as a PDF
... The primary evidence for Tertiary extension between East and West Antarctica is found in the Adare Trough, located 100 km northeast of Cape Adare. It represents the extinct third arm of a Tertiary spreading ridge system near a triple junction that separated East and West Antarctica between 43 Ma and ...
... The primary evidence for Tertiary extension between East and West Antarctica is found in the Adare Trough, located 100 km northeast of Cape Adare. It represents the extinct third arm of a Tertiary spreading ridge system near a triple junction that separated East and West Antarctica between 43 Ma and ...
4.19 MB - GODAC Data Site -NUUNKUI
... known as independent component analysis reveals that the mantle composition differs in the eastern and western hemispheres. It is further possible to trace the development of this east-west structure back several hundred million to a billion years by using isotopic ratios. We hypothesize that the ea ...
... known as independent component analysis reveals that the mantle composition differs in the eastern and western hemispheres. It is further possible to trace the development of this east-west structure back several hundred million to a billion years by using isotopic ratios. We hypothesize that the ea ...
Lecture 6 - Mantle and Basalts
... The crust is 5 -10 km thick. We know what the crust looks like from its pieces that were obducted onto the continents. Such pieces of the crust are called ophiolites The ocean crust consist of a) b) c) d) e) ...
... The crust is 5 -10 km thick. We know what the crust looks like from its pieces that were obducted onto the continents. Such pieces of the crust are called ophiolites The ocean crust consist of a) b) c) d) e) ...
Supercontinent cycles and the distribution of metal
... orogenic activity during the aggregation of cratons to form a large continent (2.0 to 1.8 Ga). Sediment-hosted Cu mineralization occurred at Udokan (in Siberia) within this postulated continent at ~2.0 Ga (Fig. 1C). However, orogeny and related mineralization occurred along a continental margin that ...
... orogenic activity during the aggregation of cratons to form a large continent (2.0 to 1.8 Ga). Sediment-hosted Cu mineralization occurred at Udokan (in Siberia) within this postulated continent at ~2.0 Ga (Fig. 1C). However, orogeny and related mineralization occurred along a continental margin that ...
deep sea drilling in the northern indian ocean
... evolutionary history of the Indian Ocean (Figure 2), which formed as a result of fragmentation and dispersal of a super continent named Pangea. At about 200 Ma the Pangean super continent began to split into Laurasia (northern part) and Gondwanaland (southern part). The main Gondwanaland, which cons ...
... evolutionary history of the Indian Ocean (Figure 2), which formed as a result of fragmentation and dispersal of a super continent named Pangea. At about 200 Ma the Pangean super continent began to split into Laurasia (northern part) and Gondwanaland (southern part). The main Gondwanaland, which cons ...
1.6 General age and tectonic setting of the Arabian Shield
... The geologic history of the Arabian Shield covers a broad sweep of geologic time from distant beginnings more than 2,000 million years ago to present day processes that are sculpting and changing the rocks and landscape of the shield. The core of the history covers a 300-million-year period between ...
... The geologic history of the Arabian Shield covers a broad sweep of geologic time from distant beginnings more than 2,000 million years ago to present day processes that are sculpting and changing the rocks and landscape of the shield. The core of the history covers a 300-million-year period between ...
The Agulhas – Karoo Geoscience Transect: from a sheared margin
... can be extinct island arcs, extinct spreading ridges, seamounts, or disrupted fragments of continental crust, are passive features that are embedded within the oceanic lithosphere. When large enough, they resist subduction, do not return to the mantle but accrete to existing continents. A prime exam ...
... can be extinct island arcs, extinct spreading ridges, seamounts, or disrupted fragments of continental crust, are passive features that are embedded within the oceanic lithosphere. When large enough, they resist subduction, do not return to the mantle but accrete to existing continents. A prime exam ...
Edmond and Huh 2003 - Department of the Geophysical Sciences
... perturbations in this balance bring about changes in PCO2 , but given the small size of the atmospheric CO2 reservoir relative to the rate of fixation by weathering, mechanisms that maintain this apparently precarious balance dominate current thinking. At present, the Atlantic and Indian oceans are ...
... perturbations in this balance bring about changes in PCO2 , but given the small size of the atmospheric CO2 reservoir relative to the rate of fixation by weathering, mechanisms that maintain this apparently precarious balance dominate current thinking. At present, the Atlantic and Indian oceans are ...
