Top PDF Regional mapping of the crustal structure in Southern California

Regional mapping of the crustal structure in Southern California

Regional mapping of the crustal structure in Southern California

Final discussion focuses on the relatively simple seismic velocity structure derived for the southern end of our transect beneath the southern part of Santa Clarita Valley and the San Fernando Pass areas. As shown on the geologic cross section the structure is much more com- plex than that of the seismic velocity model. Most notable is a lack of any signature for the San Gabriel fault, nor the Santa Susana-Sylmar thrust system. Nor is there any expression of the considerable basement relief beneath the Neogene strata of the area that is documented by drill hole data. In addition to the problem of poor resolution at the extremities of our seis- mic model, the most viable explanation for this is that upper plate crystalline rocks above the Vincent thrust of this region are also highly fractured and hydrated, and thus yield seismic ve- locities in a range below those of coherent basement rocks and overlapping with those of clastic sedimentary rocks. Such a textural state is born out by observations of crystalline rocks which constitute the western end of the San Gabriel Mountains, and which project westwards beneath the adjacent San Fernando Pass area. As noted earlier the history of upper plate crystalline rock fracturing, hydration and attenuation began during or shortly after initial schist underthrusting, and has been accentuated by Neogene to Recent extensional, strike-slip and compressional de- formations. The effects of this near pervasive textural and structural degradation of much of the Southern California region crystalline basement are well expressed along the entire length of our transect by their consistently low P-wave velocities as compared to what is known to typify texturally and structurally coherent continental basement rocks.
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Crustal Structure in Southern California from Array Data

Crustal Structure in Southern California from Array Data

Crust al stru cture and earthquake travel times In this thesis the Southern California array is used to deduce the gross features of Southern California crustal structure.. This, in turn[r]

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Surface Wave Propagation in the Western United States: I  Crustal Structure in the Western United States from Multi mode Surface Wave Dispersion  II  The Effects of the Continental Margin in Southern California on Rayleigh Wave Propagation

Surface Wave Propagation in the Western United States: I Crustal Structure in the Western United States from Multi mode Surface Wave Dispersion II The Effects of the Continental Margin in Southern California on Rayleigh Wave Propagation

Several paths in the Western United States were investigated using group veloc i ty dispersion obtained for 1the fundamental Love and Rayleigh modes with perIods extending to 50 seconds [r]

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Crustal structure of active deformation zones in Africa: Implications for global crustal processes

Crustal structure of active deformation zones in Africa: Implications for global crustal processes

Section 2 provides a broad-brush summary of the geodynamical context of active deformation in Africa. Section 3 outlines the role of magma intrusion during the fi rst 5 – 7 Myr of rifting in cratonic lithosphere, using examples from the southern sector of the Eastern (Gregory) rift. Sections 4 and 5 address the role of magmatism and thinning in the formation of crust transitional between continental and oceanic. The Horn of Africa is one of few areas worldwide where this transition is occurring, and comparisons with the well-studied Salton Trough and northern Gulf of California (e.g., Fuis & Mooney, 1990; Persaud et al., 2016) inform our understanding of magmatic modi fi cation along passive margins worldwide. In section 6, we journey across the continent, where warm asthenosphere rises beneath the eastern edge of the Congo craton and the southern margin of a preexisting Mesozoic rift zone. This linear belt of Cenozoic erup- tive volcanic centers, neither the CVL, exhibits the age progression, mechanical stretching, magmatic mod- i fi cation displayed in parts of East Africa nor along linear volcanic tracks in oceanic plates. Here too, volatiles have likely played a central role in magmatic modi fi cation of Africa ’ s crust. Section 7 presents a review of crustal structure and its relation to mantle dynamics beneath the Atlas Mountains where compressional tectonics may inhibit upward migration of melt, leading to the localized, linear trend of magmatism linked instead to the Canary Island hot spot. This integration of constraints on crustal structure beneath zones of active rifting and orogenesis in Africa shows that magma and volatiles are migrating from the astheno- sphere through the plates, modifying lithospheric rheology and signi fi cantly contributing to global carbon and water fl uxes.
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The imprint of crustal density heterogeneities on regional seismic wave propagation

