The morning after I had hiked the Tongariro Crossing and Sue had visited Mt Ruapehu, we drove the 1/2 hour to the town of Taupo which is located on the shore of Lake Taupo. The lake is well known to volcanologists because it is actually a caldera volcano. Caldera volcanoes are different than cone volcanoes. Cone volcanoes generate many small eruptions from the same site. An example in New Zealand is Mt Ruapehu which has been erupting almost continuously for about 260,000 years. The many frequent eruptions of the volcano usually produce between 0.001 and 0.2 cubic km of lava and ash per eruption, which has created a steep-sided cone.Caldera volcanoes such as Taupo produce larger and less frequent eruptions. Caldera volcanoes are created when magma rises through channels from hot spots in the mantle into vast reservoirs beneath the Earth’s crust. The rising magma creates pressure beneath the crust, bulging the crust upwards as the pressure increases. This chamber increases to an enormous size, until finally, the pressure becomes too great and the ground ruptures in an explosion powerful enough to hurl magma, ash and gases far into the atmosphere in volumes so large that debris can rain down for thousands of square miles. As the pressure subsides, the ground collapses into the depleted magma chamber below the crust, creating a huge depression called a caldera. Sometimes the eruptions are as large as 50 cubic km or even bigger, and form new caldera structures. Other eruptions are smaller and contained within the existing caldera like many of Taupo's eruptions over the past 20,000 years. These small eruptions are typically between 0.5 and 10 cubic km.
When I was in the US, I saw a program on the Discovery Chanel about these caldera volcanoes which the program called “super volcanoes”. Examples include Yellowstone in the US where there are a sting of calderas that stretch in a 350 mile line across parts of Idaho and Wyoming. Others are Lake Toba, Sumatra Indonesia, Long Valley, California, Valles Caldera, New Mexico, and Aira, Japan.
About 26,500 years ago, the Oruanui eruption at Taupo produced huge volumes of ash and other volcanic material that buried parts of the central North Island. Close to the vent the ash reached depths of about 100m. Roughly 800 cubic km of pumice and ash were ejected in this one event. The Oruanui eruption is thought to have formed the caldera now filled by Lake Taupo,
In 181 AD, Taupo erupted in what is described as the most violent and explosive known in the world in the past 5000 years. At the climax of this eruption, about 30 cubic km of pumice, ash and rock fragments was erupted in only a few minutes and travelled horizontally as a liquid flow, moving at speeds estimated at between 600-900 km/h. The eruption column heights reached 45-50 km (about twice the height of Vesuvius 79 AD and over a hundred times more than Mount St. Helens.). Ash was distributed over an extremely large area. New Zealand was not inhabited at the time of the eruption, but today that same area is populated by over 200,000 people. The effects of the eruption were seen in the sky as far away as Europe and China.
There have been many smaller eruptions since 181 AD. Today Lake Taupo still shows signs of life, which New Zealanders have put to good use. Ample hot springs and other hydrothermal activity enable New Zealand to generate about 8 percent of its electricity at a geothermal plant on the north side of Lake Taupo, at Wairakei.
The town of Taupo, located on the shore of Lake Taupo is thriving. I had just visited Taupo in 2004, but after only three years absence the town looked bigger with more developments in the suburbs and more stores downtown. Despite the growth, Taupo is still a nice town on the shore of the beautiful lake and ideally located for fishing, kayaking, hiking or other outdoor sports.
Sue and I spent the morning tramping along the Waikato river which at a length of 264 miles (425 km) is the longest river in New Zealand. The last time that I was here, I was impressed by the clarity of the water and its color. The water has an opaque, aquamarine color and patches of sand on the bottom appeared aquamarine as well. However, on the day that we walked, the water level of the river was quite high which reduced the visibility. Our walk took us past people sitting in the river where hot water bubbles from the ground and mixes with the cold river water. We also saw the Huka Falls where the Waikato River narrows from roughly 100 metres across into a hard rock granite canyon only 15 metres across. The volume of water flowing through often approaches 220,000 litres per second.In the afternoon, we hired kayaks to paddle down the river. The water was flowing so swiftly that we barely needed to paddle to go at a nice pace. We were each in single person kayaks, but our guide was in a special kayak design that had been designed and built in New Zealand specifically for small streams. Our guide was telling us that they can not make the kayaks fast enough to supply the world-wide demand for the small, stable boat. Currently, production is by hand, but maybe that will change as its popularity grows. Even on our small trip the kayak was noticed by other people who wanted to know more about it.
Our conversation with our guide turned towards emigration and he mentioned that a lot of young people are keen to move from New Zealand. Although New Zealand is a beautiful country, young people are lured by higher paying jobs elsewhere. For example, a lot of engineers wind up in Australia because they can earn more money there than in New Zealand.
