Tectónica e Bacias
... TS-III and TS-IV were deposited in much larger basins or subbasins than was TS-II, and the unconformity between them is small to non-existent (Olsen, 1997). TS-IV includes the widespread CAMP basalts that were erupted in a geologically short interval at ~202 Ma (e.g., Olsen et al., 1996; Olsen, 1999 ...
... TS-III and TS-IV were deposited in much larger basins or subbasins than was TS-II, and the unconformity between them is small to non-existent (Olsen, 1997). TS-IV includes the widespread CAMP basalts that were erupted in a geologically short interval at ~202 Ma (e.g., Olsen et al., 1996; Olsen, 1999 ...
Divergent Plate Boundaries - North Coast Distance Education
... across the South Pacific, ending in the Gulf of California, a total length of about 70,000 km. Without question, it is the greatest “mountain” system on Earth. The internal structures of the “mountains” of the oceanic ridge, however, are nothing like the mountains of the continents, which largely co ...
... across the South Pacific, ending in the Gulf of California, a total length of about 70,000 km. Without question, it is the greatest “mountain” system on Earth. The internal structures of the “mountains” of the oceanic ridge, however, are nothing like the mountains of the continents, which largely co ...
The deep subsurface biosphere in igneous ocean crust: frontier
... Elucidating the nature and function of ocean crustal microbial ecosystems is critical to understanding the global-scale storage and transfer of carbon, nutrients, and life-supporting metals over geological time. This understanding has implications for the early Earth, modern Earth, and perhaps other ...
... Elucidating the nature and function of ocean crustal microbial ecosystems is critical to understanding the global-scale storage and transfer of carbon, nutrients, and life-supporting metals over geological time. This understanding has implications for the early Earth, modern Earth, and perhaps other ...
tectonics - GeoKniga
... with depth. The data reveal that there are specific depths inside the Earth at which velocity abruptly changes and waves bend—these depths are called seismic discontinuities (Figure 14.3a and b). Seismic discontinuities divide the Earth’s interior into distinct shells; within a shell, seismic wave v ...
... with depth. The data reveal that there are specific depths inside the Earth at which velocity abruptly changes and waves bend—these depths are called seismic discontinuities (Figure 14.3a and b). Seismic discontinuities divide the Earth’s interior into distinct shells; within a shell, seismic wave v ...
Calculating plate movement and plate motion activity File
... vectors for sites within the North American plate have dropped to near zero - indicating that most points within the plate are not moving with respect to the plate itself. (Note that we said 'most' but not 'all.') Take a careful look at the model velocities in the westernmost part of North America ( ...
... vectors for sites within the North American plate have dropped to near zero - indicating that most points within the plate are not moving with respect to the plate itself. (Note that we said 'most' but not 'all.') Take a careful look at the model velocities in the westernmost part of North America ( ...
pdf
... magmatic activity. Subsequent to initial alkaline magmatism, localized mid-oceanic ridge basalts (MORB) magmatism was again replaced by basin-wide alkaline events, caused by a low degree of decompression melting due to tectonic delocalization of deformation. Such “off-axis” magmatism might be a comm ...
... magmatic activity. Subsequent to initial alkaline magmatism, localized mid-oceanic ridge basalts (MORB) magmatism was again replaced by basin-wide alkaline events, caused by a low degree of decompression melting due to tectonic delocalization of deformation. Such “off-axis” magmatism might be a comm ...
tethyan evolution of turkey: a plate tectonic approach
... Palaeo-Tethyan and a Neo-Tethyan, although they partly overlap in time. The PalaeoTethyan evolution was governed by the main south-dipping (present geographic orientation) subduction zone of Palaeo-Tethys beneath northern Turkey during the PermoLiassic interval. During the Permian the entire present ...
... Palaeo-Tethyan and a Neo-Tethyan, although they partly overlap in time. The PalaeoTethyan evolution was governed by the main south-dipping (present geographic orientation) subduction zone of Palaeo-Tethys beneath northern Turkey during the PermoLiassic interval. During the Permian the entire present ...
Evidence for iceberg armadas from East Antarctica
... define the 40Ar/39Ar age populations. The analytical error is about 1% (see supplementary data file in Appendix A), which is much less than the age differences between the source provinces (see below). Excess argon cannot be detected on an individual single-step fusion age, but the well-separated age ...
... define the 40Ar/39Ar age populations. The analytical error is about 1% (see supplementary data file in Appendix A), which is much less than the age differences between the source provinces (see below). Excess argon cannot be detected on an individual single-step fusion age, but the well-separated age ...
The Laramide Orogeny: What Were the Driving Forces?
