The EChO payload instrument – an overview     

Paul Eccleston  Bruce Swinyard  Marcel Tessenyi  Giovanna Tinetti  Ingo Waldmann  Marc Ferlet  Ranah Irshad  Tanya Lim  Kevin Middleton  Tom Bradshaw  Martin Crook  Tom Hunt  Berend Winter  Ian Bryson  Naidu Bezawada  William Taylor  Neil Bowles  Enzo Pascale  Gianluca Morgante  Emanuele Pace  Alberto Adriani  Jean-Michel Reess  Marc Ollivier  Roland Ottensamer  Mirek Rataj  Gonzalo Ramos Zapata  Jan-Rutger Schrader  Avri Selig  Kate Isaak  Martin Linder  Ludovic Puig 《Experimental Astronomy》2015,40(2-3):427-447

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Tectonic history from vitrinite reflectance   总被引：1，自引：0，他引：1  

M. F. Middleton 《Geophysical Journal International》1982,68(1):121-132

Summary. The degree of organic metamorphism of carbonaceous matter is expressed in terms of the reflectance of vitrinite. Vitrinite reflectance is a function of temperature and time. A model relating vitrinite reflectance to temperature and time is proposed from published vitrinite reflectance—temperature—time nomograms. A plot of the logarithm of vitrinite reflectance versus depth gives a linear curve (for vitrinite reflectance greater than 0.3 per cent) in a sedimentary basin which has had a constant geothermal gradient throughout its tectonic history; the geothermal gradient (°C km⁻¹) is equal to the slope of the curve multiplied by 194.8. The model is also applied to sedimentary basins with decreasing geothermal gradient with time (i.e. cooling continental-margin basins). The vitrinite reflectance model is demonstrated to be consistent with observed reflectance data and tectonic information from the Sydney, Bowen-Surat and Gippsland basins in eastern Australia.  相似文献   

Low-temperature demagnetization isolates stable magnetic vector components in magnetite-bearing diabase   总被引：1，自引：0，他引：1  

G. J. Borradaile  K. Lucas  R. S. Middleton 《Geophysical Journal International》2004,157(2):526-536

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Al andBe production in iron meteorites     

D. Aylmer  V. Bonanno  G.F. Herzog  H. Weber  J. Klein  R. Middleton 《Earth and Planetary Science Letters》1988,88(1-2)

We have measured by accelerator mass spectrometry the²⁶Al contents of 20 and the¹⁰Be contents of 14 iron meteorites. The²⁶Al contents are typically 30% or more lower than values obtained by counting techniques; the¹⁰Be contents are 10–15% lower. The production rates (P) of these nuclides decrease by more than a factor of two as the⁴He/²¹Ne ratio increases with increasing shielding from 200 to 400. For the lighter shielding conditions expected in stony meteorites we estimateP₂₆(Fe) as 3–4 dpm/kg andP₁₀(Fe) as 4–5 dpm/kg. The average P/₁₀P₂₆ activity ratio is close to 1.5. Exposure ages calculated from²¹Ne/²⁶Al ratios cannot be calibrated so as to agree with both⁴⁰KK/ ages and ages based on the shorter-lived nuclides³⁹Ar and³⁶Cl. If agreement with the latter is forced, then the disagreement with⁴⁰KK/ ages may signal a 35% increase in the cosmic-ray intensity during the last 10⁷ a.  相似文献   

Anomalous isotopic concentrations in the sea off Southern California     

Louis Brown  Jeffrey Klein  Roy Middleton 《Geochimica et cosmochimica acta》1985,49(1):153-157

Measurements are reported of the ¹⁰Be concentrations in 15 sediments from the sea off southern California. The sedimentation patterns are modelled with a two component system, one component having the high ¹⁰Be concentration of pelagic sediment and the other the low concentration of continental runoff. The pelagic component, brought to the region by the California Current with the Pacific Ocean as reservoir, is very likely the source not only of anomalously high ¹⁰Be deposition but also of similar effects with ²¹⁰¹Pb, ^239,240pu and ²⁴¹Pu.  相似文献   

¹⁰Be accumulation in a soil chronosequence     

Milan J. Pavich  Louis Brown  Jeffrey Klein  Roy Middleton 《Earth and Planetary Science Letters》1984,68(2):198-204