The imprint of crustal density heterogeneities on regional seismic wave propagation

4.2 Random models of plausible Earth structure In the absence of detailed information on crustal density structure on regional scales, we base our numerical exper- iments on realisations of random Earth models. To ensure that the random models are plausible, we translate rms vari- ations in S velocity in the Anatolia model of Fichtner et al. (2013) into variations of P velocity and density, using the empirical velocity–density scaling of Brocher (2005). The plausibility of the random models is limited by three fac- tors: (i) the variability of regional-scale rms variations in S velocity, (ii) the poorly known amplitude spectrum of ve- locity and density variations in the crust, and (iii) the range of different velocity–density scalings proposed in the lit- erature. The rms variations in S velocity in the Anatolian crust are ∼ 260 m s −1 , with a horizontal correlation length of ∼ 200 km and a vertical correlation length of ∼ 20 km. These correlation lengths were used for most of the numerical ex- periments, except for those in Sect. 3.4, where we studied the effect of medium complexity. Similar S velocity variations on the order of ± 10 % over similar distances were found in tomographic studies of other regions, including the Iberian Peninsula (e.g. El Moudnib et al., 2015; Fichtner and Vil- laseñor , 2015), California (e.g. Shapiro et al., 2005; Tape et al., 2010), the Caribbean plate (e.g. Gaite et al., 2015), or East Asia (e.g. Chen et al., 2015). This suggests that the rms variations of S velocity variations with 200 km lateral and 20 km vertical correlation length are representative of real crustal structure at least in some regions.
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Mid crustal geodynamics of the southern central zone, Damara Orogen, Namibia

Mid crustal geodynamics of the southern central zone, Damara Orogen, Namibia

Two areas of well exposed mid-crustal structures in the axial zone of the Pan­ African Damaran orogenic belt show that basement has formed domes which have amoeboid forms on the scale of tens of km with steep sided overturned non-planar, non­ cylindrical geometry. These are surrounded by open to tight synclinal cover envelopes that converge at depressions between the domes. The domes are found in association with a strong regional WSW moderately plunging lineation. Strain analysis demonstrates that domes have formed in a moderately plunging constrictional field. Structural features which normally indicate polyphase evolution such as mesoscale fold interference patterns are rare and inconsistent. Regional structural form, described morphogically by cylindrical domains, is defined by one fabric S q /S j . Secondary fabric trajectories and mesoscale fold oreintations are controlled by domain scale structure and not regional deformation trends. Dome formation is thus interpreted as being the result of a simultaneous flow and buckling episode within the middle crust.
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The application of synthetic seismograms to the interpretation of crustal and upper mantle structure

The application of synthetic seismograms to the interpretation of crustal and upper mantle structure

The existence of relatively strong energy on the direct branch (a-a), coming from the low velocity zone below the "200 km" discontinuity, is difficult to explain. The a-a branch of the CAP8 model raytracing, extending to distances of the order of 1300 km, is dependent on the propagation of rays over a distance of several hundred kilometres in the CAP8 model layer (227km - 8.648 km/s, 230km - 8.646 km/s) which is three kilometres thick. Wave theory suggests that this branch would have insignificant energy. The prominent arrivals on this direct branch have been interpreted as indicating a positive velocity gradient in the low velocity zone underlying the "200 km" structure, but more data will be required to fully resolve this portion of the upper mantle velocity profile. The CAPRI model therefore has a positive velocity gradient at the source depth of this event, so that rays on this a-a branch leave the source travelling downwards, and are turned in the positive velocity gradient above the "325 km" discontinuity. The CAPRI travel time distance curve indicates that the ray theoretical arrivals on this a-a branch terminate around 1100 km, but the full wave synthetic seismogram shows that low-amplitude, low-frequency arrivals extend to a distance of 1500 km. These correspond to energy which has tunnelled through the "high velocity layer" below 200 km depth in the CAPRI model.
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SOUTHERN REGIONAL TECHNICAL COLLEGE

