Doctoral and Master theses prior to ETD mandate (pre-2009)

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This collection houses Doctoral and Masters theses produced prior to the introduction of mandatory submission in November 2009. Despite our best efforts, the coverage is not complete, particularly in earlier years. For newer theses see the Doctoral and Master collections respectively.

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1 GHz Programmable Analog Phase Shifter for Adaptive Antennas
(1997) Chua, Marcial K.
Adaptive antennas are currently being considered as a means to improve spectral efficiency of wireless networks. They can be used to spatially separate different mobile user, by forming radiation pattern nulls at the interfering signals. However, the relatively high cost of adaptive antenna systems compared to non-adaptive antennas has hampered their commercial application. The purpose of this thesis is to investigate the feasibility of realizing an integrated circuit that will implement a one GHz programmable analog phase shifter, an important building block of adaptive antenna systems. This could lower the system's cost of adaptive antennas. The programmable analog phase shifter is comprised of a 900 phase shifter, a variable gain amplifier, a summer and a digital-to-analog converter. The resulting chip area is small enough to allow 16 complete phase shifter circuits to be included in a single package, thereby allowing control of an array of 16 antenna elements.
A 1 V Floating-point Analog-to-Digital Converter for Portable Communication Devices
(1998) Hayashi, Takayuki
With the growing demand for portable communications devices, power consumption has become increasingly critical in VLSI designs. In mixed-signal circuits, the push for lower supply voltage to reduce power dissipation in digital systems has forced analog systems to lower their supply voltage as well. This thesis deals with the design of a low power low voltage analog-to-digital converter (ADC) that operates from a single 1 V power supply. Two circuit techniques are utilized to enhance the performance of the converter. First, floating-point technique is employed to improve the dynamic range of the converter by providing a non-uniform quantization of the analog input. This allows the ADC to achieve a wide dynamic range without using high-resolution components. Second, current-mode technique is chosen because it offers characteristics such as good signal swings, high speed and small circuit area. The ADC was implemented using a 0.5 [mu]m, 1V CMOS process with low threshold voltage transistors. Simulation results of the core ADC cell indicate an 8-bit resolution while dissipating only 170 [mu]W. The complete floating-point ADC exhibits a dynamic range of 12 bits, a conversion time of 63 [mu]s and a power dissipation of 450 [mu]W. The total area excluding bonding pads is 1 mm 2.
A 1 V Low-power CMOS Process
(1998) Pede, Luigi Di
To reduce the size of portable telephones and other portable data communicators, and to increase the talk and use time, it is essential to reduce the power consumption of the LSI circuits that are the main components of these devices. Because the power consumption of CMOS transistors is proportional to the square of the power supply voltage, the power consumption can be dramatically reduced by cutting the power supply voltage. This will only be true however, if the threshold voltage can be scaled down proportionately to the supply voltage without increasing the standby current which otherwise increases due to subthreshold leakage. This thesis deals with the optimization of the MOSFET device structure as a means of providing 1V low power circuits in a submicron CMOS VLSI technology. Using process and device simulations, a 300 mV threshold voltage, sub 90 mV/dec subthreshold swing 1 $\mu$m LVCMOS process was developed. Due to the fact that conventional process simulations are not fully calibrated to model exact process conditions encountered experimentally, process simulations were used only as a starting point from which experimental results were used to refine the five most critical fabrication steps. High frequency and quasi-static C-V tests on n$\sp+$ and p$\sp+$ poly gates fabricated with different gate oxide thicknesses were used to establish the fabrication conditions necessary to prevent dopant penetration or polydepletion effect in 140 A gate oxide. Deep, low concentration (2 $\times$ 10$\sp{16}$ cm$\sp{-3}$) n- and p-wells with flat profiles were implemented along with suitable threshold voltage adjust implants and shallow (0.2 $\mu$m) source/drain junctions to achieve complementary long-channel devices with 300 mV threshold voltages and $<$80 mV/dec subthreshold swings. A 12 mask 16 mm$\sp2$ test chip was constructed to fully characterize the process.
