bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Fai lure of the South Pass 70 "B" Platform Hurricane Camille
Authors: Sterling G.H. , Strohbeck E.E. 
Published: October 2008

ABSTRACT
In August of 1969, Hurricane Camille swept across the central Gulf of Mexico making landfall on the Mississippi Coast. This major storm caused the loss of many lives and considerable property damage was inflicted on the Gulf Coast from New Orleans to Biloxi. Shell Oil Company lost its South Pass 70 "B" Platform and Gulf Oil Company lost a similar platform in ft neighboring block.
This paper discusses the evidence gathered in an intensive after-the-fact study conducted to ascertain the cause of failure of Shell's platform. The data include: post-Camille survey of above-water damage at other platforms in the area, topographical surveys, side-scan sonar runs, soil borings, and detailed diving and underwater television surveys of the fallen structure.
The data conclusively show that the South Pass 70 "B" structure failed primarily because of sea floor soil movements.

INTRODUCTION
In June 1967, several Outer Continental Shelf (OCS) lease blocks in the Gulf of Mexico were offered for competitive lease bidding by the United States Geological Survey, an agency of the Federal Government. Shell Oil Company acquired the lease rights to South Pass Block 70 in that sale1 The block is located about 15 miles southeast of the Main Pass of the Mississippi River. Its location is shown in Figure 1.
Initial design studies for a bottom supported drilling and production platform for this area had been under way prior to the lease sale. Soon after confirmation of bid acceptance, soil borings were taken using the well-known wire1ine technique.2 While Shell's experience in the Delta region had led us to expect weak clay soils, the extent and depth of the very weak clays which were found in the boring program were unexpected. An immediate concern revolved around appropriate design approaches to withstand lateral and axial pile loadings. A second, and ultimately much more serious problem, was soon hypothesized; i.e., the soils were so weak that soil movements caused by slumping or sliding actions might take place. Thus, while the design proceeded, an extensive program of research and field work to evaluate the probability of sea floor movements was undertaken.
Because of the very weak near surface soils, the bottom of the structure was extended into the soil (see Figure 2). Although this extension provided for increased stability during installation and reduced lateral deflections under routine wave loading, the structure was not designed to resist a massive soil movement of the type which occurred.
In late 1968 and early 1969, three platforms were installed in the general area one in South Pass 61 by Gulf Oil Company and two in South Pass 70 by Shell Oil. The resulting oil field became officially known as the South Pass 61 Field. The two Shell structures were named South Pass 70 "A" and 70 "B" Platforms.
Finite Element Analysis A Basis for Sea-Floor Soil Movement Design Criteria
Authors: Arnold Peter 
Published: October 2008

ABSTRACT
The application of a recently proposed finite element analysis is presented as a basis for the development of wave induced sea-floor soil movement design criteria. Experience gained in the application of this analysis leads to the following conclusion: Failure to recognize the effects of pressure and cyclic loading on soil strength properties, and the influence of strength profile shape and gravity stresses can lead to unrealistic design criteria. However, used prudently as a basis for soil movement and foundation design criteria, the finite element analysis represents a significant improvement over slope stability analyses which are currently in use.

INTRODUCTION
Recent experience1,2 in the Mississippi Delta area of the Gulf of Mexico indicates that bottom pressures generated by storm waves can trigger large scale sea-floor soil movements. These movements can produce lateral forces on an offshore platform that exceed the magnitude of design level wind, wave, and current forces combined. The technology required to develop soil force and foundation design criteria can be divided into three elements:Limiting Equilibrium - What conditions are required to be present in order for soil movement to occur?Soil Response - What are the pattern and magnitudes of displacements and the state of stress in the soil during movement?Soil-Structure Interaction - How does the soil movement affect the platform?
This paper will concentrate on the conditions of limiting equilibrium and soil response, which are related to soil movements generated locally by wave bottom pressures. The soil-structure interaction problem is treated elsewhere3 The question of probability of occurrence, which includes an evaluation of wave occurrence and the relationships between wave kinematics and bottom pressures, is also of prime importance in the development of design criteria but is beyond the s cope of this paper.
A lower bound solution, employing a simplified finite element model, has recently been proposed4 to study the waveinduced soil movement problem. This static two-dimensional model includes the effects of large vertical deformations of the seafloor boundary and the nonlinear stress strain characteristics of the soil. This finite element analysis has the capability of resolving the questions of limiting equilibrium, pattern and magnitude of displacements, and state of stress, which are required in the development of design criteria. The validity of design criteria, which are developed using the results of any analytical model, will depend on at least three factors which are beyond the validity of the analytical model itself:Selection of input data, especially soil properties, which are representative of field conditions.Complete interpretation of the analytical results and their relationship to field response.Incorporation of field parameters, especially gravity forces due to bottom slope, which are not included in the analytical model.
State of the Art in Float-Overs
Authors: Seij Michel , de Groot Henk 
Published: October 2008

