Ground Penetrating Abilities of a New Coherent Radio Wave And

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TECHNICAL paper Ground penetrating abilities of a new coherent radio wave and microwave imaging spectrometer G C Stove, M J Robinson, G D C Stove, and A Odell, Adrock; J McManus, Department of Earth Sciences, University of St Andrews

he early use of synthetic aperture each subsurface rock layer. The aim transmitted ADR beams typically pulsed electromagnetic radio radar (SAR) and light detection of this article is to report on tests operate within the frequency range waves, microwaves, millimetric, or Tand ranging (Lidar) systems from of the subsurface Earth penetration of 1-100MHz (Stove 2005). sub-millimetric radio waves from aircraft and space shuttles revealed capabilities of a new spectrometer In recent years, the technology materials which permit the applied the ability of the signals to penetrate as well as its ability to recognize for the production of laser light energy to pass through the material. the ground surface. Atomic dielectric many sedimentary, igneous and has become widely available, and The resonant energy response resonance (ADR) technology was metamorphic rock types in real- applications of this medium to can be measured in terms of energy, developed as an improvement over world conditions. the examination of materials are frequency, and phase relationships. SAR and ground penetrating radar Although GPRs are now constantly expanding. Although the The precision with which the (GPR) to achieve deeper penetration popular as non-destructive testing earlier applications concentrated process can be measured helps of the Earth’s subsurface through the tools, their analytical capabilities on the use of visible laser light, define the unique interactive atomic creation and use of a novel type of are rather restricted and imaging the development of systems using or molecular response behaviour of coherent beam. is often crude. The relatively invisible laser light are now being any specific material, according to When pulsed electromagnetic high transmitter power used in further explored. the energy bandwidth used. ADR radio waves pass through a material, conventional GPRs gives only Maser beams are well known. is measurable on a very wide range they generate measurable responses very shallow penetration in many They are coherent beams of of hierarchical scales both in time in terms of energy, frequency, and soils and rocks. Conventional electromagnetic waves at microwave and space. Time scales may range phase relationships. A deployment SAR systems, which also use and radio wave frequencies. They from seconds to femtoseconds, of the ADR equipment in a field electromagnetic waves at high power are a longer wavelength equivalent and spatial scales from metres to study of a measured section of to investigate the internal structure of lasers. In this article, we report nanometres. Dinantian sediments in a disused of non-conducting substances on a series of experiments in which Some aspects of the field and quarry at Cults, Fife in Scotland, within the ground, like-wise provide rocks of different compositions laboratory ADR equipment involve has confirmed the ability of the relatively low resolution and ground and textures have been exposed certain conditions being satisfied method to distinguish the lithologic penetration. to pulsed beams of wide-band, during the set-up of the apparatus type and their respective thickness The ADR methodology does maser light conditioned dielectric so as to obtain standing wave ranging from limestones through not involve such high-power resonance, to produce a range of oscillations in ADR test sample sandstones, siltstones, seatearths, transmission and achieves much differing atomic dielectric energy chambers and/or in ADR remote- and coals. Borehole data were used deeper penetration than conventional and frequency responses detectable sensing antenna system assemblies. to corroborate the ADR imaging GPRs (Stove 2005). In contrast to by suitable receivers. In this respect, it is important spectrometer. conventional GPRs, which transmit Conditioning the beam by to selectively control the group The signal penetrated more omni-directional electromagnetic dielectric optics creates a synthetic velocity (typically at the speed of deeply into the ground than the 20m signals, ADR technology uses lens effect so that the sensors appear light, 299,792,458m/s) of the radio height of the exposed rock section, directional electromagnetic radiation to have much longer chambers wave and microwave radiation and it showed good correlation with as resonating transmitting and with wider apertures than their as it is emitted or launched by the records from two nearby boreholes receiving beams of energy. Although actual physical size. This effect transmitting antennas into the that extend to lower levels. Reliable some GPRs may have shielded produces narrow coherent beams ground. lithological recognition at ground antennae, they still leak radio of pulsed and mased radio waves In particular, for deep scanning penetration of more than 90m had waves above ground in the opposite and microwaves, which are good for it is important for the launch speed been achieved. direction to the main pathway of illuminating target interfaces and of the wave to be sufficiently slow transmission into the ground. materials. Signals transmitted by to ensure that the wave can be 1. Introduction An ADR beam transmitted ADR are within the high-frequency accurately registered at a precise ADR was developed as an through the ground is a pulsed, radar to millimetre radar frequency zero time location by the receiver improvement over SAR and GPR confocal beam (like a long, range and have wavelengths of less antennas, after the pulse has been to achieve deeper penetration of narrow inverted cone in shape) of than 100m. transmitted. The zero time position the Earth’s subsurface through the coherent (in-phase) radio waves and t(z) in remote sensing or t(0) in creation and use of a novel type of microwaves, producing minimal 2. Methodology geophysics is the start position for coherent beam. dispersion through its confocal 2.1. Description of the ADR ADR range measurements and ADR is used as a geophysical and resonant mased nature. The system must be identified on the received technique to provide a precision transmitted ADR beams have two ADR is a patented investigative ADR signal to determine the true instrument for the accurate components: a long wavefront technique (Stove 2005) that time range (in two-way travel time, geological recognition of rock layers standing wave to achieve deep involves the measurement and usually TWT (ns)) represented by and identification of rock types penetration, and shorter resonance interpretation of resonant energy the received signal, returning from by transmission through the rock waves within the standing wave to responses of natural or synthetic each resonant subsurface reflection medium as well as reflection from enhance vertical resolution. The materials to the interaction of layer.

