction and planned nuclear stations to get waylaid. Instead, let's embrace the reasons why we need nuclear energy (safe, efficient, round the clock power) and the reasons we might want to avoid fossil fuel (greenhouse gas emissions) and have the courage to take a path and plow toward a goal. And, let's not leave a trail of incomplete gravestones to our ideals this time around. I've seen enough of the illustrations such as I've showed you today -- nuclear plants planned and ordered but never built.
2:00 PM Eastern 6/23/2013
£10 Billion Guarantee for Hinkley Point C in UK
SCE begins job elimination process at SONGS
Obama's Climate Action Plan
SCE notifies NRC that San Onofre Nuclear Generatin...
FLASH: SAN ONOFRE NUCLEAR GENERATING STATION TO B...

redpajama_set_name: RedPajamaCommonCrawl


Mika King of the MegaCon Boxes!
Mika says, "Mom was busy with MegaCon all last week. Just look at these boxes everywhere! These were stacked like stairs so I'm The King of the Boxes!" FYI for everyone that's new to following Anakin, Mika & The Gang.... I'm Carrie Hawks, Ani's Mom & I'm a Fantasy Cat Artist https://Tigerpixie.com I've included a pic of my MegaCon booth set up in the next pic. This was a great show for me! My best MegaCon yet! I definitely plan on being back next year.


The main character can change genders, but for the most part, he remains a male.
is what normal human beings would call perfect, in my opinion.
I told people a few times but I guess it was forgotten when it was added to the update.
I wanted to do it because I really liked that chapter.
I have actually translated the first volume entirely and am working on the 2nd and 3rd ones in my freetime if someone wants to help with setting the text and the other stuff visit detcetorp and maybe you can help me with it.
the first story is about a young couple eloping, that are in a tragic bus accident. a mysterious boy saves them, allowing the couple to live another 60 years.
i really liked this oneshot i wonder why the series was never continued.
but i cant help but wonder if the boy really saved them, or was it a realm between life and death?


text:
Friends of Music at MSU Denver
Friends of Music at MSU Denver is a community that invests and partners with The Department of Music to ensure that we continue to enlighten, inspire, and transform the lives of our students and the Colorado community of the arts. Generous contributions from the Friends of Music at MSU Denver have helped nearly replace $70,000 in student scholarship funding that is no longer provided annually by the State of Colorado. By becoming a Friend of Music at MSU Denver, you directly impact the success of our students through vital scholarship funding, on which so many rely.
Opportunities for Impact
Friends of Music at MSU Denver: Annual Fund
The annual fund of Music at MSU Denver is supported by direct contributions of supporters, funds generated from ticket sales for concerts, an annual gala concert and silent auction, and generous support from the Provost. The scholarships are given to students in the form of talent awards based on their contributions to the major ensembles in their area of study. All funds generated each year are awarded.
Friends of Music at MSU Denver: Endowments
Endowments are substantial investments that earn scholarship money each year indefinitely. Over the past few years, we are pleased that we have partnered with generous individuals and foundations to create a new endowment nearly every year. While the list of endowments is not yet complete, you may feel drawn to support a particular area or make a gift to commemorate the impact that an individual had on your life. Our students thank you in advance for your generosity.
Christopher Priolo Endowment
For Excellence in Composition
Jerrald D. McCollum Endowment
For Outstanding Potential as Music Educators
William Morse Endowment
For Outstanding Instrumentalists in the MSU Denver Orchestra
Beverly Fernald Endowment
For Excellence in Voice Performance
Frank G. Edmonson Endowment
Demonstrated talent and significant interest in the guitar and/or willingness to contribute to the department in the area of sound engineering
The Band Excellence Award
Based on a strong commitment to the band program through musicianship, dependability, loyalty and cooperation.
The Larry Worster Endowment
A General Endowment: For academic and personal excellence in any area. Awardees shall not have received another named or endowed award.
Become a Friend today!
All donors receive the Friends of Music at MSU Denver newsletter, Metro Magazine, and recognition in Department of Music concert programs. Your gift will be designated according to:
Supporters - $1-$99
Patrons - $100-$499
Benefactors - $500-$999
Visionaries - $1,000-$4,999
Legacy Circle - $5,000 or more
A donation of over $1000 entitles the donor to membership in the President's Society, while a donation of over $25,000 entitles the donor to create an endowed Department of Music scholarship.
MSU Denver Faculty and Staff may donate via the Faculty/Staff Gift Form.
All contributions are tax deductible to the extent allowed by law.
Join Friends of Music at MSU Denver
Music Degrees
Program Admission
Music Students


Today, since this post is late, I'm just going to find random pictures on my computer to post. I'll try to get ones that have not been posted yet, or ones that have not been posted for a long time. Don't forget to click on the pictures to get a larger picture and more detail about the picture.
Useless Knowledge: Lucille Ball, from I Love Lucy, was tossed out of drama school in New York when she was only 15 years old.The reason? Her instructors claimed that the future madcap comedienne was too quiet and shy.
1 Jul – Hits @ 0140 = 600333 which equals to 4509 hits in five minutes less than 24 hours.
There's not much happening today, but that doesn't mean I don't have anything to say. I'm going to discuss some of the searches people have been doing and let y'all in on somethings that you can expect to see in future posts. Please ignore the Harmful Site thing that F-Secure has marked for the Affiliates. The sites are not harmful, at least none of the ones I listed because I've been to them all and nothing has happen to my computer.
Cousin Neneng with her baby.
Someone from Manila did a search for "safety procedures in driving in the Philippines". No surprisingly, as far as I'm concerned, my website was the only one that came up and then only because of the one article that had the words "safety" and "drive" in it. Safety procedures for driving in the Philippines are virtually non-existent. They have over loaded vehicles, passing on the road anywhere (on bridges and no passing zones) and on the wrong side, people and animals all over the street, speeders, no real stops signs in most places, no head lights at night usually … you get the picture. It's a mess.
Useless Knowledge: It's difficult to drown an ant because water doesn't penetrate their minuscule breathing tube; they will suffer, however, from too much carbon dioxide, which knocks them out. It takes awhile, but they will eventually die.
I've decided to check the most viewed posts and do a follow up or continuing story on each one of the top 10. I've already posted an additional story for the #1 viewed post on Germany announcing Hitler being dead. I never figured that one would be the #1 viewed post, but it has been. Maybe the follow-up story will be just as popular. I don't want to do too many stories that are not Philippines related, so don't be expecting too many stories like this. If this wasn't the #1 story, I would not have posted a follow up story at all. The top 6 views after this one are all Philippines related. You can expect to see updates or additional information on several others in the coming days and weeks.