Chapter 10 Worksheet
... On the front of the terrain below, sketch your interpretation of the geometry of plates at depth, such as a subduction zone or midocean ridge. Draw arrows to indicate which way the plates are moving relative to each other and show where melting is occurring at depth to form volcanoes on the surface. ...
... On the front of the terrain below, sketch your interpretation of the geometry of plates at depth, such as a subduction zone or midocean ridge. Draw arrows to indicate which way the plates are moving relative to each other and show where melting is occurring at depth to form volcanoes on the surface. ...
THE ORIGIN AND GROWTH OF CONTINENTS 1 Geophysical
... periods; (3) the continents have grown throughout geological time and are now more extensive than previously; (4) talc-alkaline volcanic rocks, in particular andesites, are characteristic of erogenic areas. Geochemical evidence shows that: (1) the continental crust has an overall composition (for ma ...
... periods; (3) the continents have grown throughout geological time and are now more extensive than previously; (4) talc-alkaline volcanic rocks, in particular andesites, are characteristic of erogenic areas. Geochemical evidence shows that: (1) the continental crust has an overall composition (for ma ...
Not Getting the Drift - Personal webpages at NTNU
... The progress of geologic understanding over the past two centuries is well documented in beautifully written and illustrated textbooks. Sir Charles Lyell (17971875) was the most productive and influential of the early textbook authors. His main income came from his books. He began his career with a ...
... The progress of geologic understanding over the past two centuries is well documented in beautifully written and illustrated textbooks. Sir Charles Lyell (17971875) was the most productive and influential of the early textbook authors. His main income came from his books. He began his career with a ...
Forum Reply - Francis A. Macdonald
... to Gondwana the 613 ± 3 Ma gneisses of the Pelham dome, and use this as an argument to better delineate the Red Indian Line. However, Tucker and Robinson (1990) state that distinguishing between a Gondwanan and Laurentian affinity for these rocks is not possible based simply on the presence of Neopr ...
... to Gondwana the 613 ± 3 Ma gneisses of the Pelham dome, and use this as an argument to better delineate the Red Indian Line. However, Tucker and Robinson (1990) state that distinguishing between a Gondwanan and Laurentian affinity for these rocks is not possible based simply on the presence of Neopr ...
Wanke et al_Karoo unconformities
... the Huab area could be younger than the Etjo Formation in its Mount Etjo-Waterberg type area farther east. This conforms with recent 40Ar/39Ar dates of 132±1 Ma for basalts interfingering with the top part of the underlying fluvio-aeolian succession (Renne, written comm. 1997) and 40Ar/39Ar dates of ...
... the Huab area could be younger than the Etjo Formation in its Mount Etjo-Waterberg type area farther east. This conforms with recent 40Ar/39Ar dates of 132±1 Ma for basalts interfingering with the top part of the underlying fluvio-aeolian succession (Renne, written comm. 1997) and 40Ar/39Ar dates of ...
Plate Tectonics Teacher Assessment User Manual
... C1 All of Earth’s plates move very slowly (a few centimeters per year). C1.1 Since the continents are a part of the plates, they move in the exact same way as the plate moves. C2 A plate’s size and/or shape can be changed over time. C2.1 An individual plate (and its continent if present) may split a ...
... C1 All of Earth’s plates move very slowly (a few centimeters per year). C1.1 Since the continents are a part of the plates, they move in the exact same way as the plate moves. C2 A plate’s size and/or shape can be changed over time. C2.1 An individual plate (and its continent if present) may split a ...
The Floor of the Arctic Ocean in Photographs
... spots cannot be attributed to poor photographic technique and must represent highly reflectivematerial either in the water or on the bottom. If they were due to suspended matter they would be distributed relatively uniformly throughout the field, yet theyare more concentrated around the ice-rafted r ...
... spots cannot be attributed to poor photographic technique and must represent highly reflectivematerial either in the water or on the bottom. If they were due to suspended matter they would be distributed relatively uniformly throughout the field, yet theyare more concentrated around the ice-rafted r ...
Marked Manuscript_GR_RK
... rifting and drifting. According to Storey et al. (1995) the Marion hotspot initiated the breakup of ...
... rifting and drifting. According to Storey et al. (1995) the Marion hotspot initiated the breakup of ...