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Ground level Ground level Subsurface pathways Tx Rx Rx scan direction

Rx Tx received Time Time transmit energy from Transmit pulse Transmit beam subsurface Receive signals earth

Figure 1. The ADR scanner beam transmit and receive pathways Amplitude Amplitude through geological layers when one of the sensors is stationary and Figure 2. Examples of a typical ADR transmit pulse and receive the other is moved progressively away at a regular speed signal

With reference to Figure 1, the displays photographs of the ADR (owing to the high power levels changes (if any) are determined wide-angle reflection and refraction equipment. of the transmit signal). This is by the minerals encountered. In a (WARR) tracking method is used The ADR spectrometer works by especially the case for ground rock mass, the component minerals to (1) identify the upper and lower sending a narrow beam of energy that is saturated in water – where may vary, but in general, sandy boundaries of each stratum, (2) into the ground using microwaves known radar-based interrogation of rocks comprise principally quartz determine the inter-layer beam and radio waves. As it travels the subsurface suffers from signal (SiO2), limestones mainly of calcite velocity and mean dielectric downward, the energy character of attenuation attributable to skin (CaCO3), coals largely of carbon constant (ε) of the material in the beam is altered by the various depth effects, and thus are limited to (C), and clays or shales mainly of each stratum, and (3) identify the rock layers it encounters. The beam, very shallow depths of penetration assemblages of iron- or magnesium- materials in the various strata from which can penetrate to depths up through the earth. alumino-silicates. both the εs, known as molecular to several kilometres, is continually ADR, on the other hand, has Cascading harmonic analysis or atomic spectral lines (after fast reflected back by these same rock been specifically designed to of the emerging electromagnetic Fourier transform (FFT) analysis layers and is recorded on surface. alleviate this problem. The ADR radiation enables the energies and of the received signals) and spectral The recorded data describe transmission, unlike GPR, is not frequencies of the signals released ADR statistical parameters data how rocks and minerals, including a wide-band, omni-directional by the materials to differ sufficiently based on known rock types. hydrocarbons, interact with the dispersive beam. ADR generates a for the rock compositions to be ADR accurately measures the beam as it passes through them and low-power transmission beam that recognised by computer processing. dielectric permittivity of materials pinpoints their composition. The is directional. ADR also transmits Repeated characterisation of the encountered and determines the technology measures the dielectric a resonance beam that helps the ADR signals received from known ε of each layer of rock to an accuracy permittivity of the subsurface as transmit signals penetrate through rocks at known depths in quarries of at least 1:400. With deeper well as characterising the nature of the ground to greater depths than or boreholes has made it possible to penetration and a narrower ADR the rock types based on analysis of conventional GPR systems (Stove classify the principal rock types of beam, the accuracy of dielectric both the spectroscopic and resonant 1981, 1983, 2005). central Scotland and identify them mapping improves, and at 1km energy responses. with confidence in blind tests beside depth, an accuracy of 1:4000 can With traditional GPR technology, 2.2. ADR receiving system logged boreholes. be achieved for the mean dielectrics the depth of signal penetration is The nature of the return signal, its of narrow layers at this depth. inhibited by the ground conditions frequency, energy levels, and phase 2.3. Processing and interpretation The ε is basically the effect that of the received ADR signals a given material has on slowing The analysis of the returned ADR down the ADR transmission 1 ADR transmit antenna signals from the subsurface to the signal. Determining the ε of each 1 ADR receive antenna ADR receiving system is performed layer enables each rock layer to be by FFT analysis of the received mapped with a depth computation ADR data logging spectrum (which includes radio from ground level and can also computer waves and microwaves). This results determine physical properties of the in mathematical and statistical rock layer, such as moisture content, analyses of the received spectrum porosity, and density indices. and the recognition of energy, In general, dielectric values for ADR receiving frequency, and phase relationships. hydrocarbon layers in the Earth tend Antennas control unit More detailed spectrometric to be between 2 and 5 for the author’s gimbal analysis is achieved through the ADR scanner, if water is absent. In platform quantum electrodynamic (QED) geological terms, the main effect on approach (Feynman 1985) by the signal’s velocity as it propagates quantising the entire ADR receive through the material is the water spectrum. In ADR quantum content. For example, air has a ε of theory, this is similar to the equal 1, while water has a ε of 80. Most temperament system of tuning geological materials lie within these musical instruments – in which boundaries. each pair of adjacent musical notes Figure 2 shows the typical ADR signal has an identical frequency ratio. In shape of an ADR transmit pulse generator this tuning methodology, an interval into the Earth and the received (usually an octave) is divided into energy from the Earth. Figure 3 Figure 3. The ADR scanner equipment a series of equal steps, with equal Figure 3. The ADR scanner equipment. Source: http://adrokgroup.com/ 24 ground engineering december 2012

