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89-427: Bay Islands may refer to: Bay Islands Department , Honduras Southern Moreton Bay Islands , Queensland, Australia See also [ edit ] Bay of Islands Bay of Isles Island Bay, Wellington Little Bay Islands [REDACTED] Topics referred to by the same term This disambiguation page lists articles about distinct geographical locations with

178-400: A (usually small) angle. Sometimes multiple sets of layers with different orientations exist in the same rock, a structure called cross-bedding . Cross-bedding is characteristic of deposition by a flowing medium (wind or water). The opposite of cross-bedding is parallel lamination, where all sedimentary layering is parallel. Differences in laminations are generally caused by cyclic changes in

267-549: A British colony, attracted immediate attention in the United States, where it was universally regarded as a direct violation of the convention of July 5, 1850, known as the Clayton–Bulwer Treaty . This convention provides that "the governments of the United States and Great Britain, neither the one nor the other, shall over occupy, or fortify, or colonize, or assume or exercise any dominion over Costa Rica, Nicaragua,

356-424: A diagenetic structure common in carbonate rocks is a stylolite . Stylolites are irregular planes where material was dissolved into the pore fluids in the rock. This can result in the precipitation of a certain chemical species producing colouring and staining of the rock, or the formation of concretions . Concretions are roughly concentric bodies with a different composition from the host rock. Their formation can be

445-404: A few narrow passages, largely inaccessible, due to extensive coral reef growth. The island of Saint Helena has been described as a virtual extension of Roatán, since it is separated only by a long stretch of mangrove swamp . This island has a small elevated hill at its center, and is characterized by a large number of caves, most of which are located along a cliff on its western end. Guanaja

534-608: A large number of cool water springs in the Islands. Roatán features an intricate system of waterways on the south of the island, formed by the salt-water lagoons and drowned valleys on the island. The archipelago has been designated an Important Bird Area (IBA) by BirdLife International because it supports significant populations of white-crowned pigeons , chimney swifts and yellow-naped amazons . The islands were anciently known as Las Guanajas, from Guanaja , first seen by Christopher Columbus in his fourth and last voyage to

623-463: A particular sedimentary environment. Examples of bed forms include dunes and ripple marks . Sole markings, such as tool marks and flute casts, are grooves eroded on a surface that are preserved by renewed sedimentation. These are often elongated structures and can be used to establish the direction of the flow during deposition. Ripple marks also form in flowing water. There can be symmetric or asymmetric. Asymmetric ripples form in environments where

712-465: A red colour does not necessarily mean the rock formed in a continental environment or arid climate. The presence of organic material can colour a rock black or grey. Organic material is formed from dead organisms, mostly plants. Normally, such material eventually decays by oxidation or bacterial activity. Under anoxic circumstances, however, organic material cannot decay and leaves a dark sediment, rich in organic material. This can, for example, occur at

801-489: A rock is usually expressed with the Wentworth scale, though alternative scales are sometimes used. The grain size can be expressed as a diameter or a volume, and is always an average value, since a rock is composed of clasts with different sizes. The statistical distribution of grain sizes is different for different rock types and is described in a property called the sorting of the rock. When all clasts are more or less of

890-465: A sediment after its initial deposition. This includes compaction and lithification of the sediments. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and is characterized by bioturbation and mineralogical changes in the sediments, with only slight compaction. The red hematite that gives red bed sandstones their color is likely formed during eogenesis. Some biochemical processes, like

979-431: A sedimentary rock may have been present in the original sediments or may formed by precipitation during diagenesis. In the second case, a mineral precipitate may have grown over an older generation of cement. A complex diagenetic history can be established by optical mineralogy , using a petrographic microscope . Carbonate rocks predominantly consist of carbonate minerals such as calcite, aragonite or dolomite . Both

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1068-516: A small-scale property of a rock, but determines many of its large-scale properties, such as the density , porosity or permeability . The 3D orientation of the clasts is called the fabric of the rock. The size and form of clasts can be used to determine the velocity and direction of current in the sedimentary environment that moved the clasts from their origin; fine, calcareous mud only settles in quiet water while gravel and larger clasts are moved only by rapidly moving water. The grain size of

