The effects of source lithology, transport, deposition and sampling scale on the composition of southern California sand

The Transverse Ranges of southern California represent an uplifted and variably dissected Mesozoic magmatic arc, and Mesozoic to Holocene sedimentary and volcanic strata deposited in convergent and transform tectonic settings. Modern sand within part of the Western Transverse Ranges represents: first-order sampling scale of the Santa Monica and the San Gabriel Mountains; second-order sampling scale of the Santa Clara River draining both mountain ranges; and third-order sampling scale of the beach system between the mouth of the Santa Clara River and the eastern Santa Monica Mountains, and turbidite sand of the Hueneme-Mugu submarine fan. Source lithology includes plutonic and metamorphic rocks of the San Gabriel Mountains, and sedimentary and volcanic rocks of the Santa Monica Mountains. First-order sands have large compositional variability. Sand from local coastal drainage of the Santa Monica Mountains ranges from basaltic feldspatholithic to quartzofeldspathic. Sand of the San Gabriel Mountains local drainages has three distinct petrofacies, ranging from metamorphiclastic feldspatholithic to mixed metamorphi/plutoniclastic and plutoniclastic quartzofeldspathic. Second-order sand is represented by the main channel of the Santa Clara River; the sand has an abrupt downstream compositional change, from feldspathic to quartzofeldspathic. Third-order sand (beaches and deep-sea turbidite samples) of the Santa Monica Basin is quartzofeldspathic. Beach sand is more quartz-rich than is Santa Clara river sand, whereas turbidite sand is more feldspar-rich than is beach sand. Deep-sea sand has intermediate composition with respect to second-order samples of the Santa Clara River and third-order samples of the beach system, suggesting that (1) the Santa Clara River is the main source of sediments to the marine environment; and (2) local entry points from canyons located near local drainages may generate turbidity currents during exceptional flood conditions. Petrologic data of modern sand of the study area are highly variable at first- and second-order scale, whereas third-order sand is homogenized. The homogenized composition of deep-marine sand is similar to the composition of most ancient sandstone derived primarily from the Mesozoic dissected magmatic arc of southern California. This study of the Western Transverse Ranges illustrates the effects of source lithology, transport, depositional environment, and sampling scale on sand composition of a complex system, which provides insights regarding actualistic petrofacies models.     

Sea-level and tectonic control of middle to late Pleistocene turbidite systems in Santa Monica Basin, offshore California

Small turbidite systems offshore from southern California provide an opportunity to track sediment from river source through the turbidity‐current initiation process to ultimate deposition, and to evaluate the impact of changing sea level and tectonics. The Santa Monica Basin is almost a closed system for terrigenous sediment input, and is supplied principally from the Santa Clara River. The Hueneme fan is supplied directly by the river, whereas the smaller Mugu and Dume fans are nourished by southward longshore drift. This study of the Late Quaternary turbidite fill of the Santa Monica Basin uses a dense grid of high‐resolution seismic‐reflection profiles tied to new radiocarbon ages for Ocean Drilling Program (ODP) Site 1015 back to 32 ka. Over the last glacial cycle, sedimentation rates in the distal part of Santa Monica Basin averaged 2–3 mm yr^?1, with increases at times of extreme relative sea‐level lowstand. Coarser‐grained mid‐fan lobes prograded into the basin from the Hueneme, Mugu and Dume fans at times of rapid sea‐level fall. These pulses of coarse‐grained sediment resulted from river channel incision and delta cannibalization. During the extreme lowstand of the last glacial maximum, sediment delivery was concentrated on the Hueneme Fan, with mean depositional rates of up to 13 mm yr^?1 on the mid‐ and upper fan. During the marine isotope stage (MIS) 2 transgression, enhanced rates of sedimentation of > 4 mm yr^?1 occurred on the Mugu and Dume fans, as a result of distributary switching and southward littoral drift providing nourishment to these fan systems. Longer‐term sediment delivery to Santa Monica Basin was controlled by tectonics. Prior to MIS 10, the Anacapa ridge blocked the southward discharge of the Santa Clara River into the Santa Monica Basin. The pattern and distribution of turbidite sedimentation was strongly controlled by sea level through the rate of supply of coarse sediment and the style of initiation of turbidity currents. These two factors appear to have been more important than the absolute position of sea level.     

