Hercynian Metamorphism in the Catalonian Coastal Ranges
... After the second phase of Hercynian deformation, igneous rocks were intruded in the Catalonian Coastal Ranges, producing contact metamorphism in the country rocks. Most of these igneous rocks are granitoids which reach shallow crustal levels and were intruded after the development of crenulation cle ...
... After the second phase of Hercynian deformation, igneous rocks were intruded in the Catalonian Coastal Ranges, producing contact metamorphism in the country rocks. Most of these igneous rocks are granitoids which reach shallow crustal levels and were intruded after the development of crenulation cle ...
Subduction and eduction of continental crust: major mechanisms
... stabilize coesite (Mirwald and Massonne, 1980), which is consistent with the estimated equilibration pressure for Proterozoic, Alpine-type peridotite bodies that occur scattered throughout a large portion of the WGR (Jamtveit et al., 1991). The Proterozoic assemblages in these mantle fragments have ...
... stabilize coesite (Mirwald and Massonne, 1980), which is consistent with the estimated equilibration pressure for Proterozoic, Alpine-type peridotite bodies that occur scattered throughout a large portion of the WGR (Jamtveit et al., 1991). The Proterozoic assemblages in these mantle fragments have ...
Labreport HHohmeister
... The German Alps belong to the Northern limestone Alps. Their rocks were sedimented in marine environments further south than their current position. Due to a collision of plates, the layers were intensively convoluted, and limestone was transported to its current location. The northern limestone Alp ...
... The German Alps belong to the Northern limestone Alps. Their rocks were sedimented in marine environments further south than their current position. Due to a collision of plates, the layers were intensively convoluted, and limestone was transported to its current location. The northern limestone Alp ...
Open-file Report 579: Block diagrams and cross sections illustrating
... area, depositing marine and coastal-plain sediments, off and on, over at least 10 million years (part of the rock record is locally eroded away). Marine invertebrate fossils (~96-86 million years old) are abundant in Cretaceous rocks preserved on Sevilleta NWR. Subsidence of the “Western Interior Se ...
... area, depositing marine and coastal-plain sediments, off and on, over at least 10 million years (part of the rock record is locally eroded away). Marine invertebrate fossils (~96-86 million years old) are abundant in Cretaceous rocks preserved on Sevilleta NWR. Subsidence of the “Western Interior Se ...
Document
... BABI - Basaltic Achondrite Best Initial = Bulk Earth, undifferentiated Rb-Sr isochron From meteorites ...
... BABI - Basaltic Achondrite Best Initial = Bulk Earth, undifferentiated Rb-Sr isochron From meteorites ...
Rocks
... and heavy, dark colored and rich in iron and magnesium (these are common in the Hawaiian Islands) Granitic rocks: they are light colored, have lower density than basaltic rocks and they contain a lot of silicon and oxygen Andesitic rocks: they have mineral combinations between granitic and basaltic ...
... and heavy, dark colored and rich in iron and magnesium (these are common in the Hawaiian Islands) Granitic rocks: they are light colored, have lower density than basaltic rocks and they contain a lot of silicon and oxygen Andesitic rocks: they have mineral combinations between granitic and basaltic ...
Who™s On First - Minneota Public Schools
... Lava flows may cause contact-metamorphism with the older rocks they lie upon. ...
... Lava flows may cause contact-metamorphism with the older rocks they lie upon. ...
RelativeActivity
... Lava flows may cause contact-metamorphism with the older rocks they lie upon. ...
... Lava flows may cause contact-metamorphism with the older rocks they lie upon. ...
the granulite belt of lapland and the belomorides
... HAMEURT, J., 1984: Petrogenesis and evolution of an early Proterozoic collisional orogenic belt: The granulite belt of Lapland and the Belomorides (Fennoscandia). Bull. Geol. Soc. Finland 56, Part 1—2, 161—188. The tectonic and metamorphic pattern of the Precambrian crust exposed in the eastern Balt ...
... HAMEURT, J., 1984: Petrogenesis and evolution of an early Proterozoic collisional orogenic belt: The granulite belt of Lapland and the Belomorides (Fennoscandia). Bull. Geol. Soc. Finland 56, Part 1—2, 161—188. The tectonic and metamorphic pattern of the Precambrian crust exposed in the eastern Balt ...
Intrusive and Extrusive Igneous Rocks
... chance to grow. Intrusive igneous rocks have relatively large crystals that are easy to see. Intrusive igneous rocks are also called plutonic. A pluton is an igneous rock body that forms within the crust. Granite is the most common intrusive igneous rock. Pictured below are four types of intrusive r ...
... chance to grow. Intrusive igneous rocks have relatively large crystals that are easy to see. Intrusive igneous rocks are also called plutonic. A pluton is an igneous rock body that forms within the crust. Granite is the most common intrusive igneous rock. Pictured below are four types of intrusive r ...