1 V, 1.9 GHz CMOS Mixers for Wireless Applications
(2001) Ye, Song
This thesis deals with the design and implementation of 1 V 1.9 GHz mixers using CMOS technology for CDMA applications. The use of CMOS allows the implementation of the mixers on the same chip with the rest of the analog and digital circuits economically while achieving high performance. The mixers topologies explored are a dual-gate mixer and a back-gate mixer. The dual-gate mixer is designed in a 0.5 um SOI process and the back-gate mixer is designed in a 0.25 um standard bulk CMOS process. Equations describing the nonlinear behavior of the CMOS dual-gate mixer are derived. The analysis yields guidelines for improving third-order intermodulation distortion of the mixer. The dual-gate mixer exhibits 1.8 dB conversion gain, -0.8 dBm IIP3 and 9.8 dB noise figure at 1.9 GHz while operating from a 1 V supply with a power consumption of 3 mW and a die area of 1.44 mm2. The back-gate mixer utilizes the inherent lateral bipolar transistor in CMOS. Device simulations were performed to analyze the behavior of the lateral bipolar transistor and extract a model for it. The characteristic of the transistor were verified through measurements. The mixer circuit only draws 1.3 mW from a 1 V supply. The measurement shows a conversion gain of 6.5 dB an IIP3 of -3.5 dBm and a noise figure of 9.7 dB at 1.9 GHz. The chip area is 1.4 mm2.
1,2-DCA and VC degradation by VC-enriched and 1,2-DCA-enriched anaerobic cultures
(2004) Bagard, Olivier
An anaerobic mixed microbial culture which degraded trichloroethylene to ethene was enriched on 1,2-dichoroethane (1,2-DCA). This enrichment and KB1-VC/H2, an anaerobic mixed microbial culture which was capable of sustained vinyl chloride (VC) degradation, were inocula for inhibition experiments where the interactions between 1,2-DCA, VC and chloroform (CF) were investigated. The 1,2-DCA culture degraded 1,2-DCA first within 10 days and eventually degraded VC after a sixty-day lag. The VC culture could degrade VC and 1,2-DCA simultaneously within ten to forty days. In the 1,2-DCA culture, 1,2-DCA was likely degraded by an organism suspected to be Syntrophus-KB1. In the VC culture, 1,2-DCA was degraded by Dehalococcoides-KB1 or by the unidentified organism. VC was a competitive inhibitor of 1,2-DCA degradation with an inhibition constant of 55muM. CF was a non-competitive inhibitor of 1,2-DCA and VC degradations: inhibition constants were equal to 10muM for 1,2-DCA degradation and 1.6muM for VC degradation.
A 1-V, CMOS on SOI, 1.9-GHz CDMA Low Noise Amplifier
(2000) Jin, Heng
This thesis deals with the design and implementation of a 1V, 1.9GHZ low noise amplifier (LNA) using a 0.5[mu]m CMOS on SOI technology with 3 levels of metal. The amplifier is optimized for CDMA applications operating in the 1.93-1.99GHz band. The inductive degeneration topology used in the LNA implementation provides low noise and low power dissipation. The use of CMOS on SOI technology may lead to an optimum single chip implementation of both the analog and digital building blocks of a 1.9GHz transceiver operating from a 1V supply. Such an implementation offers reduced cost and improved reliability. The LNA consists of two amplifying stages with on-chip inductors and capacitors. At 1.96GHz, the amplifier has a 1.9dB noise figure, a 14dB gain and a 3dBm IIP3. It also exhibits 17.4dB input and 28.3dB output return losses respectively in a 50[Omega] system without external matching networks. The circuit draws 10.6mW from a 1V supply and the chip area is 1.1 x 2.4 mm2.
1. Synthetic applications of aziridines: New approaches to the development of asymmetric catalysts. 2. Studies of new reactivity fo p-tolylsulfinayl amides towards olefins
(2003) Krasnova, Larissa B
The new N,N-ligands have been synthesized. It was shown that Cu(I) coordinates to the ligands. Enantiomerically pure forms of this ligand were obtained and applied to the cyclopropanation reaction, where the copper catalyst revealed unexpectedly high diastereoselectivity in comparison with the ruthenium catalyst. Observed diastereoselectivities are superior to the known copper catalyzed cyclopropanation. New reactivity of the sulfinyl amide was discovered. Reaction between alkenes and sulfinyl amides in the presence of POCl3 was found to proceed with the formation of β-chlorosulfides. Optimized reaction conditions were applied to a wide range of substrates. In the absence of nucleophile under Lewis acid conditions p-tolylsulfinyl amide reacted with α-methylstyrene with the formation of allylsulfoxide. This chemistry provides a reasonable alternative to currently used oxidative methods of sulfoxides synthesis.