Property-based redevelopment and gentrification: The case of Seoul, South Korea

The urban experiences of South Korea in times of its rapid urbanisation and economic growth show that wholesale redevelopment had been a dominant approach to urban renewal, leading to redevelopment-induced gentrification. This was led by a programme known as the Joint Redevelopment Programme, transforming urban space that was once dominated by informal settlements into high-rise commercial housing estates. This paper tries to explain how this approach was possible at city-wide scale in its capital city, Seoul. Through the examination of redevelopment processes in a case study neighbourhood, it puts forward three arguments. First, the development potential arising from the rent gap expansion through under-utilisation of dilapidated neighbourhoods provided material conditions for the sustained implementation of property-based redevelopment projects. Second, this paper critically examines the dynamics of socio-political relations among various property-based interests embedded in redevelopment neighbourhoods, and argues that external property-based interests have enabled the full exploitation of development opportunities at the expense of poor owner-occupiers and tenants. Third, South Korea had been noted for its strong developmental state with minimum attention to redistributive social policies. The Joint Redevelopment Programme in Seoul was effectively a market-oriented, profit-led renewal approach, in line with a national housing strategy that favoured increased housing production and home-ownership at the expense of local poor residents’ housing needs.     

Rethinking graduated citizenship: Contemporary public housing in Singapore

The ways in which citizenship and housing are implicated in states’ global city aspirations demonstrate significant path dependency and local contingency. This paper serves to broaden the literature that has been dominated by the Western neoliberal context. First, I argue that The Pinnacle@Duxton – a one-of-a-kind public housing project in Singapore – represents the developmental state’s attempt to graduate its homogeneous public housing landscape, providing for and subsidizing the aspirations of a segment of its increasingly affluent middle class to buy into the ideology of the global city. Second, I show how the graduation of public housing coupled with the exaggerated demand for such exclusive projects validates consumer preference pricing in contemporary public housing. This results in a geographical graduation of citizenship, where the bulk of the population is relegated to lesser options on the edges on the island, unable to fulfil their aspirations for global living. In so doing, I make two contributions to extant literature on housing and citizenship in the global city. One, graduating citizenship is not always a case of states realigning their relationship with their citizens to fit the terms of the market. Two, the denial of citizenship to the global city does not always manifest in terms of substantive rights. Appreciating the unique histories and ideologies underpinning housing policies in global cities is instrumental if the variegated meanings of global cities and the citizenships within are to be elucidated.     

Sea level controls on the textural characteristics and depositional architecture of the Hueneme and associated submarine fan systems, Santa Monica Basin, California

