![Geology and Mineral Deposits of the Chulitna](http://s1.studyres.com/store/data/005104869_1-2f2700d1c99d6e0182937ae3a7b9d9d9-300x300.png)
Geology and Mineral Deposits of the Chulitna
... The Chulitna-Yentna mineral belt is defined principally on the basis of epigenetic metallic deposits. Secondary criteria that authenticate the belt are placer deposits derived from lodes within the belt and anomalous concentrations of metals in stream sediments. Localities of all known lodes and pla ...
... The Chulitna-Yentna mineral belt is defined principally on the basis of epigenetic metallic deposits. Secondary criteria that authenticate the belt are placer deposits derived from lodes within the belt and anomalous concentrations of metals in stream sediments. Localities of all known lodes and pla ...
Granitoids
... A few broad generalizations: 1) Most granitoids of significant volume occur in areas where the continental crust has been thickened by orogeny, either continental arc subduction or collision of sialic masses. Many granites, however, may postdate the thickening event by tens of millions of years. Ima ...
... A few broad generalizations: 1) Most granitoids of significant volume occur in areas where the continental crust has been thickened by orogeny, either continental arc subduction or collision of sialic masses. Many granites, however, may postdate the thickening event by tens of millions of years. Ima ...
Tectonic controls on the late Miocene–Holocene volcanic eruptions
... Tengchong volcanic Weld, NE–NNE-trending rift basins and NS-striking normal faults formed during the late Miocene–Pliocene. In addition, rapid exhumation of the neighboring mountains occurred at »6–5 Ma constrained by apatite Wssion track dating and its thermochronological modeling. At present, the ...
... Tengchong volcanic Weld, NE–NNE-trending rift basins and NS-striking normal faults formed during the late Miocene–Pliocene. In addition, rapid exhumation of the neighboring mountains occurred at »6–5 Ma constrained by apatite Wssion track dating and its thermochronological modeling. At present, the ...
Structural models of the Mediterranean lithospehre
... European plate below the Adria7c plate is fairly well evidenced by gently N–S dipping high-‐velocity lid and in accordance with scarce shallow seismicity and almost absent intermediate depth seismicity, as ...
... European plate below the Adria7c plate is fairly well evidenced by gently N–S dipping high-‐velocity lid and in accordance with scarce shallow seismicity and almost absent intermediate depth seismicity, as ...
The viability and style of the modern plate
... subduction below an 5-cm/yr overriding plate is followed by a sudden drop in vconv and vrms , as a result of the removed overriding plate motion. Subduction then slowly develops until the slab reaches 400 km depth, and the subduction is reinforced by the extra phase buoyancy of the exothermic olivin ...
... subduction below an 5-cm/yr overriding plate is followed by a sudden drop in vconv and vrms , as a result of the removed overriding plate motion. Subduction then slowly develops until the slab reaches 400 km depth, and the subduction is reinforced by the extra phase buoyancy of the exothermic olivin ...
Continents on the move
... or lie in oceans near the edges of continents? For example, there is a boundary across the middle of the Atlantic Ocean but in the Pacific Ocean, the boundary runs around the edges of North and South America and Asia. This fits with the ideas of ocean ridges (where plates move apart) and ocean trenc ...
... or lie in oceans near the edges of continents? For example, there is a boundary across the middle of the Atlantic Ocean but in the Pacific Ocean, the boundary runs around the edges of North and South America and Asia. This fits with the ideas of ocean ridges (where plates move apart) and ocean trenc ...
Geodynamics Workshop 2012 PROGRAM AND ABSTRACTS
... Recently, it was shown [3] that a thermo-chemical plume, which contains a fraction of 10-20% of eclogitic material derived from recycled oceanic crust, explains the observations much better. Due to the high eclogite density, these thermo-chemical plumes have lower buoyancy and thus generate much sma ...
... Recently, it was shown [3] that a thermo-chemical plume, which contains a fraction of 10-20% of eclogitic material derived from recycled oceanic crust, explains the observations much better. Due to the high eclogite density, these thermo-chemical plumes have lower buoyancy and thus generate much sma ...
Mantle plumes and dynamics of the Earth interior — towards a new
... According to this theory, the cool lithospheric slabs, gravity-sinking in the upper mantle, cumulate at the 660 km boundary and, subsequently, episodically “breaking through” the boundary, they submerge towards the core/mantle boundary (CMB). High viscosity of the lower mantle, confirmed, among othe ...
