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94-674: The Tyrrhenian basin is located in a geologically complex portion of the Mediterranean Sea. The basin is partially encircled by several orogenic belts, including the Apennines to the northeast, the Alps to the north, and the Atlas Mountains to the southwest. It is also bounded by a convergent boundary and associated trench to the southeast. Deep reflection seismic lines near the trench clearly show oceanic lithosphere from

188-629: A mountain range consisting of parallel smaller chains extending c.  1,200 km (750 mi) the length of peninsular Italy . In the northwest they join the Ligurian Alps at Altare . In the southwest they end at Reggio di Calabria , the coastal city at the tip of the peninsula. Since 2000 the Environment Ministry of Italy, following the recommendations of the Apennines Park of Europe Project, has defined

282-599: A high diversity of flora and fauna. These mountains are one of the last refuges of the big European predators such as the Italian wolf and the Marsican brown bear , now extinct in the rest of Central Europe . The mountains lend their name to the Apennine peninsula that forms the major part of Italy. They are mostly verdant, although one side of the highest peak, Corno Grande , is partially covered by Calderone glacier ,

376-434: A high-energy subaerial environment like an alluvial fan. Overlying the conglomerate formation are oyster-bearing glauconitic sandstones deposited in a nearshore environment. Late Tortonian to Early Messinian calcareous ooze and claystone with benthic foram assemblages overlays the sandstone formation; this indicates that water depth increased, perhaps due to subsidence at the end of the syn-rift period. The boundary between

470-421: A netted appearance and have been referred to as chicken-wire anhydrite . Nodular anhydrite occurs as replacement of gypsum in a variety of sedimentary depositional environments. Massive amounts of anhydrite occur when salt domes form a caprock . Anhydrite is 1–3% of the minerals in salt domes and is generally left as a cap at the top of the salt when the halite is removed by pore waters. The typical cap rock

564-544: A picked corps) on special police duty with a detachment of twenty men from the Ravenna fleet. Snow lies on the highest peaks of the Apennines for almost the whole year. The range produces no minerals, but there are a considerable number of good mineral springs , some of which are thermal (such as Bagni di Lucca , Montecatini , Monsummano , Porretta, Telese), while others are cool (such as Nocera, Sangemini , Cinciano),

658-715: A series of tunnels have been constructed to conduct "the Bologna-Florence rail line", which is neither a single line nor a single tunnel. The Porrettana Line went into service in 1864, the Direttissima in 1934 and the High Speed in 1996. A few dozen tunnels support the three of them, the longest on the High-Speed Line being the Voglia Tunnel at 16.757 km (10.412 mi). The longest is on

752-701: A stone marks the top of the pass. In the vicinity are fragments of the old road and three ruins of former fortifications. At Carcare , the main roads connect with the upper Bormida valley (Bormida di Mallare) before turning west. The Scrivia , the Trebbia and the Taro , tributaries of the Po River , drain the northeast slopes. The range contains dozens of peaks. Toward the southern end the Aveto Natural Regional Park includes Monte Penna . Nearby

846-630: Is a technology complex in central and southern Italy from the Italian Middle Bronze Age (15th–14th centuries BC). In the mid-20th century the Apennine was divided into Proto-, Early, Middle and Late sub- phases , but now archaeologists prefer to consider as "Apennine" only the ornamental pottery style of the later phase of Middle Bronze Age (BM3). This phase is preceded by the Grotta Nuova facies (central Italy) and by

940-435: Is a salt, topped by a layer of anhydrite, topped by patches of gypsum, topped by a layer of calcite. Interaction of anhydrite with hydrocarbons at high temperature in oil fields can reduce sulfate ( SO 4 ) into hydrogen sulfide (H 2 S) with a concomitant precipitation of calcite . The process is known as thermochemical sulfate reduction (TSR). Anhydrite has been found in some igneous rocks , for example in

1034-606: Is at about 3,200 m (10,500 ft), leaving the Apennines below it, except for the one remaining glacier. Snow may fall from October to May. Rainfall increases with latitude. The range's climates, depending on elevation and latitude, are the Oceanic climate and Mediterranean climate . The mammal fauna is mainly composed of Italian wolves (endemic), Corsican hare , badgers , weasels , foxes , marmots , Etruscan shrew , Crested porcupine , European snow vole and Apennine shrews (endemic), Marsican brown bears (endemic),

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1128-471: Is believed to be deposited after the end of rifting due to its subhorizontal seismic reflection profile. The basement rock in the Vavilov Basin consists of strongly serpentinized peridotite with both high and low-temperature phases of deformation. The peridotite is overlain by 120 meters of tholeiitic pillow basalt containing carbonate-filled veins. Nannofossils and planktonic foraminifera within

