Geological Map of the Valle Mosso Pluton (Piemonte, Italy)
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433000 435000 437000 439000 441000 550 550 16° 10° 11° 12° 13° 14° 15° 650 500 M. Orfano b) Simplified tectonic outline of the Alps after Pianezza 5° 6° 7° Munich 48° 48° 8° 9° Handy et al. (2005). Pianceri N Riale Carnascio 450 Basel Torrente 500 700 600 Sessera Graz 47° Gila 47° Bern 750 46° 46° 800 Valpiana Zagreb di LINE Croso Milan Venice LINE Adriatic 100 km units PRAY 45° 45° 500 Sea 500 450 Turin Outline of the 15° 16° Azoglio 11° 12° 13° 14° Val Lakes Massif 450 INSUBRIC A' Geological map of the Pennine Helvetic and POGALLO Castagnea 400 44° Austroalpine d'Ossola 550 Ultrahelvetic Domain PORTULA 500 Ligurian Sea Domain Sessera 6° 7° 8° 9° 10° Penninic Domain Southalpine Maggiore and Pre-Alps Domain Val Strona 600 Tertiary plutons 650 LINE Lago Torrente 650 Valle Mosso pluton (Piemonte, Italy) 400 Val Sesia CMB N Lago Galfione 600 Ropolo d'Orta Plain Crosa 450 LINE Po (1) (2) (3) (3) (2) Crosa Tavazzani Lorenzo , Peres Stefano , Sinigoi Silvano , Demarchi Gabriella , Musumeci Giovanni 500 Val TRIVERO della 10 km Ronco 450 del sera LINE Ses 500 AUSTRO-ALPINE DOMAIN Pianaccia 550 Prete (1) Dedman College of Humanities and Sciences, Southern Methodist University, Dallas, US N 550 Flecchia Sesia Zone Mucengo 650 (2) Dipartimento di Scienze della Terra, Università degli studi di Pisa, Italy INSUBRIC SOUTHERN-ALPINE DOMAIN Guala CREMOSINA Permian-Mesozoic volcanic Rio Barbero 450 600 (3) Dipartimento di Matematica e Geoscienze, Università degli studi di Trieste, Italy 5057000 5057000 and sedimentary rocks Coggiolasca Permian granitic rocks 500 (Lake’s granites) Outline of 650 SERIE DEI LAGHI map area 550 500 km IVREA-VERBANO ZONE Mafic Complex Ponzone Units Explanation: Geological sketch map Ronco Valle Fredda 600 a) DEM of the italian peninsula, c) Lakes Massif geological map Kinzigite Formation Canale the Alps profile is outlined. after Zingg (1983). Mantle Peridotite 435074 439074 Vico 550 SURFICIAL DEPOSITS EXPLANATIONS OF MAP SYMBOLS 600 Pratrivero Riale Solesio Torrente 650 Grosso 1250 Alluvium 900 950 Mazza Moialunga Boulders, cobbles, gravel, sand, and silt underlying present flood plains are 45 N 1200 700 Strike and dip of volcanoclastic sediments and eutaxitic 1000 Trabuldo A' Cereie 500 700 Qa mapped as alluvium. Pramorisio foliation in pyroclastic rocks 1050 HOLOCENE Pray 750 45 550 la Colma 600 1100 S.S Terraced deposits Strike and dip of bed in sedimentary rocks Trivero 1150 Bulliana 650 0 1 2 km N. 232 800 Riale Poorly consolidated to unconsolidated materials ranging in grain size from 850 Monte boulders to clay and deposited up to 30 to 40 m above the currently active 45 Mazzucco Qt Cattivo 500 550 Pisciavacche flood plains are mapped as terrace deposits. 