Recommendations on Testing Procedures at the Gladys McCall and Pleasant Bayou GeoPressured Test Wells

Nine possible testing procedures for the Gladys McCall and Pleasant Bayou geopressured fields are listed. Evidence is presented that shows that reduction in salinity due to shale water addition to Gladys McCall formation waters can be measured over a 2-year period, but water analyses will need to be done under strictly controlled laboratory conditions. Sidetrack coring of geopressured reservoirs after production appears to be the most effective way of estimating total volumes of compaction and shale water recharge of geopressured formations. Sidetrack coring of the Andrau ('C') sandstone in the Pleasant Bayou No. 2 well will provide the maximum amount of information on post-production changes in shales and sandstones. Three preferred testing procedures are suggested in order of decreasing scientific payback and cost. The best testing procedure is to continue testing the Gladys McCall well for 2 years, then to cut a sidetrack core and plug and abandon the well. At the same time, a sidetrack core must be cut in the Pleasant Bayou well and then plugged and abandoned. The total cost of these tests will be several million dollars. The next best testing procedure that will provide a large scientific payback is to cut sidetrack cores and then plug and abandon both the Gladys McCall and Pleasant Bayou wells at a cost of about $1.1 million. The last testing procedure, which will also provide a large scientific payback, is to cut a sidetrack core and plug and abandon Pleasant Bayou, and then plug and abandon Gladys McCall at a cost of about$600,000.Bureau of Economic Geolog

Learning masculinities in a Japanese high school rugby club

This paper draws on research conducted on a Tokyo high school rugby club to explore diversity in the masculinities formed through membership in the club. Based on the premise that particular forms of masculinity are expressed and learnt through ways of playing (game style) and the attendant regimes of training, it examines the expression and learning of masculinities at three analytic levels. It identifies a hegemonic, culture-specific form of masculinity operating in Japanese high school rugby, a class-influenced variation of it at the institutional level of the school and, by further tightening its analytic focus, further variation at an individual level. In doing so this paper highlights the ways in which diversity in the masculinities constructed through contact sports can be obfuscated by a reductionist view of there being only one, universal hegemonic patterns of masculinity

Consolidation of Geologic Studies of Geopressured-Geothermal Resources in Texas

Hydrochemical data obtained from samples of brine produced from the Gladys McCall Zone 8 sandstone reservoir were used to estimate the importance of shale dewatering as a contribution to ultimate reservoir volume. Changes in chloride concentration of produced brines with time were generally small and close to analytical margins of error, but some correlation between production-related pressure drawdown and declining chlorinity was detected. More rigorous analysis of brine composition and source was hindered by nonstandardized sampling and analytical procedures. Geologic data suggest that sandstone interconnection is a more important source of extra reservoir volume than is shale dewatering at the Gladys McCall site. Methods for more definitively determining the effects of shale dewatering and reservoir interconnectedness include direct sampling and chemical analysis of shale water, pressure monitoring and fluid sampling in multiple reservoirs in a single well or a well field, and sidetrack drilling and coring. Petrographic analysis was used to document the effects of experimental compaction on core samples from geopressured-geothermal reservoirs. Experimental compaction simulates the increasing effective stress within these reservoirs as fluid pressures decline during production. Inelastic compaction and brittle failure (fracturing) are closely related to sandstone composition. Sandstones that contain abundant ductile rock fragments and clay minerals undergo large compaction-induced porosity reductions and fracture readily at effective stress levels comparable to those generated in the reservoir during high-volume production. Well-indurated, high-quartz sandstones, such as the Gladys McCall Zone 8, are extremely resistant to both inelastic compaction and brittle failure.Bureau of Economic Geolog

Coordination of Geological and Engineering Research in Support of Gulf Coast Co-Production Program