1222-629: Is deep and separates the Apennines on the left bank from a lesser range, the Tuscan Anti-Apennines (Sub-Apennines) on its right. The Apennine System forms an irregular arc with centers of curvature located in the Tyrrhenian Sea. The northern and southern segments comprise parallel chains that can be viewed as single overall mountain ridges, such as the Ligurian Mountains. The center, being thicker and more complex,

1316-461: Is deposited if the temperature is above 40 °C (104 °F). This is one method by which the mineral has been prepared artificially and is identical with its mode of origin in nature. The mineral is common in salt basins . Anhydrite occurs in a tidal flat environment in the Persian Gulf sabkhas as massive diagenetic replacement nodules . Cross sections of these nodular masses have

1410-663: Is geologically divided into an inner and an outer arc with regard to the centers of curvature. The geologic definition, however, is not the same as the geographic. Based on rock type and orogenic incidents, the northern segment of the arc is divided into the Outer Northern Apennines (ONA) and the Inner Northern Apennines (INA). The Central Apennines are divided into the Umbrian–Marchean ( Appennino umbro-marchigiano ) or Roman Apennines in

1504-470: Is mainly grasslands of the Montane grasslands and shrublands biome; with Temperate broadleaf and mixed forests, and Mediterranean forests, woodlands, and scrub below it. The tree line in the Apennines can be found in the range 1,600 m (5,200 ft) to 2,000 m (6,600 ft). About 5% of the map area covered by the Apennines is at or above the tree line—or in the treeline ecotone. The snow line

1598-510: Is most frequently found in evaporite deposits with gypsum; it was, for instance, first discovered in 1794 in a salt mine near Hall in Tirol . In this occurrence, depth is critical since nearer the surface anhydrite has been altered to gypsum by absorption of circulating ground water. From an aqueous solution , calcium sulfate is deposited as crystals of gypsum, but when the solution contains an excess of sodium or potassium chloride , anhydrite

1692-544: Is part of the Monti Sibillini , incorporated into Parco Nazionale dei Monti Sibillini . Further north is the parco naturale regionale della Gola della Rossa e di Frasassi  [ it ] , in which are the Gola della Rossa ("Red Gorge") and Frasassi Caves . Still further north is Parco Sasso Simone e Simoncello. The Italian Park Service calls it the "green heart" of Italy. The region is heavily forested , such as

1786-514: Is that it derives from the Celtic penn , 'mountain', 'summit': A-penn-inus , which could have been assigned during the Celtic domination of north Italy in the 4th century BC or before. The name originally applied to the north Apennines. However historical linguists have never found a derivation with which they all agree. Wilhelm Deecke said: "[…] its etymology is doubtful but some derive it from

1880-566: Is the Bocca Serriola Pass in northern Umbria , which links Fano and Città di Castello . The Tiber River at Rome flows from Monte Fumaiolo in the Tuscan-Romagnol Apennine from northeast to southwest, projecting into the Tyrrhenian Sea at right angles to the shore. The upper Tiber, however, flows from northwest to southeast, gradually turning through one right angle clockwise. The northern Tiber Valley

1974-780: Is the Italian sparrow . The reasons for this choice are related to the fact that the Italian wolf, which inhabits the Apennine Mountains and the Western Alps , features prominently in Latin and Italian cultures, such as in the legend of the founding of Rome . In Italy the transhumance took place mainly starting from the Abruzzi Apennines, moving both towards the Tuscan and Lazio Maremma and above all towards

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2068-399: Is the easternmost point on the margin where pre-rift, syn-rift, and post-rift sediments can be clearly discerned on seismic reflection profiles. A drill core to the base of the syn-rift sediments revealed 533 meters of thinly-bedded, calcareous, siltstone and sandstone with dispersed detrital gypsum grains and anhydrite nodules. The entire sequence is reversely magnetized, which when placed in

2162-421: Is the highest point of Ligurian Apennines, Monte Maggiorasca at 1,800 m (5,900 ft). The main and only feasible overland route connecting the coastal plain of Liguria to the north Italian plain runs through Bocchetta di Altare. It has always been of strategic importance. Defenders of north Italy have had to control it since ancient times, as the various fortifications placed there testify. Trenitalia ,

2256-537: Is widely agreed that extension in the Tyrrhenian basin began in the late Miocene , as shown by the recognition in seismic reflection profiles of pre-evaporitic (i.e. pre-Messinian) sediments in the western Tyrrhenian and by age estimates based on the overall lithospheric thickness, basement relief, and heat flow. K-Ar dating of peripheral oceanic basalts, drilled at the southeast edge of the Vavilov plain, estimates