Someone from Paranaque Rizal (Philippines) was looking for "American retirees living in the Philippines". They got the Philippines Retire Story, but I hope they realized that …. oh this post is going to be late. I really need to go to sleep. I've been making a numerous amount of errors. I'll continue tomorrow.
Okay maybe I should have changed the errors in the last paragraph, but that is how I type when I have had too much to drink and on top of that, falling asleep at the computer. You can see the sentence started out okay, but by the time I got to the end of it, the "teh", I was losing it. So now you know why the post is late. But I'll probably just do the normal one tonight and be all caught up again. I seriously do not even remember typing those last 3 sentences above. After the word "late", it's all blank.
Alright, let's start this again. Someone got the Philippines Retirement Story when they looked for American retirees in the Philippines. I hope that who ever it was realized that on the front page of the website there are many links to expat websites. It doesn't look like they explored much further than that, but maybe they came back in later, I hope so.
Lita has just informed me that if I'm going to make soup today, I need to do it early. They will be using the propane around 1:00pm. Later today we will be getting the new propane tank for the other stove, so this problem will be over with for awhile.
Lita and I did go downtown today. I remembered the camera, but unfortunately when I remember it we were already a quarter of a mile down the road. We went to the bank to get some money and the line was short, only 2 people in front of me and someone inside. Okay, cool. Not! The person inside didn't take very long, but the next lady in line was slow, very slow. Fay, our 3 year old here, could have been in and out of there faster. I finally see her coming out, but she just has a question for the security guard and she went right back in. Finally, after about a total of 15 minutes (no kidding), she comes out. The next person gets up to go in and the security guard stops her and tells her that they have to refill the ATM. Of course they don't have the ones like in the US, the ones that fill from the back. They have to fill from the front. The guard locked the access door and we waited. We waited like another 10 minutes. When the lady in front of us went she took another 10 minutes (just kidding)…she was pretty quick. But still it took me about 1/2 an hour for 4 people on an ATM. I've been through lines there that were 3 times that long that didn't take that much time.
When we finally got the money, I only took P10,000, I went ahead and paid the Internet and complained about the slowness of my connection sometimes, recently. The guy said he would fill out a work order for me and let them know. I hope to have someone show up within the next few days.
We also stopped by Mercury Drug to pick up a few essentials. Things like mouthwash, deodorant and Doritos. Well they had taco flavored Doritos and I didn't want to take a chance that they would run out. It not something they have all the time. They are my favorite Doritos and actually my favorite chip, so yes they were essential.
I will go back downtown tomorrow to get more money and pay the rest of the bills. We still plan to go to Tacloban, but it may be delayed until the end of the month or even the beginning of August. It's always getting delayed, but the necessities come before the desires. I'll sure be glad when the few payments we do have, are done. I see why they say it takes about 5 years to get fully adjusted to living in the Philippines. I still think we can do it in 3 years though.
Useless Knowledge: In every single episode of TV's Seinfeld, there is a Superman somewhere in at least one scene.
1898 – Apolinario Mabini y Maranan, chief adviser of Dictator Emilio Aguinaldo, requests permission to proceed to Manila to persuade Spanish Governor-General Basilio Agustin to surrender to the Filipinos during the second phase of the Philippine Revolution against colonial Spain and three weeks after Aguinaldo declared the Independence of the Southeast Asian archipelago; exactly two years later, on July 1, 1900, Aguinaldo's decree providing that the highest authority in the Catholic Church in the Philippines be the Military Vicar General recognized by the President of the Philippine Republic becomes effective, thus regulating the exercise of ecclesisastical jurisdiction by Catholic religious people.
Hi JJ! Well I'm back, but of course you didn't even know I went away. 🙂 And here I am trying to catch up with your – and Lita's- world and I don't know how to navigate your blog anymore! 🙁 I wanted to start with the 1st of July blog and work myself up to the present. What happened to the calendar that was so handy? It's a real BEACH to read your blog in an orderly, chronological fashion.
OK, I'll struggle looking for July 3rd and in the process of stumbling around rack up more hits on your site 🙂 Oops. i just saw the "next post" link that you've hidden so well.
C u later. Holy cow, now I can't post without answering a secury Q?
Hi Winda .. I just figured you didn't have anything to say, so you were just reading. I didn't realize it was that hard to following the blog when/if you get behind. I'll see what I can do.
Sorry about the 'easy' security question, but I was getting so much spam and I was getting tired of deleting it every 10 minutes. Since I've started that, about 2 weeks ago, I have had 0 spam messages.
Looking forward to 'maybe' hearing about your absence.
I got to July 6th before I had to leave again. I'll make this short so I can go and read some more.
Well I put your calendar back, so I hope that helps you.
Just get a calculator, like Jake said he has to use.
Y'all are silly, and I love it.


1 Dallis Bros. Coffee Unisphere Blend $12.00 / 12 oz.
2 JBC Coffee Roasters Kivu Dr Congo $16.90 / 12 oz.
4 Thanksgiving Coffee Byron's Maracaturra Natural $16.50 / 12 oz.
5 Kuma Coffee Ethiopia Guji Natural $19.00 / 12 oz.
6 Passion House Coffee AME Mix $30.00 / 24 oz.
7 Ritual Coffee Gakoma, Rwanda $20.25 / 12 oz.
8 Thanksgiving Coffee Bolivia Canto de Bolivar Organic $15.50 / 12 oz.
9 Thanksgiving Coffee Kenya Nyeri Peaberry $19.00 / 12 oz.
10 PT's Coffee Colombia Finca Villa Loyola $19.50 / 12 oz.
11 Onyx Coffee Lab Colombia Aponte Village $16.50 / 12 oz.
12 Thanksgiving Coffee Colombian Blend $13.50 / 12 oz.
13 Thanksgiving Coffee Ethiopia Gedeb Yirgacheffe $17.00 / 12 oz.
14 Barefoot Coffee The Tango $44.75 / 2.5 lbs.
15 Thanksgiving Coffee Ethiopia Hambela Farm $17.00 / 12 oz.
16 Thanksgiving Coffee Ethiopia Natural Yirgacheffe Halo Bariti $16.50 / 12 oz.
17 Thanksgiving Coffee Peru Miel de Cajamarca Organic $15.50 / 12 oz.
18 Onyx Coffee Lab Colombia La Palma Soccoro Pico $22.00 / 12 oz.
19 Passion House Coffee Chicago House Blend $14.00 / 12 oz.
20 Barefoot Coffee The Tango $17.50 / 12 oz.
21 Onyx Coffee Lab Kenya Gichathaini OT-18 $100.00 / 5 lbs.


text:
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Google and hypocrisy
Google and copyright... don't get me started!