1157-952: A term for a fissile mudrock (regardless of grain size) although some older literature uses the term "shale" as a synonym for mudrock. Biochemical sedimentary rocks are created when organisms use materials dissolved in air or water to build their tissue. Examples include: Chemical sedimentary rock forms when mineral constituents in solution become supersaturated and inorganically precipitate . Common chemical sedimentary rocks include oolitic limestone and rocks composed of evaporite minerals, such as halite (rock salt), sylvite , baryte and gypsum . This fourth miscellaneous category includes volcanic tuff and volcanic breccias formed by deposition and later cementation of lava fragments erupted by volcanoes, and impact breccias formed after impact events . Alternatively, sedimentary rocks can be subdivided into compositional groups based on their mineralogy: Sedimentary rocks are formed when sediment

1246-417: A texture, only the average size of the crystals and the fabric are necessary. Most sedimentary rocks contain either quartz ( siliciclastic rocks) or calcite ( carbonate rocks ). In contrast to igneous and metamorphic rocks, a sedimentary rock usually contains very few different major minerals. However, the origin of the minerals in a sedimentary rock is often more complex than in an igneous rock. Minerals in

1335-425: A valuable indicator of the biological and ecological environment that existed after the sediment was deposited. On the other hand, the burrowing activity of organisms can destroy other (primary) structures in the sediment, making a reconstruction more difficult. Secondary structures can also form by diagenesis or the formation of a soil ( pedogenesis ) when a sediment is exposed above the water level. An example of

1424-503: Is deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension . This sediment is often formed when weathering and erosion break down a rock into loose material in a source area. The material is then transported from the source area to the deposition area. The type of sediment transported depends on the geology of the hinterland (the source area of the sediment). However, some sedimentary rocks, such as evaporites , are composed of material that form at

1513-523: Is 208 inhabitants per km , with the highest concentrations in Roatán and Utila. Roatán is the municipality with the most inhabitants, 29,636 in total. This municipality is followed by José Santos Guardiola, Guanaja, and Utila. The crude birth rate in the Bay Islands is 34.3. The mortality rate is 4.3, while the fertility rate is 3.7. The infant mortality rate is 24.7, while life expectancy in the islands

1602-465: Is 72.6 years (2001 census). In 2001, the migratory balance was 13,109 immigrants vs. 3,789 emigrants, leaving a net migratory balance of 9,320.34 residents. During the pre-Hispanic period, the Bay Islands were inhabited by the Pech people and other indigenous peoples. Archaeological remains found in the area, such as those on the island of Guanaja, show that these indigenous peoples originally inhabited all

1691-421: Is a structure where beds with a smaller grain size occur on top of beds with larger grains. This structure forms when fast flowing water stops flowing. Larger, heavier clasts in suspension settle first, then smaller clasts. Although graded bedding can form in many different environments, it is a characteristic of turbidity currents . The surface of a particular bed, called the bedform , can also be indicative of

1780-592: Is a violation of the treaty of July 5, 1850." Expostulations to this effect were at once addressed by the American government to that of the United Kingdom, and an elaborate correspondence was carried on through the years 1854–1856, between Mr. Buchanan, American minister in London, and Lord Clarendon, on the subject, but without any satisfactory result. The United Kingdom hastily augmented her naval forces on

1869-409: Is called bedding . Single beds can be a couple of centimetres to several meters thick. Finer, less pronounced layers are called laminae, and the structure a lamina forms in a rock is called lamination . Laminae are usually less than a few centimetres thick. Though bedding and lamination are often originally horizontal in nature, this is not always the case. In some environments, beds are deposited at

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1958-429: Is higher when the sedimentation rate is high (so that a carcass is quickly buried), in anoxic environments (where little bacterial activity occurs) or when the organism had a particularly hard skeleton. Larger, well-preserved fossils are relatively rare. Fossils can be both the direct remains or imprints of organisms and their skeletons. Most commonly preserved are the harder parts of organisms such as bones, shells, and

