Chronology of late wisconsinan glaciation in middle North America     

Lee Clayton  Stephen R. Moran 《Quaternary Science Reviews》1982,1(1):55-82

We propose a chronology of late Wisconsinan glacial fluctuations in middle North America, from Alberta to Wisconsin, based on radiocarbon dates derived solely from wood. Previous chronologies of the southwestern margin of the North American Continental Ice Sheet have depended to a considerable degree on radiocarbon dates from fine-grained organic sediment. This material is commonly contaminated with older carbon, resulting in chronologic confusion. By using only dates from wood, much of the confusion disappears. However, because of the scarcity of wood dates, only four of the sixteen identified fluctuations are accurately dated: an advance into Iowa about 14,000 to 13,500 BP, an advance into South Dakota and Iowa about 12,300 BP, an advance into the Lake Michigan basin about 11,700 BP, and an advance into the Lake Superior basin about 9900 BP. In addition, the beginning of late Wisconsinan glaciation, before 20,000 BP, is fairly well documented. None of the fluctuations in the western part of the region are accurately dated.  相似文献   

Interplanetary scintillation observations of interaction regions in the solar wind     

A. R. Breen  P. J. Moran  C. A. Varley  W. P. Wilkinson  P. J. S. Williams  W. A. Coles  A. Lecinski  J. Markkanen 《Annales Geophysicae》1998,16(10):1265-1282

Co-rotating interaction regions (CIRs) between fast and slow streams of plasma are a prominent feature of the solar wind. Measurements of interplanetary scintillation (IPS) using the three widely separated antennas of the EISCAT facility have been used to detect the compression regions at the leading edges of interaction regions and to determine the location and velocity of the structure. Observations show that interaction regions have developed as close to the Sun as 25–30 solar radii, a result supported by theoretical modelling which shows that the conditions needed for CIRs to develop exist inside 30 solar radii.  相似文献   

Measurements of the direction of the solar wind using interplanetary scintillation     

P. J. Moran  A. R. Breen  C. A. Varley  P. J. S. Williams  W. P. Wilkinson  J. Markkanen 《Annales Geophysicae》1998,16(10):1259-1264

EISCAT observations of the interplanetary scintillation of a single source were made over an extended period of time, during which the orientation of the baselines between the two observing sites changed significantly. Assuming that maximum correlation between the scintillations observed at the two sites occurs when the projected baseline is parallel to the direction of plasma flow, this technique can be used to make a unique determination of the direction of the solar wind. In the past it has usually been assumed that the plasma flow is radial, but measurements of eleven sources using this technique have indicated conclusively that in at least six cases observed at mid or high heliocentric latitude there is a significant non-radial component directed in four cases towards the heliocentric equator and in two cases towards the pole.  相似文献   

The malic enzyme MEP-2* locus in Spanish populations of Atlantic salmon: Sea age and foreign stocking     

Paloma Moran  Juliana Perez  Eva Garcia-Vazquez 《Aquatic Sciences - Research Across Boundaries》1998,60(4):359-366

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A Note on Extension Variances in IR2     

Chadœuf  Joël  Moran  Chris  Goulard  Michel 《Mathematical Geosciences》1998,30(6):575-587

Matheron (1971) proposed an approximation of the extension variance in IR. We propose in this note an extension of this formula in IR ² , based on a MacLaurin formula. Its application is shown in an example, the estimation of the maximum depressional storage of a soil surface.  相似文献   

SURVEY OF 31 GROUND-WATER CONSULTANTS ON HOW TO PLAN FOR A CAREER IN HYDROGEOLOGY     

Michael J. Moran 《Ground water》1986,24(6):818-819

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The Sub-Pc Scale Accretion Disk of Ngc 4258     

E. M. L. Humphreys  A. L. Argon  L. J. Greenhill  M. J. Reid  J. M. Moran 《Astrophysics and Space Science》2005,295(1-2):285-289

Water megamasers have been found to trace parsec/sub-parsec, circumnuclear accretion disks in several AGN (e.g., Circinus, NGC 1068 & NGC 4258). High-spatial (0.5 mas) and velocity resolution (0.2 km s^–1) VLBA imaging of the disks reveals thin, warped pannekoeken (pancake)-style structures as opposed to thick tori in the inner regions of the central engines (40 000 R_sch). In this contribution, I will describe some current investigations into the dynamical and physical attributes of the water maser disk in NGC 4258, as revealed by VLBA, VLA and Effelsberg monitoring over 8 years.  相似文献   

Ground water availability: the challenge ahead in water-scarce regions     

Moran MJ 《Ground water》2004,42(4):480-480

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LoCuSS: luminous infrared galaxies in the merging cluster Abell 1758 at z= 0.28     

C. P. Haines  G. P. Smith  E. Egami  N. Okabe  M. Takada  R. S. Ellis  S. M. Moran  K. Umetsu 《Monthly notices of the Royal Astronomical Society》2009,396(3):1297-1307

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EISCAT measurements of the solar wind     

A. R. Breen  W. A. Coles  R. R. Grail  M. T. Klinglesmith  J. Markkanen  P. J. Moran  B. Tegid  P. J. S. Williams 《Annales Geophysicae》1997,14(12):1235-1245

EISCAT observations of interplanetary scintillation have been used to measure the velocity of the solar wind at distances between 15 and 130R (solar radii) from the Sun. The results show that the solar wind consists of two distinct components, a fast stream with a velocity of 800 km s^–1 and a slow stream at 400 kms^–1. The fast stream appears to reach its final velocity much closer to the Sun than expected. The results presented here suggest that this is also true for the slow solar wind. Away from interaction regions the flow vector of the solar wind is purely radial to the Sun. Observations have been made of fast wind/slow wind interactions which show enhanced levels of scintillation in compression regions.  相似文献