2350-608: The African Plate beneath the Eurasian Plate . Similar to other back-arc basins, the Tyrrhenian basin displays a shallowing of the Moho discontinuity towards the central part of the basin, a Wadati Benioff zone , abnormally high heat flow (exceeding 200 mW/m in some places), and an active volcanic belt on the arc-ward edge of the basin. Tyrrhenian basement rocks consist of late Paleozoic granites derived from

2444-515: The Alpine system . Prior to the explosion of data on the topic from about the year 2000, many authors took the approach that the Apennines had the same origin as the Alps. Even today, some authors use the term Alpine-Apennine system. They are not, however, the same system and did not have the same origin. The Alps were millions of years old before the Apennines rose from the sea. The northward movement of

2538-628: The Aterno from the north-west and the Gizio from the south-east, is more important; and so is the Sangro . The central Apennines are crossed by the railway from Rome to Pescara via Avezzano and Sulmona: the railway from Orte to Terni (and thence to Foligno ) follows the Nera valley; while from Terni a line ascends to the plain of Rieti, and thence crosses the central chain to Aquila, whence it follows

2632-673: The Eurasian eagle-owl There are also numerous amphibians such as the Apennine yellow-bellied toad (endemic), the Italian cave salamander (endemic), the Italian newt (endemic), the Italian stream frog (endemic) and the Spectacled salamander (endemic), the Italian tree frog (endemic), the Agile frog , the Italian edible frog (endemic), the Common toad , the Balearic green toad ,

2726-684: The European fallow deer , the European mouflon and the Pyrenean chamois . There are also numerous birds such as the golden eagle , the Bonelli's eagle , the Eurasian goshawk , the hoopoe , the hawk , the European roller , the White-backed woodpecker , the European green woodpecker , the Alpine chough , the Egyptian vulture , the European nightjar , the Italian sparrow (endemic) and

2820-586: The Hercynian orogeny . Basement rocks in the southeastern portion of the basin were reactivated during the Alpine orogeny while those to the northwest were undisturbed. The Upper Sardinia Margin is a fault-bounded passive margin located northwest of the Vavilov Basin. Seismic reflection surveys across the Upper Sardinia Margin exhibit a stratigraphic geometry suggestive of pre-rift, syn-rift, and post-rift sequences. Drill cores penetrating to

2914-643: The Ligurian Sea in the Gulf of Genoa , from about Savona below the upper Bormida River valley to about La Spezia ( La Cisa pass ) below the upper Magra River valley. The range follows the Gulf of Genoa separating it from the upper Po Valley . The northwestern border follows the line of the Bormida River to Acqui Terme . There the river continues northeast to Alessandria in the Po Valley , but

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3008-703: The Majella Massif. Among them are two national parks: Gran Sasso e Monti della Laga National Park and Majella National Park ; and the Regional Park of the Monti Simbruini. Gran Sasso contains Corno Grande , the highest peak of the Apennines (2912 m). Other features between the western and central ranges are the plain of Rieti , the valley of the Salto, and the Lago Fucino ; while between

3102-838: The Northern spectacled salamander (endemic), the Fire salamander , the Smooth newt , the Alpine newt , and the Italian crested newt . The reptile fauna is mainly composed of suc as the Italian Aesculapian snake (endemic), the Dice snake , the Green whip snake , the Aesculapian snake , the Smooth snake , the Vipera ursinii , the Vipera aspis , the Italian wall lizard (endemic),

3196-486: The Po Valley in northern Italy. Compressional forces have been acting from north to south in the Alps and from south to north in the Apennines, but instead of being squeezed into mountains the valley has been subsiding at 1 to 4 mm (0.16 in) per year since about 25 mya , before the Apennines existed. It is now known to be not an erosional feature, but is a filled portion of the Adriatic Trench, called

3290-513: The Podarcis muralis , the European green lizard . Notable Apennine freshwater fishes are the Brook lamprey (endemic), Lombardy lamprey , Italian bleak (endemic), Horse barbel (endemic), Eurasian carp , Scardola scardafa (endemic), European perch , Chubius Chub , Tench and Northern pike . The Italian wolf is the national animal of Italy, while the national bird of the country

3384-1234: The Pollino National Park , the Vesuvius National Park , the Cilento, Vallo di Diano and Alburni National Park , the Appennino Lucano - Val d'Agri - Lagonegrese National Park , the Sila National Park , the Aspromonte National Park . Important rivers originate from the Apennines are the Panaro , the Secchia , the Reno , the Marecchia , the Rubicon , the Metauro , the Arno , the Tiber ,

