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Beaches are loose deposits of sand, gravel or shells that cover the shoreline in many places.
They make up two-thirds of the world’s ice-free coastlines.
Beaches serve as buffer zones or shock absorbers that protect the coastline, sea cliffs or dunes from direct wave attack.
It is an extremely dynamic environment where sand, water and air are always in motion.
Beaches also provide important coastal recreational areas for a many people.
Fine-grained sand beaches tend to be quite flat.
Formation
Sandy beaches are soft shores that are formed by deposition of particles that have been carried by water currents from other areas.
The transported material is in part derived from the erosion of shores, but the major part is derived from the land and transported by rivers to the sea.
The two main types of beach material are quartz (silica) sands of terrestrial origin and carbonate sands of marine origin.
The carbonate sand is weathered from mollusc shells and skeletons of other animals.
Other material includes heavy minerals, basalt (volcanic origin) and feldspar.
The Wentworth Scale
Chester Keeler Wentworth was born in Aspen, Colorado, on May 7, 1891, one of five children of Frank Louis Wentworth and Anna Maria Keeler Wentworth. Chester graduated from the University of Chicago with an A.B. degree in geology in June 1918. Chester took his M.S. degree in 1921, and his Ph.D. in 1923, both at the University of Iowa. It was during his time as a student at Iowa that Chester’s unusual combination of aptitudes led to the achievement for which he is most widely known - the Wentworth scale for the classification of clastic sedimentary rocks.
Chester K. Wentworth, Fellow of The Geological Society of America since 1923, died in Hilo, Hawaii, on January 6, 1969, after several years of illness. He is survived by his widow, Juliette Oliveira Wentworth, and by two sons by a former marriage, Robert and Gordon. Another son, Thomas, was killed in France in 1944.
The original scale was devised in 1898 by the American sedimentary petrologist J.A. Udden was adapted (1922) by C.K. Wentworth, who expanded the definitions of the various grades to conform with actual usage by researchers; most sedimentologists have adopted the Udden scale with the Wentworth modifications.
Grain Size
Grain size scale, in sedimentology, division of a continuous range of particle sizes into a series of discrete groups. Several such scales have been devised for the purpose of standardizing terms and providing a basis for statistical analysis. On most scales, the finest particles are designated clay, followed by silt, sand, granules, gravel, pebbles, cobbles, and boulders. The size limits for each grade vary from scale to scale.
The Earthcache
This earthcache takes you to the only coastal city in Bosnia and Herzegovina. There are 24.5 kilometers of coastline constituting the only access to the country's sea in the Adriatic Sea.
To log this earthcache send us the answers of the following questions by email:
1. Using the Wentworth Scale in the listing classify the sediment according to grain size (Average size of stones).
2. Examine the sediment composition closely and tell me whether the sediment if mono (only one type of material) or multimineralic (more than one type of material)?
3. What is the color of the stones? Can you identify the name of the rocks?
4. Optional Task - Take a photo with the GPS showing the location or surrounding landscape.
According to the January 2013 guidelines: After sending the answers by email you can log it, if there is any problem we will contact you. If you do not send us the answers, your log will be deleted.
Plaze su labave deponije peska, šljunka ili granata koje pokrivaju obalu na mnogim mjestima.
One čine dve trećine svetskih bezalkoholnih obala.
Plaze sluze kao puferske zone ili amortizeri koji štite obalu, morske stene ili dine od direktnog talasnog napada.
To je izuzetno dinamično okruzenje u kome se uvek kreće pesak, voda i vazduh.
Plaze takođe pruzaju vazne obalne rekreativne oblasti za mnoge ljude.
Fino-zrnaste peščane plaze su prilično ravne.
Formacija
Peščane plaze su meke obale koje se formiraju deponovanjem čestica koje su nosile vodene struje iz drugih područja.
Prevezeni materijal djelimično potiče od erozije obale, ali najveći deo potiče iz zemlje i transportuje rijekama do mora.
Dva glavna tipa plaznog materijala su kvarcni (silicijumski) pesak zemaljskog porekla i karbonatni pesak morskog porekla.
Karbonatni pesak se izdvoji od školjki i skeleta drugih zivotinja.
Ostali materijali uključuju teške minerale, bazalt (vulkansko poreklo) i feldspar.
Skala Wentworth
Chester Keeler Wentworth je rođen u Aspenu, u Koloradu, 7. maja 1891. godine, jedan od pet djece Frank Louis Wentworth i Anna Maria Keeler Wentworth. Čester je diplomirao na Univerzitetu u Čikagu sa A.B. Diploma iz geologije u junu 1918. godine. Diplomirao 1921. i njegov doktorat. 1923. godine, i na Univerzitetu u Ajovi. U njegovom vremenu kao student u Ajovi, Chesterova neobična kombinacija sposobnosti dovela je do postignuća za koje je najpoznatiji - Wentworth skala za klasifikaciju klastičnih sedimentnih stijena.
Chester K. Wentworth, saradnik Geološkog društva Amerike od 1923. godine, umro je u Hilu, Havaji, 6. januara 1969. godine, posle nekoliko godina bolesti. Prezivio ga je njegova udovica, Juliette Oliveira Wentworth i dva sina bivšeg braka Robert i Gordon. Još jedan sin, Tomas, ubijen je u Francuskoj 1944. godine.
Originalna skala je izmišljena 1898. godine od strane američkog sedimentnog petrologusa J.A. Udden je adaptirao (1922) C.K. Wentworth, koji je proširio definicije različitih klasa u skladu sa stvarnom upotrebom od strane istrazivača; Većina sedimentologa usvojila je Udden skalu sa Wentworth modifikacijama.
Veličina Zrna
Skala veličine zrna, u sedimentologiji, podela kontinuiranog raspona veličine čestica u niz diskretnih grupa. Izrađeno je nekoliko takvih skala radi standardizacije uslova i pruzanja osnove za statističku analizu. Na većini vaga, najfinije čestice su označene gline, praćene muljem, peskom, granulama, šljunkom, šljunkom, cobbli i balderima. Granice veličine za svaki razred variraju od skale do skale.
Earthcache
Ova zemljakaša vas vodi do jedine primorske grada u Bosni i Hercegovini. Postoji 24,5 kilometara obale koje predstavljaju jedini pristup morskoj zemlji u Jadranskom moru.
Da biste prijavili ovu earthcache pošaljite nam odgovore na sledeća pitanja putem e-pošte:
1. Koristeći Wentworth Scale u listi klasificiraju sediment prema veličini zrna (Prosečna veličina kamena).
2. Ispitajte kompoziciju sedimenta i recite mi da li se sediment mono (samo jedna vrsta materijala) ili multimineralni (više od jedne vrste materijala)?
3. Koje su boje kamenja? Mozete li identifikovati ime kamena?
4. Opcionalni zadatak - Snimite fotografiju pomoću GPS-a koja prikazuje lokaciju ili okolinu.
Prema smernicama iz januara 2013. godine: Nakon slanja odgovora putem e-pošte, mozete je prijaviti, ukoliko postoji bilo kakav problem, kontaktirajte vas. Ako nam ne pošaljete odgovore, vaš dnevnik će biti izbrisan.
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