We have measured the concentration of the cosmogenic isotope¹⁰Be in soil samples from various horizons at six sites, including three independently dated Rappahannock River terraces and a previously undated Piedmont soil to which we have assigned an age. All of the incident¹⁰Be can be accounted for in one of these soils and a second is within a factor of two. In three soils, whose concentrations vary widely with depth, a significant fraction of the incident¹⁰Be cannot be accounted for. Incomplete sampling, and enhanced Be mobility caused by organic components, are the probable reasons for the low inventory of Be from these three soils. Overall, the data from these six sites indicate that¹⁰Be accumulation could be used to assign ages to soils if Be is not mobilized and lost from the soil profile.  相似文献   

Extinct mountain goat (Oreamnos harringtoni) in Southeastern Utah     

Jim I. Mead  Larry D. Agenbroad  Arthur M. Phillips  III  Larry T. Middleton 《Quaternary Research》1987,27(3)

The extinct Harrington's mountain goat (Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce (Picea engelmannii), limber pine (Pinus flexilis), rose (Rosa cf. woodsii), and Douglas fir (Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper (Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch (Betula) is determined from pollen clumps in dung pellets.  相似文献   

The humber observatory: Concepts,instrumentation and software systems     

J. Hardisty  H. L. Rouse  R. Middleton  R. S. Hirst  T. Scott 《地球表面变化过程与地形》1995,20(9):859-880

The role of geomorphological research into sediment flux within modern dynamical systems and the consequent role of geomorphological research in the development of practical environmental management tools are seldom reconciled. Sediment fluxes can be estimated using instruments and numerical models, but problems arise when these results are to be interpreted to inform the environmental management debate. This paper presents one set of solutions in which we describe the work of the Humber Observatory and detail the concepts, instrumentation and software systems which have been developed to address such issues. The design and deployment of a new, automated meteorological station, new multiple sensor, radio-linked outstations and the collection of associated tidal and bathymetric data are described, together with discussion of the operational problems and data archiving and output issues. We also describe the numerical models based upon the dynamical equations which have been used to estimate water and sediment fluxes through the Humber Estuary, and we describe the design criteria for new semi-empirical models. Results from the various systems and models are presented as the basis for a regional research capability and in terms of operational delivery for environmental management.  相似文献   

Relative abundance of snapper (Chrysophrys auratus) across habitats within an estuarine system     

DM Parsons  D Buckthought  C Middleton  G MacKay 《新西兰海洋与淡水研究杂志》2016,50(3):358-370

Many fish species rely on estuarine nursery habitats as they transition to adult life stages. Quantifying nursery value, however, requires identification of the life stages (often small and short-lived) that utilise nursery habitats, and survey methods that provide comparable estimates across habitats. We focused our surveys on post-settlement snapper (Chrysophrys auratus) using video camera deployments across habitats within a northeastern New Zealand harbour. Post-settlement snapper abundance was higher among structured habitat types relative to bare sediments, with the type of structured habitat not influential. The exception appeared to be for reef habitat (although sampling was limited). Reef sites were structurally complex, but largely inhabited by older life stages (snapper and other fish species). Overall, nursery value for snapper appears to be connected to structure, rather than structure type. This result emphasises the importance of a broadened scope to coastal fishery management, one that incorporates not just fish extraction, but also habitat maintenance or restoration.  相似文献   

Channel Modeling and Threshold Signal Processing in Underwater Acoustics: An Analytical Overview   总被引：1，自引：0，他引：1  

Middleton  D. 《Oceanic Engineering, IEEE Journal of》1987,12(1):4-28

An overview of underwater acoustic channel modeling and threshold signal processing is presented, which emphasizes the inhomogeneous, random, and non-Ganssian nature of the generalized channel, combined with appropriate weak-signal detection and estimation. Principal attention is given to the formal structuring of the scattered and ambient acoustic noise fields, as well as that of the desired signal, including both fading and Doppler "smear" phenomena. The role of general receiving arrays is noted, as well as their impact on spatial and temporal signal processing and beam forming, as indicated by various performance measures in detection and estimation. The emphasis here is on limiting optimum threshold systems, with some attention to suboptimum cases. Specific first-order probability density functions (pdf's) for the non-Ganssian components of typical underwater acoustic noise environments are included along with their field covariances. Several examples incorporating these pdf's are given, to illustrate the applications and general methods involved. The fundamental role of the detector structure in determining the associated optimum estimators is noted: the estimators arc specific linear or nonlinear functionals of the original optimum detector algorithm, depending on the criterion (i.e., minimization of the chosen error or cost function) selected. Results for both coherent and incoherent modes of reception are presented, reflecting the fact that frequently signal epoch is not known initially at the receiver. To supplement the general discussion, a selected list of references is included, to provide direct access to specific detailed problems, techniques, and results, for which the present paper is only a guide.  相似文献