600 Strike and dip of foliation and banding in metamorphic rocks Pratrivero PLEISTOCENE - HOLOCENE 700 Capo Mosso 500 550 Sedimentary deposits, undivided 550 45 600 450 Moderately consolidated deposits of conglomerate, sandstone, and shale la Valle Strike and dip of foliation and banding in igneous rocks Sella Ponzone 750 Ponzone Valle Qtu with minor carbonate are mapped as undivided Tertiary to Quaternary 650 Vaudano 5056000 sedimentary deposits. These are distinguished from other surficial deposits 5056000 Fila Rif.o La Sella 45 by greater consolidation and moderate dips of up to 20°. Monte Orbetto Comune Dip of fault planes 650 TERTIARY - QUATERNARY Mosso S. Maria 700 M. Solivo M. Orbetto Baltigati 650 Ponzone 600 550 Crocemosso MOSSO TERTIARY MAGMATISM OF THE WESTERN ALPS Contact: solid where observed, dashed where Soprana Monte Localà 500 S. Bononio 450 approximately located, dotted where concealed Monte Bastia Torrente Dikes related to Alpine orogenic magmatism 550 500 550 B'' 500 Gradational contact : solid where observed, dashed B' Variably porphyritic basalts, basaltic andesites and andesites dikes that A Valle Mosso where approximately located. 600 belongs to the calcalkaline and shoshonitic series, that contains various 5055000 5055000 fAb 600 proportions of hornblende, clinopyroxene, plagioclase phenocrysts and Colma Fault, showing dip where measured. Dashed where 750 M. Capoposto minor biotite. 700 Vivaro Colmo approximately located, dotted where concealed. Cerruti 550 OLIGOCENE 550 500 500 650 600 Monte Rovella Cerruti 550 IGNEOUS ROCKS OF PERMIAN AGE A' Pistolesa Traces of the geological cross sections 550 A Strona 550 Cerreia 450 VOLCANIC ROCKS OF THE SESIA CALDERA 5052000 5052000 600 Ordivaro B Casapinta 450 Monte Localà Rhyolitic rocks Piane 500 Orange to red-weathering volcanic and hypabissal rhyolite porphyry that delle SOPRANA contains small (0.5-3 millimetre (mm)) crystals of quartz and feldspar Lago 450 Crocemosso 650 r 550 550 Orzera dispersed in a pink aphanitic matrix. Includes ignimbrite with abundant 500 Valle San Nicolao fiamme and eutaxitic textures, volcanic breccia and massive porphyry. 550 500 600 Andesitic lava flows are also reported to form decametric-scale concordant 500 Lanvario 500 bodies within the main rhyolitic body. VEGLIO 500 600 450 S. Bononio PERMIAN 500 Calvino 550 500 500 VALLE MOSSO DIKES SYSTEM M. Bastia 550 Ronco Masserano 650 Quartz dikes Drift and solid map Mad.na del Sabbione 450 Hydrothermal origin, mainly quartz-made dikes. Lessona Orcurto 500 B'' Due to the poor exposure of bedrock in the surveyed area, the inferred 450 450 fq PERMIAN lithostratigraphic configuration has been represented on a ‘drift and solid’ 600 435074 439074 B' 600 400 map, in which surfacing rocks are separated by drift cover. 431074 550 A 400 Vergnago The distinction between outcropping and covered bedrock has been Doleritic and dioritic dikes A' highlighted on the map with a different intensity of the colours indicating Units explanation Valle Mosso pluton Traces of the geological Mafic-dikes ranging from basaltic to dioritic in composition. They present the geological units. A 500 cross sections disrupted margin usually associated with swarms of fine-grained enclaves Montaldo 550 fb Surficial deposits Equigranular pink monzogranite of hybrid dioritic magma into the granitic host-rock. Contacts between 550 VALLE MOSSO Premarcia 500 Equigranular white monzogranite intrusive units 500 PERMIAN Rhyolitic rocks Sub-outcropping bedrock Contacts between ROSSE 450 Porphyritic monzogranite 450 geological units Strona Piana Foglio Mino Mafic plutonic rocks 