Computer exercises in tectonics
... that the North American continent has grown with time. Episodes of mountain building (tectonism or orogeny) and volcanism are often related to the collision or break-up of continents. One part of this process is shown in Figure 2. Figure 2A shows a cross-section of a passive continental margin, simi ...
... that the North American continent has grown with time. Episodes of mountain building (tectonism or orogeny) and volcanism are often related to the collision or break-up of continents. One part of this process is shown in Figure 2. Figure 2A shows a cross-section of a passive continental margin, simi ...
Offshore Somalia: crustal structure and implications
... deforming the post-rift section As there is a marked difference in crustal architecture between the Obbia (north) and Juba-Lamu (south) Basins, it is unsurprising that the subsequent fabric of the post-rift/ drift sections in these basins is also highly variable. Different transitional zones have be ...
... deforming the post-rift section As there is a marked difference in crustal architecture between the Obbia (north) and Juba-Lamu (south) Basins, it is unsurprising that the subsequent fabric of the post-rift/ drift sections in these basins is also highly variable. Different transitional zones have be ...
Anomalous Occurrence of Cretaceous Placer Deposits: A
... deep weathering at that time. Economically important minerals were reworked from their primary sources during these Cretaceous weathering events. The extreme global warmth witnessed in the Cretaceous also caused the melting of most of the polar ice caps, resulting in the expansion of the volume of C ...
... deep weathering at that time. Economically important minerals were reworked from their primary sources during these Cretaceous weathering events. The extreme global warmth witnessed in the Cretaceous also caused the melting of most of the polar ice caps, resulting in the expansion of the volume of C ...
Preliminary fission-track ages of fluorite mineralisation along fracture
... reactivated several times. Fluorite occurs as a Nt number of spontaneous fission tracks matrix mineral in a 5 m-wide breccia zone where Ni number of induced fission tracks the fragments consist of red, hydrothermally N, number of tracks counted in standard altered rock. The induced and standard fiss ...
... reactivated several times. Fluorite occurs as a Nt number of spontaneous fission tracks matrix mineral in a 5 m-wide breccia zone where Ni number of induced fission tracks the fragments consist of red, hydrothermally N, number of tracks counted in standard altered rock. The induced and standard fiss ...
Copyright © 2004, The Geological Society of America, Inc
... During Mesozoic time, the Cordillera of western North America had many orogenies that resulted in a complex and poorly understood mountain belt. The main process for continental growth was terrane accretion, which is the addition of fragments from the oceans (volcanic island arcs, ocean plateaux, oc ...
... During Mesozoic time, the Cordillera of western North America had many orogenies that resulted in a complex and poorly understood mountain belt. The main process for continental growth was terrane accretion, which is the addition of fragments from the oceans (volcanic island arcs, ocean plateaux, oc ...
Wanke et al_Karoo unconformities
... roo Supergroup were indicated by Porada et al. (1996) and Miller (1997) and the most obvious gap between Permian and Cretaceous strata in the Huab area has been used by Milner et al. (1994) as a basis for stratigraphic separation of the Carboniferous-Jurassic Karoo Supergroup from the Cretaceous Ete ...
... roo Supergroup were indicated by Porada et al. (1996) and Miller (1997) and the most obvious gap between Permian and Cretaceous strata in the Huab area has been used by Milner et al. (1994) as a basis for stratigraphic separation of the Carboniferous-Jurassic Karoo Supergroup from the Cretaceous Ete ...
`Gastroliths` deposited by mass flow
... were composed of lithified, fossilbearing sedimentary rock which appeared to be derived from ...
... were composed of lithified, fossilbearing sedimentary rock which appeared to be derived from ...
DNR San Juan Islands Brandon
... 1987), indicating Permian or Triassic metamorphism. Thus, metamorphism of the Vedder coincided with volcanism and chert deposition in the Chilliwack and Deadman Bay terranes. The Vedder may be related to other Permian and Triassic metamorphic units in the western Cordillera, such as the Pinchi Lake ...
... 1987), indicating Permian or Triassic metamorphism. Thus, metamorphism of the Vedder coincided with volcanism and chert deposition in the Chilliwack and Deadman Bay terranes. The Vedder may be related to other Permian and Triassic metamorphic units in the western Cordillera, such as the Pinchi Lake ...
Geology Field Notes: Big Bend National Park, Texas Big Bend is a
... For almost 10 million years after uplift ended, non-marine sediments of the Tertiary period constitute the only record of events in the Big Bend. Dinosaurs had long been gone from the land, their places taken by a proliferation of mammals, many of whose remains have been found in Big Bend ... horses ...
... For almost 10 million years after uplift ended, non-marine sediments of the Tertiary period constitute the only record of events in the Big Bend. Dinosaurs had long been gone from the land, their places taken by a proliferation of mammals, many of whose remains have been found in Big Bend ... horses ...
hallett cove - Palaeo Down Under 2
... About 280 million years ago Australia formed part of a huge single continent called Gondwana, which also included Antarctica, Africa, India and South America. This land mass was centred over the South Pole and was covered by an ice sheet similar to present day Antarctica. This ice sheet moved over s ...