3478-425: The Savio , the Nera , the Velino , the Tronto , the Aterno-Pescara , the Aniene , the Liri , the Sangro and the Volturno . Among the lakes of glacial origin of the Alpine type is Lago di Pilato . The Apennines were created in the Apennine orogeny beginning in the early Neogene (about 20 mya , the middle Miocene ) and continuing today. Geographically they are partially (or appear to be) continuous with

3572-399: The Tavoliere delle Puglie . The Apennines are to some extent covered with forests, though these were probably more extensive in classical times ( Pliny mentions especially pine , oak and beech woods, Hist. Nat . xvi. 177); they have indeed been greatly reduced in comparatively modern times by indiscriminate timber-felling, and though serious attempts at reforestation have been made by

3666-407: The intrusive dioritic pluton of El Teniente, Chile and in trachyandesite pumice erupted by El Chichón volcano, Mexico. The name anhydrite was given by A. G. Werner in 1804, because of the absence of water of crystallization, as contrasted with the presence of water in gypsum. Some obsolete names for the species are muriacite and karstenite; the former, an earlier name, being given under

3760-409: The orogeny . These extend in a northwest–southeast direction from the River Tronto to the River Sangro , which drain into the Adriatic . The coastal hills of the east extend between San Benedetto del Tronto in the north and Torino di Sangro in the south. The eastern chain consists mainly of the southern part of the Monti Sibillini , the Monti della Laga , the Gran Sasso d'Italia Massif and

3854-401: The volcanic arc of the convergent system. The volcanism associated with these islands occurs at the northeast closure of the downgoing slab and began approximately during the late Pliocene to early Pleistocene (1.5–1.7 Ma). The Tyrrhenian basin lies to the northwest of the Aeolian Islands and represents a back-arc basin formed from tensional forces associated with the northwest subduction of

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3948-463: The Adriatic foredeep after its function as a subduction zone was discovered. Anhydrite Anhydrite , or anhydrous calcium sulfate , is a mineral with the chemical formula CaSO 4 . It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry . It is not isomorphous with the orthorhombic barium ( baryte ) and strontium ( celestine ) sulfates, as might be expected from

4042-421: The African Plate and its collision with the European Plate then caused the Alpine Orogeny , beginning in the late Mesozoic. The band of mountains created extends from Spain to Turkey in a roughly east–west direction and includes the Alps. The Apennines are much younger, extend from northwest to southeast, and are not a displacement of the Alpine chain. The key evidence of the difference is the geologic behavior of

4136-479: The African plate flexing beneath Calabria to join a seismogenic slab that extends down to 500 km beneath the Tyrrhenian basin. Between the upper slope of the trench and Calabria are a number of small fore-arc basins that developed through extensional listric faulting during the Tortonian . These basins subsequently subsided between the late Pliocene and Quaternary and are now infilled with mélange . The Aeolian Islands north of Calabria and Sicily represent

4230-538: The Apennine range, and so are Cilento hills on the west. On the converse the promontory of Mount Gargano , on the east, is completely isolated, and so are the Campanian volcanic arc near Naples . The district is traversed from north-west to south-east by the railway from Sulmona to Benevento and on to Avellino , and from south-west to northeast by the railways from Caianello via Isernia to Campobasso and Termoli, from Caserta to Benevento and Foggia, and from Nocera Inferiore and Avellino to Rocchetta Sant'Antonio,

4324-426: The Apennines System to include the mountains of north Sicily , a total distance of 1,500 kilometres (930 mi) . The system forms an arc enclosing the east of the Ligurian and Tyrrhenian seas. The Apennines conserve some intact ecosystems that have survived human intervention. In these are some of the best-preserved forests and montane grasslands in Europe, now protected by national parks and, within them,

4418-435: The Calabrian southern Apennine Mountains extend along the northern coast of Sicily (the Sicilian Apennines, Italian Appennino siculo )— Pizzo Carbonara (6,493 feet (1,979 m)) being the highest peak. The number of vascular plant species in the Apennines has been estimated at 5,599. Of these, 728 (23.6%) are in the treeline ecotone . Hemicryptophytes predominate in the entire Apennine chain. The tree line ecotone

4512-434: The Direttissima, the Great Apennine Tunnel, which at 18.5 kilometres (11.5 miles) is the longest entirely within Italy, although the Simplon Tunnel , which connects Italy and Switzerland, is longer. Automobile traffic is carried by the Autostrada del Sole, Route A1, which goes through numerous shorter tunnels, bypassing an old road, originally Roman, through Futa Pass. In December 2015, a new Route A1 called Variante di Valico