Abstract
The float-over deck installation is in use as an effective installation method since the eighties. The method has developed and the applicability has widened to heavier integrated decks and harsher environments such as West- Africa and West-Australia.
The paper describes the state of the art in float-over deck installations by an overview of a number of typical float-over operations. Each of these float-overs has a typicality related to:Integrated deck weight;Environment;Installation concept. The present state of the art has been reviewed in a SWOT analysis from a contractor's and operator's perspective. Strength, weaknesses, oppurtunities and threats have been summarized to identify a way forward for future developments.
Possibilities for the way forward to achieve the following objectives have been outlined in the paper:Improved workability;Reduced jacket slot requirements;Standardization to reduce early commitment requirements.

Introduction
Installing an integrated deck onto a jacket structure is an operation that has been executed by using semi submersible crane vessels and derrick barges already for many years. Offshore integration costs can be reduced since the integrated deck weight can be over above the capacity of (locally) available crane capacity.
The float-over deck installation is proving to be a competitive alternative for such an offshore installation operation. In recent years the concept of float-over deck installation has matured. With the help of a lengthening track record and benefits over lift operations, the float-over deck installation is taken into account as a reliable means of installing the assets. Since the float-over deck installation has been used only for a limited number of projects compared to the lifting operations performed by semi submersible crane vessel, improvements to the concept are still to be expected.

Float-over Deck Installation: Sequence
For better understanding of the advantages and dis-advantages of the float-over deck installation over semi submersible crane vessels, a brief introduction to the float-over concept is presented.

Load-Out
The load-out is the starting point of a float-over deck installation. The integrated deck will be build on-shore and needs to be loaded out onto the installation vessel. Load-outs can be performed either by self propelled modular trailers or by the use of skid tracks.
Figure 1 presents a skidded load-out of a 15.000 tons module onto self propelled installation vessel Blue Marlin. Figure 1: Skidded load-out of 15.000 tons module (available in full paper) Requirements for the load-out stage are governed by the following parameters:Integrated deck weight;Tidal range;Quayside dimensions.

Sea Transportation
After completion of the load-out, the integrated deck has to be seafastened on board the installation vessel prior to commencing sea transportation. One aspect of the transport that's always critical for a float-over transport is stability of the vessel.
Espirito Santo: The New Deepwater Frontier in Brazil
Authors: Bezerra Márcio Félix Carvalho , De Rossi Nery Vicente Milani 
Published: October 2008

Abstract
Petrobras has extensively acted in five simultaneous Exploration and Production frontiers in the Espirito Santo Basin, namely: gas in shallow water, light and heavy oil in deepwater, light oil in ultra deepwater and onshore. The oil and natural gas production has increased very fast over the last years; thus, contributing to the sustainability of the Brazilian scenario.
The new projects planned will require solid investments from Petrobras, in the order of US$ 9 billion up to 2011, applied mainly in the exploration and production areas. The turning point in the oil production is starting with the new deepwater production systems in the following fields:?Golfinho: (module 1 - FPSO Capixaba - 2006) and (module 2- FPSO Cidade de Vitoria -2007).?Jubarte: phase 1 (FPSO P-34 - 2006) and phase 2 (FPSO P-57 - 2010).
In 2006, the oil production will increase from 30 for 90 Mbopd.
Natural gas is another example of success. Production is expected to rise from the current 1.3 million m3/d to about 20 million m3/d by the end of 2008.
In order to reach these goals, Petrobras has invested in new infrastructure projects such as pipelines, processing plants and in the construction of a new port to support offshore operations. The company has also participated in research projects in partnership with the Federal University of Espirito Santo. These actions will consolidate a new cycle in the petroleum industry in Espirito Santo, the new deepwater frontier in Brazil.

A Little Bit of History
The performance of Petrobras in Espirito Santo State, located in southeastern Brazil, encompasses activities in the areas of the Espirito Santo Basin (onshore and offshore) and the north portion of the Campos Basin (offshore). The activities in the area initiated exactly 50 years ago (1957), with focus onshore, with the first discovery happening after a 10- year research period (1967). In 1968, in the Espirito Santo Basin, the first Brazilian offshore well was perforated (1-ESS- 01), in shallow waters (WD 47 m). Also after 10 years of work (1978), the Cacao Field appeared as the first offshore commercial discovery in the Espirito Santo Basin, at a water depth of 19 meters.
The onshore production initiated in 1973, reached the top production of 25 Mbopd in 1984, declining down to 9 Mbopd in 1998, when new fields were discovered in function of new technologies (seismic 3D). During this period, new wells were perforated in shallow waters (60 meters), leading to the discovery of two new non-associated gas fields: Cangoa (1988) and Peroa (1997).
In 1999, Petrobras started pursuing a new frontier in the area, perforating the first wildcat (1-ESS-90A) in deep waters. Hence, a new cycle begins.
In early 2001, the first commercial discovery took place in deep waters (Jubarte Field) in the north of the Campos Basin, followed by, in 2003, the discovery of light oil, also in deep waters, in the Espirito Santo Basin (Golfinho Field).
The Selection of Material to Avoid Fracture in Large Offshore Structure
Authors: Harrison J.D. 
Published: October 2008