... According to this theory, the cool lithospheric slabs, gravity-sinking in the upper mantle, cumulate at the 660 km boundary and, subsequently, episodically “breaking through” the boundary, they submerge towards the core/mantle boundary (CMB). High viscosity of the lower mantle, confirmed, among othe ...
The landslide
... falls, some of which may have generated tsunamis. The first published account of a landslide in Greenland is that of Steenstrup (1900), who recorded an event that occurred in 1870 near Ujarasussuk on the north coast of Disko. A mudflow with large floating blocks of basalt built a lobe into the sea a ...
... falls, some of which may have generated tsunamis. The first published account of a landslide in Greenland is that of Steenstrup (1900), who recorded an event that occurred in 1870 near Ujarasussuk on the north coast of Disko. A mudflow with large floating blocks of basalt built a lobe into the sea a ...
Full-text PDF (final published version)
... 2003; Anbar, 2004; Pearce et al., 2008; Gordon et al., 2009). In contrast to many previous mass-dependent isotope systems, Mo behaves as an incompatible and refractory element in magmatic systems. Its chemical properties result in significant changes in its charge and coordination during low- and hig ...
... 2003; Anbar, 2004; Pearce et al., 2008; Gordon et al., 2009). In contrast to many previous mass-dependent isotope systems, Mo behaves as an incompatible and refractory element in magmatic systems. Its chemical properties result in significant changes in its charge and coordination during low- and hig ...
The single largest oceanic plateau: Ontong Java–Manihiki–Hikurangi
... the Ontong Java Plateau (OJP) was emplaced ca. 120 Ma, with a much smaller magmatic pulse of ca. 90 Ma. Of similar age and composition, the Manihiki and Hikurangi Plateaus (MP and HP) are separated from the OJP by ocean basins formed during the Cretaceous long normal magnetic period. I present new s ...
... the Ontong Java Plateau (OJP) was emplaced ca. 120 Ma, with a much smaller magmatic pulse of ca. 90 Ma. Of similar age and composition, the Manihiki and Hikurangi Plateaus (MP and HP) are separated from the OJP by ocean basins formed during the Cretaceous long normal magnetic period. I present new s ...
1 Basic Principle of Geology of Iraq Definition: The geology of Iraq
... younger from bottom to top respectively. The missing ages (those ages that have not representative Lithology) are expanded and shown on the column (see figure below). ...
... younger from bottom to top respectively. The missing ages (those ages that have not representative Lithology) are expanded and shown on the column (see figure below). ...
Satellite gravity anomalies and crustal features of the
... in Table 1. The seismic sequence stratigraphic boundary Oligocene (O) and structural unconformities of upper Miocene (A), lower Pliocene (AA) and upper Pleistocene (B) and seafloor are correlated to ODP Leg 116 results10,11,22. ...
... in Table 1. The seismic sequence stratigraphic boundary Oligocene (O) and structural unconformities of upper Miocene (A), lower Pliocene (AA) and upper Pleistocene (B) and seafloor are correlated to ODP Leg 116 results10,11,22. ...
Geomorphic and Tectonic Implications of the Post
... 2Vof sanidine, and chemical composition (Epis and Chapin, 1974). The age of the tuff is corroborated by an early Oligocene vertebrate fauna in the overlying Castle Rock Conglomerate (Richardson, 1915; Izett and others, 1969). The tuff rests on an erosion surface carved on the Dawson Formation of Lat ...
... 2Vof sanidine, and chemical composition (Epis and Chapin, 1974). The age of the tuff is corroborated by an early Oligocene vertebrate fauna in the overlying Castle Rock Conglomerate (Richardson, 1915; Izett and others, 1969). The tuff rests on an erosion surface carved on the Dawson Formation of Lat ...
On the Driving Forces of Plate Tectonics
... Table 3 presents a comparison between the computed relative angular velocities and those of Chase (1972), for all plate pairs for which Chase had a reasonable number of measurements of both rate and direction. The agreement between computed and observed motions seems tolerable in view of the highly ...
... Table 3 presents a comparison between the computed relative angular velocities and those of Chase (1972), for all plate pairs for which Chase had a reasonable number of measurements of both rate and direction. The agreement between computed and observed motions seems tolerable in view of the highly ...
The tectonic regime along the Andes: Present
... toward or away from the trench line within an asthenospheric reference frame (Dewey 1980). This is correct only in a passive mantle model (Scholz and Campos 1995), because if a global westward motion of the lithosphere is considered these premises are not valid (see discussion in Doglioni et al. 200 ...
