This study was conducted for palynological investigation of recent deposits from east Isfahan in order to reconstruct past environmental conditions of this region. Segzi area is located in 30 km east Isfahan and Rangideh area is 65 km in south east Isfahan. In these areas it was seen, in depth of soil profile, dark layers containing organic matters. Soil samples were taken from five points and ...

Beneath the Pacific Northwest the Juan de Fuca plate, a remnant of the Farallon plate, continues subducting beneath the North American continent. To the east of the Cascadia subduction zone lies the Yellowstone Hotspot Track. The origins of this track can be traced back to the voluminous basaltic outpourings in theColumbia Plateau around 17Ma. If these basalts are the result of a largemelting a...

Cross-spectral techniques are used to analyze the relationship between gravity and bathymetry at the Mid-Atlantic Ridge and the East Pacific Rise crests. The resulting transfer functions were used to study the nature of the isostatic mechanism operative at these ridge crests. The most satisfactory results were obtained for models in which the oceanic lithosphere is treated as a thin elastic pla...

S U M M A R Y Rayleigh wave group velocity dispersion measurements from local and regional earthquakes are used to interpret the lithospheric structure in the Gulf of California region. We compute group velocity maps for Rayleigh waves from 10 to 150 s using earthquakes recorded by broadband stations of the Network of Autonomously Recording Seismographs in Baja California and Mexico mainland, U...

High resolution images obtained with the Arecibo radar system at a wavelength of 12.6 centimeters reveal numerous parallel 10to 20-kilometer-wide bands of high radar backscatter situated on and oriented parallel to the major mountain ranges of the Ishtar Terra region of Venus. Geometric and morphological characteristics suggest that the bands represent Earth-like tectonic deformational features...

Land degradation is one of the major environmental problems worldwide and has become particularly severe in recent decades in China, with its rapid economic developments. China has an enormous area of grasslands, covering 41% of its territory (3.93 million km), and grasslands are regarded as among the most important natural resources because of their ecological and economic importance. However,...

CASE SHOWING THE CONTAGIOUSNESS OF PHTHISIS. A man of thirty-four had been sick with phthisis about four years; gradually grew from bad to worse, until the usual end was reached. It was not until the last three or four months of his life that he was confined to his bed. He was fond of pets, and during these three or four mouths, it was hia fancy to have his dog in the room nearly all the time. ...

Waveguides with low confinement loss, low chromatic dispersion, and low nonlinear effects are used in optical communication systems. Optical fibers can also be employed in such systems. Besides optical fibers, photonic crystal fibers are also highly suitable transmission media for optical communication systems. In this paper, we introduce two new designs of index-guiding photonic crystal fiber ...

We use P and S arrival times from 5225 earthquakes and 53 explosions, recorded by the Southern California Seismographic Network, to invert for the three-dimensional Pvelocity (Vp) and the P and S-velocity ratio (Vp/Vs) in the central Transverse Ranges and the Los Angeles basin. To model longwavelength features of the velocity structure, we invert for the models by interpolating models determine...