Apparently, Google is lobbying the NZ government to make some changes to our copyright laws, urging a "more flexible and forward-looking approach".
The search-engine giant claims that such changes are an important element of its advanced AI research and innovation.
Now I strongly believe that everyone, including multinational corporations which pay their fair share of tax to our government, has a right to lobby and plead their case for legislative change.
The question is however: does Google really qualify, given its profit-shifting and ability to dodge tax liabilities?
I also find it hugely hypocritical that Google is pitching for "fair use type provisions" within our copyright laws -- when it effectively denies the same to all those who create content for its YouTube service.
Let's face it, Google has built its fortunes on leveraging other people's content for profit. Without other people's content to make "fair use" of, there would be no Google Search, Google News, Google Books or a raft of their other services.
To be honest, I'm in favour of fair-use, so long as it is *fair*.
Sadly, Google's interpretation of "fair" and that of those who produce content are not always congruent, something which suggests that Google's understanding of "fair" translates to something more like "in our favour".
As a result of this mismatch of interpretations, Paula Browning CEO of Copyright Licensing NZ has been quoted in Stuff story as expressing a belief that copyright laws are not holding back innovation and she roundly criticises Google's assertions.
I would suggest that if our politicians have any backbone, they will close the door to Google's lobbyists until such time as they accept their responsibility to pay a fair share of tax by ditching the profit-shifting that is currently being used as a tax avoidance mechanism. Let them see that although they may be able to legally avoid paying their way, there are downsides to doing so.
Sadly however, I fear that we'll see yet another bunch of politicians who fawn all over the utterances of lobbyists from yet another huge multinational and sway to the breeze of their demands.
Personally, I expect we can smell the uranium on their breaths.
Google can no longer claim that it isn't evil (they removed that mantra some time ago) so we should therefore assume they are.
If Google wants to change copyright law for the better then I suggest that they start at home and lobby the US government to ditch its propensity to just keep on extending the term of protection offered by its copyright laws (every time the copyright on a piece of Disney's intellectual property is due to fall into the public domain).
Here in New Zealand, our copyright laws may be far from perfect -- but they're still a snot-load better than the ones in Google's home-country so get your own damned house in order first before you start telling us how to run ours.
And stop being so hypocritical. If "fair use" is essential then allow your YouTube content creators to take advantage of it without risking a copyright strike.
What do readers think? Will our politicians ask "how high" when Google asks them to jump? Should we deny them lobbying rights until they agree to stop profit-shifting and thereby avoiding their fair share of corporate tax in this country?
Oh, and my apologies for skipping yesterday's daily dose... I had to travel to Auckland for a funeral which meant a *very* long day.
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New Zealand has been talking about the idea for some time but the French seem to have been the first to make a move...
Robomaster has arrived
I'm a great fan of STEM, STEAM and other programs to get kids interested and involved in technology and so I was thrilled to see the latest product from DJI (the drone people)...
Assange, another vendetta?
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Likable rogue... or villainous pirate?...
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Fascism (/ˈfæʃɪzəm/) a governmental system led by a dictator having complete power, forcibly suppressing...
Facebook Tax - the end of free trade?
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E3 2017, Microsoft — 4K, Innovative, Immersive, Other Buzzwords
Published on June 28, 2017 October 4, 2018 by Button PanelsLeave a comment
Again, apologies for the amazing lateness (I'm like two weeks late on this!). Stuff comes up, comics needed to be read, Mr. Robot episodes needed to be watched. Anyway, here are my thoughts on Microsoft's 2017 E3 conference. Minor releases and the like are at the bottom. Continue reading "E3 2017, Microsoft — 4K, Innovative, Immersive, Other Buzzwords" →
Categories e3, Preview Thoughts, Uncategorized•Tags 4a games, annapuma interactive, annapurna interactive, anthem, anthem game, arc system works, ashen, ashen game, assassin's creed, assassin's creed origins, aurora 44, backwards compatibility, bandai namco entertainment, bandai namco studios, beethoven & dinosaur, beethoven and dinosaur, before the storm, bioware, black desert, black desert online, bluehole, cloudgine, code vein, coffee stain studios, crackdown, crackdown 3, cuphead, deck nine games, deep rock galactic, deep silver, dragon ball, dragon ball figher z, dragon ball figherz, dragon ball z, e3, e3 2017, ea, ea games, electronic arts, forza, forza motorsport 7, fullbright, games, games industry, gaming, kakao games, life is strange, life is strange: before the storm, lucky's tale, metro, metro exodus, microsoft, microsoft studios, middle-earth: shadow of war, minecraft, mojang, monolith productions, moon studios, odd tales, ori and the will of the wisps, Pc games, PC Gaming, pearl abyss, playerunknown's battlegrounds, playful, rare, raw fury games, reagent games, ruffian games, scorpio, sea of thieves, shadow of war, sony computer entertainment, square-enix, state of decay, state of decay 2, studiomdhr entertainment, sumo digital, super duper texture pack, super lucky's tale, tacoma, the artful escape, the last night, turn 10 studios, ubisoft, ubisoft montreal, undead labs, video games, video games industry, warner bros. interactive entertainment, xbone, xbonex, xbox, xbox one, xbox one x
E3 2016, Microsoft – Surprising, But Not Very
Published on June 29, 2016 July 4, 2016 by Button PanelsLeave a comment
Now this one was really uneven. On one hand, it has a lot of the typical PR stuff like bringing on people to talk up your stuff, so that's a strike against it. It felt very typical… but had some genuinely nice and surprising announcements!