... Laramide orogenesis. However, it is not apparent why ridge-push would only have driven orogenesis during the Laramide, as spreading rates were not anomalously high during this time. Although Africa and North America began to separate at ~180 Ma, the main phase of drift between Eurasia and North Amer ...
... Laramide orogenesis. However, it is not apparent why ridge-push would only have driven orogenesis during the Laramide, as spreading rates were not anomalously high during this time. Although Africa and North America began to separate at ~180 Ma, the main phase of drift between Eurasia and North Amer ...
The Laramide Orogeny - University of Nevada, Reno
... Laramide orogenesis. However, it is not apparent why ridge-push would only have driven orogenesis during the Laramide, as spreading rates were not anomalously high during this time. Although Africa and North America began to separate at ~180 Ma, the main phase of drift between Eurasia and North Amer ...
... Laramide orogenesis. However, it is not apparent why ridge-push would only have driven orogenesis during the Laramide, as spreading rates were not anomalously high during this time. Although Africa and North America began to separate at ~180 Ma, the main phase of drift between Eurasia and North Amer ...
The Geological Concept
... ofland considerably elevated above the adjacent country, and is usually found connected in long chains or ranges, but sometimes can be in the form of single, isolated eminences. From the point of view of physical geography, the same dictionary (op. cit.) adds that any portion of the earth's crust ri ...
... ofland considerably elevated above the adjacent country, and is usually found connected in long chains or ranges, but sometimes can be in the form of single, isolated eminences. From the point of view of physical geography, the same dictionary (op. cit.) adds that any portion of the earth's crust ri ...
Gabbroic Pegmatite Intrusions, Iberia Abyssal
... exhumation of mantle rocks was under way by 137 Ma and continued for 10–20 my (Whitmarsh & Wallace, 2001; Manatschal et al., 2002). Site 1070 lies >100 km outboard of Hobby High, with much of the intervening oceanic basement being serpentinized peridotite (Fig. 2). Linear magnetic anomalies in the v ...
... exhumation of mantle rocks was under way by 137 Ma and continued for 10–20 my (Whitmarsh & Wallace, 2001; Manatschal et al., 2002). Site 1070 lies >100 km outboard of Hobby High, with much of the intervening oceanic basement being serpentinized peridotite (Fig. 2). Linear magnetic anomalies in the v ...
Deep Sea Drilling Project Initial Reports Volume 80
... the eastern Appalachian border have been followed onshore by McKerrow and Cocks (1977) and Williams (1979), and offshore by Jacobi and Kristoffersen (1976). South of the Gulf of St. Lawrence, the structural zoning has been interpreted from gravity and magnetic data compiled by Haworth and Mclntyre ( ...
... the eastern Appalachian border have been followed onshore by McKerrow and Cocks (1977) and Williams (1979), and offshore by Jacobi and Kristoffersen (1976). South of the Gulf of St. Lawrence, the structural zoning has been interpreted from gravity and magnetic data compiled by Haworth and Mclntyre ( ...
Geology - Geostud
... INTRODUCTION The long-term geological evolution of the North Atlantic and its surrounding passive margins includes convergence and collision of Laurentia, Baltica, and Avalonia (Fig. 1) and the closure of the Iapetus Ocean, leading to the early Paleozoic Caledonian orogeny (Roberts, 2003; Gee et al. ...
... INTRODUCTION The long-term geological evolution of the North Atlantic and its surrounding passive margins includes convergence and collision of Laurentia, Baltica, and Avalonia (Fig. 1) and the closure of the Iapetus Ocean, leading to the early Paleozoic Caledonian orogeny (Roberts, 2003; Gee et al. ...
Proterozoic History
... Many, small crustal blocks characterized the Archean Earth. During the later part of the Archean Era, these gradually merged and grew to form larger masses. The Early Proterozoic Era is marked by the earliest formation of several large, rigid continents. It is now generally accepted that plate tecto ...
... Many, small crustal blocks characterized the Archean Earth. During the later part of the Archean Era, these gradually merged and grew to form larger masses. The Early Proterozoic Era is marked by the earliest formation of several large, rigid continents. It is now generally accepted that plate tecto ...
pacific ocean and cenozoic evolution of climate
... reduced carbon. Elucidating accurate descriptions of previous climate states throughout the Cenozoic can help us to understand and perhaps to forecast the consequences of the current anthropogenic greenhouse gas transient and to better quantify other feedbacks among different Earth systems. The Paci ...