4606-446: The Greek Pindus Mountains from the same root, but *kwen- < *kwi- is not explained by any rule. By some, English pin , as well as pen and Latin pinna or penna , 'feather' (in the sense of the horn of the quill), have been connected to the name. This view has the word originating in Latium inconsistently with the theory of the northern origin. None of these derivations is accepted unquestionably. The Apennine culture

4700-434: The Greeks and Sicilians with timber for shipbuilding. The railway from South Eufemia to Catanzaro and Catanzaro Marina crosses the isthmus, and an ancient road may have run from Squillace to Monteleone. The second group extends to the south end of the Italian Peninsula , culminating in the Aspromonte (1,960 metres (6,420 ft)) to the east of Reggio di Calabria . In both groups the rivers are quite unimportant. Finally,

4794-411: The Late Bronze Age as it is defined in Greece and the Aegean. The people of the Apennine culture were alpine cattle herdsmen grazing their animals over the meadows and groves of mountainous central Italy. They lived in small hamlets located in defensible places. On the move between summer pastures they built temporary camps or lived in caves and rock shelters. Their range was not necessarily confined to

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4888-505: The Ligurian-Celtish Pen or Ben , which means mountain peak." A large number of place names seem to reflect pen : Penarrig, Penbrynn, Pencoid, Penmon, Pentir, etc. or ben : Beanach, Benmore, Benabuird, Benan, Bencruachan, etc. In one derivation Pen/Ben is cognate with Old Irish cenn , 'head', but an original *kwen- would be required, which is typologically not found in languages that feature labio-velars . Windisch and Brugmann reconstructed Indo-European *kwi- , deriving also

4982-415: The Protoapennine B facies (southern Italy) and succeeded by the Subapennine facies of 13th-century ("Bronzo Recente"). Apennine pottery is a burnished ware incised with spirals, meanders and geometrical zones, filled with dots or transverse dashes. It has been found on Ischia island in association with LHII and LHIII pottery and on Lipari in association with LHIIIA pottery, which associations date it to

5076-487: The Riserva Naturale Statale Gola del Furlo, where Furlo Pass on the Via Flaminia is located. Both the Etruscans and the Romans constructed tunnels here. The Abruzzi Apennines, located in Abruzzo , Molise and southeastern Lazio , contain the highest peaks and most rugged terrain of the Apennines. They are known in history as the territory of the Italic peoples first defeated by the city of Rome . Coincidentally they exist in three parallel folds or chains surviving from

5170-410: The Romans used the Via Flaminia between Rome and Rimini . The montane distance between Florence in Tuscany and Bologna in Emilia-Romagna is shorter, but exploitation of it required the conquest of more rugged terrain, which was not feasible for the ancients. Railway lines were constructed over the mountains in the early 19th century but they were of low capacity and unimprovable. Since 1856,

5264-411: The Sele—joined by the Negro and Calore—on the west, and the Bradano , Basento , Agri, Sinni on the east, which flow into the gulf of Taranto; to the south of the last-named river there are only unimportant streams flowing into the sea east and west, inasmuch as here the width of the peninsula diminishes to some 64 kilometres (40 mi). The railway running south from Sicignano to Lagonegro, ascending

5358-448: The Tunisian Atlas thrust belt. 39°56′N 12°14′E  /  39.933°N 12.233°E  / 39.933; 12.233 Apennines The Apennines or Apennine Mountains ( / ˈ æ p ə n aɪ n / AP -ə-nyne ; ‹See Tfd› Greek : Ἀπέννινα ὄρη or Ἀπέννινον ὄρος; Latin : Appenninus or Apenninus Mons   – a singular with plural meaning; Italian : Appennini [appenˈniːni] ) are

5452-439: The Tuscan Apennines. They extend to the upper Tiber River . The highest point is Monte Cimone at 2,165 m (7,103 ft). A separate branch, the Apuan Alps , goes southwest, bordering the coast south of La Spezia . Whether they are to be considered part of the Apennines is a matter of opinion; certainly, they are part of the Apennine System. Topographically only the valley of the River Serchio , which running parallel to

5546-437: The back-arc region. However, if the velocity of slab rollback and trench retreat exceeds that of the overriding plate, then back-arc extension will occur. The Pliocene-Pleistocene changes in Tyrrhenian back-arc extension may have also been influenced by the adjacent Adriatic and Sicilian forelands. These sectors were not thinned by rifting and are characterized by normal continental lithosphere. During its southeastward migration,

