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In this issue...Fun Fact…TREASURE…Odyssey-Marine…FEATURE ARTICLE…WORLD’S OLDEST TEMPLE COMPLEX UNCOVERED … THOM’S COLUMN… Rockhound Recipes and Tips… TRAVEL…Lands of legend 2…Earthwatch…Chaiten (volcano) FEATURE ARTICLE… Meet the members… —RHS1 News.

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FUN FACT OF THE MONTH…Tastes like T- Rex.

Scientists have discovered that the closest living relative of Tyrannosaurus Rex are chickens and ostriches rather than modern reptiles. This classification was made possible from studies of proteins preserved in soft tissue of a bone found in the Wyoming/Montana area in 2003. Until the find of the preserved soft tissue made this study of T. Rex proteins possible, the only evidence for the relation between birds and dinosaurs was in the morphological similarities between the skeletal structure of the animals.

Gallus Rex.

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WORLD’S OLDEST TEMPLE COMPLEX UNCOVERED

The stone shrine of Gobekli Tepe.

The stone shrine of Gobekli Tepe is confounding Archaeologists everywhere. The stones have been dated to 9,500 BC. That’s almost twice the age of the first Mesopotamian cities. It is 7,000 years older than Stonehenge, the most well known of stone circles.

The temple, found by Klaus Schmidt, member of the German Archaeological Institute, is located about 345 miles North of the Turkey border in Syria, at the edge of the Anatolian plateau. At this time only 4 of an estimated twenty have been excavated. They range from 10 to 30 meters across. The stones bear carvings of boars, foxes, lions, birds, snakes, and scorpions. These carvings are not writing, but may be sacred symbolism. Schmidt’s hypothesis is that the site is a meeting point for rituals. There has been no discovery as of yet of houses or graves nearby. Two T shaped columns in the center of the complex have arms and hands, but no faces. He believes they are early representations of gods. No clues have been forthcoming at this date.

a T column Gobekli Tepe.

The stones are of great archaeological significance not only because of their great age, but because it has been the contention of scientists that only post agricultural civilizations had the capabilities to build monumental sites. Yet Gobekli Tepe contains a complexity not previously known to have existed in pre-Neolithic civilization. The stones were moved from local quarries, a distance of 100 to 500 meters. Some of these stones weighed 10 to 50 tons each. That would have taken major amounts of organization and human power to achieve.

For some reason the complex was deliberately covered with soil around 8,000 BC. Why the complex was covered is a mystery, but the action allowed the preservation of the site for us to study 10,000 years later.

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Odyssey Marine Exploration:

Odyssey’s President Mark D. Gordon To Keynote At The Detroit Science Center’s 2008 Detroit Science Gala

“Shipwreck”

Interactive “SHIPWRECK! Pirates & Treasure” exhibit
makes a big splash at DSC

Tampa, FL – April 30, 2008 – Mark D. Gordon, President of Odyssey Marine Exploration, Inc. (NasdaqCM: OMEX), the world leader in the field of deep-ocean shipwreck exploration, will deliver the keynote speech at the 2008 Detroit Science Gala hosted by the Detroit Science Center on May 9, 2008. The Detroit Science Center is the current host venue of Odyssey’s successful multimedia exhibit “SHIPWRECK! Pirates & Treasure”.

The Black Tie event, themed “Explore the Depths of the Detroit Science Center” is expected to be attended by over 650 guests, among them Congressman Joe Knollenberg of Michigan’s 9th District, Honorary Host Robert L. Nardelli, Chairman and Chief Executive Officer of Chrysler LLC, and local artist Greg Lashbrook. The gala is sponsored and/or supported by the three major Detroit auto manufacturers.

“I’m looking forward to being a part of the Detroit Science Center’s Gala, which celebrates engineering, technology and science while showcasing DSC as a world class host of high-profile exhibits such as our current “SHIPWRECK! Pirates & Treasure” exhibit,” said Mark D. Gordon, Odyssey’s President and Chief Operating Officer. “The Detroit Science Center has done a magnificent job hosting and promoting our exhibit, and we’re thrilled with the enthusiastic reception “SHIPWRECK! Pirates & Treasure” has received in Detroit since its opening in March. Following our well-accepted engagement at Tampa’s Museum of Science and Industry, this success demonstrates yet again the viability of our concept of a traveling exhibit in collaboration with experienced host venues.”