Linking rift propagation barriers to excess magmatism at volcanic
... the Florianópolis fracture zone (FZ), Brazil (Fig. 1), initiated at ca. 112 Ma (e.g., Torsvik et al., 2009; Moulin et al., 2010; Heine et al., 2013), resulting in an interval of ~20 m.y. between break-up ages of southern (134 Ma) and northern (112 Ma) segments (Franke, 2013). The ParanáEtendeka LIP ...
... the Florianópolis fracture zone (FZ), Brazil (Fig. 1), initiated at ca. 112 Ma (e.g., Torsvik et al., 2009; Moulin et al., 2010; Heine et al., 2013), resulting in an interval of ~20 m.y. between break-up ages of southern (134 Ma) and northern (112 Ma) segments (Franke, 2013). The ParanáEtendeka LIP ...
GEO100 05 plate tectonics
... The lithosphere is divided into plates that move relative to one another, and relative to the earth’s asthenosphere. Movement occurs at very slow (cm/yr) rates. As a plate moves, its interior remains relatively intact (but it is not totally ridged) while its boundaries become deformed. ...
... The lithosphere is divided into plates that move relative to one another, and relative to the earth’s asthenosphere. Movement occurs at very slow (cm/yr) rates. As a plate moves, its interior remains relatively intact (but it is not totally ridged) while its boundaries become deformed. ...
R7: Taylor-Evolution of Continental Crust
... thought to originate deep in this subcrustal region. Measurements show that diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins di ...
... thought to originate deep in this subcrustal region. Measurements show that diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins di ...
The evolution of continental crust
... thought to originate deep in this subcrustal region. Measurements show that diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins di ...
... thought to originate deep in this subcrustal region. Measurements show that diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins di ...
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... years. South of it the convergence rate at the margin has decreased frwn 5.5 cmlyrat ninemy. to3.6 cmlyr (perpendicular subduction of 3.2 cmlyr) in the past one million years, a result which is Similar to that of Chase etal. (1975). However, to the north of it (the Explorer plate) convergence at the ...
... years. South of it the convergence rate at the margin has decreased frwn 5.5 cmlyrat ninemy. to3.6 cmlyr (perpendicular subduction of 3.2 cmlyr) in the past one million years, a result which is Similar to that of Chase etal. (1975). However, to the north of it (the Explorer plate) convergence at the ...
Global mass wasting during the Middle Ordovician: Meteoritic trigger
... of almost 10 Ma. Having strong arguments against the impact-related hypothesis, we propose an alternative explanation, which is based on a re-evaluation of the mass wasting sites, considering their plate-tectonic distribution and the global sea level curve. A striking and important feature is the di ...
... of almost 10 Ma. Having strong arguments against the impact-related hypothesis, we propose an alternative explanation, which is based on a re-evaluation of the mass wasting sites, considering their plate-tectonic distribution and the global sea level curve. A striking and important feature is the di ...
Southwest U.S. Region Mountain
... Its subduction built most of the North American Cordillera, bunching up the west end of the North American plate like folds It is also the origin of the Sierra Nevada Batholith via subduction under North America ...
... Its subduction built most of the North American Cordillera, bunching up the west end of the North American plate like folds It is also the origin of the Sierra Nevada Batholith via subduction under North America ...
A R T I C L E S - Geoscience Research Institute
... present rate of transport of sediment by rivers could fill the oceans 19× in 3500 Ma. Of course, the oceans, which average 3.8 km in depth of water, are not at all full of sediment; and in much of the deep oceanic abyssal plains, sediment thickness averages only a few hundred meters. It would take a ...
... present rate of transport of sediment by rivers could fill the oceans 19× in 3500 Ma. Of course, the oceans, which average 3.8 km in depth of water, are not at all full of sediment; and in much of the deep oceanic abyssal plains, sediment thickness averages only a few hundred meters. It would take a ...
Pangaea
Pangaea or Pangea (/pænˈdʒiːə/) was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It assembled from earlier continental units approximately 300 million years ago, and it began to break apart about 175 million years ago. In contrast to the present Earth and its distribution of continental mass, much of Pangaea was in the southern hemisphere and surrounded by a super ocean, Panthalassa. Pangaea was the last supercontinent to have existed and the first to be reconstructed by geologists.