500 450 Microgranitic porphiry Contacts between S. Rocco VALLE MOSSO INTRUSIVE BODY 550 400 bedrock and cover 5053000 S. Martino 5053000 Undivided paragneiss Two-mica leucogranite Strike-slip fault Role Equigranular pink leucomonzogranite Outcropping bedrock Undivided orthogneiss 700 (certain, inferred) S. Nicolao 400 Granodioritic monzogranite 500 400 400 400 Equigranular medium-grained leucogranites, usually bright pink, with 550 600 RIVE vgrU isotropic textures composed of mm-sized K-feldspar, quartz, biotite and 450 rare plagioclase crystals. Granophyric texture domains are locally abundant. Rare cm-sized miarolitic cavities and pegmatitic pockets are 650 Cedreie 400 Falcero 450 also present. 450 400 Upper Valle Mosso Facies Valle Piana Fangazio LE Bioletto M. Rovella Bugelio PERMIAN 500 Granitic facies and conceptual model Mondalforno Equigranular white monzogranite 850 400 350 Equigranular medium- to coarse-grained monzogranites that show an isotropic texture composed of cm-sized K-feldspar, plagioclase and quartz 450 400 350 Torrente Bric Montuoso vgrE crystals with ≈ 5% biotite occurrence. A B 0 km 800 Zoppo 400 Montaldo Facies 400 Campore dello 350 PERMIAN Cigliaga Rio 750 Strona 350 Rio 450 Fontanella-Ozino 450 400 Microgranitic porphyry Torrente 350 Markedly porphyric granitoid rocks composed of cm-sized K-feldspar, 700 350 2 km 400 Bisignana plagioclase and quartz crystals in a quasi-aphanitic biotite-rich matrix. 400 vgrM 650 Countless small biotite–rich enclaves, rapakivi and anti-rapakivi reaction Cagne 400 Caudana rims and resorbed quartz crystals are peculiar features of this granitic facies. Gabella Bric Mazzero Monte Bastia Facies Alcinengo della PERMIAN 4 km 600 CASAPINTA Markedly inequigranular to porphyritic monzogranite 1 cm 1 cm STRONA Riale 400 350 Medium-grained monzogranites, inequigranular for euedral cm-sized (2- 4 Mornengo 450 350 Bosi cm) K-feldspar crystals, plagioclase, quartz and ≈ 10% biotite. Locally vgrP abundant mafic microgranular enclaves. 6 km B 350 C D 300 Vaudano Facies Aimone PERMIAN Ferrere 350 Piane 400 Two-mica leucogranite 5051000 400 5051000 Fine-grained muscovite-rich leucogranites. Equigranular rocks that show 8 km 550 Gianadda Colongo an isotropic texture made up of K-feldspar, plagioclase, quartz, muscovite 500 delle vgrF Quario 350 and variable amount of biotite. Occurrence of xenocrystc andalusite is also Lago reported from several outcrops. Franzoi Fila Facies Crosa Torrente Ostola 300 10 km S.S PERMIAN VALLE 350 N. 232 Granodioritic monzogranite Cacciano 1 cm 1 cm Medium to coarse grained monzogranitic granodiorite. Equigranular to S. NICOLAO 450 300 mildly inequigranular due to the presence of K-feldspar crystals with size Colle Rufino 400 400 vgrL Campalveno S.Liberata ranging from 0,5 to 2 cm, abundant plagioclase, quartz, around 15% biotite 12 km and rare amphibole. It shows faint magmatic foliation and growth of garnets E F 350 Cremosina Line 450 350 350 300 near to the contact with its metamorphic host rocks. Locally abundant mafic BIOGLIO 400 microgranular enclaves. 400 Lower Valle Mosso Facies 400 14 km 350 Rongio PERMIAN 300 Forte 350 Maglione 350 Bozzone INTRUSIVE ROCKS OF THE MAFIC COMPLEX, IVREA-VERBANO ZONE 0