853359 Sampling and bulking strategies for estimating soil properties in small regions Webster, R, Burgess, T M J Soil Sci V35, N1, March 1984, P127-140

Optimal rectangular grid samphng configurations gwmg mmi- mlzed estimation varmtlons are described using geostatlstlcal methods For hnear seml-vanograms, square blocks are best estimated by sampling at the nodes of a centrally placed grid of interval equal to block size dwlded by square root of sample size The same configuration is nearly optimal for spherical seml-vanograms Bulking of samples wdl mcrease the precision for properties that can be measured on a disturbed sample Usmg the geostatlStlCal approach, true variances can be less than those apparent w~th classical theory, and the samphng ef- fort consequently less

853360 Improved sampling in coarse-grained soils (In Norwegian) Johannessen, I, Kolstad, P Norw Geotech lust Publ N150, 1984, P1

A solution has been reached, which solves some problems relating to deep sampling in sods contalnmg sand, gravel, stones or boulders, by systemizmg the experience from sampling, bormg technique and eqmpment

853361 Developments in drillhole logging Archer, J S, Taylor, F Royal School Mines J N341988, 1984

Techniques and eqmpment, currently available and under development, for dnllhole loggmg are surveyed Conng and core analysis and the various methods of obtaming and inter- preting information from open hole well logging are considered Particular emphasis ~s given to the new developments of the Repeat Formation Tester (RFT) tool and the development of Measurement While Drdhng (MWD) devices The history, development economics, and state-of-the-art technology of MWD systems under development, and the companies in- volved, is detailed

Photographic techniques

See a~o 853273

853362 Role of photo-interpretatmn and landsat image analysis for geotechnical studies-with examples Roy, A K, Bhattacharya, A In: Engineering Geoseiences, edited by B B S Singhal P9-19 Publ Meerut, India Sarzta Prakashan, 1982

LANDSAT was used to survey several sites in India Remote surveying can provide geotechnlcal reformation and demons- trate accesslblhty of deposits, but the quahty of a deposit can only be determined by closer inspection

853363 Tectonic framework and structural evolution of parts of Dec- can Trap province of Western Maharnshtra, India: a study based on remote sensing techniques Powar, K B. Patti, D N In: Engineering Geosciences, edited by B B S Singhal P20-33 Publ Meerut. India Sarlta Prakashan. 1982

LANDSAT and aerial photography were used to survey the Maharashta region Major fault zones were exposed and at- tempts made to correlate the data with previous work in this area

106A

Geophys ica l techniques

See a~o 853161

853364 Appraisal of the problem of direct hydrocarbon detection b~ seismic method Upadhyay, S K In: Engineering Geoscwnces, edited by B B S Singhai P215- 226 Publ Meerut, India Sartta Prakashan 1982

The use of seismic examination as a low cost alternative to cur- rent procedures for oil detection is surveyed It is necessar) for further theoretical and statistical analysis to be carried out. in- cluding realistic situations, before the method can accurately detect liquids

853365 New algorithm for detecting reflection coefficients in layered media Arsene, G, Ceausescu. Z, Potra, F A, Timotln, D Annales Geophysicae VI. N4-5 July-Oct 1983 P285-290

Problems in obtaining reflection coefficients of layered struc- tures from the unit response were studied using an equwalent problem from the theory of linear operators in HIlbert spaces The resulting algorithm, which used the last term of the unit response and all other computed reflection coefficients, gave a reflection coefficient which seems to be fitted for controlling noise and for deep detection Preliminary results using real and synthetic data are described

853366 Microseismic monitoring at Faiconbridge Mine, Falconbridge, Ontario Davldge, G R CIM Bull V77, N868, Aug 1984, P45-49

The mlcroseismlc monitoring system described is situated in a shaft room, 1200m deep and 25m from the ore zone in an area dissected by several faults The system is interfaced with a microcomputer and performs routine data evaluation The pro- grams used are described and selected results are presented

853367 Significance of magnetic susceptibility measurements from the Lac du Bonnet batholith, Manitoba, Canada La Pomte, P, Chomyn, B A, Morms, W A, Coles. R L Geoexploratian II22, N3-4, July 1984, ['217-229

Work undertaken at the Lac du Bonnet bathohth, Manitoba, Canada, revolved examining borehole cores using magnetic methods, measunng the magnetic susceptibility and its anlsotropy and the magnetic remanence The variation of these properties was used to estimate the geological properties of the rock Magnetic susceptlbihty has to date proved the most suc- cessful technique Different magnetic zones can be identified which indicate presence of fractured rock, degree of rock altera- tion and hthologlcal variations

853368 Crosshole audiofrequency seismology in granitic rocks using piezoelectric transducers as sources and detectors Wong, J, Hurley, P, West. G F Geoexploration V22, N3-4. July 1984, P261-279

A high resolution borehole to borehole seismic system has been developed and evaluated Promising preliminary results indi- cate the range to be 100-140m in weathered, jointed or fractured Precambrian rock High signal to noise ratios have been ac- hieved and existing equipment may have a range up to 300m, with range of 1 km being attainable wlth a more powerful trans-