Continue reading "E3 2016, Microsoft – Surprising, But Not Very" →
Categories e3, Preview Thoughts, Rantings, Uncategorized•Tags 343 industries, 343i, armature studio, bandai namco studios, capcom, capcom vancouver, comcept, compulsion games, creative assembly, dead rising 4, ff15, ffxv, final fantasy, final fantasy xv, forza horizon, forza horizon 3, gears of war, gears of war 4, halo, halo wars, halo wars 2, inside, minecraft, mojang, PC Gaming, platinumgames, playdead, playground games, project scorpio, rare, recore, scalebound, sea of thieves, state of decay, state of decay 2, street fighter, tekken, tekken 7, the coalition, the division, ubisoft, undead labs, we happy few, windows 10, xbox, xbox one, xbox one s


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A multimethod paleointensity approach applied to the historical Xitle lava flows (Central Mexico): towards the accurate paleointensity determination
Juan Morales ORCID: orcid.org/0000-0001-7824-04911,
Nayeli Pérez-Rodríguez ORCID: orcid.org/0000-0002-7231-75982,
Avto Goguitchaichvili1 &
Miguel Cervantes-Solano3
An inclusive rock-magnetic and absolute paleointensity survey of the ~ 2-ka-old Xitle volcano (southerly Basin of Mexico) was undertaken to assess the faithfulness of the paleomagnetic log carried by fresh, widely exposed and well-preserved lava flows. Paleomagnetic samples from six lava flows were subjected to paleointensity analysis with a multi-method approach: the Thellier–Coe, IZZI, and multi-specimen methods. Overall mean flow PI values from flows 4–6 obtained by the Thellier-type methods used yielded 68.4 µT (σ = ± 5.6 µT), 63.9 µT (σ = ± 5.8 µT) and 61.5 µT (σ = ± 4.3 µT) for the TC, IZZI, and IZZI with CR correction methods, respectively. Although multi-specimen paleointensity results were, in general, lower than that obtained with the other methods for the same flows, that for Flow 5 (61.8 µT) was very similar to those obtained with the Thellier-type methods. Based on the results obtained, this lava flows sequence could correspond to two eruptive periods; one related with the Xitle volcano (flows 3–6), and another older (flows 1 and 2). The combined archeomagnetic dating of the different flows reinforces this hypothesis, as well as the multi-modal distribution for the age of the Xitle, proposed two decades ago. The application of stricter acceptance criteria and consideration of cooling-rate correction could slightly reduce the scattered observations. The multi-method approach employed under this study, combined with detailed rock-magnetic experiments, may definitively increase the accuracy of paleointensity determinations.
The Xitle volcano belongs to the Chichinautzin Quaternary volcanic field. It is located south of the Valley of Mexico (Herrero-Bervera et al. 1986; Urrutia-Fucugauchi and Martin-del Pozzo 1993). It is a monogenetic cone whose lavas overlay an area of approximately 80 km2 in which seven flow-units are identified (Fig. 1; Delgado-Granados et al. 1998). The largest flow to the north is more than 13 km long, encompassing an area of 70 km2 (Martin-del Pozzo et al. 1997; Delgado-Granados et al. 1998) and covering the first urban settlements of the Valley of Mexico (Heizer and Bennyhoff 1958)—the archeological center of Cuicuilco.
(modified from Delgado-Granados et al. 1998)
Location map of Xitle volcano and the spatial distribution of its different lava flows
Being one of the youngest volcanoes, charred material (charcoal from pottery level below lava) by its eruption was used during the development of the innovative radiocarbon method for dating organic materials (Arnold and Libby 1951; Libby 1955), obtaining a date of 2422 ± 250 years BP. After this, more than 30 further studies have been reported, yielding a breadth age interval for the Xitle's eruption. Through a comprehensive review of the available radiometric dates, Urrutia-Fucugauchi (1996) identified three apparent clusters roughly around 4000, 2375, and 2000 years BP. The older cluster is mainly associated with the early archeological occupation Tlalpan stages (Fergusson and Libby 1963), while the other two to the age for the Xitle eruption, respectively. Moreover, an age of 1670 years BP was proposed (Siebe 2000).
Likewise, its different lavas have aided to appraise the reliableness of the paleomagnetic log carried by fresh, widely exposed and well-preserved lava flows (Urrutia-Fucugauchi 1996). In the case of paleointensity (PI) determinations, it seems to be also a matter of controversy. Pioneer estimations of Nagata et al. (1965a) yielded a mean PI value of 56.11 ± 5.89 μT (n = 8), while those of González-Huesca (1992), Morales-Contreras (1995) and Urrutia-Fucugauchi (1996) yielded mean PI values of 66.83 ± 10.09 μT (n = 6), 59.2 ± 11.0 (n = 9) and 60.04 ± 9.62 μT (n = 6), respectively. It is worth mentioning that all these studies were carried out on sites from different flows of the Xitle volcano.
Moreover, variations in the PI values are observed across vertical sections within a single flow (e.g., Urrutia-Fucugauchi 1996; Böhnel et al. 1997; Alva-Valdivia 2005; Morales et al. 2006). Given its monogenetic nature and considering that recent historical eruptions of similar volcanoes in the Mexican volcanic belt point to brief activity periods, around a decade or so (e.g., Paricutin 1943–1953 or the 1759–1774 Jorullo eruptions; Bullard 1976) no such PI differences should be obtained. Attempts to correlate the observed PI variation to rock-magnetic properties, different oxidation states, etc., have not been able to account for these inter-flow variations.
The refinement of PI methods and the proposal of stricter acceptance criteria have arisen with time, as well as new PI methods, which could contribute to a better understanding of the causes for such variations. Even more, multi-method approaches have been recently applied to the study of volcanic rock (e.g., Calvo-Rathert et al. 2016 and Calvo-Rathert et al. 2019) as an alternative criterion of reliability.
In the present study, we report the paleointensity results from six different lava effusion episodes from unit V of the Xitle volcano obtained with the multi-specimens and IZZI methods, considering also cooling rate correction. Likewise, we carried out a reassessment of the Thellier–Coe paleointensity results previously reported on sister samples using stricter acceptance criteria.
Material and rock-magnetic results from the previous study
The paleomagnetic sampling of lava flows was done previously and results were reported by Cervantes-Solano et al. (2019). Sampling was completed at the Ciudad Universitaria Basaltic Lava member (BCU), at the site known as La Cantera (19° 18′ 47.10″ N, 99° 10′ 19.01″ W)—a quarry at the neighborhood of the UNAM facilities (Fig. 1). At this site is the most complete exposure of lava flows with a thickness of 40 m, which corresponds to the unit V described by Delgado-Granados et al. (1998), in which seven individual lava units with thicknesses of 2 to 8 m each are distinguished (Fig. 2). Lava-flow sampling was realized using a hand-held water-cooled gasoline-powered drilling device with a diamond bit; all samples were oriented using a precision core orienting accessory with a magnetic compass mounted on it. Fifty-four standard paleomagnetic cores (8 to 10 samples per flow) were obtained from the exposed-interiors of six flows, which were consecutively numbered according to their stratigraphic position (i.e., 95X001AL–95X054L; L: A, B or C, the outermost specimen, the one at the middle, or the innermost specimen), with Flow 1 the one at the bottom and Flow 6 the one at the top of the exposure. Because of its inaccessibility, Flow 7 was unable to be sampled.
