Electron microscopic investigations of sand material in the coredrillings in the Great Hungarian Plain in Loess (INQUA).
The study informs about the electron microscopic investigation of the sand layers in seven coredrillings in the Danube-Tisza interfluve region. In five out of six drillings on the alluvial fan of the Danube blown sand layers were explored
. There were apparently phases in the formation of the alluvial fan when on certain parts flooding was replaced by eolian processes. The seventh drilling (at Janoshalma) proves that this region constitutes the continuation of Transdanubia and does not belong
A portable earth-drill system for permafrost studies
Canada ; Cold area ; Core sampling ; Ice ; Periglacial features ; Permafrost ; Quebec ; Research technique ; Soil
This technique note presents a light drill specially designed for coring in permafrost. The drill was improved over several years at Université Laval's Centre d'études nordiques. This equipment allows total-length recovery of cores 10 cm in diameter
nearly without alteration, and works in most kinds of frozen soils. Drilling is possible to 7 m using a two to three-person operating crew.
Zur tektonischen Bearbeitung von Bohrkernen. (Tectonical treatment of drillcores)
Methodological references are given concerning the collection, documentation and evaluation of structural tectonic elements of cores. This is followed by the discussion of the most important results of investigation which are not only of regional
Marine drilling exploration. Technical and environmental criteria for rig selection
Four categories of drilling and sampling application are discussed: (1) engineering-geological investigations to assess the foundation conditions for large offshore structures, (2) mineral exploration to determine the economic value of potential
mining deposits, (3) geological mapping of the ocean floor and (4) petroleum exploration. Within these four major areas, variables are considered that influence the rationale for selection of a particular rig. Selection criteria include sampling, coring
and dynamic testing capability, limiting target drilling depths, operating-basis environmental conditions, necessary support vessels and personnel.
A janoshalmi MAFI alapfuras homoküledékeinek elektronmikroszkopos vizsgalata. (Electron microscopic investigation of the sand sediments in the coredrilling of MAFI-Hungarian State Geological Institute-at Janoshalma)
The object of this study is a 3029 m long deep ice coredrilled in 1990-1992 by the European Greenland Ice-Core Project (GRIP). This core reaches nearly to bedrock and reaches back to 250,000 yr B.P., according to dating based partly
on stratigraphic methods and partly on ice-flow modeling. Discussion of the climatic fluctuations suggested by the Eemian deposits in the GRIP core.
This article contains results from the analysis of a core of 25 m length, drilled in the distal part of the sandur. The stratigraphy of the core is described in general terms with information on bedding, grain size distributions, etc. The content
of diatoms has been analysed, showing that the sediments of the lower part of the core were deposited in a marine environment. The petrographic composition of the core sediments has also been investigated. The sediments are rich in volcanic glass, the origin
Annual mass-balance series of a temperate glacier in the Caucasus, reconstructed from an ice core
Caucasus ; European part of Russia ; Geochemistry ; Geophysics ; Glacier ; Glacier mass balance ; Ice core ; Oxygen 18 ; Time series ; Twentieth Century
Identification of annual layers in a firn/ice core provides a possibility to reconstruct the mass-balance sequence for glaciers where no direct observations have been carried out. A number of cores is obtained from the boreholes drilled
In order to establish the environmental conditions during the late Pleistocene and Holocene, four cores were drilled in the west-central sector of Chalco Lake. Variations in the magnetic susceptibility, pollen, diatoms, and loss-on-ignition
in the upper 8m in two close, parallel cores have been studied in order to evaluate erosion, paleoclimate, vegetation, and lake-level changes.
Ostracod assemblages and their environmental significance from the lake core of the Nam Co on the Tibetan Plateau 8.4 kaBP
A long lacustrine core was drilled in the Nam Co in the central-southern part of the Tibetan Plateau. From the core, 15 species of ostracods (Crustacea: Ostracoda), which belong to 6 genera have been identified. According to the variations
On overlapping sections and drillcores of an autochthonous paleosoil and the saprolite underneath, the morphological, geochemical and mineralogical zonation of a complete profile of the weathering mantle has been reconstructed. The data indicate
; Cenozoic paleoceanography ; Mesozoic paleoceanography ; Evolution of polar marine biota ; Age and nature of major structural units ; Strategy for Arctic deep-sea drilling from the scientific point of view ; Possible approaches towards the ultimate goal
This paper reports the chronology as established by the uranium-series dating on a coredrilled from Badwater Basin in Death Valley. To assess the source of uranium in these lacustrine deposits, the AA. have also analyzed uranium and its isotopic
Seismic and drill-core surveys showed that the quartz sandstone superposes an unconsolidated, mechanically produced Upper Proterozoic weathering crust. Excavations and sedimentological analyses revealed that the local tors developed in coarse
To study the climatic history of the Quaternary of Colombia, a drill-core of 357 m depth has been analyzed. For the time being it seems that this sequence of over 3.5 millions years is the longest continuous climatic record of the world, at least
The study of a core, drilled near the town of Loudun (Vienne) has allowed the authors to follow the variations of micropaleontological association (Foraminifera, Ostracoda, Palynology) all along the Cenomanian succession of the South-West part
Chemical erosion ; Core sampling ; Erosion rate ; Experimental catchment ; Fracture ; Puerto Rico ; Regolith ; Underground water ; Water budget ; Watershed ; Weathering
aboveground and along fracture surfaces on subsurface rocks. Such corestones at the land surface are assumed to be what remains after exhumation of similar, fractured bedrock pieces that were observed in the drilledcores between thick layers of regolith. Some
of these subsurface corestones are massive and others are highly fractured, whereas aboveground corestones are generally massive with little to no apparent fracturing. Subsurface corestones are larger and less fractured in the borehole drilled on a road where
it crosses a ridge compared with the borehole drilled where the road crosses the stream channel. Both borehole profiles indicate that the weathering zone extends to well below the stream channel in this upland catchment; hence weathering depth