beam is altered by the various rock layers it encounters. The beam, which can penetrate to depths up to several kilometres, is continually reflected back by these same rock layers and is recorded on surface. The recorded data describe how rocks and minerals, including hydrocarbons, interact with the beam as it passes through them and pinpoints their composition. The technology measures the dielectric permittivity of the subsurface as well as characterizing the nature of the rock types based on analysis of both the spectroscopic and resonant energy responses. With traditional GPR technology, the depth of signal penetration is inhibited by the ground conditions (owing to the high power levels of the transmit signal). This is especially the case for ground that is saturated in water – where known radar-based interrogation of the subsurface suffers from signal attenuation attributable to skin depth effects, and thus are limited to very shallow depths of penetration through the Earth. ADR, on the other hand, has been specifically designed to alleviate this problem. The ADR transmission, unlike GPR, is not a wide-band, omni-directional dispersive beam. ADR generates a low-power transmission beam that is directional. ADR also transmits a resonance beam that helps the transmit signals penetrate through the ground to greater depths than conventional GPR systems (Stove 1981, 1983, 2005).

frequency ratios between successive notes. Table 1: Dielectric table from Cults Quarry Traverse line 1 When ADR is applied to Horizon Thickness (m) Dielectric Base Code and possible rock type geological analysis, rocks can be constant (ε) depth (m) genetically classified by notes and octaves using the above 1 0.21 6.6 0.21 AA1 topsoil spectrometric approach – adding 2 0.54 7.85 0.75 AB2 soil-B horizon a new quantum dimension to recording rock music. 3 0.38 11.15 1.12 AC3 soil-C horizon (till)

