868 research outputs found

    Lineaments in basement terrane of the Peninsular Ranges, Southern California

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    The author has identified the following significant results. ERTS and Skylab images reveal a number of prominent lineaments in the basement terrane of the Peninsular Ranges, Southern California. The major, well-known, active, northwest trending, right-slip faults are well displayed; northeast and west to west-northwest trending lineaments are also present. Study of large-scale airphotos followed by field investigations have shown that several of these lineaments represent previously unmapped faults. Pitches of striations on shear surfaces of the northeast and west trending faults indicate oblique slip movement; data are insufficient to determine the net-slip. These faults are restricted to the pre-tertiary basement terrane and are truncated by the major northwest trending faults. They may have been formed in response to an earlier stress system. All lineaments observed in the space photography are not due to faulting, and additional detailed geologic investigations are required to determine the nature of the unstudied lineaments, and the history and net-slip of fault-controlled lineaments

    Fault tectonics and earthquake hazards in the Peninsular Ranges, Southern California

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    The author has identified the following significant results. ERTS and Skylab images reveal a number of prominent lineaments in the basement terrane of the Peninsular Ranges, Southern California. The major, well-known, active, northwest trending, right-slip faults are well displayed, but northeast and west to west-northwest trending lineaments are also present. Study of large-scale airphotos followed by field investigations have shown that several of these lineaments represent previously unmapped faults. Pitches of striations on shear surfaces of the northeast and west trending faults indicate oblique-slip movement; data are insufficient to determine the net-slip. These faults are restricted to the pre-Tertiary basement terrane and are truncated by the major northwest trending faults; therefore, they may have formed in response to an earlier stress system. Future work should be directed toward determining whether the northeast and west trending faults are related to the presently active stress system or to an older inactive system, because this question relates to the earthquake risk in the vicinity of these faults

    Fault tectonics and earthquake hazards in parts of southern California

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    The author has identified the following significant results. Four previously unknown faults were discovered in basement terrane of the Peninsular Ranges. These have been named the San Ysidro Creek fault, Thing Valley fault, Canyon City fault, and Warren Canyon fault. In addition fault gouge and breccia were recognized along the San Diego River fault. Study of features on Skylab imagery and review of geologic and seismic data suggest that the risk of a damaging earthquake is greater along the northwestern portion of the Elsinore fault than along the southeastern portion. Physiographic indicators of active faulting along the Garlock fault identifiable in Skylab imagery include scarps, linear ridges, shutter ridges, faceted ridges, linear valleys, undrained depressions and offset drainage. The following previously unrecognized fault segments are postulated for the Salton Trough Area: (1) An extension of a previously known fault in the San Andreas fault set located southeast of the Salton Sea; (2) An extension of the active San Jacinto fault zone along a tonal change in cultivated fields across Mexicali Valley ( the tonal change may represent different soil conditions along opposite sides of a fault). For the Skylab and LANDSAT images studied, pseudocolor transformations offer no advantages over the original images in the recognition of faults in Skylab and LANDSAT images. Alluvial deposits of different ages, a marble unit and iron oxide gossans of the Mojave Mining District are more readily differentiated on images prepared from ratios of individual bands of the S-192 multispectral scanner data. The San Andreas fault was also made more distinct in the 8/2 and 9/2 band ratios by enhancement of vegetation differences on opposite sides of the fault. Preliminary analysis indicates a significant earth resources potential for the discrimination of soil and rock types, including mineral alteration zones. This application should be actively pursued

    Analysis of pseudocolor transformations of ERTS-1 images of Southern California area

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    The author has identified the following significant results. Representative faults and lineaments, natural features on the Mojave Desert, and cultural features of the southern California area were studied on ERTS-1 images. The relative appearances of the features were compared on a band 4 and 5 subtraction image, its pseudocolor transformation, and pseudocolor images of bands 4, 5, and 7. Selected features were also evaluated in a test given students at the University of California, Los Angeles. Observations and the test revealed no significant improvement in the ability to detect and locate faults and lineaments on the pseudocolor transformations. With the exception of dry lake surfaces, no enhancement of the features studied was observed on the bands 4 and 5 subtraction images. Geologic and geographic features characterized by minor tonal differences on relatively flat surfaces were enhanced on some of the pseudocolor images

    Who Let the Elephant in the Room? Analyzing Race and Racism through a Critical Family Literacy Book Club

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    The purpose of this study was to interpret, investigate, and analyze how race, racism, and power are embedded and intertwined not only in society but also in the education system and in homes and communities. Specifically, through parent and student engagement during a series of book club meetings, I investigated how parents’ racial identities impacted how they created critical dialogue pertaining to issues of race, racism, and power with their children. Guided by critical race pedagogy, critical race theory (CRT) and CRT methodology, this study used race as a critical analytic lens to examine the lives and work of people of color and Whites as well as the roles their homes, schools, and communities played in the development of their racial and cultural identities. I conducted in-depth reflexive interviews and focus groups with high school freshmen and their parents to investigate their experiences as they maneuvered race-related processes and discourses in society, schools, home, and communities. Drawing from interviews, memos, field notes, and other forms of research data, I created composite characters, and I presented the findings of this study through a dramaturgical performance. Findings showed that parents created dialogues with their children about social and equity issues in “episodic” moments (our memory of experiences and specific events in time in a sequential form). Furthermore, because of their involvement in the book club parents and students gained a deeper critical understanding of race and racism as evidenced by the findings and reoccurring themes from the data. Throughout the book club, some of the students and parents possessed a colorblind approach when it came to race. Furthermore, implications are provided to support educators, policy makers, researchers, parents, and students in challenging and overturning racial practices in various social institutions such as homes and schools as we begin to address and challenge the perplexity and the systemic effects of racism while taking different approaches to foreground an anti-racist agenda

    Letter from L. Q. C. Lamar to W. S. Featherston. Undated

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    Letter sent from Marshall County; regarding the relationship between Lamar and Featherston, support for Featherston in U.S. Senate election, presidential appointment, filling appointed mission to Mexico, Colonel Cushman\u27s federal appointment. Envelope.https://egrove.olemiss.edu/ciwar_corresp/1306/thumbnail.jp

    Letter from L. Q. C. Lamar to Col. Van. H. Manning. 10 May 1876

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    Letter sent from Hernando, Mississippi; regarding support of Taylor in senate election, candidates for congressional election and preference for Taylor, Manning\u27s candidacyhttps://egrove.olemiss.edu/ciwar_corresp/1273/thumbnail.jp

    Vortex dynamics

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    Vortex flows of interest to aerodynamicists cover a wide range of scales from a fraction of an inch in boundary layer flows to many feet in wake flows. In many applications these flows are poorly understood and, due to their complexity, present a challenge both analytically and experimentally. Four topics representing the spectrum of experimental and analytical vortex research are presented
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