“SHIPWRECK is truly among the top traveling exhibits to be hosted here at the Detroit Science Center,” said Todd Slisher, the Science Center’s Vice President of Science Programs. “By bringing this exhibit to our museum, Odyssey Marine Exploration demonstrates its commitment to our common mission of showcasing technology to inspire future scientists and engineers to pursue further education and careers in those fields,” said Slisher.

The exhibit displays authentic artifacts from many different shipwrecks, with a spotlight on treasures and artifacts of the SS Republic. In addition to having the opportunity to closely inspect shipwreck artifacts, exhibit visitors will also get to experience the various steps in shipwreck exploration. In a fascinating behind-the-scenes look, guests can use research and technology to locate shipwrecks, pilot a real robot submersible, test their dexterity using a manipulator arm to pick up coins one at a time and identify artifacts as they are located on the sea floor. The Detroit Science Center also showcases a visiting exhibit of shipwreck treasures from the Great Lakes to complement Odyssey’s treasures from the world oceans.

Tickets can be purchased online at the Detroit Science Center’s website at www.detroitsciencecenter.org

Odyssey Marine Exploration Announces First Quarter 2008 Results

Tampa, FL – May 6, 2008 – Odyssey Marine Exploration, Inc. (NasdaqCM: OMEX), the world leader in the field of deep-ocean shipwreck exploration, today filed a quarterly report with the Securities and Exchange Commission detailing results of the Company’s first quarter 2008.

For the first quarter of 2008, Odyssey reported revenue of $.3 million, compared to $2.2 million in the first quarter 2007. The Company also reported a net loss of $6.8 million, compared to a net loss of $3.8 million in 2007. The net loss per share for the first quarter was $.14, compared to a net loss of $.09 per share in the first quarter 2007.

“We are optimistic about our 2008 prospects even though our first quarter financial results are substantially down from the previous year. We are going through some major adjustments in our coin marketing strategy to ready ourselves for international distribution of our current and future products,” said Greg Stemm, Odyssey’s Chairman and Chief Executive Officer. “So far, we have yet to realize the benefits of some new international strategic relationships but believe they will play a significant role in the future. To increase revenues, we have begun adjusting our sales structure and expanding our distribution channels with a broader base of coin and collectible marketers both domestically and internationally in preparation for additional inventory with international appeal. To enhance our shipwreck search and recovery capabilities, we performed extensive scheduled maintenance and substantial upgrades on our vessels, the Odyssey Explorer and the Ocean Alert , adding some new technology that will significantly add to our operational capabilities. Our 2008 marine operations activities are underway with work in the Atlas search area and we are looking forward to an exciting season. With the Black Swan , Firefly, Atlas and several other confidential projects on our radar, I am excited about our future and the continued execution of our long-term strategy.”

FIRST QUARTER 2008 RESULTS

Revenue

Revenues for 2008 and 2007 were $.3 million and $2.2 million, respectively, representing sales of approximately 200 coins in 2008 and 1,280 coins in 2007. The decrease of $1.9 million in revenue for 2008 is primarily due to fewer coins sold in 2008 versus the same period in 2007. Also, the sales mix in 2008 represented all silver coins while the 2007 sales mix included approximately 35% gold coins which are priced much higher than silver coins.

Expenses

Operations and research expenses were $3.8 million in 2008, compared to $2.8 million in 2007. The $1.0 million increase was due to vessel operating expenses primarily associated with repairs and maintenance of the Odyssey Explorer . This work included main engine and generator strip downs, extensive steelwork repairs to meet vessel classification requirements, and accelerating four additional Class surveys, normally scheduled for July 2008, but executed early in order not to interfere with search and recovery operations in our prime work season.

Marketing, general and administrative expenses were $3.3 million in 2008 as compared to $2.7 million in 2007. Of the $.6 million increase, $1.0 million was related to additional share-based compensation costs ($.7 million) and cash separation payment ($.3 million) due to the departure our former Chief Executive Officer in January 2008, offset by a reduction in advertising and commissions of $.4 million due to lower direct coin sales.