... toward or away from the trench line within an asthenospheric reference frame (Dewey 1980). This is correct only in a passive mantle model (Scholz and Campos 1995), because if a global westward motion of the lithosphere is considered these premises are not valid (see discussion in Doglioni et al. 200 ...
Regional anomalies of sediment thickness, basement depth and
... in this study, but we also find evidence for three more localized and shorter-lived pulses of volcanism. These pulses formed conjugate structures comprising the Milne Seamounts and Azores-Biscay Rise (at f 75– 40 Ma), the Southeast Newfoundland Ridge and Madeira-Tore Rise ( f 130 – 110 Ma), and the ...
... in this study, but we also find evidence for three more localized and shorter-lived pulses of volcanism. These pulses formed conjugate structures comprising the Milne Seamounts and Azores-Biscay Rise (at f 75– 40 Ma), the Southeast Newfoundland Ridge and Madeira-Tore Rise ( f 130 – 110 Ma), and the ...
[Download the PDF]
... tact with the lower mantle, but this now seems too deep. However, as long as there are roots instead of asthenosphere beneath at least the Precambrian nuclei of the continents, which is evident from studies of seismic anisotropy (Silver, 1996), it is dicult to avoid the conclusion that asthenospher ...
... tact with the lower mantle, but this now seems too deep. However, as long as there are roots instead of asthenosphere beneath at least the Precambrian nuclei of the continents, which is evident from studies of seismic anisotropy (Silver, 1996), it is dicult to avoid the conclusion that asthenospher ...
Mantle Convection and Global Sea Level: Implications for the
... over the asthenosphere (Figure 1, Schubert and Reymer, 1988) to calculate the sea level. Thus time histories of the total volume of continental plates and their density versus depth profiles are required for the sea level calculation. We assume a constant thickness of 200 km for the continental lith ...
... over the asthenosphere (Figure 1, Schubert and Reymer, 1988) to calculate the sea level. Thus time histories of the total volume of continental plates and their density versus depth profiles are required for the sea level calculation. We assume a constant thickness of 200 km for the continental lith ...
“The “plate” model for the genesis of melting anomalies”
... the upper mantle, and within the lithosphere, respectively. Thin blue lines indicate plate boundaries. For additional maps and relevant resources, see Sandwell et al. (2005). ...
... the upper mantle, and within the lithosphere, respectively. Thin blue lines indicate plate boundaries. For additional maps and relevant resources, see Sandwell et al. (2005). ...
reprint
... east-west fast polarization directions, which is not observed. If an aseismic plate does extend here, as suggested by volcanism in western Patagonia (Gill 1981; Simkin et al. 1981), the splitting signal would be a combination of the subplate anisotropy, the mantle wedge anisotropy, and any lithosphe ...
... east-west fast polarization directions, which is not observed. If an aseismic plate does extend here, as suggested by volcanism in western Patagonia (Gill 1981; Simkin et al. 1981), the splitting signal would be a combination of the subplate anisotropy, the mantle wedge anisotropy, and any lithosphe ...
mesozoic successions of the betic and iberian ranges
... On top of these are Jurassic rocks corresponding to the carbonate sedimentation in extensive shelves protected by bioclastic bars and bioherms. The tectonic and sea level variations caused a great variety of domains and facies, and the subsequent stratigraphic unconformities with plenty of hiatus as ...
... On top of these are Jurassic rocks corresponding to the carbonate sedimentation in extensive shelves protected by bioclastic bars and bioherms. The tectonic and sea level variations caused a great variety of domains and facies, and the subsequent stratigraphic unconformities with plenty of hiatus as ...
Seismic wave speed structure of the Ontong
... speed geometry than ray based methods (Hung et al., 2004), reducing smearing, leading to higher amplitude and more constrained anomalies (Becker, 2012). While there has been discussions about the effectiveness of the finite frequency method in the applications to real data (Van Der Hilst and Maarten, ...
... speed geometry than ray based methods (Hung et al., 2004), reducing smearing, leading to higher amplitude and more constrained anomalies (Becker, 2012). While there has been discussions about the effectiveness of the finite frequency method in the applications to real data (Van Der Hilst and Maarten, ...
Geology
![](https://commons.wikimedia.org/wiki/Special:FilePath/Rock_cycle.gif?width=300)
Geology (from the Greek γῆ, gē, i.e. ""earth"" and -λoγία, -logia, i.e. ""study of, discourse"") is an earth science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change. Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.