2047-491: Is mirrored by the broad categories of rudites , arenites , and lutites , respectively, in older literature. The subdivision of these three broad categories is based on differences in clast shape (conglomerates and breccias), composition (sandstones), or grain size or texture (mudrocks). Conglomerates are dominantly composed of rounded gravel, while breccias are composed of dominantly angular gravel. Sandstone classification schemes vary widely, but most geologists have adopted

2136-401: Is reduced. Sediments are typically saturated with groundwater or seawater when originally deposited, and as pore space is reduced, much of these connate fluids are expelled. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under the greatest strain, and the strained mineral is more soluble than the rest of

2225-540: Is the largest island, with a length of about 60 kilometres (40 mi) and a maximum width of 14 kilometres (9 mi) at its widest point. Roatán is characterized by its mountainous backbone, composed of hilltops that run west-to-east across the entire island. These hilltops are often crowned by outcrops of exposed metamorphic rocks such as marble , amphibolite , and serpentine . The island's southern coast has an abundance of deep ports and wide inlets, or 'bights', protected by reefs, while its northern coast is, save for

2314-493: Is the most stable, followed by feldspar , micas , and finally other less stable minerals that are only present when little weathering has occurred. The amount of weathering depends mainly on the distance to the source area, the local climate and the time it took for the sediment to be transported to the point where it is deposited. In most sedimentary rocks, mica, feldspar and less stable minerals have been weathered to clay minerals like kaolinite , illite or smectite . Among

2403-484: Is the second largest island and is even more mountainous than Roatán. Geographically it features a series of hills, the highest of which rises to over 350 m above sea level, which is the highest elevation present in the Bay Islands. Alluvial plains characterize the areas between the hills. Utila is third in size and is characterized by low mangrove swamps and a few small, low hills on its eastern end. The soils on this island are uncharacteristically fertile, perhaps owing to

2492-463: The history of life . The scientific discipline that studies the properties and origin of sedimentary rocks is called sedimentology . Sedimentology is part of both geology and physical geography and overlaps partly with other disciplines in the Earth sciences , such as pedology , geomorphology , geochemistry and structural geology . Sedimentary rocks can be subdivided into four groups based on

2581-682: The organic material of a dead organism undergoes chemical reactions in which volatiles such as water and carbon dioxide are expulsed. The fossil, in the end, consists of a thin layer of pure carbon or its mineralized form, graphite . This form of fossilisation is called carbonisation . It is particularly important for plant fossils. The same process is responsible for the formation of fossil fuels like lignite or coal. Structures in sedimentary rocks can be divided into primary structures (formed during deposition) and secondary structures (formed after deposition). Unlike textures, structures are always large-scale features that can easily be studied in

2670-471: The Bay Islands were the scene of frequent conflict between Spaniards and non-Spanish pirates. On the three main islands there live descendants of British settlers (mainly English ) who occupied the islands in the 18th century. By the mid-19th century, under the Wyke-Cruz treaty, many of the descendants of the white colonists of Great Britain changed their citizenship to Honduran after the country regained

2759-549: The Cayman Islands to work in agriculture. At present, the black inhabitants of the Bay Islands are not a genetically homogeneous group. Some black caribs with European ancestry and lighter skin refer to themselves as "browns" while referring to those with less European ancestry and darker skin as "colored". The economy of the Bay Islands depends directly on two sectors – tourism and fisheries, representing approximately 50% of gross island product and both closely linked to

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2848-501: The Dott scheme, which uses the relative abundance of quartz, feldspar, and lithic framework grains and the abundance of a muddy matrix between the larger grains. Six sandstone names are possible using the descriptors for grain composition (quartz-, feldspathic-, and lithic-) and the amount of matrix (wacke or arenite). For example, a quartz arenite would be composed of mostly (>90%) quartz grains and have little or no clayey matrix between

2937-637: The English settlers were in vain. Walker was captured by Captain Nowell Salmo, turned over to Honduran authorities, and executed on September 12, 1860. The population of the Bay Islands in 2010 was 49,158, according to the INE Population and Housing Census. It is the department with the smallest population in Honduras. 25,182 are women and 23,976 are men. The population density of the department