2.4. Study area 4 0.64 9.56 1.76 AC4 soil-C weathered parent material (till) After several years of preliminary 5 0.42 9.86 2.18 D4 weathered mudstone work, the ADR equipment has undergone sufficient development 6 0.65 3.09 2.83 D4 mudstone to allow extended testing of materials in the field. Initial tests 7 0.2 20.43 3.03 D4 very wet mudstone have been carried out using wide- 8 0.63 8.13 3.66 E1 shale band, conditioned pulses between 1 and 100MHz at a series of sites in 9 0.35 4.35 4.01 D4 mudstone central Scotland. In this article, we 10 0.44 9.91 4.44 D4 mudstone report on a series of findings from a quarry in the late Brigantian Lower 11 0.85 7.94 5.29 D4 mudstone Limestone Formation (Brown et al. 1996; Read et al. 2002) at Cults, Fife 12 0.96 9.67 6.26 D1 coal (NO353089). 13 0.76 10.01 7.02 B1 limestone The main rock types tested in this study were limestone, 14 0.64 5.02 7.66 D1 coal (Largoward Splint?) sandstone, coal, dolomite, basalt, 15 0.48 10.68 8.14 D5 sandy seatearth shale, and mudstone, but elsewhere we have characterised many other 16 0.59 7.05 8.72 C4 sandstone with mudstone rock and mineral types including igneous materials and a range of 17 0.34 16.04 9.07 D1 wet sandy mudstone (finely layered) metamorphic lithologies from 18 0.67 3.22 9.74 C2 muddy sandstone Scotland and overseas. 19 0.65 7.11 10.39 C4 SST + mudstone or shale partings? 3. Results 20 0.55 11.63 10.93 B4 wetter LST + coarser sandy inclusions 3.1. Cults quarry, Fife At Cults, the system was deployed 21 0.53 5.59 11.46 C3 muddy sandstone shooting vertically downwards into the ground along a 20m traverse line, 22 0.63 5.67 12.09 C3 hard SST + mudstone partings 7.6m behind the crest of a 19m high 23 0.51 10.08 12.6 B2 sandy mudstone? quarry face, from which a detailed log of the exposed succession of the 24 0.36 23.31 12.96 E2 shale-wet + coal horizontal sedimentary rocks had 25 0.6 8.99 13.56 B2 Charlestown Main Limestone (LST) been measured. Signal responses were collected 26 0.49 18.58 14.05 B5 Shaley-LST partings, muddy at 0.02m intervals along a traverse line from east to west and then 27 0.43 13.34 14.48 B2 Charlestown Main LST (massive LST) reversed, from west to east. Regular 28 0.6 5.8 15.08 B2 Charlestown Main LST electronic fixes were recorded at 1m intervals to allow the scan lines to 29 0.62 6.41 15.69 B2 Charlestown Main LST be horizontally rectified if there was 30 0.49 4.91 16.18 B3 Charlestown Main LST (karstic surface) textural any variability in the scanning speed. Both traverses were repeated, with 31 0.49 4.95 16.66 B2 Charlestown Main LST consistent results being obtained. For triangulation, WARR scans 32 0.25 15.11 16.91 B3 Charlestown Main LST (karstic surface) textural were then carried out in both 33 0.66 5.99 17.57 B2 Charlestown Main LST directions along this traverse. In this mode of data collection, the 34 0.42 4 17.99 B2 Charlestown Main LST receiver is placed at chainage 0m 35 0.2 25.38 18.19 B3 Charlestown Main LST (karstic surface) textural at the start of the east to west line and the transmitting sensor is moved 36 0.47 17.89 18.66 B2 Charlestown Main LST (massive LST) from east to west for the full 20m length of the traverse. This enabled 37 0.31 35.53 18.97 B3 Charlestown Main LST (karstic surface) textural a reflection and refraction profile to 38 0.36 4.59 19.34 B2 Charlestown Main LST (base of exposed section) be obtained over the first half of the traverse length (ie from 0 to 10m in 39 0.28 19.61 19.62 D3 shale and sandy partings chainage). 40 0.43 22.23 20.05 D3 shale and sandy partings The reverse scan, with the receiver positioned at chainage 20m and the 42 0.39 22.95 20.81 D2 fissured wet SST transmitting antenna moving from chainage 20 to chainage 0m, enabled 43 0.31 29.94 21.12 D2 fissured very wet SST a reflection and refraction profile to continued be obtained over the second half