Hueneme and Dume submarine fans in Santa Monica Basin consist of sandy channel and muddy levee facies on the upper fan, lenticular sand sheets on the middle fan, and thinly bedded turbidite and hemipelagic facies elsewhere. Fifteen widely correlatable key seismic reflections in high-resolution airgun and deep-towed boomer profiles subdivide the fan and basin deposits into time-slices that show different thickness and seismic-facies distributions, inferred to result from changes in Quaternary sea level and sediment supply. At times of low sea level, highly efficient turbidity currents generated by hyperpycnal flows or sediment failures at river deltas carry sand well out onto the middle-fan area. Thick, muddy flows formed rapidly prograding high levees mainly on the western (right-hand) side of three valleys that fed Hueneme fan at different times; the most recently active of the lowstand fan valleys, Hueneme fan valley, now heads in Hueneme Canyon. At times of high sea level, fans receive sand from submarine canyons that intercept littoral-drift cells and mixed sediment from earthquake-triggered slumps. Turbidity currents are confined to ‘underfit’ talweg channels in fan valleys and to steep, small, basin-margin fans like Dume fan. Mud is effectively separated from sand at high sea level and moves basinward across the shelf in plumes and in storm-generated lutite flows, contributing to a basin-floor blanket that is locally thicker than contemporary fan deposits and that onlaps older fans at the basin margin. The infilling of Santa Monica Basin has involved both fan and basin-floor aggradation accompanied by landward and basinward facies shifts. Progradation was restricted to the downslope growth of high muddy levees and the periodic basinward advance of the toe of the steeper and sandier Dume fan. Although the region is tectonically active, major sedimentation changes can be related to eustatic sea-level changes. The primary controls on facies shifts and fan growth appear to be an interplay of texture of source sediment, the efficiency with which turbidity currents transport sand, and the effects of delta distributary switching, all of which reflect sea-level changes.     

Changes of lead and barium with time in California off-shore basin sediments

During ancient times the natural deposition fluxes of lead which can be leached with dilute acid from sediments in Santa Barbara, Santa Monica and San Pedro basins offshore from the Los Angeles Urban complex, were about 0.7, 0.1 and 0.2 μg Pb/cm² yr respectively. Since there was little difference in biological productivity in surface waters of these basins, it is proposed that clay is a major transport vehicle for sequestered soluble lead, which then explains why the lead deposition flux within the Santa Barbara basin was so much larger compared to the other basins. The fluxes of silicate mud in the basins in ancient times were about 92, 19 and 30 mg/cm² yr in Santa Barbara, Santa Monica and San Pedro basins respectively. Today deposition fluxes of acid soluble lead within these three basins are 3- to 9-fold greater, being about 2.1, 1.1 and 1.8 μg Pb/cm² yr respectively, partly in the form of directly deposited large sewage particles, which account for none, $\text{2}\text{3}$ and $\text{3}\text{4}$ of the total industrial lead deposition fluxes in the respective basins. Concentrations of leachable lead in varve dated sediment layers increase with time and isotopic compositions of these leads change in accordance with corresponding known changes of isotopic compositions of industrial lead in the Los Angeles atmosphere. Lead remaining in acid leached sediment residues originates from igneous and clay minerals, exhibiting no change in concentration or isotopic composition since pre-industrial times.Deposition fluxes of total barium in sediments among the three basins were proportional to mass deposition fluxes before 1950 in the same manner as for lead. Afterwards, there are barium concentration maxima with time in both Santa Monica and San Pedro Basin sediments which are attributable to industrial sewage rather than to episodic erosion from barium-rich sedimentary evaporite strata exposed locally along the shore. An increase of barium concentrations in present day Santa Barbara basin sediments may reflect dispersal of barium-rich drilling mud from local drilling operations.     

Housing strategies in low income urban communities in Accra,Ghana

As the rent-free compound housing system in Ghana gradually became unpopular, there was the need for state intervention in housing provision. Housing became an important part of the country’s developmental policies through state interventions prior to the late 1970s. The economic crises in 1979 forced the country to opt for Structural Adjustment Programme, compelling the state to relax on its efforts to provide housing for the public. The paper uses the mode of economic integration framework to discuss the various housing forms in the country. It argues, housing provision led by the private sector creates remarked differences between housing for the higher and lower income groups. The study uses two low income communities in Accra to explain different ways by which the urban poor in Ghana accommodate themselves amidst the country’s housing problems. The study concludes there is an alternative to the housing crises in the country which could be found in the public-private investments in the rental form of the compound housing system.     