3026-530: The Mosquito shore, or any part of Central America." The matter was brought under the attention of Congress, and the committee of foreign relations of the U.S. senate, after a full consideration, reported "that the islands of Roatán, Bonacca, Utila, etc, in and near the bay of Honduras, constitute part of the territory of the republic of Honduras, and therefore form a part of Central America; and, in consequence, that any occupation of these islands by Great Britain

3115-544: The New World, on July 30, 1502. The Admiral named it 'Isle of Pines', and claimed it for Spain. It was from this island that he then encountered the coast of the American continent, on which he landed on the 14th of August following, at the point now called Punta Castilla de Trujillo . Pech Indians inhabited the islands, and they used boats to trade with Honduras, Yucatán, and (allegedly) Jamaica . Notwithstanding Spanish laws prohibiting slavery, governors interested in

3204-629: The Spanish, provoking an attempt by the Spaniards to drive them out of the colony. This attempt was initially unsuccessful, but in March 1650, the Spanish finally succeeded in retaking Port Royal. The events which followed, so far as they concern these islands, are thus narrated by the Bishop Pelaez: "On the 24th of September 1781, advices reached Truxillo, which were immediately communicated to

3293-489: The West India station, and her example was promptly followed by the United States; and, for a time, the peace of the two countries hung upon the discretion of a few naval commanders, acting under orders necessarily vague and indefinite. At this critical moment the government of Honduras despatched a minister to London, who took the ground that the question at issue was one that primarily concerned Honduras, and he demanded

3382-474: The accumulation or deposition of mineral or organic particles at Earth's surface , followed by cementation . Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment , and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from

3471-470: The activity of bacteria , can affect minerals in a rock and are therefore seen as part of diagenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sediments come under increasing overburden (lithostatic) pressure from overlying sediments. Sediment grains move into more compact arrangements, grains of ductile minerals (such as mica ) are deformed, and pore space

3560-470: The archipelago’s environment. All other activities provide services to these sectors, either directly as in the case of transportation or indirectly such as real estate and construction. The dynamic character of these sectors has led to accelerated growth over the last two decades, a phenomenon that has induced population growth rates approaching 8% annually, largely as a result of migration from various parts of Honduras and elsewhere. The Bay Islands serve "as

3649-399: The bottom of deep seas and lakes. There is little water mixing in such environments; as a result, oxygen from surface water is not brought down, and the deposited sediment is normally a fine dark clay. Dark rocks, rich in organic material, are therefore often shales. The size , form and orientation of clasts (the original pieces of rock) in a sediment is called its texture . The texture is

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3738-504: The cement and the clasts (including fossils and ooids ) of a carbonate sedimentary rock usually consist of carbonate minerals. The mineralogy of a clastic rock is determined by the material supplied by the source area, the manner of its transport to the place of deposition and the stability of that particular mineral. The resistance of rock-forming minerals to weathering is expressed by the Goldich dissolution series . In this series, quartz

3827-421: The cement to produce secondary porosity . At sufficiently high temperature and pressure, the realm of diagenesis makes way for metamorphism , the process that forms metamorphic rock . The color of a sedimentary rock is often mostly determined by iron , an element with two major oxides: iron(II) oxide and iron(III) oxide . Iron(II) oxide (FeO) only forms under low oxygen ( anoxic ) circumstances and gives

3916-639: The continents of the Earth's crust is extensive (73% of the Earth's current land surface), but sedimentary rock is estimated to be only 8% of the volume of the crust. Sedimentary rocks are only a thin veneer over a crust consisting mainly of igneous and metamorphic rocks . Sedimentary rocks are deposited in layers as strata , forming a structure called bedding . Sedimentary rocks are often deposited in large structures called sedimentary basins . Sedimentary rocks have also been found on Mars . The study of sedimentary rocks and rock strata provides information about

4005-572: The current is in one direction, such as rivers. The longer flank of such ripples is on the upstream side of the current. Symmetric wave ripples occur in environments where currents reverse directions, such as tidal flats. Mudcracks are a bed form caused by the dehydration of sediment that occasionally comes above the water surface. Such structures are commonly found at tidal flats or point bars along rivers. Secondary sedimentary structures are those which formed after deposition. Such structures form by chemical, physical and biological processes within