QUARTERLY OPERATIONAL UPDATE

Odyssey has numerous shipwreck projects in various stages of development around the world. Additional information about some of these projects is set forth in our Annual Report on Form 10-K for the year ended December 31, 2007. In order to protect the identities of the targets of our planned search or recovery operations, in some cases we will defer disclosing specific information relating to our projects until we have located the targeted shipwreck or shipwrecks and determined a course of action to protect our property rights.

“Black Swan” Project

In May 2007, we announced the discovery and archaeological recovery of more than 500,000 silver coins weighing more than 17 tons, hundreds of gold coins, worked gold and other artifacts from a site in the Atlantic Ocean code-named, “Black Swan .” Odyssey has not yet been able to positively identify any vessel related to the site and has not publicly disclosed the location of the site in order to protect its security. We have identified the Nuestra Seora de las Mercedes y las Animas (the “Mercedes”), a vessel assigned to transport mail, private passengers, consignments of merchant goods and other cargoes, as one vessel potentially related to the “Black Swan” site but we have indicated that we are reviewing evidence which may contradict this hypothesis.

The Kingdom of Spain has filed claims in the U.S. District Court claiming certain rights to property relating to the “Black Swan.” We do not have the ability to immediately monetize the recovered cargo until we are awarded title or a total or partial salvage award by the U.S. District Court. Claims against the recovery have been submitted by Spain, and other parties may also assert claims. As a result, the potential value to Odyssey of this project is not possible to determine at this time, although we believe we will receive a substantial salvage award and/or title.

“Atlas” Search Project

We believe the “Atlas” project is the most extensive shipwreck search operation ever launched. A minimum of five high-value shipwrecks are believed to be in the search area, which encompasses more than 5,000 square miles. Odyssey began search operations during the 2005 season and resumed operations in April 2006. During the 2006 season, work was concentrated in the seven search block areas which encompass the “Atlas” target of highest value, code-named “Tripoli.” During 2005, much of the area was searched with high-resolution side-scan sonar. During 2006, a second pass was completed which included acoustic and magnetometer data-streams which helped Odyssey create a larger database of information. Overlaying all three layers provided an extremely precise, high-resolution map of the seven search blocks. We have identified the Merchant Royall, a British merchant vessel lost in 1641, as a possible vessel related to the site, although there is some evidence being examined that may contradict this theory.

The Kingdom of Spain has filed claims in the U.S. District Court claiming certain rights to Spanish property relating to this site.

While we did not conduct operations in the “Atlas” search area in 2007, we have commenced search operations and ROV inspections in this area in April 2008. For reasons of security and strategic confidentiality, we do not disclose the location of search operations within the “Atlas” project area.

“Firefly” Project

Odyssey and BDJ Discovery Group, LLC, or BDJ, filed a “Joint Motion for Substitution of Plaintiff” in the United States District Court for the Eastern District of North Carolina on February 21, 2008. The joint motion was granted upon filing and substitutes Odyssey for BDJ as plaintiff in the In Rem Admiralty case against the Unidentified Shipwreck Vessel, its apparel, tackle, appurtenances and cargo located in the waters of the Atlantic Ocean approximately 12 miles off the coast of North Carolina. On March 4, 2008 the Court entered an order granting Odyssey’s motion appointing Odyssey as substitute custodian for all artifacts from the site and requiring reporting within 30 days of activity.

In a separate agreement, BDJ has turned over all aspects of the project to Odyssey and assigned all of its rights to the artifacts and any wreck from which they originate to Odyssey in return for up to 15% of any proceeds from artifact sales after archaeological excavation, conservation, marketing and certain other expenses. Among other objects, a small number of gold and silver artifacts have been recovered from the site, but the identity of the shipwreck from which the artifacts originated has not yet been confirmed. In order to protect the site, no additional information about the artifacts recovered or operations at the site to date is being made available for release at this time. Odyssey performed survey and inspection operations on the arrested site during the later part of 2007 and is planning the next stages of survey and archaeological investigation of the site.