5640-410: The base of the syn-rift sediments identified a transgressive sequence related to subsidence of the continental crust during the rifting stage of the Tyrrhenian Basin opening. At the base of the syn-rift sequence are 60 meters of Tortonian conglomerate with subrounded clasts derived from metamorphosed carbonate and quartzitic basement. It is inferred that this conglomerate formation was deposited in

5734-401: The beginning of extension to be 7.3 ± 1.3 Ma. Basalts recovered near the spreading center, in middle of the Vavilov plain, yielded ages of 3.4–3.6 Ma. This means that back-arc extension in this part of the basin occurred approximately between the late Tortonian and the middle Pliocene. However, in the Marsili plain, the oldest basaltic crust was found to be 2.1 Ma. This lower age limit, along with

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5828-476: The beta factor, is estimated to be 3.3 for the Tyrrhenian basin. Although there are numerous petroleum plays in mainland Italy and the northern Ionian Sea , the potential for hydrocarbon accumulation in most of the Tyrrhenian basin is very poor. This is primarily due to the basin's high geothermal gradient which pushes the oil window to very shallow depths where structural and stratigraphic traps are uncommon. There is, however, active hydrocarbon exploration on

5922-403: The carbonate veins constrain the age of emplacement between 3.1 and 3.6 Ma. Immediately above the basalt is a 100-meter-thick section of Pleistocene sedimentary cover, consisting primarily of nannofossil-rich mud with occasional reworked volcanogenic debris. The basement rock of the Marsili Basin is vesicular basalt. Due to the abundance (10–30% of rock volume) and size (up to 3 or 4 mm) of

6016-450: The central Tyrrhenian basin. The full spreading rate of the Tyrrhenian basin has been estimated to be 3–5 cm/yr based on kinematic reconstructions and magnetostratigraphy. This is a relatively slow spreading rate when compared to spreading rates in other back-arc basins like the East Scotia basin (5–7 cm/yr) and the Manus basin (13 cm/yr). The ratio between the initial crustal thickness and final crustal thickness, also known as

6110-461: The central and eastern ranges are the valleys of Aquila and Sulmona . The chief rivers on the west are the Nera , with its tributaries the Velino and Salto, and the Aniene , both of which fall into the Tiber. On the east there is at first a succession of small rivers which flow into the Adriatic , from which the highest points of the chain are some 20   km distant, such as the Tronto , Tordino, Vomano and others. The Pescara , which receives

6204-411: The chemical formulas. Distinctly developed crystals are somewhat rare, the mineral usually presenting the form of cleavage masses. The Mohs hardness is 3.5, and the specific gravity is 2.9. The color is white, sometimes greyish, bluish, or purple. On the best developed of the three cleavages, the lustre is pearly; on other surfaces it is glassy. When exposed to water, anhydrite readily transforms to

6298-480: The coast turns and exits into the Tyrrhenian Sea north of Pisa , separates the Apuan Alps from the Apennines; geologically the rock is of a slightly different composition, marble . The Roman marble industry was centered at Luna , and is now active in Carrara . As the Tuscan Apennines divide the peninsula between the Po Valley and the plains and hills of Tuscany and Lazio , transportation over them has been used to achieve political and economic unity. Historically

6392-548: The context of the adjacent stratigraphy, suggests that it was deposited during the reversed polarity event of the Gilbert epoch (between 4.79 and 5.41 Ma). The environment of deposition for this section is uncertain; however, due to the presence of thin, well-graded layers and a lack of marine fossils, it is possible that the formation was deposited in a closed lacustrine setting. Overlaying the syn-rift sediments are 200 meters of Pliocene to Pleistocene hemipelagic marine sediment with intermittent volcanic glass. This sediment layer

6486-416: The first episode of subduction, thinned continental lithosphere underlying the Apenninic margin subducted beneath the Eurasian plate. However, in the second episode of subduction, it was instead Ionian oceanic lithosphere that was involved in subduction. A transition from continental to oceanic lithosphere subduction could explain the late onset of arc volcanism (2-1.5 Ma) as well as the lack of arc volcanism in

6580-423: The government, much remains to be done. They also furnish considerable summer pastures, especially in the Abruzzi : Pliny ( Hist. Nat . xi. 240) praises the cheese of the Apennines. In the forests Italian wolves were frequent, and still are found, the flocks being protected against them by large sheep-dogs; Marsican brown bears , however, which were known in Roman times, have almost entirely disappeared. Nor are