More than 150 gas fields were reviewed, and 25 fields were selected using modified specific selection criteria as outlined by Gregory and others (1983). Further evaluation of these fields is necessary to obtain a new ranking for Gregory's class A, B, and C divisions. A list of the 25 most favorable fields was sent to Eaton Operating Co., who were to approach likely companies to initiate joint ventures in co-production. Four reservoirs containing dispersed gas were examined for their co-production potential. Reservoirs in Port Acres and Ellis fields produce from the Hackberry Member of the Oligocene Frio Formation, and two reservoirs in Esther field produce from the lower Miocene Planulina Zone. Log-pattern and lithofacies maps, together with stratigraphic position, suggest that the reservoirs are in ancient submarine-fan deposits. Dip-elongate, channel-fill sands are characteristic; reservoir sands pinch out along strike. Growth faults, common in the submarine slope setting, form updip and downdip boundaries, producing combination traps. In Ellis field, co-production accounts for 300 Mcf (8.5 x 106 m3) of gas per day. Port Acres field contains the largest remaining reserves, but other technical and economic factors limit co-production there. Recent drilling has extended primary production and delayed co-production in Esther field. The Gas Research Institute requested that further work on the selection and evaluation of potential co-production gas fields be terminated because funds were required for the Port Arthur project.Bureau of Economic Geolog

Learning and interaction in groups with computers: when do ability and gender matter?

In the research reported in this paper, we attempt to identify the background and process factors influencing the effectiveness of groupwork with computers in terms of mathematics learning. The research used a multi-site case study design in six schools and involved eight groups of six mixed-sex, mixed-ability pupils (aged 9-12) undertaking three research tasks – two using Logo and one a database. Our findings suggest that, contrary to other recent research, the pupil characteristics of gender and ability have no direct influence on progress in group tasks with computers. However, status effects – pupils' perceptions of gender and ability – do have an effect on the functioning of the group, which in turn can impede progress for all pupils concerned

Coordination of Geological and Engineering Research in Support of the Gulf Coast Co-Production Program

Complex and heterogeneous Hackberry reservoirs at Port Arthur field were deposited in a submarine canyon/fan setting. Conventional fieldwide hydrocarbon recovery efficiencies are low, but the potential for secondary gas recovery is high. Free gas remains trapped in uncontacted and untapped compartments at reservoir abandonment. The total fieldwide resource amounts to 13.9 Bcf. The probable and possible resource for a single infill well is 6.5 Bcf in four separate stringers. Three optimum brine-disposal sands and the best brine-disposal site were selected in Northeast Hitchcock field based on sand-body complexity, thickness, depth, and brine-disposal capacity. The equilibrium distribution of inorganic species in different combinations in the produced waters at surface and formation temperatures and pH was estimated from chemical analyses. SOLMNEQ computations suggest carbonate scaling may occur in surface equipment of Miocene disposal sandstones unless inhibitors are used. At Northeast Hitchcock field, well-winnowed sandstones of shallow-marine origin compose the major reservoir sands and act as preferential conduits for fluid migration. Dislodged, abundant authigenic kaolinite in these sands can plug pores during production, suggesting a maximum rate of production will need to be determined to avoid reservoir damage.Bureau of Economic Geolog

The breakdown of the municipality as caring platform: lessons for co-design and co-learning in the age of platform capitalism

If municipalities were the caring platforms of the 19-20th century sharing economy, how does care manifest in civic structures of the current period? We consider how platforms - from the local initiatives of communities transforming neighbourhoods, to the city, in the form of the local authority - are involved, trusted and/or relied on in the design of shared services and amenities for the public good. We use contrasting cases of interaction between local government and civil society organisations in Sweden and the UK to explore trends in public service provision. We look at how care can manifest between state and citizens and at the roles that co-design and co-learning play in developing contextually sensitive opportunities for caring platforms. In this way, we seek to learn from platforms in transition about the importance of co-learning in political and structural contexts and make recommendations for the co-design of (digital) platforms to care with and for civil society

Coordination of Geological and Engineering Research in Support of the Gulf Coast Co-Production Program - Final Report