About Odyssey Marine Exploration

Odyssey Marine Exploration, Inc. (NasdaqCM: OMEX) is engaged in the exploration of deep-water shipwrecks and uses innovative methods and state-of-the-art technology to conduct extensive deep-ocean search and archaeological recovery operations around the world. Odyssey discovered the Civil War era shipwreck of the SS Republic in 2003 and recovered over 50,000 coins and 14,000 artifacts from the site nearly 1,700 feet deep. In May 2007, the Company announced the largest historic deep-ocean treasure recovery of over 500,000 silver and gold coins, weighing 17 tons, from a Colonial era site code-named “Black Swan.” Odyssey has several shipwreck projects in various stages of development around the world.

Odyssey offers various ways to share in the excitement of deep-ocean exploration by making shipwreck treasures and artifacts available to collectors, the general public and students through its webstore, exhibits, books, videos, merchandise, and educational programs. Odyssey’s “SHIPWRECK! Pirates & Treasure” exhibit is currently on display at the Museum of Science and Industry in Tampa, FL. For details on the Company’s activities and its commitment to the preservation of maritime heritage please visit www.shipwreck.net.

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For additional information, please contact Natja Igney, Odyssey’s Manager of Corporate Communications, at 813-876-1776.

SS Republic is a registered trademark of Odyssey Marine Exploration, Inc

Odyssey Marine Exploration believes the information set forth in this Press Release may include “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933 and Section 21E of the Securities Act of 1934. Certain factors that could cause results to differ materially from those projected in the forward-looking statements are set forth in “Risk Factors” in the Part I, Item 1A of the Company’s Annual Report on Form 10-K for the year ended December 31, 2006, which has been filed with the Securities and Exchange Commission.

Odyssey Marine Exploration P.O. Box 320057 Tampa, FL 33679-2057 www.shipwreck.net

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RHS1 Members News 

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I was hoping to put up some information about Herkimer Diamonds this month but was not able to get back to the digs as I had hoped. It seems that area doesn’t understand global warming and it was cold and raining the last two weekends. Oh well summer is still going to show up sometime….I hope.

For those of you who haven’t scouted around the site lately, there is a new page up on Gold just in case you’ve decided to get with the 2008 Gold Rush. You will find it on the “Main Menu” page along with a lot of other stuff you might have forgotten or just not realized even existed on the site. Indy is a bit like an elf, ya know. He likes to sneak in and surprise us with something new every now and again so don’t forget to visit the main menu from time to time ya just never know what you will find there.

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FOSSILIZED HUMAN BRAIN TISSUE FOUND

Human Brain.

It is rare to find soft tissues such as brain tissue fossilized, but fossilized human brain tissue has been found. I thought you might like to see it yourself. Would you have recognized it as a fossil? VIEW VIDEO

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ROCKHOUND RECIPES & TIPS

Blue Cheese Potato Salad .

Well the old guy with the funny recipes is having a birthday in a few days. To celebrate I’m going for a long ride on my motorcycle, then having a little cook out in the yard. Nothing fancy, probably just Hot Dogs and Hamburgers. But I will be having this salad that is a slightly different take on Potato Salad. If you like Blue Cheese you may start making this more then regular potato salad, and yes it is that good.

By the way I’ll be 55 on the 10th. Five more years and I hit middle age.

Blue Cheese Potato Salad

—–Mix together—–

• 2 bunches green onions — washed and chopped
• 5 stalks celery — chopped
• 1/2 cup fresh dill — chopped
• 1 cup mayonnaise
• 1 cup sour cream
• 2 teaspoons lemon juice
• Salt and pepper to taste
• —Add about—– 1/2 cup crumbled blue cheese — to 3/4, and mix wellLet mixture sit overnight (very important), as the blue cheese needs to blend with the dressing. Then, toss dressing with about 5 pounds of cooked, cut potatoes, more salt, and a little vinegar. I use small red potatoes, and then cut them into quarters or sixths if they are larger. I cut them first and then cook them, just until they are done, and then rinse them in cold water to stop cooking. Then I usually toss them with a little vinegar and salt – remember, potatoes SOAK up salt.