A 1.8V 2nd-Order [sigma delta] Modulator
(1999) Yang, Wei
Low-voltage, low-power analog-to-digital converters provide a critical interface in portable mixed-signal electronic systems. The robustness and tolerance of the sigma-delta modulator technique over other data-converter techniques make it an ideal choice in applications where low voltage and high-dynamic range are a must. This thesis deals with the design and implementation of a low-voltage, low-power 2nd-order sigma-delta modulator with a single 1.8 V power supply using conventional threshold voltage transistors. All the circuit blocks are integrated on one chip, and the input common-mode voltage is set at mid-rail, resulting in low power dissipation, minimum off-chip components, and high efficiency, flexibility and compatibility. The design is useful for voice applications in personal communications systems supplied by two nickel-cadmium or alkaline batteries. The modulator consists of four circuit blocks: the biasing, the operational amplifier, the comparator-latch, and the four-phase clock generator. A high DC gain, large output swing operational amplifier with a low-voltage power supply was implemented using a fully-differential folded-cascode input stage followed by a common-source output stage, combined with a switched-capacitor common-mode feedback circuit. Based on fully-differential switched-capacitor techniques, the modulator was implemented using a 3.3 V, double-poly, 0.35[mu]m CMOS process. The modulator exhibits a 15-bit dynamic range for a 7 kHz bandwidth, and a 14-bit dynamic range for a 20 kHz bandwidth at an oversampling frequency of 2.56 MHz. The complete 2nd-order modulator has a power dissipation of 0.99 mW, and occupies 0.31 mm2 of the area excluding bonding pads.
A 10 bit, 50MS/s, Low-Power Pipelined A/D Converter for Cable Modem Applications
(2001) Hamedi-Hagh, Sotoudeh
Cable modems have been recently developed for high speed, bidirectional communication over the broadband hybrid fiber-coaxial network. Such modems use mixed-mode circuits to achieve high performance interactive multimedia communications. The digital back-end circuits in the cable modem are implemented in a submicron CMOS process for low power dissipation and high speed of operation. To realize low cost and single chip modems, the analog front-end circuits must be implemented together with the digital circuits on the same chip. A crucial block in the cable modem is the high performance A/D converter which operates in the in-band downstream receiver and links the analog front-end to the digital back-end circuitry. This thesis deals with the design of a pipelined A/D converter realized using a one bit per stage pipelined architecture for use in cable modems. The A/D converter includes the input track-and-hold circuit, clock timing generator, digital synchronization block and the pipelined stages. The pipelined A/D converter is implemented in a 0.25-[mu]m, 2.5-3.3V CMOS process, with single layer of polysilicon and 5 levels of metallization and uses an area of 3.2mm2. The prototype exhibits a 10 bits resolution at 50MSample/s and 57dB SNDR while dissipating 65mW from a 2.5V supply voltage. The DNL and the INL are -0.5LSB and 0.95LSB respectively and the area of the core excluding pads is 1.2mm2. Compared to the best previous design with the same resolution and sampling speed, this design achieves the same dynamic range at lower supply voltage, lower power dissipation and with a smaller core area.
A 100-200 MHz Ultrasound Biomicroscope
(1999) Knapik, Donald Andrew
Clinical ultrasound imaging systems capable of producing real-time, economical, cross sectional images of soft tissue are in widespread use. The resolution of these system is not sufficient for certain specialised applications. A 100-200 MHz ultrasound system providing resolution from 14-35 [mu]m has been produced. Transducers were custom built using a novel design. The properties of two transducers, one at 100 MHz and the other at 200 MHz, have been characterised and they compare well with theoretical values. A minimum insertion loss of 18 dB has been measured. Real-time images have been obtained at 100 MHz. At 200 MHz higher quality images were created with a slower, zone focus scan. Adequate contrast and penetration are shown in images of ocular tissue, superficial skin and a coronary artery. These examples show the potential for clinical utility of this system in assessing superficial conditions such as corneal disease, melanoma and atherosclerosis.
