Real time evaluation of shear wave velocity during the seismic cone penetration test

170A principles of high resolution shallow seismic reflection surveying are outlined and problems peculiar to this technique at depths less than 200m are discussed. Site requirements for shallow seismic reflection to be economic are examined. 933242 Short-pulse radar detection of groundwater in the Sagavanirktok River floodplain in early spring Arcone, S A; Chacbo, E F; Delaney, A J Water Resonr Res V28, N11, Nov 1992, P2923-2936 Short pulse U H F radar has been used to search for unfrozen water beneath ice blisters and within the gravel of an Alaskan floodplain. The flat snow-covered surface allowed good antenna-ground coupling, and low-loss propagation in the ice and gravel allowed structural details to be revealed. Unfrozen water was inferred from strength and polarization of the reflected waves. A number of zones of unfrozen water (taliks) were located in the upper 7m. 933243 Real time evaluation of shear wave velocity during the setuni¢ cone penetration test Piccoli, S; Smits, F P Proc 3rd Imernatiomd Symposium on Field Meamremems im Geomeclmsics, Oslo, 9-11 September 1991 V1, P159-166. Publ Rotterdam." A A Balkema, 1991 A method is presented which uses a seismic cone penetrometer with two geopbones mounted behind the conventional piezocone tip. The S wave velocity is calculated using the true interval method on waveforms received from the geophones in response to one source wave sent from the ground surface. Interval travel times are interpreted in the time domain using the cross correlation function. This results in significantly less scatter than the visual method for determining interval travel time, particularly at large depths. However, damping effects make the cross correlation interval travel time dependent on length of the received wave train, and improvements in the interpretation method are desirable. 933244 Application of ultrasound measurement technique in the observation of underground surrounding reck stability Sun, Y; Lu, S; Zhou, C Proc Conference on Froct~'ed and JoiMed Rack Masses, Lake Tahoe, 3-5 June 1992 P219-224. Publ California: Lawrence Berkeley Laboratory, 1992 A borehole ultrasonic probe with dry coupling has been developed to investigate rock mass properties. Because of direct contact between the transducer and the borehole wall, effects of wave reflection or refraction found with water-coupled or capsule-coupled probes are eliminated. Design and laboratory characterisation of the instrument are described. It has been applied to map acoustic wave velocity, and hence the state of the rock mass, around a coal mine roadway.

described. The load ceil which measures the compressive stress wave beneath the SPT anvil consists of an 0.5m length of strain-gauged AW rod. The force-time record of each hammer blow is captured by special software and processed on a PC. Examples of use and results of this system are presented and discussed. 933246

Bulk Samldlag of coarse ~

sediments for purfle~-size

analysis. Short commeakatlon Gale, S J, Hoare, P G Earth Surf Process Land VI7, N7, Nov 1992, P729-733 A major problem when sampling coarse sediments for particle size analysis is to ensure the sample mass is sufficient to obtain a representative sample of each size fraction found in the deposit. The actual size distributions have been examined for a wide range of elastic deposits, and based on this work, a guide is presented for sample size to obtain reproducible measures of particle size distribution for tills, fluvial gravels, and beach gravels. 933247 Quick, inexpensive, self-contained sedimmt coring system for use underwater Jones, B; Phimester, K F; Hunter, I G; Blanchon, P J Sedimem Petrol V62, N4, July 1992, P725-728 An inexpensive coring system, independent of surface support, for application in shallow water depth (less than 30m) or at the surface is described. It is based on an air chisel with a coring head, driven by a SCUBA tank, and can force a l m long core tube into sediments in less than 1 minute. The coring head design is shown. Operation is described and a cross section of recovered core illustrated. 933248 Devonian gas technology - 1. New tools and methods improve preduction petenflni Blauch, M E; Venditto, J J, McMechan, D E; Smith, R K; Hyde, P V; Harris, P A Oil Gas $ VgO, N40, Oct 1992, P70-76 A long term plan is underway to optimise gas production from the Devonian shales of the Appalachian and adjacent basins. The shales show strong depositional fabric, low porosity, and permeability anisotropy. There are large gas reserves in abundant thick, organic rock layers. Open hole well logging, core analysis and CT scanning, and stress regime determination have been carried out to characterise the geological environment. Hydraulic fracture stimulation treatments and fluids are being developed. 933249

Borehole and core logging See also: 933072, 933077, 933150, 933214, 933294 933245

Standurd lassetrae~ test meqly measnremmts eaing a syatem baaed on the personal computer Robertson, P K; Woeller, D J; Addo, K O Can Geoteeh J V29, N4, Aug 1992, P551-557 In situations where comparison of SPT results is important, the efficiency of the equipment in terms of energy transfer must be evaluated. A new SPT energy calibration system is

Computer-nided matching of plane core structures with

borehole memmremeute for core orientation Kessels, W; Kuck, J Sei D r i i l ~ V3, NS, 1992, P225-238 A method is presented which facilitates matching of plane structures of a core section and the sinusoidul image of the borehole wall obtained with the Formation Microscanner or Borehole Televiewer. Dip, azimuth, and depth of individual structures are matched using the computer program CREOS, which passes the core image at selected intervals through all possible positions in a predefined search range of the borehole image. Improved accuracy of matching and time saving are obtained.

© 1993 Pergamon Press Ltd. Reproduction not permitted