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It was going to be a journey of a lifetime, a journey that millions dream of and never make, and I wanted to do justice to all those dreams

Autor /Adalbert Dodano /11.11.2011

I set out on a journey from my indigenous town Gdynia on the north cost of Poland. From the very beginning something was going wrong. Near the Swedish seashores I almost drifted on one of the peaks. The western border between Sweden and Norway mainly follows the Scandinavian mountain range. Its peaks, rising 1,000-2,000 meters (or some 3,000-7,000 feet) above sea level, were folded during the Silurian and Devonian periods but were raised during the Tertiary period. Sweden's largest rivers originate in these mountains. These information I remembered from my school years but didn't expect to see it.

The next day I sew the fiords of Norway. Just south of Ilulissat is the approximately 40 km long, 7km wide and 1200 metre deep ice fiord. With its up to 100 metre high and 500 to 30,000 year old icebergs it is is unique and breathtakingly impressive.

Few days later when I admired all North Sea's types of the coasts I sailed onto the Atlantic Ocean. On the middle of the ocean two tectonic plates meet and earthquakes occur.

I of course went through one. The plates consist of an outer layer of the Earth, the lithosphere, which is cool enough to behave as a more or less rigid shell. Occasionally the hot asthenosphere of the Earth finds a weak place in the lithosphere to rise buoyantly as a plume, or hotspot. Only lithosphere has the strength and the brittle behavior to fracture in an earthquake. The oceanic ridges are the asthenospheric spreading centers, creating new oceanic crust. Subduction zones appear as deep oceanic trenches. Most of the continental mountain belts occur where plates are pressing against one another.

I only have some photos of causes of earthquakes on the land but I can show them for the most interested students.

The burning of towns:

The houses destroyed:

The causes of earthquakes are also the seismic waves. Sound waves radiated from the earthquake as it ruptures. While most of the plate-tectonic energy driving fault ruptures is taken up by static deformation, up to 10% may dissipate immediately in the form of seismic waves.

The mechanical properties of the rocks that seismic waves travel through quickly organize the waves into two types. Compressional waves, also known as primary or P waves, travel fastest, at speeds between 1.5 and 8 kilometers per second in the Earth's crust. Shear waves, also known as secondary or S waves, travel more slowly, usually at 60% to 70% of the speed of P waves.

P waves shake the ground in the direction they are propagating, while S waves shake perpendicularly or transverse to the direction of propagation.

Although wave speeds vary by a factor of ten or more in the Earth, the ratio between the average speeds of a P wave and of its following S wave is quite constant. This fact enables seismologists to simply time the delay between the arrival of the P wave and the arrival of the S wave to get a quick and reasonably accurate estimate of the distance of the earthquake from the observation station. Just multiply the S-minus-P (S-P) time, in seconds, by the factor 8 km/s to get the approximate distance in kilometers.

The wave's that hit my yacht speed was 3 km per second but I was able to survive.

This wave took me to the coast of Hawaii islands. The biggest fame of those islands is its volcanic origin.

I saw the eruption of the volcano called Mauna Loa Volcano. Fissure eruption of this volcano produced a scoria cone and three lava flows; LBI, LBII and LBIII. LBI and LBIII are basaltic andesite and LBII is andesite. All three lavas are clastic in origin, although locally they resemble holocrystalline, blocky or aa lava. However remnant clast outlines can be identified at most localities, proximally and distally. Lavas in which obvious spatter fragments are observed have been called clastogenic lavas. They form in a similar manner to welded tuffs by syn- and post-depositional sintering and agglutination of hot juvenile fragments. In both cases the fragments are typically flattened, stretched and deformed.

Clastogenic lavas are produced by complete welding together of the clasts, but within individual flows varying degrees of welding may occur from agglutination (where clast outlines are still discernible) through to coalescence (homogeneous lava). Rapid accumulation of scoria and spatter is required to produce welded layers, and rapid growth of spatter cone and spatter ramparts may lead to over-steepening and instability. Sudden collapse of spatter cone, triggered for example, by associated syn-eruptive earthquakes, can lead to sliding and extensive non-particulate flow of the agglutinated and coalesced material resulting in the formation of clastogenic lavas. But people did not inhabit this volcano so the eruption was not drastic in results.

The eruption brought many hazards. During the volcanic eruption, fragments of lava or rock were blasted into the air by explosions and carried upward by a convecting column of hot gases. These fragments fell back to earth on and downwinded from their source vent to form a pyroclastic-fall or "ash" deposit. Pyroclastic-fall deposited, referred to as tephra, consist of combinations of pumice, scoria, dense-rock material, and crystals, that range in size from ash (64 millimeters). Eruptions that produce tephra range from short-lived weak ones that eject debris only a few meters into the air, to cataclysmic explosions that throw debris to heights of several tens of kilometers. Explosive eruptions that produce voluminous tephra deposits also commonly produce pyroclastic flows.

Close to an erupting vent, the main hazards to property posed by eruptions of tephra include high temperatures, burial, and impact of falling fragments; large falling blocks can kill or injure persons who cannot find shelter. Significant property damage can result from the weight of tephra, especially if ti is wet, and 20 centimeters or more of tephra may cause structures to collapse. Hot tephra falling near a volcano may set fire to forests and structures. Farther away, the chief danger to life is the effect of ash on the respiratory system. Even 5 centimeters of ash will stop the movement of most vehicles and disrupt transportation, communication, and utility systems. Machinery is especially susceptible to the abrasive and corrosive effects of ash. These effects, together with decreased visibility or darkness during an eruption, were not the only ones of this volcano, but the only visible ones.

The next island I saw was Hilo. The lock of food and fresh water forced me to wrapping up to the port. Beauty of scenery caused that decided to stay on her for some time. And yes just I myself here found.

I wolud like to end the story of my life with a quotation of Pukui and Handy:

"It is profoundly significant that the Hawaiians of Ka`u did not fear or cringe before, or hate, the power and destructive violence of Mauna Loa. They took unto them this huge mountain as their mother, and measured their personal dignity and powers in terms of its majesty and drama."

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