... About 280 million years ago Australia formed part of a huge single continent called Gondwana, which also included Antarctica, Africa, India and South America. This land mass was centred over the South Pole and was covered by an ice sheet similar to present day Antarctica. This ice sheet moved over s ...
Latest Cretaceous basin formation within the Salinian terrane of
... granular massive turbidites and conglomerate beds that have a lenticular geometry, which are most likely the slope-channel fill deposits. Junipero Serra Peak West of Junipero Serra Peak there is a poorly exposed outcrop containing mollusks and foraminifers with ages ranging from Late Cretaceous to P ...
... granular massive turbidites and conglomerate beds that have a lenticular geometry, which are most likely the slope-channel fill deposits. Junipero Serra Peak West of Junipero Serra Peak there is a poorly exposed outcrop containing mollusks and foraminifers with ages ranging from Late Cretaceous to P ...
Title
... University of Arizona, Walter C. Pitman III of Lamont-Doherty Geological (Earth) Observatory, Thomas W. C. Hilde of Texas A&M University and I had first considered the problem in the 1970s. The target was not a small one. We had predicted from geophysical data that an area in the western Pacific the ...
... University of Arizona, Walter C. Pitman III of Lamont-Doherty Geological (Earth) Observatory, Thomas W. C. Hilde of Texas A&M University and I had first considered the problem in the 1970s. The target was not a small one. We had predicted from geophysical data that an area in the western Pacific the ...
Prologue - Royal Society
... and gelatinous plankton. I would probably have thought him mad. Nothing could have seemed less likely. And yet, less than twenty-five years later, most serious marine scientists predict just such a fate. We can already see it happening. Eleven years after our honeymoon dive, in a foretaste of a warm ...
... and gelatinous plankton. I would probably have thought him mad. Nothing could have seemed less likely. And yet, less than twenty-five years later, most serious marine scientists predict just such a fate. We can already see it happening. Eleven years after our honeymoon dive, in a foretaste of a warm ...
CONTROLS ON HYDROCARBON GENERATION IN THE
... Parmeener Supergroup (Reid et al, this volume). The basal succession consists of 0450m of tillite deposited unconformably on eroded highlands formed after Devonian deformation. The remainder of the Lower Parmeener Supergroup is mainly fossiliferous glacimarine siltstones, sandstones and limestones. ...
... Parmeener Supergroup (Reid et al, this volume). The basal succession consists of 0450m of tillite deposited unconformably on eroded highlands formed after Devonian deformation. The remainder of the Lower Parmeener Supergroup is mainly fossiliferous glacimarine siltstones, sandstones and limestones. ...
metamorphism associated with extensional rifting of Gondwana
... limestone sequences in the early late Cretaceous in support of their hypothesis. Many of the anomalous features of the premier flysch are also evident in the basinal sequences further east in the southern Aegean and Turkey (Fig. 3). In south-west Turkey, Syrna and Tilos, and other small islands of t ...
... limestone sequences in the early late Cretaceous in support of their hypothesis. Many of the anomalous features of the premier flysch are also evident in the basinal sequences further east in the southern Aegean and Turkey (Fig. 3). In south-west Turkey, Syrna and Tilos, and other small islands of t ...
Plate tectonic evolution of the southern margin of
... were sutured to the Eurasian margin, closing the Paleotethys Ocean. A Jurassic – Cretaceous north-dipping subduction boundary was developed along this new continental margin south of the Pontides, Transcaucasus and Iranian plates. The subduction zone trench-pulling effect caused rifting, creating th ...
... were sutured to the Eurasian margin, closing the Paleotethys Ocean. A Jurassic – Cretaceous north-dipping subduction boundary was developed along this new continental margin south of the Pontides, Transcaucasus and Iranian plates. The subduction zone trench-pulling effect caused rifting, creating th ...
Geologic Time - Kean University
... distant time life on Earth was considerably different than it is today. Geologic time is unevenly divided into the most recent 12% of Earth history that is represented by rocks with fossils and deep time, the much longer interval that occurred before the evolution of organisms with hard skeletons su ...
... distant time life on Earth was considerably different than it is today. Geologic time is unevenly divided into the most recent 12% of Earth history that is represented by rocks with fossils and deep time, the much longer interval that occurred before the evolution of organisms with hard skeletons su ...
Geologic Time
... distant time life on Earth was considerably different than it is today. Geologic time is unevenly divided into the most recent 12% of Earth history that is represented by rocks with fossils and deep time, the much longer interval that occurred before the evolution of organisms with hard skeletons su ...
... distant time life on Earth was considerably different than it is today. Geologic time is unevenly divided into the most recent 12% of Earth history that is represented by rocks with fossils and deep time, the much longer interval that occurred before the evolution of organisms with hard skeletons su ...
Geology of Paraná - Mineropar
... Africa as the South Atlantic Ocean spread, took place in the Cretaceous. As part of the breakup process, extensive, up to 1,500 m of superposed basalt flows covered more than 1,200,000 km2 of the Paleozoic sedimentary rocks of the Paraná Basin. The remarkably fertile soil known as Terra Roxa derives ...