Plate Tectonics: GL209 Prof. John Tarney Lecture 3: Wilson Cycle 1
... rifts might develop into an ocean (’RRR’), it is more likely that two of these rifts would develop into an ocean (’RRr’), leaving the third rift as a ’failed arm’. They demonstrated / speculated that on many continents it was possible to recognise these RRr junctions. The ’failed arm’ rift would eve ...
... rifts might develop into an ocean (’RRR’), it is more likely that two of these rifts would develop into an ocean (’RRr’), leaving the third rift as a ’failed arm’. They demonstrated / speculated that on many continents it was possible to recognise these RRr junctions. The ’failed arm’ rift would eve ...
Lab: Exploring Patterns in Regional Seismicity
... New ocean crust is created at divergent boundaries, where plates are pulling apart. In these regions, mantle material penetrates through the thinning crust and solidifies. Divergent boundaries can form either in oceanic or continental crust. As the plates pull apart, dense oceanic crust is formed. I ...
... New ocean crust is created at divergent boundaries, where plates are pulling apart. In these regions, mantle material penetrates through the thinning crust and solidifies. Divergent boundaries can form either in oceanic or continental crust. As the plates pull apart, dense oceanic crust is formed. I ...
Rock Reading
... Common igneous rocks are basalt, gabbro, andesite and granite. Igneous rocks formed from magma are called intrusive rocks, whereas those formed from lava are called extrusive rocks. The sizes of mineral crystals that form in igneous rocks indicate the rate at which the magma or lava cooled. Lava coo ...
... Common igneous rocks are basalt, gabbro, andesite and granite. Igneous rocks formed from magma are called intrusive rocks, whereas those formed from lava are called extrusive rocks. The sizes of mineral crystals that form in igneous rocks indicate the rate at which the magma or lava cooled. Lava coo ...
Igneous Rocks and the Rock Cycle
... Pegmatites form late in the crystallization process when there are a lot of fluids present in the molten rock. The fluids enable individual ions to move around more freely, ultimately bonding to form very large and sometimes exotic crystals. Pegmatitic dikes form around the margins of intrusive plut ...
... Pegmatites form late in the crystallization process when there are a lot of fluids present in the molten rock. The fluids enable individual ions to move around more freely, ultimately bonding to form very large and sometimes exotic crystals. Pegmatitic dikes form around the margins of intrusive plut ...
Collision tectonics of the Mediterranean region
... TABLE 1. MAIN COLLISION ZONES IN THE MEDITERRANEAN REGION AND THEIR TECTONIC AND GEODYNAMIC FEATURES ...
... TABLE 1. MAIN COLLISION ZONES IN THE MEDITERRANEAN REGION AND THEIR TECTONIC AND GEODYNAMIC FEATURES ...
The evolution of continental crust
... the mantle of a geologically active planet. Like a form of continuous distillation, volcanism can then lead to the production of highly diÝerentiated magma of a composition that is distinct from basaltÑcloser to that of the light-colored igneous rock granite. Because the recycling necessary to gener ...
... the mantle of a geologically active planet. Like a form of continuous distillation, volcanism can then lead to the production of highly diÝerentiated magma of a composition that is distinct from basaltÑcloser to that of the light-colored igneous rock granite. Because the recycling necessary to gener ...
R7: Taylor-Evolution of Continental Crust
... the mantle of a geologically active planet. Like a form of continuous distillation, volcanism can then lead to the production of highly diÝerentiated magma of a composition that is distinct from basaltÑcloser to that of the light-colored igneous rock granite. Because the recycling necessary to gener ...
... the mantle of a geologically active planet. Like a form of continuous distillation, volcanism can then lead to the production of highly diÝerentiated magma of a composition that is distinct from basaltÑcloser to that of the light-colored igneous rock granite. Because the recycling necessary to gener ...
Metamorphic Rocks and the Creation of Gemstones
... new rock called a metamorphic rock. Metamorphic rocks are not melted as they form (that would be igneous), and change takes place in a solid state. Heat and pressure are forms of energy and when any preexisting rock is heated fluids already within the rock may also be involved in changing the rock. ...
... new rock called a metamorphic rock. Metamorphic rocks are not melted as they form (that would be igneous), and change takes place in a solid state. Heat and pressure are forms of energy and when any preexisting rock is heated fluids already within the rock may also be involved in changing the rock. ...
No. 51. The Sveconorwegian Orogen of southern Scandinavia
... Fennoscandia (the southwestern continental segment of Baltica) and another continent in late Mesoproterozoic time. The orogenic province is composed of five distinct Proterozoic gneiss segments that were displaced and reworked during a succession of compressional (and extensional) orogenic phases at ...
... Fennoscandia (the southwestern continental segment of Baltica) and another continent in late Mesoproterozoic time. The orogenic province is composed of five distinct Proterozoic gneiss segments that were displaced and reworked during a succession of compressional (and extensional) orogenic phases at ...