4094-663: The dominant particle size. Most geologists use the Udden-Wentworth grain size scale and divide unconsolidated sediment into three fractions: gravel (>2 mm diameter), sand (1/16 to 2 mm diameter), and mud (<1/16 mm diameter). Mud is further divided into silt (1/16 to 1/256 mm diameter) and clay (<1/256 mm diameter). The classification of clastic sedimentary rocks parallels this scheme; conglomerates and breccias are made mostly of gravel, sandstones are made mostly of sand , and mudrocks are made mostly of mud. This tripartite subdivision

4183-538: The feeble state of Honduras was left alone to contest these violent proceedings. Her government remonstrated energetically, but without obtaining redress; and finally, in 1844, the British government instructed Mr. Chatfield, consul-general, to apprise the Honduras authorities, that "when Col. Macdonald hauled down the flag of that state in Roatan, it was by order of the British government... no act of sovereignty followed on

4272-489: The field. Sedimentary structures can indicate something about the sedimentary environment or can serve to tell which side originally faced up where tectonics have tilted or overturned sedimentary layers. Sedimentary rocks are laid down in layers called beds or strata . A bed is defined as a layer of rock that has a uniform lithology and texture. Beds form by the deposition of layers of sediment on top of each other. The sequence of beds that characterizes sedimentary rocks

4361-404: The flow calms and the particles settle out of suspension . Most authors presently use the term "mudrock" to refer to all rocks composed dominantly of mud. Mudrocks can be divided into siltstones, composed dominantly of silt-sized particles; mudstones with subequal mixture of silt- and clay-sized particles; and claystones, composed mostly of clay-sized particles. Most authors use " shale " as

4450-543: The government at Comayagua, that certain Negroes and others, to the number of about 300 men, had constructed three forts at the entrance of the principal port of the island of Roatan, armed with 50 guns, and that three armed. Vessels cruised in the neighborhood, the object of the whole being to intercept the ships plying between the kingdom of Guatemala and Cuba. It was reported that these freebooters had 3000 barrels of provisions for their support, and that their object in holding

4539-485: The grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. The increased pressure and temperature stimulate further chemical reactions, such as the reactions by which organic material becomes lignite or coal. Lithification follows closely on compaction, as increased temperatures at depth hasten the precipitation of cement that binds the grains together. Pressure solution contributes to this process of cementation , as

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4628-510: The grains, a lithic wacke would have abundant lithic grains and abundant muddy matrix, etc. Although the Dott classification scheme is widely used by sedimentologists, common names like greywacke , arkose , and quartz sandstone are still widely used by non-specialists and in popular literature. Mudrocks are sedimentary rocks composed of at least 50% silt- and clay-sized particles. These relatively fine-grained particles are commonly transported by turbulent flow in water or air, and deposited as

4717-587: The host rock. For example, a shell consisting of calcite can dissolve while a cement of silica then fills the cavity. In the same way, precipitating minerals can fill cavities formerly occupied by blood vessels , vascular tissue or other soft tissues. This preserves the form of the organism but changes the chemical composition, a process called permineralization . The most common minerals involved in permineralization are various forms of amorphous silica ( chalcedony , flint , chert ), carbonates (especially calcite), and pyrite . At high pressure and temperature,

4806-464: The island with the largest deposit of serpentine among the Bay Islands. Morat, the smallest and flattest island, consists of just one ridge with two hills, which are composed mainly of sedimentary rocks, with some serpentinite intrusions. The Bay Islands have no rivers and a small number of streams, which usually end at mangrove swamps (of which there are plenty on the Islands). There are, however,

4895-408: The island. However, they were eventually forced to relocate, or they were captured, enslaved, or killed after the foreign occupation of the Bay Islands. Due to this, the islands were practically uninhabited by the year 1528. The archipelago began to be populated again by European people due to the arrival of English, French, and Dutch buccaneers who established their camps on the islands. From then on,

4984-525: The islands passed under the sovereignty of Honduras. Many of the English settlers disagreed with this resolution. They sought the help of American filibuster William Walker in order to put pressure on the British government to keep the islands. Walker who in 1857 had been deposed from the presidency of Nicaragua, by a Central American army, decided to assist them. Walker arrived in Honduras, and landed in Trujillo with one hundred men, but his efforts to help