ground engineering december 2012 25 TECHNICAL paper

the identities of the sediments Table 1 (continued): Dielectric table from Cults Quarry Traverse line 1 concerned were well defined. Horizon Thickness (m) Dielectric Base Code and possible rock type Several further cyclic sequences constant (ε) depth (m) of flat-lying sediments appear to be present beneath the floor of the 45 0.48 8.19 22.09 B4 Charlestown Green Limestone quarry. The records of boreholes put 51 0.65 4.06 25.18 B2 Charlestown Station Limestone down by the British Geological 52 0.33 35.4 25.52 D4 Charlestown Station Limestone Survey in 1994 (Cults No. 1 and Cults Farm) some 300m and 400m 53 0.64 8.37 26.16 B4 Charlestown Station Limestone (+shale partings) to the north-west of the quarry, 54 0.54 5.02 26.69 B2 Charlestown Station Limestone respectively, confirm the presence of further cyclic sequences at 55 0.78 8.93 27.48 B4 Charlestown Station Limestone (+shale partings) approximately the heights detected from the quarry face above. Four 56 0.54 8.39 28.01 B4 Charlestown Station Limestone (+shale partings) limestone horizons, believed to be 57 0.58 5.71 28.59 B2 Charlestown Station Limestone the Charlestown Green (horizon 45 in Table 1), Charlestown Station 58 0.94 8.66 29.53 B4 Charlestown Station Limestone (+shale partings) (horizons 51 to 58 in Table 1), St 61 0.5 40.16 30.83 D2 fissured SST-very wet Monance White (or Blackbyre, horizon 67 in Table 1), and Upper 64 0.53 38.39 33.71 D2 fissured SST-very wet Ardross Limestones (horizon 70 in Table 1), have been identified, the 67 1.98 5.14 37.17 B5 St Monance White Limestone (massive LST) latter three levels coinciding with 70 3.11 7.58 42.12 B6 Upper Ardross Limestone those recorded in the borehole logs. One further suggested bed of 73 1.46 15.96 58.91 C5 SST coarse-grained and fissured limestone, possibly the Lower 74 2.76 16.48 61.67 C5 SST coarse-grained and fissured Ardross Limestone (horizon 80 in Table 1), appears to be present below 80 2.36 9.31 91.11 B7 Lower Ardross Limestone the Upper Ardross Limestone, but in the absence of exposures or more deep boreholes, this identity cannot of the traverse from 20 to 10m as noted by Geikie (1900). From the upper part of the be confirmed. in chainage. Triangulation of each The two coal seams may be the record, for which there is confident If selected horizons from Table interface was enabled by ray tracing equivalents of the Largoward Black identification of the rock types, it 1 are sub-sampled and average and NMO computations, similar Coal, which, in the Drumcarrow is evident that the ε increases with parameters calculated and listed as to the methods used in the seismic Borehole, is 11km to the east. the water content of the rocks. The in Table 2, then some significant industry. Forsyth and Chisholm (1977) dry mudrocks show εs of 3.09–9.91, correlations can be evaluated. These This allowed WARR tables showed that these two coal seams averaging 6.26, whereas their wet exist between mean amplitudes listing depths, layer thicknesses, and consisted of two closely spaced units counterparts ranged from 9.86 and mean frequencies and mean inter-layer εs for each distinct rock at about the level of the Seafield to 23.31, averaging 17.41. In the amplitudes and weighted mean layer (with differing transmission Marine Band, 15m below the Lower Charlestown Main Limestone, the frequencies (Figures 6 and 7). For velocities) to be produced. The Kinniny Limestone. Separating εs for the mass of the rock ranged example, the correlation between processed ADR signal after WARR most of these units are mudrocks between 4.00 and 17.89, averaging mean amplitude and mean analysis and the measured section and muddy sandstones (horizons 7.65, whereas in the texturally frequency for the 12 consecutive are shown in Table 1, where 9–11, 16, 17, 19, and 22 in Table altered limestones with karstic horizons averaged from the Table alphanumeric codes have been 1). Several water-saturated horizons features they varied from 13.34 to 1 layers is -0.9510 (Figure 8), which allocated to the rocks according are present (horizons 7, 17, 24, and 35.53, averaging 22.31. is an inverse correlation and is to their known and interpreted 26 in Table 1). The coals and the The ADR signal actually significant at the 0.001% level or compositions. The signals showed Charlestown Main Limestone have penetrated much deeper than 99.9% confidence level for (n – 2) consistent similarities between the been worked in the neighbourhood. the exposed quarry face, where = 8 degrees of freedom. This value limestones, between the mudrocks, greatly exceeds the tabulated value between the coals, and between of 0.8721 (Table VII, Fisher and 2.55 the sandstones, irrespective of their Yates (1963)) and can be statistically known depths determined from the described as highly significant. exposed quarry face. Figure 8 is actually a plot of the The quarry, which is a 2.54 log-linear correlation between mean Regional Important Geological/ frequency and mean amplitude, Geomorphological Sites (RIGS)- where R = -0.8339 from the linear protected site, had been disused 2.53 fitted trend. The correlation between for several years prior to the study. mean amplitude and weighted The detail of the exposed Visean mean frequency is +0.8937, which