ABSTRACT
Due to stress concentrations and residual and erection stresses it is essential that the weldment regions be able to deform plastically without prior failure from the inevitable defects present in these regions. The paper outlines factors affecting fracture resistance and possible methods of material selection. A description is given of some standard tests for assessing brittle fracture resistance. It then describes the preferred approach which employs full thickness fracture mechanics tests of realistic weldments in which either the plane strain fracture toughness, K1c or the crack opening displacement, COD, is measured. From these an allowable defect size may be calculated. The selection procedure aims at ensuring that this is large; so large that the fabricator can be sure of avoiding larger defects either by careful attention to the control of the welding procedure or by non-destructive testing. The validity of the selection procedure is checked by carrying out large scale tests and also by correlations with actual service failures.

INTRODUCTION
The number of failures of fixed offshore structures due to brittle fracture which have been reported is relatively few. For example, of the 2,000 or so fixed platforms in the Gulf of Merico, it is understood that approximately 20 have failed from all causes including fire, collision, etc. Brittle fracture, however, was the cause of a significant number of these, particu1ar examples being given by Carter et al.1
As time progresses oil is being sought offshore in increasingly hostile environments, such as the North Sea. Two basic factors lead to an increased risk of fracture in such areas over the risk in areas exploited so far. These are greater water depths and lower air and sea temperatures. The first of these factors leads to the following, all of which themselves tend to increase the risk of fracture:The wish to use increased thicknesses.The wish to use higher strength materials at high design stresses.Larger welds leading to a lower ductility.Greater fabrication difficulties leading to greater risk of defects occurring.Increased difficulty of inspection to locate critical defects.
Factors 1, 2 and 3 tend to lower the transition temperature as will be seen later. This, combined with the reduction in operating temperature already referred to, clearly leads to an increased risk of fracture.
Any method of selecting materials for offshore applications must take account of the factors affecting resistance to fracture. The present paper outlines these factors, outlines the two main philosophies and the testing techniques for the selection of fracture resistant materials and describe in more detail a proposed selection procedure.
Wind Power: Wind Farms of the Northern Gulf of Mexico
Authors: Schellstede Herman J. 
Published: October 2008

Abstract
The Northern Gulf of Mexico has the potential to provide a substantial power source for the United States. Presently, alternative energy is being pursued by governmental agencies and the public. Many ideas being developed to provide energy are flawed due to basic financial inefficiency. A good source of energy is one that is low cost, has a direct method of conversion into useable energy and is plentiful.
Of course, wind has been employed in many facets of human development throughout recorded history. In many cases, the design evolution of machinery development is directly related to the research funds expended. In the last sixteen years, offshore wind energy farms have been constructed in European coastal waters. Wind turbines designed for land use were joined with marine technology to create the initial offshore wind energy farms.
Initial wind assessments of the Northern Gulf of Mexico suggest areas conducive to wind turbine power generation. The shallow waters of the Gulf of Mexico make economic sense for wind farm developers. This paper outlines a direct, efficient and predictable method for the development of offshore wind farms in the Northern Gulf of Mexico, combining technology found in the oil and gas industry with wind turbine technology. This marriage of technologies results in an economic method of providing electrical power to the mainland with an extremely environmentally-proven system.
This paper outlines the excellent power potential of the United States southern coastline and describes the basic steps which are being taken to provide power to the United States electrical grid.