(adopted from Alva-Valdivia 2005). Left: a closer view of the paleomagnetic sampling
Right: view of the 7 flows exposed at BCU quarry
Thermomagnetic curves indicate the existence of a magnetic phase during heating with Curie temperature between 520 °C and 560 °C, suggesting magnetite or titanomagnetite with low titanium content as responsible for the magnetization. Cooling curves are similar to heating ones, showing a decrease in initial susceptibility less than 15%, which is likely due to oxidation produced during heating (Fig. 3). For details of the opaque mineralogy, the reader is referred to the paper by Alva-Valdivia (2005).
Representative thermomagnetic (κ-T) curves for the different flows analyzed, obtained in the previous study (Cervantes-Solano et al. 2019). Curves in red correspond to the heating, while those in blue to the cooling
In most samples studied (60%), two magnetization components are observed, the first of which is removed during the first steps of demagnetization (fields from 5 mT to 10 mT) and represents less than 10% of the value of the total magnetization of the samples and is likely to be of viscous origin. Once this component was removed, the behavior was linear towards the origin in the orthogonal Zijderveld (1967) diagrams. Another group of samples (31%), corresponding to flows 2 and 5, retain about 40 to 50% of the initial magnetization after having applied magnetic fields of 90 mT, however, a linear behavior towards the origin of coordinates is also observed. In the remaining 9% of samples, a single stable component was identified with a single behavior towards the origin.
Paleointensity experiments were carried out on six to seven specimens per flow (40 in total) using the Thellier double-heating method (Thellier and Thellier 1959) as modified by Coe (Coe 1967), here thereafter called Thellier–Coe (TC). Heating and cooling were done in a TD48 thermal demagnetizer from ASC Scientific. Once the specimens reached the desired temperature at each heating step, they were left for an idle of 20 min at that temperature so that all specimens got thermal equilibrium. Afterward, the fan was turned on permitting the samples to cool down. The laboratory field (45.0 ± 0.5 µT) remained on for infield steps during the whole heating–cooling cycle. Thirteen temperature steps were distributed between room temperature and 580 °C, and pTRM checks were carried out at every third heating step, except at the last one. Natural and laboratory-induced remanent magnetizations were both measured through a JR6 dual-speed spinner magnetometer from AGICO.
Experimental procedure
The experiments were performed with material left from the former study (Cervantes-Solano et al. 2019), and the original numbers of the specimens were preserved, but for the sake of simplicity, the initial number (95) in the specimen's ID was eliminated. This enabled us to analyze sister samples, minimizing the possibility of within-flow heterogeneities, as well as the application of a multi-methodological exercise on almost the same material.
Rock-magnetic experiments
Stepwise low-field susceptibility (κ-T) curves were obtained for precise monitoring of the onset of the magneto-chemical alteration of the magnetic mineralogy. This monitoring was done using an MFK1B Kappabridge from AGICO in an argon atmosphere. A four-step procedure, initiating at 100 °C and with an opening return-temperature of 350 °C, was followed up to a maximum final temperature of 500 °C. Temperature increments of 50 °C were set for the following return-temperatures (i.e., 350, 400, 450, and 500 °C).
Paleointensity determinations
Absolute paleointensity determinations were accomplished employing two different methodologies. The first set of paleointensity experiments was performed with the multi-specimen (MS) technique proposed by Hoffman et al. (1989) as modified by Dekkers and Böhnel (2006). Protocols for fraction correction (FC) and domain-state correction (DSC)—proposed by Fabian and Leonhardt (2010)—were also included. Three different standard paleomagnetic cores per flow were used for these experiments. Each standard paleomagnetic core was cut into eight specimens, which were pressed into standard-dimension cylindrical salt pellets and labeled from 1 to 8 (e.g., X001-C-1–X001-C-8), obtaining 144 specimens. The multi-specimen method was carried out at a temperature of 450 °C—a temperature below the lowermost Curie temperature observed from κ-T curves but enough to create a pTRM. Experiments were performed using a TD48-SC furnace (ASC Scientific) with laboratory fields varying from 10 to 70 μT, and increments of 10 μT. The following measurement sequence was applied to the specimens subjected this methodology: (i) the natural remanent magnetization (NRM) of the different specimens were measured; (ii) six specimens were oriented so that their corresponding NRM directions lay parallel to the axis of the heating compartment and heated at 450 °C using the first laboratory field selected (10 μT). After cooled down, their remanences were measured; (iii) specimens were set and heated as in the previous step but inverting the laboratory field direction. Then, their remanences were measured; (iv) specimens were reheated in zero field and cooled infield, and their remanences measured; (v) Step (ii) was repeated. Once finished this five-step procedure, another set of six specimens was worked, using the next laboratory field (20 μT) up to 70 μT.
All calculations (relative differences between pTRMs and NRMs) and corresponding correction factors were accomplished following Fabian and Leonhardt (2010).
The so-called 'IZZI' method (Tauxe and Staudigel 2004; Yu et al. 2004) was employed for the second set of paleointensity experiments, using one or two standard paleomagnetic cores per flow, which were previously cut, pressed into salt pellets and numbered consecutively (e.g., X014C-1–X014C-4). 32 specimens were treated using the following measurement sequence: (i) The NRM of the specimens was measured. (ii) The specimens were heated to temperature T1 in a close to zero (~ 50 nT) magnetic field strength and then their remanences were measured. (iii) The specimens were heated again to temperature T1, but this time in the presence of a magnetic field (50.0 ± 0.5 µT), and then their remanences were measured. (iv) The next heating step is performed at a temperature T2 (with T1 < T2) in the presence of a magnetic field. (v) The T2 temperature step is repeated in the absence of a magnetic field. (vi) The temperature is increased further to a T3 value, the samples were heated in the absence of a magnetic field. (vii) A pTRM check is performed from T3 to T1. (viii) The specimens are then reheated to T3 in the presence of a magnetic field. (ix) A pTRM tail check is performed. (x) Steps (iv) to (ix) were repeated as often as necessary to cover the entire Curie temperature range of the ferromagnetic minerals present in specimens under analysis.