Log mean frequency (MHz) Log mean frequency y = 0.0527x –0.7786 succession, as originally outlined 2.52 is a positive correlation and is again by Geikie (1900) reveals two almost R2 = 0.6955 significant at the 99.9% confidence complete cycles of deposition. At level for 8 degrees of freedom. the base of the face is the massive 2.51 Finally, if the correlation between Charlestown Main (Blackhall) frequency and weighted mean Limestone, comprising several thin frequency is evaluated, it is seen to beds of limestone, several of which 2.50 be another inverse relationship of are separated by ancient karstic -1.0 -0.8 -0.6 -0.4 -0.2 -0.0 –0.9091, which is again significant surfaces. Some 5.7m above this Log mean amplitude at the 99.9% confidence level. This are two thin coal seams with their result suggested that these ADR underlying seatearths. Between Figure 8: Linear correlation of log frequency versus log parametric relationships could be them lies a thin limestone horizon, amplitude a significant way of identifying the

26 ground engineering december 2012 CULTS WMF ROCK CLASSIFICATIONS 350

300

250

200

Weighted mean frequencies (MHz) mean frequencies Weighted 150

100

E1 ShaleD1 Coal AC4 Soil (till) D4 WeatheredD4 Mudstone B1 Limestone AB2 Soil-BAC3 hor.Soil-C hor. C2 Muddy SST B4 Ch Stat LST B8 Limestone?B8 Limestone? D2 fiss. wet SST C5 SST cg & fis E2 Sh-wetB2 Chtn + coal Main B3LST ChtnD3 Main Shale LST & SandyB4 Ch Green LST B5 St Mon W LST C5 SST cg & fis? D4 V Wet Mudstone D1 Coal (LargoC4 Sp.?) SST & Mudstone D5 Sandy Seat-earth B5 Shaley-LST muddy B4 Ch St LST + shaleB6 Upper ArdrossB7 Lower LS Ardross LS C4 SST + Mud or Shale C3 Hard SST + partings C3 Hard SST + partings? B1 Wetter LST + inclusions D1 Wet sandy mudst. (layered) Figure 6. Weighted mean frequency chart of Cults rock layer groupings

CULTS ROCK CLASSIFICATIONS BASED ON MEAN AMPLITUDES 0.9

0.8

0.7

ADR mean amplitudes 0.6

0.5

0.4

0.3

0.2

0.1

Figure 7. Mean amplitude chart of Cults rock layer groupings rocks sampled in Table 2. the rocks at Cults Quarry in Fife at capabilities of a new spectrometer, in real-world conditions. The Cults Quarry survey was to a deeper subsurface depths. known as ADR. Furthermore, The ADR scanner works by relatively shallow subsurface depth. the article has demonstrated sending a narrow beam of energy Further surveys nearby at Lathones 4. Conclusions the ability of ADR to recognise into the ground using microwaves and Higham confirmed the spectral This article has reported the certain lithologic types (viz. coals, and radio waves. As it travels relationships first established for subsurface earth penetration limestones, sandstones, mudstones) downward, the energy character

ground engineering december 2012 27 TECHNICAL paper

of the beam is altered by the Table 2: Principal rock types typecasted in Cults Quarry classified by ADR weighted mean frequency analysis various rock layers it encounters. The beam is continually reflected Selected Horizon Mean ε Mean Mean frequency Weighted mean back by these same rock layers and horizons typecasted amplitude (MHz) frequency (MHz) is recorded at the surface. and classified The recorded data quantify how rocks and minerals, including 25, 27, 28, B2 Chtn Main 8 0.22 351.75 135.07 hydrocarbons, interact with the 29, 31, 33, Limestone beam as it passes through them and 34, 36, 38 pinpoints their composition. The 26 B3 Chtn Main 18.58 0.28 343.89 141.03 technology measures the dielectric LST (karstic) permittivity of the subsurface as well as characterising the nature of 30, 32, 35, B3 Chtn Main 20.28 0.22 358.47 133.35 the rock types based on analysis of 37 LST (karstic) both the spectroscopic and resonant energy responses. 39, 40 D3 shale and 20.92 0.21 353.16 128.15 A key driver in pursuing sandy partings development of ADR technology is 42, 43, 61, D2 fissured wet 32.86 0.42 336.12 280.25 to reduce the number of drill holes 64 SST required to delineate a subsurface mineral or hydrocarbon reserve. 45 B4 Chtn Green 8.19 0.25 341.33 161.9 To do this, laboratory analyses LST of rock specimens and data from 51, 52, 54, B4 Chtn Station 12.55 0.26 341.29 234.09 training holes are used to guide the 57 LST interpretation and analyses of the ADR results. As more samples are 55, 56, 58 B4 Chtn Station 8.66 0.29 345.32 245.22 entered into Adrok’s proprietary LST + sh library, the confidence in the results partings will increase. Another benefit to this approach is that ADR requires no 67 B5 St Monance 5.14 0.74 320.36 317.57 land-use permitting as use of the White LST technology offers a non-destructive, 70 B6 Upper 7.58 0.68 314.76 313.45 environmentally friendly way of Ardross LST remotely deducing subsurface geology. 73, 74 C5 SST 16.22 0.7 321.54 325.23 To date, ADR field deployment fissured has been undertaken at many sites 80 B7 Lower 9.31 0.74 319.9 323.97 in the UK and overseas. ADR Ardross LST databases have been established for the principal igneous, metamorphic, Notes: ε, dielectric constant; LST, limestone; SST, sandstone; Sh, shale; Chtn, Charlestown and sedimentary rock types of Scotland. These databases, which have been confirmed by comparison it is always important to remember deployed as a geophysical service Further research and testing of with newly scanned sections and that it is necessary to determine the by Adrok in the exploration and the ADR system is being conducted driven boreholes, offer considerable ADR characteristics of the local appraisal of subsurface geological to test the depth limits to which potential for future geological rock sequences against known structures and targets (platinum the ADR can penetrate as well exploration. The technique has borehole data. group metals, zinc, nickel, copper, as its reliability and repeatability been used in prospecting for oil, Since 2007, this ADR massive sulphides, uranium, and of material classification gas, coal, and mineral deposits, but methodology has been successfully hydrocarbon deposits). (spectroscopic capabilities).