5073-532: The islands rapidly declined. Diego Velasquez , governor of Cuba, in 1516 formally authorized several companies to trade in Indian slaves. In 1526, Hernán Cortés , who had conquered Mexico, marched to Trujillo to depose a rival conquistador from Cuba. The remaining Pech sought his protection, which Cortés provided. He drove away the slave traders, despite their licenses from the authorities in Cuba. William Claiborne

5162-400: The islands were under the jurisdiction of the state of Honduras. This state of things continued until May, 1830, when the superintendent of the British establishment of Belize, as a measure of coercion against the republic, which had refused to surrender certain runaway slaves, made a descent on Roatan and seized it on behalf of the British crown. The federal authorities remonstrated, and the act

5251-468: The islands's flat topography as well as volcanic tuffs and basalt lavas through coralline limestone . Barbareta, Morat, and the Hog Islands are all small and rugged. Barbareta can be distinguished by the fact that it contains numerous hills, the tallest one reaching a height of 143 m (469 ft), above sea level. Approximately one-third of Barbareta is covered by serpentinite, making it

5340-411: The islands. During the 18th century and the beginning of the 19th century, under British occupation, several contingents of black people arrived on these islands, among which three major groups stand out: (1) The Afro-colonial or French blacks, brought by the Spanish colonizers. (2) The Black Caribs or Garífunas . (3) The Anglo-Antilleans, known as English-speaking blacks, brought from Jamaica and

5429-435: The lithologies dehydrates. Clay can be easily compressed as a result of dehydration, while sand retains the same volume and becomes relatively less dense. On the other hand, when the pore fluid pressure in a sand layer surpasses a critical point, the sand can break through overlying clay layers and flow through, forming discordant bodies of sedimentary rock called sedimentary dykes . The same process can form mud volcanoes on

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5518-505: The major anchor site for Honduras's growing tourism industry, accounting for approximately 28% of all tourism arrivals." In 1990, an estimated 15,000 tourists came to the islands; by 1996 it was 60,000. According to the Honduran Institute of Tourism, during the year 2010 the islands of Roatán received 803,102 cruise shippers, 373,273 more than those received in 2009 (an increase of 86.8%). Total tourism receipts are estimated in

5607-450: The mineral dissolved from strained contact points is redeposited in the unstrained pore spaces. This further reduces porosity and makes the rock more compact and competent . Unroofing of buried sedimentary rock is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces the depth of burial, renewed exposure to meteoric water produces additional changes to the sedimentary rock, such as leaching of some of

5696-535: The neighborhood of US$ 55 million annually. Islander men frequently join on with the merchant marine or work on international cruise ships for several months of the year. This low-key existence began to change starting in the late 1960s, when tourists discovered the islands’ reefs, beaches, and funky culture. Since the late 1980s, the pace has picked up dramatically. The department is divided into five municipalities (municipalidades): Sedimentary rock Sedimentary rocks are types of rock that are formed by

5785-628: The northern coast of Honduras. These islands have been administered as a department of the Republic of Honduras since 1872. Located on the Caribbean Sea, not far east of the entrance to the Gulf of Honduras, they are clearly visible from the mountainous mainland. The total surface area of the islands is 250 km (97 sq mi). In 2013, they had an estimated population of 71,500 people. The islands comprise three separate groups: Roatán

5874-594: The permission of the state government of Honduras." "A number applied for and obtained the requisite permission, and received grants of land. But another portion, incited by one or two white men among them, appealed, as British subjects, to the superintendent of Belize, Col. Macdonald, who immediately visited the island, in the British sloop-of war Bover, ran down the flag of Honduras, and, seizing Col. Loustrelet and his soldiers, landed them near Truxillo, and threatened them with death if they ventured to return." The republic of Central America had meantime been dissolved, and

5963-438: The place of deposition. The nature of a sedimentary rock, therefore, not only depends on the sediment supply, but also on the sedimentary depositional environment in which it formed. As sediments accumulate in a depositional environment, older sediments are buried by younger sediments, and they undergo diagenesis. Diagenesis includes all the chemical, physical, and biological changes, exclusive of surface weathering, undergone by