Introduction to the special volume “Subduction
... – Rogers 2003). The age of metamorphism remains a matter of discussion in some areas. Crystalline basement is covered by Late Cretaceous to Paleogene continental sediments (the Totogalpa Formation in Nicaragua) and basic volcanites (in the neighboring Honduras). Occurrences of metabasic rocks to the ...
... – Rogers 2003). The age of metamorphism remains a matter of discussion in some areas. Crystalline basement is covered by Late Cretaceous to Paleogene continental sediments (the Totogalpa Formation in Nicaragua) and basic volcanites (in the neighboring Honduras). Occurrences of metabasic rocks to the ...
Volcano-tectonic Earthquakes during the Stage of Magma
... the inflation of the Aira caldera progressed since +33-. In particular, VT earthquakes SW o# the volcano and in the caldera swarmed during November ,**-ῌFebruary ,**., and then a baseline of GPS across the volcano indicated a significant extension. However, no significant increase in eruptive activity ...
... the inflation of the Aira caldera progressed since +33-. In particular, VT earthquakes SW o# the volcano and in the caldera swarmed during November ,**-ῌFebruary ,**., and then a baseline of GPS across the volcano indicated a significant extension. However, no significant increase in eruptive activity ...
Chapter 3 - Igneous Rocks
... Silica rich (felsic) magma/lavas are thick, viscous and resist flow Silica poor (mafic) magma/lavas are thinner, have a lower viscosity and don’t ...
... Silica rich (felsic) magma/lavas are thick, viscous and resist flow Silica poor (mafic) magma/lavas are thinner, have a lower viscosity and don’t ...
Divergent Boundaries - Phil Farquharson`s Geo
... Subducting plates: The demise of an ocean basin The Farallon plate once occupied much of the eastern Pacific basin zBeginning 180 million years ago the Farallon plate was subducting beneath the Americas faster than it was being generated zThe plate got continually smaller and now only fragments of t ...
... Subducting plates: The demise of an ocean basin The Farallon plate once occupied much of the eastern Pacific basin zBeginning 180 million years ago the Farallon plate was subducting beneath the Americas faster than it was being generated zThe plate got continually smaller and now only fragments of t ...
Chapter 2
... Traces or remains of prehistoric life Are the most important inclusions Help determine past environments Used as time indicators Used for matching rocks from different places ...
... Traces or remains of prehistoric life Are the most important inclusions Help determine past environments Used as time indicators Used for matching rocks from different places ...
MOUNTAINS - cravenccgeology
... Although folding is often the most obvious sign of these forces, thrust faulting, metamorphism, and igneous activity are always present in varying degrees. Most mountain building occurs at convergent plate boundaries, which can involve both oceanic and continental crust. Mountain building occurs at ...
... Although folding is often the most obvious sign of these forces, thrust faulting, metamorphism, and igneous activity are always present in varying degrees. Most mountain building occurs at convergent plate boundaries, which can involve both oceanic and continental crust. Mountain building occurs at ...
Great Lakes tectonic zone
The Great Lakes tectonic zone is bounded by South Dakota at its tip and heads northeast to south of Duluth, Minnesota, then heads east through northern Wisconsin, Marquette, Michigan, and then trends more northeasterly to skim the northern-most shores of lakes Michigan and Huron before ending in the Sudbury, Ontario, Canada, area.During the Late Archean Era the Algoman orogeny added landmass to the Superior province by volcanic activity and continental collision along a boundary that stretches from present-day South Dakota, U.S., into the Lake Huron region near Sudbury, Ontario, Canada.This crustal boundary is the Great Lakes tectonic zone. It is 1,400 km (870 mi) long, and separates the older Archean gneissic terrane to the south from younger Late Archean greenstone-granite terrane to the north.The zone is characterized by active compression during the Algoman orogeny (about 2,700 million years ago), a pulling-apart (extensional) tectonics (2,450 to 2,100 million years ago), a second compression during the Penokean orogeny (1,900 to 1,850 million years ago), a second extension during Middle Proterozoic time (1,600 million years ago) and minor reactivation during Phanerozoic time (the past 500 million years).Collision began along the Great Lakes tectonic zone (GLTZ) with the Algoman mountain-building event and continued for tens of millions of years. During the formation of the GLTZ, the gneissic Minnesota River Valley subprovince was thrust up onto the Superior province's edge as it consumed the Superior province's oceanic crust. Fragmentation of the Kenorland supercontinent began 2,450 million years ago and was completed by 2,100 million years ago. The Wyoming province is the continental landmass that is hypothesized to have rifted away from the southern Superior province portion of Kenorland, before moving rapidly west and docking with the Laurentia supercontinent 1,850 to 1,715 million years ago. Sedimentation from the GLTZ-rifting environment continued into the Penokean orogeny, which is the next major tectonic event in the Great Lakes region. Several earthquakes have been documented in Minnesota, Michigan's Upper Peninsula and Sudbury in the last 120 years along the GLTZ.