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About Thom…

Thom Meyer is a retired professional chef who has a degree in Culinary Arts – Also an avid camper and most importantly a person who likes to eat. Lately he has been involved in marketing and building websites when not using WordPress for them, a process of which in some circles he is considered an authority. Among his many websites that he maintains are www.recipes-4-all.com and www.wp-revealed.com

“When the going gets weird, the weird turn pro”
Hunter S. Thompson

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TRAVEL

VACATIONING IN LANDS OF LEGENDS
part two

Oklahoma .

Oklahoma isn’t a state you hear much of during rockhound discussions. That’s a shame. Oklahoma is a land rich in possibilities for the adventurous rockhound. Gemstones, gold, relics, ghost towns, fossils, and legend upon legend of lost caches await in the mountains and streams of the state.

Malachite.

Not widely recognized for it’s beautiful quartz crystals, in actuality the quartz belt that finds it’s beginnings near Little Rock, Arkansas actually runs all the way to Northern Oklahoma. A quarry in Johnston Co., Oklahoma, produces fabulous rutilated quartz crystals, and smoky quartz also can be found throughout the quartz belt. Quartz is not the only mineral worth a bit of hunting, though. Malachite, garnets, fluoride, gypsum roses, zircons, turquoise, and a hundred other minerals can be found throughout the state.

Quartz.

In Murray county beautiful petrified wood, some of which is thought to be the oldest petrified wood, is the hunter’s main aim. Wood is not the only fossil that can be found. Paleontology enthusiasts have a whole range of fossils to discover.

Oklahoma was once covered with a shallow sea. It rested south of the equator. Fossils can be found of trilobites, brachiopods, corals, clams, snails, stromatolites, and fish can be found dating to the Ordovician period. Vertebrate fossils can be found from later eras, but mostly those of marine vertebrae as Oklahoma was underwater until recent eras.

Homotelus.

Gold prospectors will want to visit the streams and rivers of the Wichita Mountain which is the seat of the Oklahoma gold rush era. Spaniards and Indians were the first gold miners in the area and many old mines can still be seen throughout the area. In the final years of the 1800’s thousands of prospectors staked their claims in the Wichitas. Gold, silver, and copper can all be found by the prospector there. The old mines are extremely hazardous and it is warned that prospectors and hikers should stay out of the shafts and tunnels at all costs.

Wichita Canyon

Ghost towns, old mining camp sites, and early homesteads still hold promise of treasure hunters. For hunters with a flare for following the legend – there a legends plenty in this Historically rich State. From families burying treasures to keep them safe from soldiers, Indians, and outlaws to the outlaws themselves hiding loot and never returning for it, there are legends to perk the interest of even the most skeptic of hunters.

Many legends of buried caches are reported in the Devil’s Canyon and Twin Mountain areas. The legends include hidden caves, lost mines, fights between Indians and Mexicans, and a lot of caches stolen and buried. Spanish missionaries supposedly left a silver casket filled with some sort of valuables in a lost cave. When hunting the many caches lost in Devil’s canyon you would be wise to be aware that these treasures are supposedly guarded by ghosts wearing armor.

Gloss Mountains.

Twin Mountains is said to contain a cache of gold worth $100,000.00 when it was buried about a hundred and fifty years ago. There are many stories about the cache including one that it was buried by Jessie James who is thought to have hidden caches of stolen gold around the state. Two army payrolls were supposedly buried to hide them from Indians, one at Twin Mounds near Jennings and the other in the aptly named Cache in Comanche County. Another legend reports that an outlaw stole a payroll from Fort Sill and buried it somewhere on Otter Creek near Cold Springs while being pursued. A bandit’s cache of silver coins still lies hidden somewhere on Holsum Valley road in Le Flore County.

These legends are just a few of the almost endless number of Oklahoma treasure stories that the visitor may pursue during a trip to this region of the US. Whether you plan on mixing a bit of treasure hunting in with digging for crystals or whether you are going to mix some digging for crystals in with your treasure hunting, Oklahoma is not a state you will soon tire of.

This state can be extremely hot during the summers, but is mild during the winter months and is a great destination for Northern hunters who are not able to hunt in the snowy winters. Make sure you take clothes for cool and warm weather as mountain areas can get chilly at night even when days are intensely hot.