SOUTHERN REGIONAL TECHNICAL COLLEGE

The Institutional Effectiveness Committee (IE Committee) is a standing committee within the structure of the College. The Committee monitors the College’s research, evaluation, assessment, and planning processes. It also ensures that the results of research, evaluation, and assessment are used in planning and for the improvement of units, educational programs, and services. The Committee ensures that data is used in decision making and that planning and evaluation processes are in accordance with the requirements of the Technical College System of Georgia (TCSG) and the Southern Association of Colleges and Schools Commission on Colleges (SACSCOC). The Committee is composed of faculty and staff and serves as a source of input and feedback to the administration of the College and to the Vice President for Institutional Effectiveness (VPIE).
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SOUTHERN REGIONAL TECHNICAL COLLEGE

SOUTHERN REGIONAL TECHNICAL COLLEGE

Southern Regional Technical College will meet the evolving needs of tomorrow’s workforce by providing engaging and cost-effective educational opportunities, preparing learners for success, and promoting seamless, lifelong learning. Southern Regional Technical College will provide state-of-the-art, well-maintained, and safe facilities to further support an optimal student-learning environment.

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Equivalent source mapping of the lunar crustal magnetic field using ABIC

Equivalent source mapping of the lunar crustal magnetic field using ABIC

An objective scheme is presented for estimating the lunar crustal magnetic field from the LMAG (Lunar MAGnetometer) data of the SELENE (“KAGUYA”) spacecraft. Our scheme improves the equivalent source method in three respects. The first improvement is that the source calculation is performed simultaneously with detrending. The second is that a great number of magnetic charges (magnetic monopoles) are used as the equivalent sources. The third is that the distribution of the magnetic charges is detremined by the damped least squares method, and the optimum smoothness is determined objectively by minimizing Akaike’s Bayesian Information Criterion (ABIC). For testing the scheme, we apply it to the Lunar Prospector magnetometer data in the region centered at the Reiner Gamma magnetic anomaly. The magnetic field map at an altitude of 20 km is stably drawn from datasets for different altitudes (18 km and 34 km). The ABIC minimizing criterion successfully controls the smoothness due to the numerical damping and extracts as much information as possible from the given data. This scheme will help produce a coherent lunar magnetic anomaly map by integrating the observations from various altitudes of the SELENE and previous missions.
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Education University of Southern California Los Angeles, California Master of Music

Education University of Southern California Los Angeles, California Master of Music

“ Recording Arts Curricula: A Time for Adjustment” Paper presented at Music Entertainment Industry Educators Association Conference, April 2005, Miami, Fl. "Uses of Digital Audio W[r]

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Crustal structure in the Siwalik Himalayas using magnetotelluric studies

Crustal structure in the Siwalik Himalayas using magnetotelluric studies

There are very few geophysical studies in this region. Most of the understanding of the thrusts as well as the base- ment interactions are based on the gravity and seismic stud- ies and deep borehole stratigraphic studies conducted for oil and natural gas prospecting. The rugged terrain in the Siwa- lik hills makes any systematic studies rather prohibitive. In order to obtain the deep crustal configuration in this region and to delineate the depth extent of the various thrust zones, magnetotelluric (MT) studies were undertaken over an 80 km long linear profile between Una and Mandi.

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Varying Indian crustal front in the southern Tibetan Plateau as revealed by magnetotelluric data

Varying Indian crustal front in the southern Tibetan Plateau as revealed by magnetotelluric data