At Northeast Hitchcock field, the presence of the Skolithos assemblage and other structures has supported the interpretation of shallow-marine, tidal, distributary-mouth-bar, and channel depositional environments for most of the major reservoir sandstones. Several shaly horizons exhibit characteristics of interdistributary bays, and the Frio A is capped by a thin sequence of crevasse splays and washover sands that represent the initiation of the transgression that overlapped the Frio in Anahuac times. The high-energy depositional environment of reworked distributary-mouth-bar sandstones is the major control of the high porosity (around 30 percent) and permeability (around 1,000 millidarcies) in Frio A sandstones at Northeast Hitchcock field. Well-winnowed sandstones with high porosities and permeabilities contain abundant authigenic kaolinite and have served as preferential conduits for migrating acid waters and major fluid flow during co-production. Authigenic clay can create fluid production problems due to its delicate structure. Dislodged clay may obstruct pore throats at high production rates, necessitating the determination of a maximum safe rate of fluid production for co-produced wells. Middle and lower Miocene barrier island sands, buried at depths from 3,500 to 6,800 feet in Northeast Hitchcock field, have the potential to receive large volumes of co-produced brines from the Frio 1-A reservoir. These sands exhibit high permeabilities exceeding 2,000 millidarcies, are internally homogeneous, and are laterally extensive in the field area. The 6,150-foot sand (lower Miocene) was chosen for initial brine disposal in the H.D.S. Thompson No. 3 brine-disposal well based on these criteria. The 3,780-foot sand (middle Miocene) is recommended for future up-hole brine disposal in the H.D.S. Thompson No. 3 well because it is shallower, requiring less injection pressure and lower costs for brine disposal.Bureau of Economic Geolog

Consolidation of Geologic Studies of Geopressured-Geothermal Resources in Texas

Two major structural styles are identified in the Wilcox growth-fault trend of the Texas Gulf Coast. The style in central and southeast Texas is characterized by continuous, closely spaced growth faults that have little associated rollover despite moderate expansion of section and that show little flattening of the fault plane with depth. Where the growth-fault trend crosses the Houston Diapir Province, growth faults are localized by preexisting salt pillows; however, the piercement salt domes formed after the main phase of faulting, so the salt tectonics "overprints" the growth faults. In South Texas (south of Live Oak County), a narrow band of growth faults having high expansion and moderate rollover lies over and downdip of a ridge of deformed, overpressured shale and lies updip of a deep Tertiary-filled basin formed by withdrawal of overpressured shale. Significant antithetic faulting is associated with this band of growth faults. Also in South Texas, the lower Wilcox Lobo trend is deformed by highly listric normal faults beneath an unconformity that is probably related to Laramide tectonic activity. Wilcox sandstone reservoirs are predominantly of high-constructive deltaic (distributary-channel and delta-front) origin. This, together with close spacing of faults and characteristically low permeabilities, limits the size of geopressured reservoirs. The largest reservoirs may be in interfault areas or in salt- or shale-withdrawal basins.Bureau of Economic Geolog

Coordination of Geological and Engineering Research in Support of the Gulf Coast Co-Production Program

Shallow-marine sandstones in Northeast Hitchcock field having high porosities and permeabilities contain abundant authigenic kaolinite and have acted as preferential conduits for fluid migration. Authigenic clay creates fluid production problems because of its delicate structure. Dislodged clay will obstruct pore throats at high production rates. A maximum safe rate of fluid production will need to be determined for co-produced wells. Middle and lower Miocene barrier-island sands in Northeast Hitchcock field have the potential for receiving large volumes of co-produced brines. These sands have permeabilities in excess of 2,000 md, are internally homogeneous, and are laterally extensive in the field area. Detailed geologic analyses of two reservoirs in Seeligson field delineate heterogeneous, fluvial sandstones that probably contain isolated, undrained reservoir compartments. Zone 15 can be subdivided into at least four genetic sandstones, and Zone 18-C can be subdivided into two separate sandstones. Two new pool discoveries (Miocene) in Tom O'Connor field developed during growth-fault activity along the Vicksburg Fault Zone. Deposition of these sandstones, as part of an offshore system during initial parasequence deposition, was confined between the Vicksburg Fault Zone and the Tom O'Connor anticlinal crest.Bureau of Economic Geolog