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MEET THE MEMBERS…

I thought from my previous “Meet the Members” articles that people might be getting the idea that rockhounding is a men’s only interest. It’s definitely time to change that impression. I really am not the only female who likes to wander around the wilderness getting dirty and hauling heavy backpacks of specimens back to the rig. Trust me on that one. This month it is my pleasure to introduce member Jenifer Long – aka “jenwa66”. Jen’s just another one of the many gals who you might run into at a gas station or cafe in rockhound territory with dirt under her nails and on her face � and smiling about it on a good hunt day. Here she is to tell you about her rock fetish:

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My name is Jenifer Long. Jeni to most. I live in Portland, Oregon and work as a cardiovascular technologist/special procedures technologist at Providence Portland Medical Center. I have been interested in rocks and minerals since I got my first tumbler as a little girl. Back then I collected rocks from the beaches or purchased them from tourist traps along the way. I would take them home and have to wait impatiently as the tumbler did its thing.

I grew up in Michigan so my favorite stone was the Petoskey Stone. Petoskey stones are found in the Gravel Point Formation of the Traverse Group (along the upper rim of the mitten). They are fragments of a coral reef that was originally deposited during the Devonian period, about 350 million years ago. According to legend, Petosegay a descendant of a French nobleman and fur trader, Antoine Carre, and an Ottawa princess. Petosegay, meaning “rising sun” “rays of dawn” or “sunbeams of promise”, was named after the rays of sun that fell upon his newborn face. (Wikepedia and memory) They are the Michigan State Stone.

I got out of rockhounding as a teenager, (As a teenager it was too uncool to dig for rocks. Ha ha) but, when I moved to the northwest, I found a whole New World along with my husband. Here I have found agates, jasper, petrified wood, thundereggs, and obsidian. Last year my husband and I went digging for Oregon Sunstone at the Dust Devil Mine, then went down to Davis Creek and up to Glass Butte and found a lot of different types of obsidian. The coolest thing that we experienced were the petroglyphs along the edge of the Hart Mountains. You can only get there with a four-wheel drive and they were amazing! It is rather humbling to be where the ancient shaman were in their quests for higher knowledge.

Jenifer Long designs.

I have a very good friend at work that has been a rockhound for many years. Ernie has taught me many, many things. He has given me specimens so that I know what to look for as well as providing me with a few very special gems that he dug along his way. I love being out in nature. I love being in the woods, deep in the rivers, coughing up sand in the desert, and checking out all the wildlife when hunting for an elusive treasure. I think I enjoy rock hunting more for the pleasure of being one with Mother Nature more than anything. I do however enjoy seeing little kids faces light up when they go through our polished stones at craft fairs and festivals and find a special treasure for themselves. Maybe we’ve made rockhounds out of a few of them.

My husband is the main force in cutting and shaping the stones that we find. He does all the dirty work and I make the finds into jewelry or ornaments of various kinds. I think the one thing I am most proud of is a wind chime I made from picture jasper for my sister and brother in-law. Of course I didn’t take any pictures. Ugh!

Jenifer Long designs.

I just recently got a digital camera to take pictures so most of what I have done is not recorded. I do however have a blogspot, Jeniferlongdesigns.blogspot.com. I just learned how to get my pictures out on the web with the help of my stepson. Here I write little blurbs about what I’m doing and the things that I’ve made. I also hope that this this site will generate some exposure and orders. I have to get my paypal account up and running on it first though. I’m still a beginner when it comes to getting a website up and going so I don’t know what will happen from here. I have just had a lot of people ask if I have a website when they purchase my wares at festivals and craft shows. So, now the answer is yes. jenwa66 Jenifer Long

Jeniferlongdesigns.blogspot.com

 

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The small circular feature just above the center of this NASA International Space Station image (with north to the upper left) is Chaiten caldera. It is located 10 km NE of the town of Chaiten, the light-colored area along on the Gulf of Corcovado below and to the right of the caldera. This small, glacier-free, 3.5-km-wide caldera is of Pleistocene age, but has a rhyolitic Holocene lava dome.

NASA Space Station image ISS006-E-42131, 2003 (http://eol.jsc.nasa.gov/).