... reduced carbon. Elucidating accurate descriptions of previous climate states throughout the Cenozoic can help us to understand and perhaps to forecast the consequences of the current anthropogenic greenhouse gas transient and to better quantify other feedbacks among different Earth systems. The Paci ...
Pacific Ocean and Cenozoic evolution of climate
... reduced carbon. Elucidating accurate descriptions of previous climate states throughout the Cenozoic can help us to understand and perhaps to forecast the consequences of the current anthropogenic greenhouse gas transient and to better quantify other feedbacks among different Earth systems. The Paci ...
... reduced carbon. Elucidating accurate descriptions of previous climate states throughout the Cenozoic can help us to understand and perhaps to forecast the consequences of the current anthropogenic greenhouse gas transient and to better quantify other feedbacks among different Earth systems. The Paci ...
Australian Journal of Earth Sciences - ePIC
... 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 ...
the caribbean plate and the question of its formation
... model assumes the formation of the Caribbean plate at the Galapagos hotspot in the Pacific Ocean during the Middle Cretaceous. Subsequently, the Caribbean plate moved along major strike-slip faults into a pre-existent Jurassic Proto Caribbean basin between North and South America. The Alternative mo ...
... model assumes the formation of the Caribbean plate at the Galapagos hotspot in the Pacific Ocean during the Middle Cretaceous. Subsequently, the Caribbean plate moved along major strike-slip faults into a pre-existent Jurassic Proto Caribbean basin between North and South America. The Alternative mo ...
GEOL 109 - Continuing Education
... life on earth. While it is impossible to discuss the evolution of life on earth without placing it in the context of the physical evolution of our planet, we also wanted to make this class accessible to students without a background in physical geology. Therefore, the class has been designed with a ...
... life on earth. While it is impossible to discuss the evolution of life on earth without placing it in the context of the physical evolution of our planet, we also wanted to make this class accessible to students without a background in physical geology. Therefore, the class has been designed with a ...
profiles
... All rights reserved. No part of this book may be reproduced, stored in a central retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, withouth the prior written permission of the publisher. Written by Dougal Dixon. Special thank ...
... All rights reserved. No part of this book may be reproduced, stored in a central retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, withouth the prior written permission of the publisher. Written by Dougal Dixon. Special thank ...
Revised Tectonic Evolution of the Eastern Indian Ocean
... All published plate tectonic models for the Australian-Antarctic plate pair imply improbable plate tectonic scenarios either in the vicinity of the Kerguelen Plateau/Broken Ridge or between Tasmania and Antarctica (Figure 1). Some models result in tectonically improbable and geologically unsupported ...
... All published plate tectonic models for the Australian-Antarctic plate pair imply improbable plate tectonic scenarios either in the vicinity of the Kerguelen Plateau/Broken Ridge or between Tasmania and Antarctica (Figure 1). Some models result in tectonically improbable and geologically unsupported ...
Plate Tectonics - The Open University
... geology of our planet. It has also affected the hydrosphere through the changes in the shape and size of the oceans, the ocean-atmosphere circulation, the configuration and extremities of the Earth's climate zones and, perhaps, even the nature of the biosphere and the course of the evolution of life ...
... geology of our planet. It has also affected the hydrosphere through the changes in the shape and size of the oceans, the ocean-atmosphere circulation, the configuration and extremities of the Earth's climate zones and, perhaps, even the nature of the biosphere and the course of the evolution of life ...
Early Ordovician rifting of Avalonia and birth of the Rheic Ocean: U
... Avalonia is the largest accreted crustal block in the Appalachian–Caledonian orogen and comprises Neoproterozoic–early Palaeozoic magmatic arc and sedimentary cover sequences that can be traced from the British Caledonides in England SW to Rhode Island (Fig. 1). Lithostratigraphic, isotopic, faunal, ...
... Avalonia is the largest accreted crustal block in the Appalachian–Caledonian orogen and comprises Neoproterozoic–early Palaeozoic magmatic arc and sedimentary cover sequences that can be traced from the British Caledonides in England SW to Rhode Island (Fig. 1). Lithostratigraphic, isotopic, faunal, ...
Thematic Article Tethyan ophiolites and Pangea break-up
... that the ocean drifting was active from the Triassic to the Middle Jurassic. The compressive phases, as early as during the Middle Jurassic, were when the drifting was still active and caused the ocean closure at the Jurassic–Cretaceous boundary and, successively, the formation of the orogenic belts ...
... that the ocean drifting was active from the Triassic to the Middle Jurassic. The compressive phases, as early as during the Middle Jurassic, were when the drifting was still active and caused the ocean closure at the Jurassic–Cretaceous boundary and, successively, the formation of the orogenic belts ...
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.