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- Type:
- Etd
- Description/Abstract:
- This paper consists of three parts. Part I is gravity wave growth, saturation and decay with height; part II reflection of gravity waves from critical layer using realistic background atmosphere and background wind; part III perturbation treatment of minor species' response to gravity waves. In part I by using Newtonian cooling and Rayleigh friction approximations and by considering only the average effects of turbulence on gravity waves we have derived an optical potential, with which we have studied the propagation of gravity waves and their reflections at every height level. We have found that reflections from higher level due to viscosity and heat conduction is so small that no ducting can be sustained. part II is the continuation of He Fan's work. In our work we adopt the same two parameter optical potential to model the gravity wave--critical layer interaction but we relaxed the conduction of isothermalness of the background and the linearity of the wind profile and we use the more realistic wind models, so our results should be more meaningful. We have found that the reflection coefficients of gravity waves from critical layer range from 5% to 25%, which should be measurable. In part III we develop a perturbation scheme with which it is possible to calculate the minor species response to any order in the linear gravity wave, including a secular component of the response which leads to wave-induced diffusion of minor species. Calculations to third order over a wide range of wave parameters show that the nonlinear effects can be substantial. A result is that care must be taken when analyzing data from minor species fluctuations, so that frequencies due solely to the nonlinear nature of the minor species response are not attributed to gravity waves.
- Creator/Author:
- Li, Xuerong.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1996
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- I conducted melting experiments with a basanite, two hawaiites (DVDP2 and 83415), and a phonolite from Mt. Erebus, Antarctic. All experiments were carried out a 1 atmosphere from 1224$\sp\circ$ to 1049$\sp\circ$C at oxygen fugacity near QFM buffer. I have tested two hypothesis: (1) can a basanite parent magma differentiate at low pressures to produce hawaiite and phonolite magmas, and (2) do the Mt. Erebus rocks represent low pressure differentiation of a parental basanitic magma. Microprobe analyses of glasses and coexisting crystals were used to test these hypotheses.
- Creator/Author:
- Gerke, Tammie Lee.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1995
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- The purpose of this dissertation were threefold: (1) to develop a taphonomically-based facies (taphofacies) model for a classic, modern carbonate system, the south Florida shelf; (2) to compare and contrast the south Florida taphofacies model to the only other published modern carbonate taphofacies model, that of Parsons (1992) study of the northeastern Caribbean; (3) to compare and contrast a taphofacies model developed from the total mollusc assemblage (pooled sample approach) to models that only evaluate taphonomic changes within a single taxon as it occurs in different environments.
- Creator/Author:
- Dent, Steven Richard.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1995
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- Metamorphism in the Ollo de Sapo Antiform, part of the Variscan Orogen in NW Spain, was controlled by local, complex interactions of deformation, granitoid intrusions, and regional low pressure metamorphic (LPM) gradient. Detailed analysis of mineral parageneses, in conjunction with geothermobarometry and one-dimensional thermal modeling, have been used to constrain pressure-temperature-deformation (P-T-D) paths for rocks in the antiform.
- Creator/Author:
- Briggs, William David.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1995
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- The Richmond Group (Late Ordovician) in the tristate region of southwestern Ohio, north-central Kentucky, and southeastern Indiana consists of a succession of clastic and carbonate sediments deposited on a prograding intracratonic ramp and distal clastic fan. Six regional depositional facies have been delineated during a detailed examination of cores, outcrops, and geophysical logs across a 325 by 350 km study area. The facies, informally designated Facies A through F, are assigned to depositional environments consisting of: a shale-dominated shale distal intracratonic ramp; mixed carbonate and shale proximal intracratonic ramp; shallow subtidal to supratidal intracratonic ramp, and shallow-water, distal clastic wedge; based on their sedimentologic and paleontologic characteristics. Regional cross sections of these facies indicate that the distal clastic wedge prograded from the east and that the intracratonic ramp prograded from the south. In addition, isopach maps indicate that the depocenter of the basin was located southeastern Indiana and southwestern Ohio.