Our trip took us past a bungee jump where high cliffs near the river provide a great opportunity
for people to jump from a platform and to pay handsomely for doing so. Although the quickly flowing water made paddling easy, it created some nice rip currents, one of which I got caught in. I was just paddling along, minding my own business when my kayak went out from under me. Fortunately, I was actually keen on taking a swim anyway and so I didn’t mind getting wet and fortunately my sunglasses stayed on my head. After I got back into my kayak, we made a stop at the hot springs for a nice sit in the water. There were a lot of people enjoying the warm water and it felt like sitting 
in a pub because people were all chatting with each other and just hanging out.The next morning, we packed our bags and headed northeast. However, before we left the town, we stopped at the Wishart Estate Winery for a wine tasting. We arrived at a very good time because we were the only people in the store at that time of day. We had to wait for a few minutes while the manager finished a telephone conversation which gave us time to look about and to read a recent news article about the manager and the winery.
In December, Arnolds Schwarzenegger's personal assistant was in New Zealand to scout places for the governor to see during his upcoming visit. The assistant visited the winery and decided that the 2002 Wishart Hawke's Bay Legend would be a perfect gift for Arnold to have with his Christmas dinner. The assistant arranged to have several bottles of the wine delivered to her in Auckland so that she could fly them back with her at the end of her trip. Ms. Olsen, the manager of the winery boxed up the wine and sent to Auckland by courier. However, the day that the assistant was to fly out, she called the manager to say that the wine had not arrived. The manager called the courier and upon learning that the courier had broken all of the bottles on route, she closed the shop, put two cases of wine in her car and drove up to Auckland. She arrived just in time to meet the assistant before her flight left. Fortunately, customs let the bottles through without charging duty on the wine and the governor was able to enjoy them for Christmas. Since then, Ms Olsen has received an email inviting her to dinner with Arnold Schwarzenegger at the US ambassador's residence in Wellington later in the year. And once the story hit the newspapers, orders for Arnold’s favorite wine have skyrocketed.
The manager poured both Sue and I a glass of the first wine for us to sample and we tried the wine under the manager’s watchful eye. When we were finished, she asked us if we would like some tips on wine tasting. It was one of those humbling moments where you are being told that you are doing something wrong and you have a moment to decide if you want to admit that you have no idea about what you are doing even if you thought that you did. We decided to ask for help and I am very glad that we did because we learned a lot. First of all, the wines that we were sampling included reserves which are rarely given at tastings and so we were working with some very nice wines which is probably why the manager was keen on us drinking them properly. Some of the things that we learned included (I hope that I remember these correctly before putting them on the blog!):
* Swirl the wine in the wine glass. If after the wine has settled to the bottom of the glass, you see a syrupy liquid clinging to the sides of the glass. The more liquid clinging to the sides of the glass, the higher the alcohol content of the wine.
* When sampling red wines, hold the glass up to the light and tilt the glass a little. If you see an orange ring around the wine in the glass, it indicates that the wine had been oxidized from standing open for too long. If this happens to a glass that you have received in a restaurant or a bar, it is best to send it back and to ask for a glass from a freshly opened bottle. The manager told us that the restaurant will probably know that the bottle has been open for too long and will replace your glass.
* Smelling the wine is very important to tasting the wine. We were told to put our nose into the glass and to take a deep breath to fully appreciate the flavors of the wine. The manager then quizzed us as to the flavors we smelled in each wine. It is amazing that you can smell the complex flavors in some of the wines including things that you would not think of such as cut grass (especially in Marlborough Region Sauvignon Blanc), oaks, berries and a host of other flavors.
My favorites from the wines that we tasted were the Lonely Mountain Pinot Noir 2005 at $35 a bottle and the Te Puriri Melot Rose at $17.50 a bottle. Arnold’s favorite ran at $33 a bottle.
After our winery tour, we continued on a bit to see the Craters of the Moon thermal area in
Wairakei Tourist Park. The park includes steaming ground, mud pools and explosion craters which suddenly sprang up in the 1950's when the nearby power station lowered underground water levels causing the water in the underground reservoirs to boil more violently, producing more steam which escaped in the park. We also stopped by the Wairakei Field where steam and hot water are extracted from the ground to produce electricity. The field is massive and is littered by large, silver and white pipes that run this way and that as the water and steam is collected and sent to the power plant which is located miles away. The scheme was the first geothermal plant in the world to use very hot water as the source of steam used to drive the turbines. With an annual production of 1550 GWH, the plant produces 4.3% of New Zealand’s electricity. However, there have been complaints that tapping the hot water and diverting it to the plant has decreased the thermal activity in the area.One other stop of interest that we made during our drive was at the Honey Hive which claims that “If the bees make it, we've got it!” The store had every product derived from honey that you can think of including liquors, cosmetics and treats such honey ice-cream. All of the products could be sampled including the honey wines. There was an indoor hive where you could watch the bees at work and a lot of really good educational information about bees.
Finally, we arrived in the city of Rotorua where we would be spending the next few days.
There were lots of references used for this post. Included are:
The Discover Chanel Program
New Zealand Minerals Industry Association
GNS Science
No comments:
Post a Comment