Introduction
The offshore waters of the southern coastline of the United States have the potential to provide a sizeable degree of the power requirements required by the United States. The coastline has a far-reaching continental shelf, in some areas extending 80 miles while having water depths less than 150 feet.
General wind assessments have been conducted for many decades. After 1950, more specific data became available due to oil exploration and marine activities. Along the Gulf Coast, there are many ports, industrial areas, cities and activity near the shoreline. Many people live near the coastline of the Gulf of Mexico. Many of the states' coastlines are considered "noneconomic" with respect to the power generation by wind. Their offshore waters exhibit some of the best wind resources in the United States.
Each state bordering the Gulf of Mexico regulates its own territorial waters. With the exception of Texas, all the territorial waters extend three miles offshore. The Texas territorial waters extend 10.2 miles offshore. Water bottoms beyond the territorial limit are regulated by the Minerals Management Service. Based on the Texas territorial waters and the length of the coastline, Texas was chosen by offshore wind developer W.E.S.T. as its first choice for a wind farm site. A particular location has been chosen south of Galveston, Texas.
Industry/Government Relations in Offshore Resource Develop
Authors: Craven John P. 
Published: October 2008

ABSTRACT
The paper compares the organization of the federal-industry relationship of a number of countries. This comparison is made against a hypothetical idealized nation which is organized to develop ocean resources in the best national interest. The paper demonstrates that of the nations examined, their ranking with respect to this idealized manager is as follows:Japan,Taiwan,Germany,France,Canada, andUnited States.
Federal support for ocean resource development in all nations falls into categories of support for (1) science, (2) technology, (3) systems acquisition and operation. In the idealized case, there is a measure of federal support in all three areas. This situation exists in Japan. In the most antithetical case, federal support is limited primarily to science and private industry and is prevented by law and custom from acting in concert to perform systems function. This situation exists in the United States.

INTRODUCTION
The description of any nation's endeavors to harvest the resources of the ocean is, at best, impressionistic involving, as it does, a myriad of bureaus and bureaucracies, corporations, and enterprises, research and development institutions, social and legal regimes and institutions, etc. A comparative description of a number of national endeavors to harvest the resources of the ocean must be equally impressionistic, since economic, social, political, legal and scientific regimes differ widely between different nations and are not therefore strictly comparable. Despite the inability to describe national organization for development of ocean resources or to compare them, the actual endeavors--private, national, and international-will, in fact, determine who develops the ocean resources, how they are developed, whether the resources are conserved or wasted, the distribution of economic wealth derived there from, etc. Some attempt, no matter how impressionistic, ought therefore to be made to assess and compare national endeavors as a guide to technology development, as a benchmark against which to measure changes or proposed changes in national policy, as a predictor of the trend and pace of ocean development, etc.
This paper undertakes to make such a comparative survey and to derive from it some measure of the relative pace and efficiency of the collective international effort to enjoy the resources of the ocean.
In order to accomplish this comparative study, an idealization will be employed-that of a hypothetical nation which is organized so that its government can perform as a system manager to optimize the process of exploring for and exploiting ocean resources the benefit of the nation. Against thisidealization, the organization of a spectrum of other nations can be compared and an assess transment can be made of their effectiveness in carrying out the system's goal.
Improvement of Fatigue Life of Steel Catenary Risers and Oil Offloading Lines in West Africa
Authors: Bertaso Daniel , Hutt Graham , Wang Jue , Tews Paul 
Published: October 2008

Abstract
This paper describes a study of the methods for improving fatigue life of girth welds for applications in the demanding environment of West Africa such as offshore Oil Off-loading Lines (OOL's) and Steel Catenary Risers (SCR's).
Investigations concerned the various methods for improvement of the fatigue life including root and cap grinding and internal root re-melting.
The paper also describes the use of laser triangulation as a mean to verify root profile before and after improvement.

Introduction
Fatigue based designs and the need to deliver high performance welds are now common features of the flowline and riser systems required for the exploitation of the deep water reserves.
Such requirements typically apply to steel catenary risers, oil off-loading lines and increasingly, as a result of the mitigation measures needed for flowlines that are subject to pressure and temperature fluctuations (e.g. where there is a risk of lateral buckling).
The consequence of such designs is the need for fabrication methods and girth welding procedures which satisfy very demanding fatigue performance targets while offering acceptable levels of productivity.
Recent industry experience has demonstrated that the some existing welding methods such as pulsed GMAW and GTAW are able to deliver results that exceed previous expectation for single sided welds but only when used with great care. Unfortunately this enhanced performance has only been possible by implementing very stringent control measures on weld geometry and allowable defects these in turn dictate requirements that are very close to the capability limit of the contributory processes i.e. pipe production accuracy, weld reproducibility and NDT system capability.
The criticality is clearly demonstrated by reference to the figure 1 which shows that even a very small flaw (micro-fissure) can be implicated in fatigue crack initiation. In this example of a manually welded root in 28mm thick c-steel, the undetected cold lap had an initial height in the order of 100 micrometres.

Objectives
Based on the foregoing considerations, the author's Company initiated a programme of work to investigate fatigue life improvement techniques that could be used to complement existing high productivity welding methods. The objectives were to identify methods that could be used to be maintain the high performance but with greater repeatability and, ideally, with the relaxation of some of the controlling parameters.