A 131-Year High-Resolution Record of Coccolith Assemblages in Laminated Sediments from the Arabian Sea
(2010-09-03) Akrami, Maryam; Bollmann, Jorg; Geology
This study looked at a 131-year high-resolution record of coccolith assemblages in laminated sediments from the Arabian Sea. The SO90-39KG core obtained from the northeastern Arabian Sea was sampled at an annual resolution for the period of 1861-1993 A.D. Analyses of Scanning Electron Microscope (SEM) images of these samples revealed a declining trend in the relative abundances of the upper to mid photic zones coccolithophore species and an increasing trend in the relative abundances of the lower photic zone coccolithophore species over the 20th century. These trends could be the result of a reduction in paleoproductivity caused by the deepening of the nutricline and the thermocline due to a warming climate. The 1883 A.D. Krakatau eruption was also evident in the results as decreased paleoproductivity. Similarities between the observed trends and monsoon precipitation as well as sunspot cycle records were also observed. No particular similarity with El-Nino Southern Oscillation (ENSO) record could be detected. Caution should be observed regarding the correlation of the results obtained here to past climatic and geologic events.
15-Hydroxyprostaglandin dehydrogenase protein expression in human preterm fetal membranes
(2006) Rizek, Rose Marie
Prostaglandins are important in the onset of labour. 15-hydroxyprostaglandin dehydrogenase (PGDH) metabolizes prostaglandins and is downregulated in preterm labour with and without infection. We detected a predominant 29kDa and 55kDa form of immunoreactive-PGDH in preterm chorion and amnion, respectively. 29kDa PGDH expression was unchanged with preterm premature rupture of membranes (PPROM), gestational age, glucocorticoid administration or subclinical inflammation. However, in amnion, 55kDa PGDH increased with PPROM at
157-nm radiation induced bragg gratings in silica optical waveguides
(2003) Chen, Eddy G
This thesis reports the first detailed study of Bragg grating writing using 157-nm radiation. The 7.9-eV photon from the 157-nm laser is attractive for inducing strong index changes in germanosilicate and fused silica. Fiber Bragg gratings were written in standard telecom fiber (SMF-28), with index modulation of ∼1.7 × 10−4 in hydrogen-free SMF-28. The gratings have good long-term stability, and sidelobe suppression of 17 dB without apodization. The index modulation improves to ∼6 × 10−4 and Δn∼1.8 × 10−3 in hydrogen-loaded SMF-28. Bragg gratings were fabricated in pure fused silica holey fiber, yielding Δn∼1.4 × 10−3 at 90 kJ/cm2 fluence exposure, and offered good cladding mode suppression. Bragg gratings were also written within silica-on-silicon planar waveguides and buried waveguides in fused silica blocks. The results demonstrate an alternate laser source for writing fiber Bragg gratings not requiring photosensitivity enhancement in germanosilicate waveguides, and is practical for writing gratings in pure fused silica holey fiber.
1kW 10V to 400V converter for a solid oxide fuel cell
(2007) Cheng, Clarence
A new industry solid oxide fuel cell outputs 10V instead of 25V at 5kW, the power level intended for residential use. A 5kW 10V to 400V converter is designed using a simple cost-efficiency optimized approach. Power loss is modeled based on ideal waveforms allowing independent optimization for each component. Four topologies are analysed at a switching frequency of 20kHz and $0.9CDN per Watt: the voltage-fed H-bridge and push-pull prove to have a much lower cost function than their current-fed forms. A 1kW voltage-fed H-bridge prototype is built, working up to 417W output with 86.3% efficiency and 292V output. Projections to the desired 1kW load indicate the converter would output 350V with 89% efficiency. A conservative estimate for the cost of the high volume production of the prototype was sim;$153 USD. The estimate for the high-volume production of the 5kW unit was sim;$115 USD/kW.