(magmatism and/or migmatization) and possible partial melting in the mid- to lower crust (Xu and Ma 2015). Geochronological and geochemical data for dioritic dykes in the southern Gangdese magmatic belt suggest that the magma source is dominated by partial melting of lithospheric mantle and is then subsequently contami- nated by crustal material during ascent (Ma et al. 2016). However, it is notable that xenocrysts in the dykes indi- cate a deep process with a heterogeneous source in the middle Eocene (41 Ma) and it appears difficult to deter- mine the present deep thermal structure. Geochemical data from Jiru Cu deposit located in the Gangdese por- phyry Cu belt suggest that the post-collisional Miocene porphyry intrusions were generated by partial melting of the subduction-modified lower crust (Yang et al. 2016). Also, the results indicate increasing of water content over 4  wt.% with fractional crystallization (Yang et  al. 2016) that would actively enhance the conductance and corre- sponding partial melting (Le Pape et al. 2015). Studies of porphyry Cu deposits also suggest that potassic magmas are probably related with partial melting of the thickened juvenile mafic lower crust or delaminated lower crust (Hou et al. 2011). Also, one of the prominent factors for the metallogenesis is the release of the high water con- tent on the breakdown of amphibole in eclogite and gar- net amphibolite during melting. On the other hand, the increase in the H 2 O content would induce partial melting
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How To Get A Degree At The University Of Southern California

How To Get A Degree At The University Of Southern California

The University of Southern California has an outstanding record of commitment to interna- tional education. From a small presence dur- ing our early history, our international enroll- ment grew to an average of 200 students by the 1930s. After declining international enroll- ments in the years surrounding World War II, USC began rebuilding and in 1951 began pro- viding specialized admission services to inter- national students. By 1964, more than 1,000 international students were enrolled at USC. Today, the Office of Graduate Admission serves thousands of prospective students each year by providing both general and specialized information and by maintaining the expertise necessary to evaluate academic records from the various educational systems around the world. The Office of Graduate Admission also issues the required eligibility certificates (I-20 or DS-2019) to admitted stu- dents so that they can apply for a visa to enter the United States.
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Southern California Readmissions Update Summit 2014

Southern California Readmissions Update Summit 2014

linDSay hollanD, mha, BS., Clinical Project Manager, Health Services Advisory Group of Cali- fornia. Lindsay Holland has seven years expericence working the healthcare quality field. Lindsay is currently employed by Health Services Advisory Group (HSAG-CA), the QIO for California, as a Clinical Project Manager, Care Transitions. Lindsay works with several healthcare providers across the state of California to improve care transitions. She specializies in community organizing and care coordination as a method to reduce hospital readmissions. She also has experience working on healthcare quality in nursing homes and healthcare-acquired infections in hospitals. Lindsay was recently featured in Hosptials and Health Networks and Everything Long Beach for successfully coordinating one of the largest care transitions meeting in Southern California.
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List of Participating Dentists Southern California Counties

List of Participating Dentists Southern California Counties

Ladera Ranch Laguna Hills Laguna Hills Laguna Nguel Laguna Niguel Laguna Woods Laguna Woods Lake Forest Lake Forest Los Alamitos Mission Viejo. Mission Viejo Mission Viejo[r]

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Southern California Men's Collegiate Gymnastics Association

Southern California Men's Collegiate Gymnastics Association

4. Release, waive, discharge and covenant not to sue Southern California United, Southern California Men’s Collegiate Gymnastics Association, its affiliated clubs and gymnastics schools, their respective administrators, directors, agents, coaches, and other employees of the organization, other participants, sponsoring agencies, sponsors, advertisers, and , if applicable, owners and leasers of premises used to conduct the event, all of which are hereinafter referred to as "releases" from any and all liability to each of the undersigned, his or her heirs and next of kin for any and all claims, demands, losses or damages on account of injury, including death or damage to property, caused or alleged to be caused in whole or in part by the negligence of the release's or otherwise.
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A Geophysical Study of the Salton Trough of Southern California

A Geophysical Study of the Salton Trough of Southern California

The major portion of the gravity study is based on a complete Bouguer anomaly map of the Salton trough of California and parts of the Peninsular Ranges and Mojave Desert province figure [r]

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Some Suggestions for Rock Gardens in Southern California

Some Suggestions for Rock Gardens in Southern California

The extent of the rock garden will of necessity determine somewhat the type of the plants which can be used in it, for some relationship between the size of the plants[r]

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New Subspecific Combinations for Southern California Plants

New Subspecific Combinations for Southern California Plants

This subspecies is restricted to Santa Cruz, Santa Rosa, and Santa Catalina Islands and to the coastal Santa Ynez and Santa Monica Mountains, from Santa Barbara County [r]

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