The Suction Side Sample Catcher in Ground Water Quality Sampling     

Richard Armstrong  Frederick R. McLaren 《Ground Water Monitoring & Remediation》1984,4(4):48-53

A suction side sample collector (SSSC) is a contrivance installed hydraulically ahead of the intake port of a pumping device. This paper describes construction and operational details of SSSCs fitted to a submersible pump with packer for use in a 6-inch cased borehole, an air lift pump with packer for use in a 1-inch or 2.5-inch cased borehole, a bladder pump for use in a casing of 2-inch or greater diameter, and a jet pump with packer for use in a 2-inch cased borehole.
Each form of SSSC has been thoroughly tested in ground water quality sampling for volatile organic chemicals. Comparative data for samples collected with the SSSCs and conventional sample collecting gear are presented. The SSSC is demonstrated to be superior to other methods of collecting volatile organic chemical samples owing to its freedom from contamination by the pump delivery line and to its mode of collecting the sample from a position in the well remote from disturbance by the pumping technique.
SSSCs are conveniently decontaminated, easily transported, and can be used to deliver samples to the laboratory while still at formation pressure. The air-lift pumps, described in this paper for use with SSSCs in 1- and 2.5-inch casings, have pumping capacities greater than obtained by other methods that can operate in these small casings. Discharge rates of up to 2 gpm are routinely achieved with the 1-inch model and higher rates are common With the 2.5-inch model. The use of packers with these pumps reduces the time needed to replace the water in the casing with fresh water from the formation.  相似文献   

Multiple Completion Monitor Wells     

Dennis B. Nakamoto  Frederick R. McLaren  Peter J. Phillips 《Ground Water Monitoring & Remediation》1986,6(2):50-55

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CBED and ALCHEMI investigation of local symmetry and Al,Si ordering in K-feldspars     

A. C. McLaren  J. D. Fitz Gerald 《Physics and Chemistry of Minerals》1987,14(3):281-292

CBED (convergent beam electron diffraction) and ALCHEMI (atom location by channelling enhanced microanalysis) have been used to determine the symmetry and Al-order parameter 2t ₁ within homogeneous regions (of the order of 100 nm in diameter) of high sanidine and low microcline. The results are in excellent agreement with those obtained on the same crystals from X-ray measurements of average T-O bond lengths. In view of this agreement, CBED and ALCHEMI were then applied to an orthoclase with a well-developed tweed microstructure. The results indicate that the specimen is partially ordered and that the average symmetry is triclinic. The lattice modulations involve values of γ* in the range 90°<γ*<90.5°, with correspondingly small variations of 2t ₁ about an average value of 0.67.  相似文献   

Dislocation nucleation and multiplication in synthetic quartz: Relevance to water weakening   总被引：1，自引：0，他引：1  

A. C. McLaren  J. D. Fitz Gerald  J. Gerretsen 《Physics and Chemistry of Minerals》1989,16(5):465-482

Recent observations suggest that the water-related defects associated with the so-called water weakening of single crystals of “wet” synthetic quartz are high-pressure clusters of molecular water. The microstructures which evolve in these crystals during both creep and constant strain-rate experiments and by heating alone were observed by TEM and show that the clusters act as highly efficient sources of the glissile dislocations which must be nucleated before plastic flow can be induced. These microstructural observations, together with simple microdynamical concepts based on the Orowan equation, are used to rationalize the creep behaviour and all the main features of the stressstrain curves observed in “wet” synthetic quartz crystals with a wide range of bulk water-contents, without postulating any direct influence of water on dislocation glide. It is proposed, therefore, that the relatively low yield stress of “wet” synthetic quartz is primarily due to the ease with which fresh glissile dislocations are nucleated, rather than to an enhanced glide of hydrolysed dislocations as is generally assumed in most models of water weakening.  相似文献   

Abnormal development of Dentalium due to the Amoco Cadiz oil spill     

A.SJ. Koster  J.A.M. Van Den Biggelaar 《Marine pollution bulletin》1980,11(6):166-169

A comparison was made between the development of Dentalium eggs, spawned by animals, collected before and after the Amoco Cadiz oil spill. Development of eggs from animals collected before the oil spill was significantly better than development of eggs from animals collected after the oil spill. It is suggested that development is affected by oil hydrocarbons, accumulated during oogenesis in the lipidrich phases of the oocytes.  相似文献   

Use of ⁴⁰Ar/³⁹Ar K-feldspar thermochronology in basin thermal history reconstruction: an example from the Big Lake Suite granites, Warburton Basin, South Australia     