6674-429: The hills; their pottery has been found on the Capitoline Hill in Rome as well as on the islands mentioned above. The Apennines are divided into three sectors: northern ( Appennino settentrionale ), central ( Appennino centrale ), and southern ( Appennino meridionale ). A number of long hiking trails wind through the Apennines. Of note is European walking route E1 coming from northern Europe and traversing

6768-572: The impression that the substance was a chloride (muriate). A peculiar variety occurring as contorted concretionary masses is known as tripe-stone, and a scaly granular variety, from Volpino , near Bergamo , in Lombardy , as vulpinite; the latter is cut and polished for ornamental purposes. A semi-transparent light blue-grey variety from Peru is referred to by the trade name angelite . The Catalyst Science Discovery Centre in Widnes, England , has

6862-645: The junction for Foggia, Spinazzola (for Barletta, Bari, and Taranto ) and Potenza. Roman roads followed the same lines as the railways: the Via Appia ran from Capua to Benevento, whence the older road went to Venosa and Taranto and so to Brindisi , while the Via Traiana ran nearly to Troia (near Foggia) and thence to Bari. The valley of the Ofanto , which runs into the Adriatic close to Barletta , marks

6956-579: The lengths of the northern and central Apennines. The Grand Italian Trail begins in Trieste and after winding through the Alpine arc traverses the entire Apennine system, Sicily and Sardinia. The northern Apennines consist of three subchains : the Ligurian ( Appennino ligure ), Tuscan-Emilian ( Appennino tosco-emiliano ), and Umbrian Apennines ( Appennino umbro ). The Ligurian Apennines border

7050-435: The more commonly occurring gypsum , (CaSO 4 ·2H 2 O) by the absorption of water. This transformation is reversible, with gypsum or calcium sulfate hemihydrate forming anhydrite by heating to around 200 °C (400 °F) under normal atmospheric conditions. Anhydrite is commonly associated with calcite , halite , and sulfides such as galena , chalcopyrite , molybdenite , and pyrite in vein deposits. Anhydrite

7144-649: The mountains bend away to the southeast. The upper Bormida can be reached by a number of roads proceeding inland at a right angle to the coast southwest of Savona , the chief one being the Autostrada Torino-Savona. They ascend to the Bocchetta di Altare , sometimes called Colle di Cadibona , 436 m (1,430 ft), the border between the Ligurian Alps along the coast to the west and the Ligurian Apennines. A bronze plaque fixed to

7238-587: The north and the Abruzzi Apennines ( Appennino abruzzese ) in the south. It extends from Bocca Serriola pass in the north to Forlì pass in the south. The west border of the Umbria-Marche Apennines (or Appennino umbro-marchigiano )) runs through Cagli . They extend south to the Tronto River, the south border of the ONA. The highest peak, Monte Vettore , at 2,478 m (8,130 ft),

7332-649: The northern termination of the first range of the Lucanian Apennines (now Basilicata ), which runs from east to west, while south of the valleys of the Sele (on the west) and Basento (on the east)—which form the line followed by the railway from Battipaglia via Potenza to Metaponto —the second range begins to run due north and south as far as the plain of Sibari . The highest point is the Monte Pollino 2,233 metres (7,325 ft). The chief rivers are

7426-535: The only glacier in the Apennines. The eastern slopes down to the Adriatic Sea are steep, whilst the western slopes form foothills on which most of the towns of peninsular Italy are located. The mountains tend to be named after the province or provinces in which they are located; for example the Ligurian Apennines are in Liguria . The etymology most frequently repeated, because of its semantic appropriateness,

7520-419: The passively retreating oceanic slab had to adjust and deform in relation the large and buoyant continental sectors. Post-Pliocene migration was eventually driven through the narrow corridor (250 km) represented by the present Ionian Sea and thus separated the Adriatic and Sicilian sectors. Changes in lithospheric composition may have also contributed to differences in subduction geometry. For instance, during

7614-526: The presence of a saddle containing continental crust (the "Issel bridge") between the Vavilov and Marsili plains, implies that there were two distinct episodes of back-arc extension. Between the Tortonian and middle Pliocene, W-E directed extension opened the Vavilov plain and Sardinia margin in the northwest portion of the present day basin. By the end of the Pliocene, extension rapidly turned to NW-SE and

7708-541: The sea, occurs on the east coast, extending halfway across the peninsula. Here the limestone Apennines proper cease and the granite mountains of Calabria begin. The first group extends as far as the isthmus formed by the gulfs of South Eufemia and Squillace; it is known as the Sila, and the highest point reached is 1,930 metres (6,330 ft) (the Botte Donato ). The forests which covered it in ancient times supplied