References

Brown, M A E; Dean, M T; Hall, Strange Theory of Light and R, 1982. “Subsurface Valleys 1981 Report on Ground Data I H S; McAdam, A D; Monro, Matter. New York, NJ: Princeton and Geoarchaeology of Eastern Collection Programme for Block S. K; Chisholm, S I. 1996. “A University Press. Sahara Revealed by Shuttle Radar.” GB1, Macaulay Institute for Soil Lithostratigraphical Framework Fisher, R A; Yates F, 1963. Science 218: 1004–19. Research Experiment 21GB.” In for the Carboniferous Rocks in Statistical Tables for Biological, Read, W A; Browne, M A E; The European SAR-580 Experiment the Midland Valley of Scotland”, Agricultural and Medical Research. Stephenson, D; Upton, B G, 2002. 1981 – In-Situ Data Collection British Geological Survey Technical 6th ed. Edinburgh: Oliver and “Carboniferous” in The Geology of reports “Ground/Sea Truth”, edited Report, WA/96/29. Nottingham: Boyd. Scotland, edited by Trewin, N H, by Sorensen B M; Gatelli, E. Ispra: British Geological Survey. Joint Research Centre. Forsyth, I H; and Chisholm, J I, 251–99. London: The Geological Cimino, J B; Elachi, C; eds. 1982. 1977. The Geology of East Fife. Society of London. Stove, G C, 2005. Radar Shuttle Imaging Radar-A (SIR-A) Edinburgh: HMSO. Stove, G C, 1983. “The Current Apparatus for Imaging and/ Experiment, JPL Publication 82-77, or Spectrometric Analysis and Geikie, A, 1900. The Geology Use of Remote-Sensing Data 230pp. Washington, DC: NASA Jet in Peat, Soil, Land-Cover and Methods of Performing Imaging Propulsion Laboratory. of Central and Western Fife and and/or Spectrometric Analysis Kinross, Memoir of the Geological Crop Inventories in Scotland.” Elachi, C; Roth L E; Schaber G Philosophical Transactions of the of a Substance for Dimensional Survey of Scotland. Norwich: Measurement, Identification and G, 1984. IEEE Transactions on HMSO. Royal Society London A 309: Geoscience and Remote Sensing. 271–81. Precision Radar Mapping, USA GE-22 4: 383–8. McCauley, J F; Schaber, G G; Patent No: 6864826, Edinburgh, Breed, C S; Grolier, M J; Haynes, Stove, G C, 1981. “The GB: US Patent Office. Feynman, R P, 1985. QED: The C V; Issawi, B; Elachi, C; Blom, European SAR580 Experiment

28 ground engineering december 2012 diary

Forthcoming geotechnical events and noticeboard. Send new entries to GE, email: [email protected]

Geotechnical challenges of the Lee Tunnel project 4 December, 6pm. Reading Town Hall, Reading. Deputy head of Lee Tunnel Project management team Roger Mitchell will talk about the geotechnical issues that had to be overcome on Thames Water’s Lee Tunnel scheme, which has now progressed from shaft construction to the tunnelling work itself. To book visit www.ice.org.uk