Sandra McLaren  W. James Dunlap 《Basin Research》2006,18(2):189-203

The potential use of ⁴⁰Ar/³⁹Ar thermochronologic data from K-feldspars in reconstructing basin thermal history has been evaluated using the example of the Warburton/Cooper/Eromanga Basin, Australia's largest onshore oil- and gas-producing basin. Results from ⁴⁰Ar/³⁹Ar step-heating experiments reveal details of the evolution of the basin system, including the following: (1) the operation of high geothermal gradient regimes during the earliest basin evolution, suggesting that basin formation was active rather than passive; (2) slow cooling from a Permo-Triassic temperature peak of at least 250–300°C; (3) a rise in thermal gradients to contemporary bottom hole temperatures in the last 5–10 Myr; and (4) spatially variable recrystallization events between 100 and 50 Ma and at around 20 Ma. Initial microstructural observations serve as a useful predictor of the quality and nature of the obtainable age information. Data from 'pristine' K-feldspars may constrain the peak temperature conditions experienced in the basin, the basin's early thermal history and also any recent changes in thermal gradient. Contrasting data from texturally modified K-feldspars may constrain times of thermal transients and/or fluid flow, with the preferred interpretation that K-feldspars recrystallize in response to such events. The Warburton/Cooper/Eromanga Basin example suggests that the ⁴⁰Ar/³⁹Ar technique may serve as a useful adjunct to apatite and zircon fission track analysis and conventional organic maturation indices in basin thermal history analysis.  相似文献   

The domain structure of a transitional anorthite; a study by direct lattice-resolution electron microscopy     

A. C. McLaren 《Contributions to Mineralogy and Petrology》1973,41(1):47-52

Direct resolution of lattice planes corresponding to a-, b- and c-reflections in a transitional anorthite has shown that the material consists of domains of body-centered anorthite (I-An) and primitive anorthite (P-An) in approximately equal proportions. The domains of P-An appear lenticular in shape. Their thickness and orientation readily account for the observed streaking of the c- and d-reflections. Adjacent domains of P-An (separated by a domain of I-An) are observed to be either in register or in antiphase relation, the fault vector being the body-centering vector.  相似文献   

Dislocation structure of the deformation lamellae in synthetic quartz; a study by electron and optical microscopy   总被引：1，自引：0，他引：1  

A. C. McLaren  R. G. Turner  J. N. Boland  B. E. Hobbs 《Contributions to Mineralogy and Petrology》1970,29(2):104-115

Single crystals of experimentally deformed synthetic quartz showing optical deformation lamellae were examined by transmission electron microscopy. Dislocations are distributed fairly uniformly throughout the crystal. However, parallel to the trace of the deformation lamellae, which may be irrational, there are walls of tangled dislocations whose characteristics suggest that they are directly associated with the lamellae. The nature and formation of the optical image is discussed in detail.  相似文献   

Heat flow and inferred ground surface temperature history at Tynong North,southeastern Australia     

G. Beardsmore  M. Sandiford  K. Gordon  M. McLean  S. Egan  S. McLaren 《Australian Journal of Earth Sciences》2017,64(6):753-767

Borehole temperature data have the potential to record historical variations in ground and air surface temperature, yet very few reliable, purpose-drilled, boreholes are available to explore such impacts, particularly in the southern hemisphere. The 400-m deep Tynong-1 borehole, approximately 65 km ESE of Melbourne, Australia, was drilled specifically to determine conductive heat flow and provides a unique dataset for evaluating ground surface temperature history in southeastern Australia. Steady-state conductive heat flow of 87 ± 1 mW m^?2 was determined in the deeper borehole sections, with measured temperature profiles clearly demonstrating a progressive divergence of the observed temperature profile from the equilibrium model in the upper ～150 m of the hole. We applied a Bayesian method employing a reverse jump Markov chain Monte Carlo search algorithm to explore the origins of this variation. Our results indicate a 2°C increase in ground surface temperature since 1800, after at least 500 years of relatively stable ground surface temperature. The inversion results are consistent with the trend of surface air temperature recorded in southeast Victoria by historical meteorological data since 1950. The inferred increase in ground surface temperature evident prior to 1950 is likely a cumulative effect of land clearing and a rise in surface air temperature.  相似文献   

Assessing the forecast skill of Arctic sea ice extent in the GloSea4 seasonal prediction system     

K. Andrew Peterson  A. Arribas  H. T. Hewitt  A. B. Keen  D. J. Lea  A. J. McLaren 《Climate Dynamics》2015,44(1-2):147-162

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