Housing Policy Regime in Lithuania: towards liberalization and marketization

This paper reviews housing policy development in Lithuania in the light of previous literature which reinterprets Esping-Andersen’s work on welfare regimes and adopts it to study housing policy. It seeks to highlight the major features of the Lithuanian housing policy. The findings of this paper reveal that the Lithuanian housing regime exhibits many features which are common under the liberal one. Most significant of these are low de-commodification for those who have to buy or rent a home for the market price, increasing stratification based on income and the dominant position of the market in housing production, allocation and price determination. However, a detailed examination of the Lithuanian housing policy reveals that the housing policy system, despite having many features similar to the liberal one, has been operating in different social and economic settings as a result of unique historical experience of the communist housing policy (massive production of low quality apartment blocks during the communist era, which currently need substantial renovation) and consequently drastic changes in the housing field since 1990s (massive privatization of the housing stock and decentralization of the housing management system). The Lithuanian housing policy regime could be characterized as a regime with the higher owner-occupation compared to other welfare state regimes, but the lower economic power of the owners to take care of their property maintenance, repair and renovation.     

Warsaw under transformation: new tendencies in the housing market

The aim of this paper is to show how and in what sense the post-socialist transformation process has influenced the urban spatial structure of Warsaw with the help of empirical evidence dealing with housing. Therefore, the main focus of the study is the transformation of the housing market in the 1990s under social and economic restructuring process. The article comprises two parts: the first part involves the geographical development of the urban spatial structure within the context of housing market changes. In order to explain today's transformation, the system of socialist time is also discussed. In the second part emphasis is placed on the evidence of the transformation in urban space, dealing with new tendencies and challenging mechanisms in the housing market. The last period of transformation is also investigated in terms of changes in the urban space since housing is seen as an important factor of urban transformation. Hence, following the brief outline of historical development of the urban space housing market changes including the privatization of urban land is going to be the concern of the paper. The problems of the transformation and practical implementation of the privatization process are also discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

The use of carbon and sulfur isotopes as correlation parameters for the source identification of beach tar in the southern California borderland

Carbon and sulfur isotope ratios and total sulfur content are used to correlate beach tars depositing near Los Angeles with their probable sources. Analysis is confined strictly to the asphaltene fraction of petroleum owing to the insensitivity of this fraction to weathering processes.The δ¹³C, δ³⁴S and % S of the asphaltene fraction of natural offshore seep oils range from ?22.51 to ?23.20%., +7.75 to + 15.01%. and 4.45 to 8.27%, respectively. Values for local offshore production wells overlapped those for the natural seepage, ranging from ?22.10 to ?22.85%., ?2.96 to 13.90%., and 0.81 to 8.00%. Analytical values for these parameters show that tanker crudes imported into the area are not similar to the California oils. Analysis of the same parameters in beach tars collected during 1976–1977 indicates a close match with the potential source oils, thus it is concluded that these parameters are useful for identifying petroleum sources, even after 2–4 weeks of weathering. Results indicate that 55% of the tars in Santa Monica Bay are derived from natural oil seepage 150km to the northwest at Coal Oil Point, 26% are derived from natural oil seepage in Santa Monica Bay, and 19% are derived from unknown sources.Models of tar transport are inferred which are consistent with the seasonal deposition pattern. Tar from Coal Oil Point natural oil seeps is transported southward in the southern California gyre during the spring, summer and fall seasons, but probably undergoes northward transport during the winter season due to the surfacing of the Davidson Current. Tar from the Santa Monica Bay natural oil seeps moves onshore, but deposition rate seems to depend on seepage flow rate.     

Outcrop-scale acoustic facies analysis and latest Quaternary development of Hueneme and Dume submarine fans, offshore California