Fleming Award 5 December, 6pm. ICE, London. Finalists in this year’s Fleming Award, organised by Cementation Skanska, will present their projects to the judging panel and the Geotechnical challenges of the Lee winners will be announced at the Tunnel project, 4 December end of the evening. Contact: Cementation Skanska, tel: 01923 423522 or email: presentation of how Cornwall then during ground investigation of Geotechnical Instrumentation for cementation.marketing@skanska. Council manages its slopes, within the morphological features present. Field Measurements co.uk the highway network, maintained The afternoon session is given over 7-9 April 2013. Cocoa Beach, property and along the South West to construction issues posed by Florida, United States. Remote Sensing in Engineering Coast Path. After an introduction scour features including impacts on This CPD course will offer practical Geology describing the basic geotechnical tunnelling and deep foundations. presentations by engineers, with 11-12 December. Burlington House, theories controlling slope stability, Contact: Ursula Lawrence, email: lectures and displays of instruments London. the most prevalent failure [email protected] by manufacturers. This conference aims to update you mechanisms will be discussed. The Contact: John Dunnicliff, on the latest remote sensing types of hazards and associated Geophysical Studies of an Active tel: 01626-832919, email techniques being used by the public risks will be identified, Landslide [email protected] or engineering geology sector. together with an evaluation of the 23 January, 5.30pm. Room 1.25, visit www.conferences.dce.ufl. Contact: David Entwhistle, various remediation options. Main Building, Cardiff University. edu/geotech email: [email protected] Using illustrated case histories The south Wales coalfield has one from around the county, a series of of the highest densities of inland British Tunnelling Society Debate failures will be identified and their landslides in the UK. Commonly Upcoming Ground 13 December, 5.30pm. ICE, mechanisms and remedial solutions landslides occur on the densely London. demonstrated. populated valley sides, especially Engineering conferences “This house believes tunnel projects The presentation will conclude during periods of heavy rainfall, Slope Engineering in the UK are overstaffed and with an account of the infamous which then threaten housing or 28 November 2012 over specified.” The debate will be North Cliffs Failure at Hell’s Mouth disrupt the urban infrastructure. www.slopeengineering.co.uk held using parliamentary debating that was caught on video in Geophysical techniques can provide rules with 12 minutes each for October 2011; which subsequently a non-invasive, continuous, Instrumentation and proposer and seconder for and went “viral” when uploaded on high-resolution, rapid, low-cost Monitoring against the motion, followed by a YouTube. means for investigating landslide 26-27 February 2013 debate open to the floor, a summing Contact: Joanne Mallard, email: dynamics. The talk will report on ww.gemonitoring.com up and a vote. [email protected] the research findings of a four-year Contact: The BTS secretary, geophysical monitoring study Piling and Foundations tel: 020 7665 2229 or email: The Engineering Geology of Scour carried out on the active landslide Conference [email protected] Features at Mynydd yr Eglwys, Rhondda. 9 April 2013 22 January. Burlington House, Contact: Gareth Far, email: www.pilingevents.co.uk John Mitchell Lecture London. [email protected] 16 January, 5.30pm. ICE, London. Scour features are encountered all Deep basements and Dr Mourice Czerewko will present through London’s flood plains, 53rd Rankine Lecture underground structures the 2013 John Mitchell Lecture on unexpectedly producing substantial 20 March, 5pm. Imperial College, 1-2 October 2013 assessment of pyritic Lower Lias thicknesses of gravel. Debate has London. www.gebasements.co.uk mudrocks for earthworks. centred on their formation, from The 53rd Rankine Lecture will be Contact: BGA coordinator, fault controlled scour features to presented by Professor Michele Slope Engineering tel: 020 7665 2229 or email: relict pingos. The day will start with Jamiolkowski on the subject of 13 November 2013 [email protected] a presentation on the geology of “Soil Mechanics and the www.slopeengineering.co.uk these features highlighting a observational method: Challenges Slope Management in the Public proposed classification system. at the Zelazny Most copper tailings Tunnelling Realm This will be followed by two disposal facility”. 27-28 November 2013 16 January, 6pm. New County presentations, firstly detailing Contact: BGA coordinator, www.ncetunnelling.co.uk Hall, Truro. practical issues for locating scour tel: 020 7665 2229 or email: This talk provides a visual features by geological context and [email protected]

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