Agate has also been known to fill veins or cracks in volcanic or altered rock underlain by granitic intrusive masses.

The cities of Pompeii, Herculaneum, and Stabiae are buried in volcanic ash ( note: this traditional date has been challenged, and many scholars believe that the event occurred on October 24 ).

Exactly at the head of the gulf the great peak of the Cameroon, on a line of volcanic action continued by the islands to the south-west, has a height of, while Clarence Peak, in Fernando Po, the first of the line of islands, rises to over.

However, even Walter Alvarez has acknowledged that there were other major changes on Earth even before the impact, such as a drop in sea level and massive volcanic eruptions that produced the Indian Deccan Traps, and these may have contributed to the extinctions.

The impact origin of tektites has been questioned by some researchers ; they have observed some volcanic features in tektites not found in impactites.

Conan has " sullen ", " smoldering " and " volcanic " blue eyes with a black " square-cut mane ".

El Salvador has a long history of destructive earthquakes and volcanic eruptions.

If the rock is analyzed and found to be felsic but is metamorphic and has no definite volcanic protolith, it may be sufficient to simply call it a ' felsic schist '.

Western Basse-Terre has a rough volcanic relief while eastern Grande-Terre features rolling hills and flat plains.

Basse-Terre has a rough volcanic relief whilst Grande-Terre features rolling hills and flat plains.

Perlite is a volcanic rock that has been superheated into very lightweight expanded glass pebbles.

Wake Island is a volcanic island that has become an atoll

An atoll is an island formed from a coral reef that has grown on an eroded and submerged volcanic island.

While the volcanic ash has resulted in fertile soils, it makes agricultural conditions unpredictable in some areas.

A mountainous, volcanic island country, Japan has inadequate natural resources to support its growing economy and large population.

The south coast has two populated areas ; the bay of Komi and the ancient village of " Emporio ", inhabited since 1800 BC, and the site of the black volcanic beach of " Mavra Volia ", believed to have been created by the explosion of Santorini island in 1600 BC.

At the Villa of the Papyri at Herculaneum, apparently the villa of Caesar's father-in-law, the Greek library has been partly preserved in volcanic ash ; archaeologists speculate that a Latin library, kept separate from the Greek one, may await discovery at the site.

The Mediterranean-like climate, combined with the soil ( containing volcanic rock ), has made the region notable for its production of wines since the Roman period two thousand years ago.

However, it has been accepted that the eruption of Toba led to a volcanic winter with a worldwide decline in temperatures between, and up to in higher latitudes.

Its volcanic ash has created gray and black sand beaches in the north ( in particular between Anse Ceron and Anse des Gallets ), contrasting markedly from the white sands of Les Salines in the south.

A few researchers have favored Tektites originating from the Moon as volcanic ejecta, but this theory has lost much of its support over the last few decades.

The hills the Maremma can be divided into three areas: the area del Tufo ( tufo is a volcanic rock found in the area that has been used for thousands of years in construction ), the Colline Metallifere ( literally, " the hills that produce metals ") and the internal hills on the border with the Siena region.

The island also has numerous non-potable volcanic hot springs, including most notably the Bath Spring near Bath village, just south of the capital Charlestown.

The authors used a global circulation model, ModelE from the NASA Goddard Institute for Space Studies, which they noted " has been tested extensively in global warming experiments and to examine the effects of volcanic eruptions on climate.

Falling somewhere in a category between Einstein's theory and sand fleas -- difficult to see but undeniably there, nevertheless -- is the tropical green `` city '' of Islandia, a string of offshore islands that has almost no residents, limited access and an unlimited future.

For example, Scotland has more than 700 islands surrounding its mainland which constitute an archipelago.

The Senate also has 18 members, elected for a four year term by and from the chiefs of the islands.

It has 325 islands which cover an area of, with the Andaman Sea to the east between the islands and the coast of Burma.

The only airport in the islands is Vir Savarkar Airport in Port Blair, which has scheduled services to Kolkata and Chennai and Delhi, Banglore and Bhubaneswar.

Thus the " Aegean Area " has now come to mean the Archipelago with Crete and Cyprus, the Hellenic peninsula with the Ionian islands, and Western Anatolia.

The airfield also has a small commercial terminal handling scheduled and chartered passenger flights from the other islands in the Azores, Europe, Africa, and North America.

Every year since 1972 the BVI has hosted the Spring Regatta, which is a seven-day collection of sailing races throughout the islands.

The territory has also been recently relieving immigrants from many islands in Lesser Antilles.

There is limited natural fresh water resources ( except for a few seasonal streams and springs on Tortola, most of the islands ' water supply comes from wells and rainwater catchments ). It has strong ties to nearby US Virgin Islands and Puerto Rico.

It has numerous islands, and, above its mouth, it is broken by a bad series of rapids.

Sand carried by high winds has caused erosion on all islands, especially the windward ones.

The current north of the Canaries, has a cooling effect on the islands of Cape Verde, making the air temperature more bearable than it would expect in any case at this latitude.

At first, the islands of Cape Verde housed an extensive savanna and dry forest cover, but mostly it was removed to convert to agricultural land, which, together with the arid climate and rugged terrain, has led to a soil erosion and desertification widespread.

Once this islands were covered with savanna on the plains and arid shrubland on the mountainsides, but over 500 years of human habtitation, since colonisation by the Portuguese in the 15th century, nearly all the original vegetation has been cleared by widespread agriculture including the grazing of goats, sheep and cattle and the planting of imported crop species.

Although many Caribbean islands were initially populated by Amerindian groups such as the Arawaks, Tainos, and Caribs, no evidence of this has been found in the Cayman Islands.

It is the smallest of the four islands and has a central mountain chain reaching 860 meters at its highest.

The leading military power in the region, France has detachments on Mahoré and Réunion, and its Indian Ocean fleet sails the waters around the islands.

The cane toad ( Bufo marinus ), also known as the giant neotropical toad or marine toad, is a large, terrestrial true toad which is native to Central and South America, but has been introduced to various islands throughout Oceania and the Caribbean.

Because of its voracious appetite, the cane toad has been introduced to many regions of the Pacific and the Caribbean islands as a method of agricultural pest control.

1986 — In January 1986, following the rift between New Zealand and the USA in respect of the ANZUS security arrangements Prime Minister Tom Davis declared the Cook Islands a neutral country, because he considered that New Zealand ( which has control over the islands ' defence and foreign policy ) was no longer in a position to defend the islands.