The uppermost Quaternary deposits of the Hueneme and Dume submarine fans in the Santa Monica Basin have been investigated using a closed-spaced grid of boomer seismic-reflection profiles, which give vertical resolution of a few tens of centimetres with acoustic penetration to 50 m. Acoustic facies integrated with geometry define six architectural elements, some with discrete subelements that are of a scale that can be recognized in outcrops of ancient turbidite systems. In the Santa Monica Basin, the relationship of these elements to fan morphology, stratigraphy and sediment source is precisely known.
The width of upper Hueneme fan valley has been reduced from 5 km since the last glacial maximum to 1 km at present by construction of laterally confined sandy levees within the main valley. The middle fan comprises three main subelements: thick sand deposits at the termination of the fan valley, low-gradient sandy lobes typically 5 km long and < 10 m thick, and scoured lobes formed of alternating sand and mud beds with many erosional depressions. The site of thickest lobe sediment accumulation shifts through time, with each sand bed deposited in a previous bathymetric low (i.e. compensation cycles). The lower fan and basin plain consists of sheet-like alternations of sand and mud with shallow channels and lenses.
Variations in the rate of late Quaternary sea level rise initiated changes in sediment facies distribution. At lowstand, and during the approximately 11 ka stillstand in sea level, the Hueneme Fan was fed largely by hyperpycnal flow from the Santa Clara River delta, depositing high sediment waves on the right hand levee and thick sandy lobes on the middle fan. At highstand of sea level, most turbidity currents were generated by failure of silty prodelta muds. In contrast, the smaller Dume Fan was apparently always fed from littoral drift of sand through a single-canyon point source.     

Family strategies in a neoliberal world: Korean immigrants in Winnipeg

South Korean immigration to Canada has increased since the East Asian economic crisis of the late 1990s. Korean immigrants in Winnipeg chose the city for many reasons: the introduction of the Provincial Nominee Program, structural changes in the home country, and individual family strategies to provide better educational opportunities for their children. This article examines how changes in the current wave of globalization, at both global and local scale, have affected the migration of Koreans to Winnipeg, Canada and how individual households chose their immigration destination. This study contributes to understanding of the less popular immigrant destinations of Canada using a multiscalar analysis that includes household level. In addition to economic purposes and children’s education, changes of life style can be an important reason for immigrant location choice. Overall, the neoliberal economy in South Korea has pushed many Koreans to move to other countries, and the globalization of the Canadian economy has pulled nomadic middle-class members from other countries.     

Manila’s metropolitan landscape of gentrification: Global urban development,accumulation by dispossession & neoliberal warfare against informality

A new regime of gentrification is dramatically restructuring Manila’s metropolitan landscape. Grounded upon an on-going neoliberal warfare of accumulation by dispossession, this gentrification serves as the fulfillment of postcolonial visions of a world class and modern metropolis through public–private arrangements and market-oriented developments but necessitates the systematic demolition of informal settlements, the home of the Manila’s urban poor and working class population. Through a mixed-methods approach, this paper examines gentrification’s spatial forms and trajectories and exposes context specific dynamics facilitating accumulation by dispossession. Using barangay (village)-level data on changes in population of informal households and median zonal values, I calculate for local measures of spatial autocorrelation and locate significant clusters of spatial shifts. Using the quantitative results plus field narratives and community histories, I triangulate local dynamics of accumulation by dispossession. What emerges is a sprawling gentrification process that, in producing a market-oriented metropolis, displaces and asphyxiates informal spaces. These accounts illustrate the contingencies of violence, neoliberal urbanism, colonial legacies of land regimes, and elite power in the production of a globally-competitive Manila. With other Global South megacities similarly competing in the global market, gentrification in Manila, with its expanding landscape of property accumulation and ’legitimized’ dispossession, is instructive of the emerging form of gentrification in the 21st century.     