Image:Plume from eruption of Chaiten volcano.
The ash cloud from May 2008 eruption streching
into San Jorge Basin in the Atlantic Ocean.
(Click to enlarge)

Chaiten (volcano)

 

Spread

The plume that is often seen above an erupting volcano is composed primarily of ash and steam. The very fine particles may be carried for many miles, settling out as a dust-like layer across the landscape. This is known as an ashfall. If liquid magma is ejected as a spray, the particles will solidify in the air as small fragments of volcanic glass. Unlike the ash that forms from burning wood or other combustible materials, volcanic ash is hard and abrasive. It does not dissolve in water, and it conducts electricity, especially when it is wet. Ashfall can become cemented together by heat to form a solid rock called tuff. Ashfall breaks down over time, forming highly fertile soil, which has made many volcanic regions densely cultivated and inhabited despite the inherent dangers.

 

Atmospheric effects

When ash begins to fall during daylight hours, the sky turns hazy and a pale yellow color. The ashfall may become so dense that daylight turns the sky gray to pitch black, with the ash severely restricting visibility and deadening sound. A darkened ash sky lowers temperatures during daylight hours from what would otherwise be expected. Loud thunder and lightning as well as the strong smell of sulfur accompany an ashfall. If rain accompanies an ashfall, the tiny particles turn into a slurry of slippery mud. Rain and lightning combined with ash leads to power outages, prevents communication, and disorients people.

Very fine ash particles can remain high in the atmosphere for many years, spread around the world by high-altitude winds. This suspended material contributes to spectacular sunsets, as well as an optical phenomenon known as “Bishop’s Ring”, which refers to a corona or halo effect around the sun. High levels of ash high in the atmosphere causes climate change by cooling the globe for a few years following major eruptions. The last episode of ash-induced global cooling followed the Mount Pinatubo eruption of 1991. The most documented case in recorded history of this phenomenon followed the epic eruption of Mount Tambora in 1815, which led to the year without summer in 1816.

Dangers:

Volcanic ash is not poisonous, but inhaling it may cause problems for people whose respiratory system is already compromised by disorders such as asthma or emphysema. The abrasive texture can cause irritation and scratching of the surface of the eyes. People who wear contact lenses should wear glasses during an ashfall, to prevent eye damage. Furthermore, the combination of volcanic ash with moisture in the lungs can create a substance akin to liquid cement. Therefore, people should take caution to filter the air they breathe with a damp cloth or a face mask when facing an ashfall. Ash is very dense, as only 100 millimetres (3.9 in) of ash leads to the collapse of weaker roofs. A fall of 300 millimetres (12 in) leads to the death of most vegetation, livestock, the wiping out of aquatic life in nearby lakes and rivers, and unusable roads. Accompanied by rain and lightning, ashfall leads to power outages, prevents communication, and disorients people.

 Aviation

Volcanic ash jams machinery. This poses a great danger to aircraft flying near ash clouds. There are many instances of damage to jet aircraft as a result of an ash encounter. Engines quit as fuel and water systems become fouled, requiring repair. After the Galunggung, Indonesia volcanic event in 1982, a British Airways Boeing 747flew through an ash cloud that fouled all 4 engines, stopping them. The plane descended from 36,000 feet (11,000 m) to 12,000 feet (3,700 m) before the crew could manage to restart the engines.

 

Advisories concerning ongoing events

Increasing numbers of airplane incidents from atmospheric ash prompted a 1991 aviation industry meeting to decide how best to distribute information about ash events. One solution was the creation of Volcanic Ash Advisory Centers. There is one VAAC for each of nine regions of the world. VAACs can issue advisories and serve as liaisons between meteorologists, volcanologists, and the aviation industry.

 

References

Wikimedia Commons has media related to:

• A map of the 9 VAAC regions
• Ash Thickness and Particle Size Downwind from Mount St. Helens, Washington, on May 18, 1980
• Tephra Falls of the 1991 Eruptions of Mount Pinatubo
• What to do during an ash fall event
• Social & Economic Costs of Volcanic Ash to Aviation from “NOAA Socioeconomics” website initiative

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Image and info credits for this edition:

Wikipedia: Odyssey Marine Exploration: Nasa: Roger Weller Cochise College: Jenifer Long Designs:

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Rock Hound Station 1
Global Rockhound Community