... Africa as the South Atlantic Ocean spread, took place in the Cretaceous. As part of the breakup process, extensive, up to 1,500 m of superposed basalt flows covered more than 1,200,000 km2 of the Paleozoic sedimentary rocks of the Paraná Basin. The remarkably fertile soil known as Terra Roxa derives ...
Field Report - Indus Experiences
... exploit. Once a little organic matter has accumulated, plants can soon acquire a root-hold. Continued uplift means that plants have to adapt, gradually, to changes in altitude as well as in the topography of their surroundings, with all that means for temperature and availability of light, water and ...
... exploit. Once a little organic matter has accumulated, plants can soon acquire a root-hold. Continued uplift means that plants have to adapt, gradually, to changes in altitude as well as in the topography of their surroundings, with all that means for temperature and availability of light, water and ...
The Geological Time Scale
... 1. Of the total length of your timeline, how much does the longest era take up? What percentage of the Earth’s history is this? ...
... 1. Of the total length of your timeline, how much does the longest era take up? What percentage of the Earth’s history is this? ...
The Sevier Orogeny The Sevier orogeny took place at about the
... The Sevier orogeny took place at about the same time as the Laramide orogeny towards the end of the Cretacious and into the Tertiary from ~70-35 Ma. The Sevier orogeny happened largely due to the same regional stresses that created the Laramide. What distinguishes the Sevier from the Laramide, howev ...
... The Sevier orogeny took place at about the same time as the Laramide orogeny towards the end of the Cretacious and into the Tertiary from ~70-35 Ma. The Sevier orogeny happened largely due to the same regional stresses that created the Laramide. What distinguishes the Sevier from the Laramide, howev ...
GIS-based Reconstruction of Pangaea with Recent
... - From a geological viewpoint these inland seas appear to be oceanic crust contained inside continental crust, and it is likely that they were connected to the Panthalassa Ocean by the sea. During the Permian period, about half of the Pangaean continent was under water. □ This study shows that Panga ...
... - From a geological viewpoint these inland seas appear to be oceanic crust contained inside continental crust, and it is likely that they were connected to the Panthalassa Ocean by the sea. During the Permian period, about half of the Pangaean continent was under water. □ This study shows that Panga ...
Petroleum Prospects of Lamu Basin, South
... temperature index determinations for coastal wells indicate that the oil window is generally located at depths greater than 3000 m, due to the low geothermal gradient associated with the great sediment thickness in this part of the Lamu basin (Rop, 2003; NOCK, 1995). The present day knowledge indica ...
... temperature index determinations for coastal wells indicate that the oil window is generally located at depths greater than 3000 m, due to the low geothermal gradient associated with the great sediment thickness in this part of the Lamu basin (Rop, 2003; NOCK, 1995). The present day knowledge indica ...
alberta dinosaur fact sheet
... before or since. It is also exceptional as it is a 3D, uncrushed specimen and the bone is not actually filled in with mineral matter. It also has stomach contents and skin preserved. 2) A pterosaur leg bone with the tooth of a small predatory dinosaur embedded in it. This is from Dinosaur Provincial ...
... before or since. It is also exceptional as it is a 3D, uncrushed specimen and the bone is not actually filled in with mineral matter. It also has stomach contents and skin preserved. 2) A pterosaur leg bone with the tooth of a small predatory dinosaur embedded in it. This is from Dinosaur Provincial ...
Mesozoic
The Mesozoic Era /mɛzɵˈzoʊɪk/ is an interval of geological time from about 252 to 66 million years ago. It is also called the Age of Reptiles, a phrase introduced by the 19th century paleontologist Gideon Mantell who viewed it as dominated by reptiles such as Iguanodon, Megalosaurus, Plesiosaurus and what are now called Pseudosuchia.Mesozoic means ""middle life"", deriving from the Greek prefix meso-/μεσο- for ""between"" and zōon/ζῷον meaning ""animal"" or ""living being"". It is one of three geologic eras of the Phanerozoic Eon, preceded by the Paleozoic (""ancient life"") and succeeded by the Cenozoic (""new life""). The era is subdivided into three major periods: the Triassic, Jurassic, and Cretaceous, which are further subdivided into a number of epochs and stages.The era began in the wake of the Permian–Triassic extinction event, the largest well-documented mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction which is known for having killed off non-avian dinosaurs, as well as other plant and animal species. The Mesozoic was a time of significant tectonic, climate and evolutionary activity. The era witnessed the gradual rifting of the supercontinent Pangaea into separate landmasses that would eventually move into their current positions. The climate of the Mesozoic was varied, alternating between warming and cooling periods. Overall, however, the Earth was hotter than it is today. Non-avian dinosaurs appeared in the Late Triassic and became the dominant terrestrial vertebrates early in the Jurassic, occupying this position for about 135 million years until their demise at the end of the Cretaceous. Birds first appeared in the Jurassic, having evolved from a branch of theropod dinosaurs. The first mammals also appeared during the Mesozoic, but would remain small—less than 15 kg (33 lb)—until the Cenozoic.