Vulnerability and resistance to neoliberal environmental changes: An assessment of agriculture and forestry in the Biobio region of Chile (1974–2014)

This article examines the dynamics of double exposure, vulnerability, and resistance to neoliberal globalization and environmental change in the Chilean agricultural region of Biobio. By using climatic models and secondary Agricultural Census data from 1997 and 2007, we assess how Chilean neoliberal reforms have, since 1974, facilitated land use changes and forestry investments. We demonstrate that policy changes which incentivize forestry investments have reduced cultivated agricultural lands and native forest, and concentrated land in the hands of global agribusiness corporations. Compounding these issues, Biobio shows a climatic trend towards aridity coupled with an increasing demand for irrigation. Analyzing these conditions, we argue that the neoliberal globalization of regional agriculture under the context of climatic changes has produced a regional space of increasing vulnerabilities and uneven geographical development in Biobio. We particularly demonstrate that the Chilean mode of agricultural neoliberalization has been conducive to land dispossession—to the detriment of traditional agriculture —and has homogenized the biophysical landscape, replacing traditional crops and native forests with exotic species like pines and eucalyptus. We also examine how local producers are using resistance movements to cope with and contest neoliberal environmental changes. We conclude by evaluating the implications of these spaces of agricultural vulnerabilities and local resistances in the context of uneven geographical development at a regional and global scale.     

Effects of an Acute Hypoxic Event on Microplankton Community Structure in a Coastal Harbor of Southern California

Fish mortality and hypoxic events occur in many coastal and inland systems and may result from natural or anthropogenically mediated processes. The effects of consequent changes in water biogeochemistry have been investigated for communities of benthic invertebrates and pelagic metazoans. The responses of micro-plankton assemblages, however, have remained largely unstudied. The northern basin of King Harbor, a small embayment within Santa Monica Bay, CA, USA, suffered a massive fish kill in March 2011 as a consequence of acute hypoxia. Dissolved oxygen concentrations < 0.1 ml?l^?1 were measured in the northern basin of the harbor for several days following the mortality event, and a strong spatial gradient of oxygen was observed from the northern basin to waters outside the harbor. The microplankton community within King Harbor differed significantly from a diatom-dominated community present in neighboring Santa Monica Bay. The latter region appeared unaffected by physicochemical changes, induced by the fish kill, that were observed within the harbor. A trophic shift was observed throughout King Harbor from a photoautotrophic-dominated assemblage to one of heterotrophic forms, with relative abundances of bacterivorous ciliates increasing by more than 80 % in the most impacted part of the harbor. Significant changes in community structure were observed together with dramatically reduced photosynthetic yield of the remaining phytoplankton, indicating severe physiological stress during the extreme hypoxia.     

The competitive (dis)advantages of ecotourism in Northern Thailand

Ecotourism within protected areas is paradigmatically considered a neoliberal conservation strategy along with other market-based interventions that devolve authority to non-state actors, rely on market corrections to socio-environmental problems, and effectively try to “do more with less” (Dressler and Roth, 2011) or “sell nature to save it” (McAfee, 1999). However, the neoliberalisation of conservation is a path-based process that is shaped by local histories and on-the-ground engagements with different market forms, and a growing body of scholarship has demonstrated that there are significant gaps between “vision” and “execution” in neoliberal conservation. Through a case study of ecotourism in Ban Mae Klang Luang in Northern Thailand, this research approaches the question of why such programs often fail to reconcile environmental and economic concerns through an exploration of the internal contradictions in the governmentalizing processes embedded within market-led conservation projects. Specifically, I argue that the contradiction in encouraging both disciplinary environmentality and neoliberal environmentality ironically forces conservation and development interests into opposition. Furthermore, ecotourism’s deployment of neoliberal environmentality contributes to the exaggeration of inequality and individualism in the village, creating tensions among community members. Despite the win–win expectations of neoliberal philosophy in conservation policies, the contradictory logics involved call the long-term viability of such strategies into question.     