- Creator/Author:
- Petersen, Daniel W.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1994
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- The Coalinga, California region contains massive amounts of diapirically emplaced deposits of serpentinite. The largest deposit, the New Idria Formation, forms the core of the Joaquin Ridge Anticline and outcrops over an elliptically-shaped 48-square mile area in a mountainous area 17 miles northwest of Coalinga and 15 miles west of the California Aqueduct constructed along the western margin of the San Joaquin Valley. The serpentinite deposit is in faulted diapiric contact with Cretaceous-aged sandstones and shales and became emergent approximately 17 to 20 million years ago in the Miocene era. Eroded asbestos-bearing sediment from this ultramafic deposit has been incorporated in late-Miocene and younger sedimentary formations in the central San Joaquin Valley region.
- Creator/Author:
- De Reamer, John Harris, Jr.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1994
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- The Miamitown shale has been considered an enigmatic unit in the upper part of an Edenian-Maysvillian sequence. A new look at Cincinnatian sequences reveals that this unit is actually an integral part of a complex sequence architecture. Three fourth-order sequences at the base of the Upper Ordovician in the Cincinnati area are formally named in stratigraphic order: (1) the Brent Sequence, comprising the Edenian Kope Formation; (2) the Riedlin Sequence comprising the Maysvillian Fairview, Miamitown and Bellevue formations; and (3) the Stonelick Sequence comprising the Maysvillian Corryville and Mt Auburn formations. A detailed study of the Riedlin Sequence in outcrops, cores and well logs between Cincinnati, Ohio, Ft Wayne, Indiana, and Indianapolis, Indiana, (13,000 km$\sp2$), reveals stacking patterns within the Riedlin Sequence that are comparable to those of a type-2 sequence. This interpretation contrasts with previous interpretations wherein Cincinnatian third- and fourth-order cycles are dominated by highstand systems tracts with thin or absent lowstand and transgressive deposits, or where these cycles are interpreted as parasequences or parasequence sets rather than sequences. The Miamitown Shale provides a testing ground for a new integrated cyclic, lithologic, and quantitative faunal method of correlating meter-scale fifth-order cycles. This has been accomplished within the 12 m interval surrounding the Miamitown Shale in the upper part of the Riedlin Sequence. First, using lithologic criteria alone, six shale-to-limestone cycles bounded by flooding surfaces were delineated and correlated between seven 12 m outcrop sections within a 30 km radius. Unusual fossil occurrences constrained correlations of cycles 3 & 4, and the presence of a dalmanellid, Heterorthina fairmountensis, showed that the flooding surface above cycle 3 lay 10 cm below the lithologic contact. Quantitatively-defined faunal clusters constrained correlations between all cycles, and revealed a major transition at the top of cycle 2, again below the lithologic contact. Finally, depth gradient fluctuations interpreted from ordination of faunal data suggest that the major transition at the top of cycle 2 is a transgressive surface, and that the middle part of cycle 3 includes the interval of maximum depth.
- Creator/Author:
- Dattilo, Benjamin Francis.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1994
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- A sedimentological study of the Morrowan/Atokan age Corbin Sandstone Member (Lee Formation) of the central Appalachian Basin and the Mansfield Formation of the Illinois Basin was undertaken.
- Creator/Author:
- Barnhill, Mark Leonard.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1994
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- Filtration theory was developed by engineers to model the removal of particulate matter from industrial gases. Recently, it has been used by biologists and paleo-biologists to model the capture of food particles by filter feeding organisms. The purpose of this study was to test paleosynecologic (biofacies-level) and paleoautecologic (species-level) models of crinoid distribution utilizing filtration theory. These models were tested by analyzing the crinoid faunas of three transgressive-regressive sequences from the Upper Pennsylvanian Lansing Group of midcontinent North America.
- Creator/Author:
- Holterhoff, Peter Fielding.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1993
- License:
- All rights reserved
-
- Type:
- Etd
- Description/Abstract:
- Stratigraphic, sedimentologic and petrographic studies of the Lower and Upper Cretaceous in northwest Sonora show that deposition of the Bisbee Group occurred at the northern margin of a back-arc marine basin, and of the El Chanate Group and El Charro volcanic complex in a closed continental foreland basin. This study also finds that the Proterozoic-Paleozoic formations in northwest Sonora (Caborca terrane) were not part of the Cretaceous landscape, thus raising doubts about the existence of the Mojave-Sonora megashear.
- Creator/Author:
- Jacques Ayala, Cesar.
- Submitter:
- UC Libraries
- Date Uploaded:
- 03/26/2018
- Date Modified:
- 03/26/2018
- Date Created:
- 1993
- License:
- All rights reserved