6052-492: The port was to make it a refuge for their vessels, which were no longer allowed to go-to Jamaica… When this information reached Guatemala, Viceroy Galvez, "made arrangements to expel the intruders." The English seem to have made no other demonstration on the islands during the 18th century. They remained in the undisturbed occupation of Spain. "In 1821, when the Central American provinces achieved their independence,

6141-691: The proceedings of Macdonald. Meanwhile, the Cayman islanders continued to emigrate to Roatan, and, in 1848, the population numbered upward of 1,000. In 1850, the British organized the islands Roatan, Guanaja, Barbareta, Helena, Morat, and Utila into a colony under their rule, called the Bay Islands. A small party in the island favourable to British interests, was active in their efforts to secure English protection. "When visited by Capt. Mitchell, E. N., in 1850, he describes them as "electing their own magistrates, by universal suffrage," and "quite ignorant under what government they are placed." A Mr. William Fitzgibbon

6230-627: The processes responsible for their formation: clastic sedimentary rocks, biochemical (biogenic) sedimentary rocks, chemical sedimentary rocks, and a fourth category for "other" sedimentary rocks formed by impacts, volcanism , and other minor processes. Clastic sedimentary rocks are composed of rock fragments ( clasts ) that have been cemented together. The clasts are commonly individual grains of quartz , feldspar , clay minerals , or mica . However, any type of mineral may be present. Clasts may also be lithic fragments composed of more than one mineral. Clastic sedimentary rocks are subdivided according to

6319-480: The result of localized precipitation due to small differences in composition or porosity of the host rock, such as around fossils, inside burrows or around plant roots. In carbonate rocks such as limestone or chalk , chert or flint concretions are common, while terrestrial sandstones sometimes contain iron concretions. Calcite concretions in clay containing angular cavities or cracks are called septarian concretions . After deposition, physical processes can deform

6408-454: The rock a grey or greenish colour. Iron(III) oxide (Fe 2 O 3 ) in a richer oxygen environment is often found in the form of the mineral hematite and gives the rock a reddish to brownish colour. In arid continental climates rocks are in direct contact with the atmosphere, and oxidation is an important process, giving the rock a red or orange colour. Thick sequences of red sedimentary rocks formed in arid climates are called red beds . However,

6497-589: The same name. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Bay_Islands&oldid=972694386 " Category : Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Bay Islands Department The Bay Islands consist of eight islands and 53 small cays lying 15 kilometres (10 mi) to 60 kilometres (40 mi) off

6586-469: The same size, the rock is called 'well-sorted', and when there is a large spread in grain size, the rock is called 'poorly sorted'. The form of the clasts can reflect the origin of the rock. For example, coquina , a rock composed of clasts of broken shells, can only form in energetic water. The form of a clast can be described by using four parameters: Chemical sedimentary rocks have a non-clastic texture, consisting entirely of crystals. To describe such

6675-433: The sediment supply, caused, for example, by seasonal changes in rainfall, temperature or biochemical activity. Laminae that represent seasonal changes (similar to tree rings ) are called varves . Any sedimentary rock composed of millimeter or finer scale layers can be named with the general term laminite . When sedimentary rocks have no lamination at all, their structural character is called massive bedding. Graded bedding

6764-402: The sediment, producing a third class of secondary structures. Density contrasts between different sedimentary layers, such as between sand and clay, can result in flame structures or load casts , formed by inverted diapirism . While the clastic bed is still fluid, diapirism can cause a denser upper layer to sink into a lower layer. Sometimes, density contrasts occur or are enhanced when one of

6853-443: The sediment. They can be indicators of circumstances after deposition. Some can be used as way up criteria . Organic materials in a sediment can leave more traces than just fossils. Preserved tracks and burrows are examples of trace fossils (also called ichnofossils). Such traces are relatively rare. Most trace fossils are burrows of molluscs or arthropods . This burrowing is called bioturbation by sedimentologists. It can be

6942-464: The slave trade labeled the Pech Indians cannibals, hostile, and opposed to Christianity. Based on this information, Queen Isabella I of Spain issued a decree granting license to the Spaniards to capture and sell the islanders. Under this decree, Spanish slave traders from Cuba raided the Bay Islands continuously from the time of their discovery for the next 20 years. As a result, the population of