Local government reform,urban crisis and development in South Africa

The article aims to interpret the proposed reorganization of local government in South Africa and to examine its development implications in relation to the metropolitan area of Cape Town. The interpretation of reorganization draws particularly on DUNCAN and GOODWIN's suggestion (Int. J. Urb. Res.,6, 157–185, 1982) that reorganization represents an attempt to reimpose the state form. The article places the reorganization of local government in South Africa in the context of the current reform strategy, and argues that it is an element of a strategy which attempts to produce new forms of social relations, ordered to an increasing extent by the market mechanism. The local government strategy reflects this and also responds in particular to the crisis of legitimacy at local government level and in urban areas. This crisis has been precipitated not so much by forms of representation in local government, as by economic and political conditions in general. However, the reform of local government does not address these conditions, nor does it set up a system of local government in which they might be addressed. In fact, the attempt to reorder society on the basis of the determinants of the market and the resulting emphasis on wealth as a criteria of access to cities, services and power is likely to exacerbate the conditions of unemployment, poverty, spatial inequality and shortages of housing. In effect, therefore, local government reform concerns itself with little more than the management of urban areas in an attempt to contain manifest political problems.     

Is better to be a kayayei than to be unemployed: reflecting on the role of head portering in ghana’s informal economy

The implementation of neoliberal economic reforms with its resultant effects on rural agricultural economies has facilitated the migration of young girls from northern to southern Ghana to seek for alternative livelihoods in the urban informal economy as head porters (Kayayei). Using semi-structured questionnaires and interviews with 45 Kayayei in Makola and Agbogbloshie Markets, Accra, this study examines how migration as a livelihood strategy contributes to an improvement in the living conditions of young girls and their families. The paper also looks more closely into the pathways through which the livelihoods of these young female migrants may contribute to local economic development. The study highlights that Kayayei contribute to local economic development through market exchange and revenue generation, also there is significant perceived positive impact of head portering on standard of living of these young girls through improved access to income, health care and asset accumulation while their families benefit from remittances. The study concludes by advocating for the need to provide access to credit and skills training in enhancing the livelihood of Kayayei.     

Population pressure, agricultural intensification and changes in rural systems in Bangladesh

Sustainable agricultural growth is the key to rural system changes that include changes in rural bio-physical environment, economic infrastructure and social conditions. The present study has examined the temporal changes in 18 selected indicators of rural systems in Bangladesh during the period 1975-2000, and explored the influences of demographic, market forces, environmental, institutional and technological factors inducing and mediating such changes. An analysis of 64 district level published census data showed significant increase in agricultural intensity, cropping patterns, land productivity and farm income; decline in labor and technological productivities; and major improvement in rural housing, economic and social conditions during this period. Spatially, major agricultural growth and rural development were observed in districts with high population density, less constrained environments, and better access to markets, irrigation canals, and capital loans.     

Fault location and fault activity assessment by analysis of historic level line data, oil-well data and groundwater data, Hollywood area, California

Transecting the Los Angeles metropolitan area in a general E-W direction are major north-dipping reverse faults comprising the Santa Monica—Raymond Hill fault zone, a segment of the frontal fault system separating the Transverse Ranges from the Peninsular Ranges geomorphic provinces of southern California. Pleistocene or Holocene movement is evident along some segments of these faults, but urban development precludes accurate location and assessment of Quaternary movement by conventional mapping techniques. At present no conclusive evidence of Holocene surface rupture has been found onshore west of the Raymond Hill segment of the fault zone, but the geologic conditions and urban development in the area are such that the possibility of Holocene movement cannot be excluded at this time. Groundwater barriers in Pleistocene sediments are indicative of Quaternary faulting on the Santa Monica fault segment west of the Newport—Inglewood fault zone. Most literature indicates that movement along the Beverly Hills—Hollywood segment east of the Newport—Inglewood fault zone terminated in Late Miocene or Pliocene time, and there is no general agreement on the location of faults in this segment. However, recent work by the Division of Mines and Geology, by Geotechnical Consultants, Inc., and others suggests that the Santa Monica fault transecting the Hollywood area is associated with a zone of differential subsidence that varies from 100 to 400 m wide, depending on the resolution of repeated leveling survey data and with a groundwater barrier determined from analysis of oil-well and water-well data. Additional exploration is essential to test our present geologic model and to evaluate the earthquake hazard and seismic risk of faults in the area.