Although cooling rate (CR) effects on volcanic rocks are not normally considered in most paleointensity experiments (Morales et al. 2006), we have decided to consider it at the end of this experiment. Cooling rate dependence on TRMs was studied using a modified procedure to the one outlined by Chauvin et al. (2000) (e.g., Morales et al. 2006). Finally, to account for non‐ideal multidomain (MD) behavior, the curvature k of the individual Arai plots was estimated.
k-T curves
Stepwise low-field susceptibility vs temperature (κ-T) curves helped to evidence the temperature range at which mineral alteration took place. In the cases of Flow 1 and Flow 3, evident magneto-chemical alteration seems to start at moderate temperatures, between 350 and 400 °C (Fig. 4). On the contrary, alteration appears to start at higher temperatures (400 °C and 450 °C) in the case of Flow 6. The analysis of the susceptibility curves was accomplished using the Cureval 8.0.2 software (Chadima and Hrouda 2012).
Representative stepwise thermomagnetic (κ-T) curves for the different flows analyzed, obtained in this study. Peak heating steps used: 350, 400, 450, and 500 °C. Curves in red correspond to the heating, while those in blue to the cooling
Reassessment of the Thellier–Coe results from the previous study
Different factors play significant roles in the reliability of a paleointensity determination—quality of the experimental conditions, the occurrence of alteration, and the presence of remanent magnetization carried by MD grains (Calvo-Rathert et al. 2016). On the other hand, several statistical parameters and different reliability criteria for paleointensity determinations have been proposed to take into account for these experimental situations (e.g., Selkin and Tauxe 2000; Kissel and Laj 2004), however, no specific criteria and parameter set is normally applied (Calvo-Rathert et al. 2016).
Accordingly, we carried out a reassessment of the Thellier–Coe paleointensity results previously reported by Cervantes-Solano et al. (2019) on sister samples using the same stricter acceptance criteria used for the results obtained in this multi-methodological exercise.
Acceptance criteria of different strictness (A, B, or C, as proposed by Leonhardt et al. 2004) were employed to label successful paleointensity determinations according to specific quality levels, which are summarized in Table 1.
Table 1 Selection criteria and threshold values for the three determination classes (A, B, and C) for Thellier–Coe experiments
Additionally, concave-up shape Arai plots are rejected for the PI calculations because, in such cases, the remanence is very likely carried by MD grains (Levi 1977). Its contribution was assessed estimating the curvature k of the selected data points of the Arai plot (Paterson 2011). Following Paterson (2011), threshold values for k = 0.164 and k ≤ 0.270, defined using samples with known grain sizes, were used. The curvature k was determined in MATLAB using the function CircleFitByPratt (XY) (Chernov 2019) which uses the method proposed by Pratt (1987) for fitting a circle to a set of data points on a plane. Estimation of paleointensity values was performed using the ThellierTool4.0 software (Leonhardt et al. 2004).
Based on the above-mentioned criteria, no reliable paleointensity determinations could be gathered from flows 1 and 2, except for one specimen from Flow 1 (X004A).
Most specimens showed very scattered Arai plots and negative pTRM checks even at low temperatures. Given the negative pTRM checks and the irreversible κ-T behavior of the curves obtained on sister samples, this misbehavior could be attributed to significant thermochemical alteration during the paleointensity experiments. On the contrary, although with a very low success-rate, reliable PI determinations were obtained from flows 3 to 6. A representative Arai plot (Nagata et al. 1965b) is shown in Fig. 5a.
a Representative Arai plot (Nagata et al. 1965b) obtained from the TC experiments. b Representative plot obtained from the MS experiments. c Representative Arai plot (Nagata et al. 1965b) obtained from the IZZI CRcorr experiments
It is observed that flows 4 and 6 yielded slightly similar PI of 66.0 ± 5.5 µT (n = 3) and 72.8 ± 3 µT (n = 3), respectively. For flows 3 and 5, however, only one specimen per flow yielded an acceptable result, 86.2 ± 4.0 µT, and 62.4 ± 3.1 µT, respectively. Results are summarized in Table 2 and are graphically presented in Fig. 6.
Table 2 Thellier–Coe paleointensity results for all six studied flows. Tmin/Tmax: lower/upper temperature step used to determine the archeointensity
Comparison of PI results obtained by the different methodologies used (TC, IZZI CRcorr, and MS) for the 6 flows analyzed. Error bars represent the corresponding standard deviations in the case of TC and IZZI CRcorr results, while for the MS data to the Min and Max values obtained
This means that only 8 out of the 40 previously reported results (20%) can be considered as reliable. If the curvature parameter is also considered, only five results survive (12.5%).
Representative Arai (Nagata et al. 1965b) and associated vectorial (Zijderveld 1967) plots for the six flows analyzed are shown as Additional file 1: Figure S1.
Multi-specimen method
As above-mentioned, two magnetization components were observed in almost 60% of the samples studied. These soft overprints were also observed at the vectorial plots obtained from the Thellier-type double-heating method, which were eliminated at temperatures between 200 and 350 °C. Thus, the chosen heating temperature of 450 °C seems to be suitable to remove these overprints on the one hand and locates somewhat below the Curie temperature observed from M-T curves on the other hand, so that thermochemical alteration on the specimens due to heating should be less likely. Calculations were performed through the VBA software of Monster et al. (2015a).
Reliability criteria applied for this methodology was based on: (i) a maximum acceptable angular deviation (AAD) of 10°; (ii) the "overprint?" check and (Δdec and Δinc) < 10°; (iii) the amount of progressive alteration (εalt) ≤ 10%; (iv) the intersection with the y-axis (Δb = −1 at Hlab = 0), and (v) the linear least-squares fit (R2).
All PI determinations fulfill with the criterion of δb between (0, 1) and show r2 values ≥ 0.9, except one case (Flow 5). However, despite the low enough chosen heating temperature of 450 °C, Avg εalt range between 6 and 12%. In general, the original DBc, fraction, and domain-state-corrected determinations with alignment correction (FCc and DSCc, respectively) yield higher R2 values than the corresponding uncorrected values.
Flow 1 yielded a significantly lower mean PI value (21.6 µT; min = 17.9 µT, max = 23.8 µT), compared with those obtained from the other flows, and no significant differences between the results of the original DBc and the extended protocols FCc and DSCc are observed. Flow 2 and Flow 4 yielded undistinguishable PI values of 52.9 µT and 49.5 µT, while Flow 3 and Flow 5 PI values of 58.2 µT and 61.8 µT, respectively. In the case of Flow 6, a PI value of 51.9 µT was obtained, although with a higher Avg. εalt of − 17.6%. A summary of the results is provided in Table 3, and a representative plot is shown in Fig. 5b. Plots for the six flows analyzed are shown as Additional file 1: Figure S2.