7802-530: The south edge of the basin near the Sicily Channel . Here, the small Narciso and Nilde fields produce sulphur-rich, light to medium-grade crude oil ( API gravity ranging between 21 and 39). The primary reservoirs in these fields are Miocene karstic limestones that are sealed by Pliocene clays . The source of the hydrocarbons is unknown but is inferred to be Mesozoic limestone. Traps are structural in nature and are primarily thrust faults related to

7896-568: The state railway system, highly developed on the coastal plain, now traverses the mountains routinely through a number of railway tunnels, such as the one at Giovi Pass . The southeastern border of the Ligurian Apennines is the Fiume Magra , which projects into the Tyrrhenian Sea south of La Spezia , and the Fiume Taro , which runs in the opposite direction to join the Po. The divide between

7990-458: The syn-rift and post-rift periods is believed to be located in a 50-meter section of late Messinian gypsum that overlays the calcareous ooze and claystone formations. At the top of the stratigraphic section are 243 meters of Pliocene to Pleistocene post-rift sediment containing calcareous mud with occasional terrigenous clastics and volcanic ash . The Lower Sardinia Margin lies near the transition between continental and oceanic crust . This

8084-784: The three parallel chains are broken up into smaller groups; among them may be named the Matese , the highest point of which is the Monte Miletto 2,050 metres (6,725 ft). The chief rivers on the south-west are the Liri or Garigliano with its tributary the Sacco, the Volturno , Sebeto, Sarno, on the north the Trigno, Biferno and Fortore . Daunian mountains , in Apulia , are connected with

8178-794: The two upper river valleys is the Cisa Pass . Under it (in two tunnels) runs the Autostrada della Cisa between Spezia and Parma . Starting at Cisa Pass , the mountain chain turns further to the southeast, to cross the peninsula along the border between the Emilia-Romagna and Tuscany regions. They are named the Tuscan–Emilian Apennines west of the Futa Pass and the Tuscan–Romagnol Apennines east of it, or just

8272-749: The valley of the Aterno to Sulmona. In ancient times the Via Salaria , Via Caecilia and Via Tiburtina all ran from Rome to the Adriatic coast . The volcanic mountains of the province of Rome are separated from the Apennines by the Tiber valley, and the Monti Lepini , part of the Volscian chain, by the valleys of the Sacco and Liri . In the southern Apennines, to the south of the Sangro valley,

8366-469: The valley of the Negro, is planned to extend to Cosenza, along the line followed by the ancient Via Popilia, which beyond Cosenza reached the west coast at Terina and thence followed it to Reggio. The Via Herculia  [ it ] , a branch of the Via Traiana , ran from Aequum Tuticum to the ancient Nerulum . At the narrowest point the plain of Sibari, through which the rivers Coscile and Crati flow to

8460-421: The vesicles, it is likely that the basalt was emplaced as a flow rather than a sill . Overlaying the basement is 250 meters of calcareous mud and ooze with interbedded volcanoclastic layers. Benthic foraminifera and magnetic anomaly data from the base of this section constrain the terminus of rifting between 1.67 and 1.87 Ma. At the top of the stratigraphic section are 350 meters of volcanoclastic turbidites . It

8554-851: The water of which is both drunk on the spot and sold as table water elsewhere. The Apennines are home to twelve Italian national parks : the Appennino Tosco-Emiliano National Park , the Foreste Casentinesi, Monte Falterona, Campigna National Park , the Monti Sibillini National Park , the Gran Sasso e Monti della Laga National Park , the Abruzzo, Lazio and Molise National Park , the Maiella National Park ,

8648-556: The wild goats called rotae , spoken of by Marcus Terentius Varro ( Rerum rusticarum II. i. 5), which may have been either Pyrenean chamois or steinbock , to be found. Brigandage appears to have been prevalent in Roman times in the more remote parts of the Apennines, as it was until recently. An inscription found near the Furlo pass was set up in AD 246 by an evocatus Augusti (a member of

8742-411: Was limited to the southeastern Marsili plain. This rapid shift in the direction and spatial location of extension may be due to how the relative velocities of interacting tectonic plates change over time. For example, if the horizontal velocity of the overriding Eurasian plate exceeds the velocity of slab rollback and trench retreat in the underthrusting African plate, then extension should not occur in

8836-402: Was opened after many years of construction consisting of major tunnels (the longest being the new 8.6-kilometre (5.3-mile) 'Tunel Base') and new overpasses, shortening the traveling time between Florence and Bologna by road. The Foreste Casentinesi, Monte Falterona, Campigna National Park is in the southern part of the Tuscan–Romagnol Apennines. The southern limit of the Tuscan–Romagnol Apennines

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