7031-535: The solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement , which are called agents of denudation . Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies ( marine snow ). Sedimentation may also occur as dissolved minerals precipitate from water solution . The sedimentary rock cover of

7120-459: The sovereignty of the latter state, with the reservation of trial by jury, freedom of conscience, etc., to the actual inhabitants. The principles of this convention were accepted by Honduras, but some of its details were viewed with disfavor by the Honduras congress, and it was returned to London for certain modifications. These changes were made, and the "colony of the Bay islands" ceased to exist, and

7209-453: The subsurface that is useful for civil engineering , for example in the construction of roads , houses , tunnels , canals or other structures. Sedimentary rocks are also important sources of natural resources including coal , fossil fuels , drinking water and ores . The study of the sequence of sedimentary rock strata is the main source for an understanding of the Earth's history , including palaeogeography , paleoclimatology and

7298-419: The surrender of the islands, equally as a measure of justice to that republic, and as a means of withdrawing a dangerous issue between the United States and the United Kingdom, upon which each had committed itself beyond the power of receding. This solution was regarded with favor by both parties, and a convention was entered into between the United Kingdom and Honduras, whereby the Bay islands were placed under

7387-610: The territory, and they officially separated from the British Empire. However, it would take several decades for them to assimilate into the Honduran population. A 2013 census determined that 11.41% of the population of the Bay Islands is white. However, it has been confirmed that more than 40% of the population on the island of Roatán is of foreign origin. These are mostly white Americans and French Canadians, as well as some European immigrants who have decided to buy properties on

7476-527: The three major types of rock, fossils are most commonly found in sedimentary rock. Unlike most igneous and metamorphic rocks, sedimentary rocks form at temperatures and pressures that do not destroy fossil remnants. Often these fossils may only be visible under magnification . Dead organisms in nature are usually quickly removed by scavengers , bacteria , rotting and erosion, but under exceptional circumstances, these natural processes are unable to take place, leading to fossilisation. The chance of fossilisation

7565-484: The whole proceeding... In spite of this protest, however, and backed by the guns of Bermuda , the authorities appointed by Sir Charles Grey were duly installed in the islands. Two years after this occupation, on March 20, 1852, a royal warrant was issued, constituting the islands a colony, under the title of "colony of the Bay islands," of which proclamation was made in Roatan, by Col. Wodehouse, superintendent of Belize, Aug. 10, 1852. The proclamation of these islands as

7654-404: The woody tissue of plants. Soft tissue has a much smaller chance of being fossilized, and the preservation of soft tissue of animals older than 40 million years is very rare. Imprints of organisms made while they were still alive are called trace fossils , examples of which are burrows , footprints , etc. As a part of a sedimentary rock, fossils undergo the same diagenetic processes as does

7743-518: Was chief justice, and acting chief magistrate. Some time in this year, a petition was drawn up by the British party, addressed to the governor of Jamaica, asking him to name magistrates and assume supreme authority in the island. Acting on this petition, Capt. Jolly in HMS Bermuda was sent to the islands. He called a meeting of the inhabitants, and declared them under the sovereignty of the United Kingdom. Chief Justice Fitzgibbon protested against

7832-484: Was disavowed by the British government." "The superintendents of Belize, however, seem to have kept a longing eye on the islands, and to have watched for a pretext to place them under their own jurisdiction. In 1838 their wishes were in part gratified. A party of liberated slaves...of the Grand Cayman islands , came to Roatan to settle. Col. Loustrelet, the commandant, apprised them that they could not do so without

7921-561: Was the first non-Spanish European to attempt settling the Bay Islands, after being granted a patent in 1638 to begin a colony on the island of Roatán. The English would be involved in the Bay Islands for the next two hundred years. Around this same period, Dutch, English, and French freebooters were leading raids on the Spanish in the Bay of Honduras. These raids largely avoided Claiborne's settlement. In 1642, English settlers from British Honduras (modern day Belize ) invaded and occupied Port Royal on Roatán. These same settlers also raided

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