Table 3 Multi-specimen (QDSC) paleointensity results for the different flows studied. Min and Max: estimated minimum and maximum paleointensity values
IZZI method
For this type of experiment, a similar acceptance criterion to that used for the TC experiments was considered, and paleointensity estimations were performed also with the ThellierTool4.22 software (Leonhardt et al. 2004). No reliable results could be obtained from Flow 1 (specimens X003 and X007), except for one sub-specimen (X003C-2). Negative pTRM checks due to alteration, even at temperatures below 400 °C, and a zig− zag type behavior of the magnetization component observed at the Zijderveld plot precluded the estimation of PI values for this flow. One must note, however, that corresponding κ-T plot seems to be quite reversible up to a temperature of ~ 450 °C (Fig. 3) and provided no clue for these unsuccessful results. Flow 2 (specimens X014 and X017) yielded consistent and quite reliable specimen's mean results of 49.4 ± 4.4 and 49.5 ± 3.6 µT, respectively, with a flow mean result of 49.4 ± 3.7 µT (n = 8). Flows 3 and 4 (specimens X029 and X032, respectively) yielded also consistent and quite reliable specimen's mean results of 76.5 ± 3.2 and 63.9 ± 1.5 µT, respectively, although significantly higher than the underlying flow. For Flow 5 (specimens X041 and X042) two somewhat different specimen's mean results of 68.2 ± 6.0 and 59.4 ± 3.6 µT, respectively, were obtained, with a flow mean result of 63.8 ± 6.6 µT (n = 8). In case of Flow 6 (specimens X047 and X050) quite similar specimen's mean results of 63.9 ± 10.2 and 64.0 ± 2.3 µT, respectively, with a flow mean result of 63.9 ± 6.9 µT (n = 8). A representative Arai plot (Nagata et al. 1965b) is shown in Fig. 5c. Results are summarized in Table 4 and are graphically presented in Fig. 6.
Table 4 IZZI CRcorr paleointensity results for all six studied flows. Columns as defined in Table 2
Representative examples of the Arai plots (Nagata et al. 1965b) for the six flows are shown as Additional file 1: Figure S3. The corresponding vectorial plots (Zijderveld 1967) are shown as Additional file 1: Figure S4.
From the different individual specimen's results from flows 4–6, an overall Xitle's PI value of 63.9 ± 5.8 µT (n = 20) was estimated. Corresponding cooling rate-corrected values yield an overall PI value of 61.5 ± 4.3 µT (n = 19). As noted, the cooling rate correction of PI results slightly reduced the raw value and, in some cases, also the dispersion. Half of the 32 analyzed specimens showed k values < 0.164, seven 0.164 < k < 0.270 and only one a k > 0.270. Representative plots of the fitted circles to the data of the Arai diagrams are shown as Additional file 1: Figure S5.
Discussion and concluding remarks
The comparison between the results obtained by the three methods used (TC, IZZI CRcorr, and MS) shows some differences (Table 5). TC type results are in most cases higher than corresponding IZZI CRcorr values, except for Flow 5. On the contrary, MS data are in most cases significantly lower than the corresponding Thellier-type values, except for Flow 2 and Flow 5. For this last flow, a PI of 61.8 µT, compatible with those obtained from Thellier-type methods, was obtained. In general, the thermochemical alteration—attested by Avg εalt > 10%—seems to be the main cause for the inter-method differences observed.
Table 5 Summary of the mean PI values from three methods for the six flows
Taking into account that consistent results obtained with methodologies relying on dissimilar physical bases can be regarded as an alternative means to support the reliability of paleointensity determinations (e.g., De Groot et al. 2015; Enterpinar et al. 2016; Monster et al. 2015b; Calvo-Rathert et al. 2016), similar results for Flow 5 obtained by the three methodologies should be considered as the most reliable PI value for this flow. A mean multi-method PI flow value of 62.1 ± 5.9 µT (n = 12) was obtained for Flow 5.
The results obtained from the Thellier-type methodologies are very similar in the cases of Flow 4 and Flow 5, and slightly different in the case of Flow 6 (Fig. 6). Overall mean PI flow values from flows 4 to 6 obtained by the TC methods used yielded 68.4 ± 5.6 µT and 61.5 ± 4.3 µT for the TC and IZZI CRcorr methods, respectively. Therefore, the cooling rate-corrected IZZI result could be considered as the most reliable PI result for the flows 4–6 sequence of the Xitle.
As a support for the reliability of the obtained results, Alva-Valdivia et al. (2020) recently carried out a reassessment of paleointensity estimated of a single lava flow from Xitle volcano by means of the multispecimen domain-state-corrected method, obtaining nearly identical paleointensity results of 60.5 ± 4 µT. Figure 7 shows a summary of the results obtained in this investigation, together with the results obtained in previous studies on lavas of the Xitle volcano. We must mention that previous studies on potteries or baked sediments found beneath Xitle's lavas were excluded since this would inevitably add another factor (anisotropy of thermoremanence) to be considered in the study.
Box-and-whisker plots showing the available lava PI data for Xitle, together with those obtained in this investigation. N-65: Nagata et al. (1965a); UF-96: Urrutia-Fucugauchi (1996); GH-97: Gonzalez et al. (1997); B-97: Böhnel et al. (1997); M-01: Morales et al. (2001); B-03: Böhnel et al. (2003); M-06: Morales et al. (2006); AV-20: Alva-Valdivia et al. (2020); Flow 5 (MS): mean PI result for Flow 5 obtained with the MS method; Flow 5 (multi-method): mean PI result for Flow 5 obtained with the TC, IZZI CRcorr and MS methods; flows 4–6 (IZZI): mean PI result from flows 4–6 obtained with the IZZI CRcorr method. The dotted line and shaded area correspond to the Xitle's mean IZZI CRcorr paleointensity value obtained in this study, and its associated standard deviation
At this point, a comparison of our results against the different model predictions available—CALS10k.1b (Constable et al. 2016), SHA.DIF.14 k (Pavón-Carrasco et al. 2014), A_FM (Licht et al. 2013), etc.—seems natural. Nonetheless, the different model predictions available show, for some intervals, significant differences.
