The U.S. Geological Survey, in cooperation with San Antonio Water System, conducted a geophysical and geological study of the Cibolo Canyon development area, northeast Bexar County, Texas, to characterize hydrostratigraphic features and to map surface and subsurface hydrogeologic features of the Edwards aquifer. Capacitively-coupled (CC) resistivity and frequency-domain electromagnetic (FDEM) p...

Travertine deposits are a kind of continental carbonates that form in specific chemical, physical and biological conditions. Garab travertines in southeast of Mashhad are studied based on field, geochemistry (elemental and stable isotope analysis) and hydro-geochemistry analysis. Field and petrographic characterization led to recognize of crystalline crust, raft, foam, shrub, laminated, black m...

It is suggested that homotaxial biostratigraphic units are an unsuitable basis for the definition of a New Zealand Tertiary geological time scale. Three other possible ways of setting up a time scale are discussed, and it is concluded that stratigraphic marker pegs offer the best basis for a rigorously defined time scale. In order to avoid the disadvantages of a hierarchical system of naming it...

The geothermal resources in sedimentary basin are affected by many factors because the characteristic of geothermal reservoirs is very complex, so the heat storage capacities are hard to calculate. This paper took Dunhuang Basin as an example to analyze the geological structure, stratigraphic structure and the formation mechanism of geothermal water based on the formation characteristics of the...

We use multichannel seismic reflection profiles to determine the seismic stratigraphy of the flexural moat that flanks the Canary Islands. The moat stratigraphy has been divided into 5 units on the basis of internal character and correlation of distinctive reflections. The deepest units, I and II, which well-ties indicate are Eocene and older, thicken towards the east suggesting they are the co...

Geological mapping of the area around Baltis Vallis, the longest (6,800 km) canali-type channel on Venus, has led to the determination of stratigraphic relations which appear to be consistent over this entire region comprising -20 x 106 km 2 or -5% of the total surface of Venus. The most abundant unit in the study area, plains with wrinkle ridges (Pwr), consists of two subunits separated by the...

the permian deposits in the stratigraphic section of sangsar (located in the eastern alborz), are the best expose in the semnan area. this sequence consists of the doroud (asselian-sakmarian), ruteh (artinskian-murgabian) and nessen (early djulfian) formations. the dorud formation in the studied section with 56 m thickness consists of conglomerate, sandstone and quartzite, which is disconformit...