On the other hand, even though the Xitle is one of the youngest volcanoes, a breadth age-interval for the Xitle's eruption does (still) persist, as mentioned above. Moreover, among the different age intervals proposed so far, that of Siebe (2000) and Gonzalez et al. (2000) (1670 BP) would seem to be the more reliable one. However, Urrutia-Fucugauchi et al. (2016) recently carried out a bootstrap analysis of radiocarbon dates and paleomagnetic data—by correlating full vector data with the geomagnetic secular variation reference model (SHA.DIF.14 k)—for the Xitle lava flows to constrain the best date estimates, from which new age estimates (2041 BP and 2035 BP, respectively) for the eruption were determined. Therefore, an attempt to correlate PI estimates with the different model predictions would seem to be somewhat meaningless at this stage.
Another interesting result observed from Fig. 6 is that the IZZI CRcorr PI values for flows 1 and 2 are quite similar between them, but also quite different from those for flows 4–6. Cervantes-Solano et al. (2019) have suggested that this lava-flow sequence could represent, at least, two eruptive periods; one related to the Xitle volcano (flows 4–6), and other older (flows 1−2) of an unknown source. Nonetheless, Delgado-Granados et al. (1998) had already speculated the ages of the ~ 4000 yr cluster identified by Urrutia-Fucugauchi (1996) could represent the age of Tenantongo Basaltic Andesite, being geomorphologically very similar to Xitle volcano lavas, and thus, very easy to confuse.
Whether or not the mean paleodirections of flows 1 and 2 are statistically different from those of flows 3 to 6 is difficult to ascertain. However, a simple look at the corresponding equal-area projections suggests slightly different mean paleodirections (Fig. 8). Separated equal-area projections for flows 1 and 2 and for flows 3 to 6 are shown as Additional file 1: Figure S6.
Equal area projection showing the corresponding mean paleomagnetic directions for flows 1 and 2 (red dot), and for flows 3 to 6 (blue dot), together with their corresponding alpha_95 intervals
The reassessment of the archeomagnetic dating of the different flows through the reference model SHA.DIF.14 k, using the reliable IZZI CRcorr PI data obtained in this study, yield the following periods as the most probable ages: [1620 BC–1520 BC] (3570 BP- 3470 BP) for Flow 1; [1749 BC–1597 BC] (3699 BP- 3547 BP) for Flow 2; [61 BC–5 BC] (2011 BP- 1955 BP) for Flow 3; [55 BC–1 AD] (2005 BP–1949 BP) for Flow 4; [24 BC–270 AD] (1974 BP–1680 BP) for Flow 5; [164 AD–342 AD] (1786 BP–1608 BP) for Flow 6, thus, supporting the different origin for the first two flows (Flow 1 and Flow 2) of the sequence on the one hand, and the multi-modal age distribution obtained by Urrutia-Fucugauchi (1996) on the other hand.
Dating of a burnt wood fragment found beneath a lava flow from Unit V yielded and age of 1960 ± 65 yr BP (Ortega-Guerrero et al. 1993), in good agreement with the archeomagnetic dating results. Archeomagnetic dating plots for the different flows are shown as Additional file 1: Figures S7.1–S7.6.
As evidenced from the results obtained, the large scatter of PI values obtained in previous studies should be attributed to the use of relaxed acceptance criteria on the one hand, and on the undetected non‐ideal behavior—mainly MD effects and alteration during laboratory heating—on the other hand. This is comprehensible since those studies were carried out before stringent protocols—including extra experimental steps for the quantification and, when possible, the correction of non‐ideal behavior (Paterson 2011)—were proposed, and due to the lack of standard tests.
From the results obtained in this investigation, the practice of stricter acceptance criteria, together with CR correction and curvature estimation, would help to eliminate the "enigmatic" character to the Xitle's lava flows.
AAD:
Acceptable angular deviation
AV-05:
Alva-Valdivia et al. (2005)
B-03:
Böhnel et al. (2003)
BP:
Before present
BCU:
Ciudad Universitaria Basaltic Lava member
CRcorr:
Cooling rate correction
DRAT:
Difference ratio
Dekkers–Böhnel method
DSC:
Domain state correction
Flow 5 (MS):
Mean PI result for Flow 5 obtained with the MS method
Flow 5 (Multi-method):
Mean PI result for Flow 5 obtained with the TC, IZZI CRcorr and MS methods
Flows 4–6 (IZZI):
Mean PI result from flows 4–6 obtained with the IZZI CRcorr method
FC:
Fraction correction
GH-97:
Gonzalez et al. (1997)
IZZI:
Infield, Zero field, Zero field, Infield paleointensity method
M-01:
Morales et al. (2001)
MAD-anc:
Anchored maximum angular deviation
Multidomain grains
Multi-specimen method for paleointensity determinations
N-65:
Nagata et al. (1965a)
NRM:
Natural remanent magnetization
Paleointensity
PIcrc:
Cooling rate-corrected PI
pTRM:
Partial thermoremanent magnetization
TC:
Thellier–Coe method
TRM:
Thermoremanent magnetization
UF-96:
Urrutia-Fucugauchi (1996)
UNAM:
VBA:
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We thank the editor and two anonymous reviewers for their exhaustive reading of the manuscript and their wise suggestions. NP appreciates the economic support of CONACYT for the Ph.D. program fellowship.
AG acknowledges the financial support of CONACyT 252149 and UNAM-PAPIIT projects IN105214 and 1N101920.
Laboratorio Interinstitucional de Magnetismo Natural (LIMNA) y Servicio Arqueomagnético Nacional (SAN), Instituto de Geofísica, UNAM, Unidad Michoacán, Morelia, Mexico
Juan Morales & Avto Goguitchaichvili
Posgrado en Ciencias de la Tierra, UNAM, Unidad Michoacán, Campus Morelia, Morelia, Mexico
Nayeli Pérez-Rodríguez
Escuela Nacional de Estudios Superiores Unidad Morelia, UNAM, Morelia, Michoacán, Mexico
Miguel Cervantes-Solano
Avto Goguitchaichvili
All authors contributed to the study conception and design. Fieldwork and paleomagnetic determinations were done by Miguel Cervantes-Solano. Material preparation, data collection, and analysis were performed by NP-R. The first draft of the manuscript was written by Juan Morales and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Correspondence to Juan Morales.
Additional figures.
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Morales, J., Pérez-Rodríguez, N., Goguitchaichvili, A. et al. A multimethod paleointensity approach applied to the historical Xitle lava flows (Central Mexico): towards the accurate paleointensity determination. Earth Planets Space 72, 101 (2020). https://doi.org/10.1186/s40623-020-01232-z
Xitle volcano