2-Ethylhexanol: A Potential Biological Indicator of Occupational Exposure to the Plasticizer di(2-Ethylhexyl)phthalate
(1997) Ellis, Shawn Alfred
The urinary metabolite 2-ethylhexanol (2-EH) was investigated as a potential biological indicator of occupational exposure to the plasticizer di(2-ethylhexyl) phthalate (DEHP). Urine and personal air samples were collected for 2.5 workshifts from seven plasticized resin workers and two controls. DEHP concentrations in workplace air were below 0.25 mg/m$\sp3$ (provincial limit 5 mg/m$\sp3).$ Airborne 2-EH, which was produced from heating DEHP, ranged from 0.92 to 4.5 mg/m$\sp3.$ Urinary 2-EH was determined by a new analytical method which used solid phase extraction of 2-EH followed by esterification with trichloro acetic anhydride and analysis by GC-ECD. The limit of detection was 0.01$\mu$g/ml. Urinary 2-EH in exposed workers generally increased following each workshift and ranged from undetected to 13.54$\mu$g/mmol creatinine. Analysis of the correlation between DEHP exposure and urinan, 2-EH was inconclusive due to the limited sample size of the study. Neither DEHP nor 2-EH (airborne or urinary) were detected in controls.
2-Indolylphosphines: Synthesis and reactivity
(2007) Lam, Edmond
Organophosphorus compounds bearing indolyl substituents has been synthesized. Using an animal protecting group to direct lithiation and electrophilic trapping with a chlorophosphine, the key P--C bond was formed at the 2-position of indole. Subsequent removal of the aminal protecting groups with NaBH 4 led to the formation of phosphines where the indolyl nitrogen centre may now serve as a secondary site of reactivity with a variety of functional groups to generate a diverse range of phosphines of varying electron-withdrawing and electron-donating character. The stepwise, controlled coordination of the 2-indolylphosphines on Ru 3(CO)12 was examined. Reactions of HL (HL = 2-indolylphosphine) with Ru3(CO)12 led to the formation of Ru3(CO) 11(HL) where HL was mono-coordinated through the phosphorus atom. Gentle heating of Ru3(CO)11(HL) resulted in the formation of Ru3(CO)9(mu-H)(mu3,eta2-L) in which the NH proton has migrated to the triruthenium core to form a bridging hydride ligand. Through its deprotonated nitrogen atom, the indolyl moiety bridged over the face of the triruthenium core, bonding to the two ruthenium centres to which the phosphorus atom is not bound. 2-Indolylphosphines behaved as anionic 6-electron P, N-donors in this mode of coordination. Monodentate 2-indolylphosphines, in the absence of base, served as 2-electron P-donors in reaction with Pd(COD)Cl2 to form [Pd(L)Cl(mu-Cl)] 2 dimers. In the presence of base, one of the dimers aggregated into a 58-electron butterfly cluster Pd4Cl4[P(C6H 5)2(C9H8N)]2[mu3,eta2-P(C6H5) 2(C9H7N)]2 where the ligand served in two positions as a neutral 2-electron P-donor and in one position as an anionic 4-electron N-donor. Lastly, a new generation of 2-indolylphosphines has been prepared with an emphasis on increasing electron richness of the phosphine and increasing overall steric bulk. These phosphines featured non-phenyl phosphorus substituents and phenyl groups on the indolyl nitrogen centre. Preliminary results showed that 2-indolylphosphines could serve as effective ligands for the Heck-Mizoroki and Buchwald-Hartwig animation reactions involving aryl bromides, but their performance in reactions with aryl chlorides was poor. 2-Indolylphosphines served as scaffolds for the synthesis of new unsymmetric P, P and P, N-bidentate ligands which feature a rigid indole backbone. X-ray studies of the Pd(II) square planar complexes provided insights into the nature of the bonding geometry of these P, P and P, N-bidentate ligands.
2-Vinyloxiranes as synthetic equivalents to [beta, gamma]-unsaturated aldehydes: applications and the total synthesis of cryptophycin analogues via a scaffold approach
(2006) Maddess, Matthew L
Beta, gamma-Unsaturated aldehydes have rarely been used as building blocks in synthetic organic chemistry, presumably due to their very low stability with respect to olefin isomerization. We have found that treatment of 2-vinyloxiranes with an appropriate Lewis acid in the presence of a variety of nucleophiles affords a diverse array of products which are difficult to produce by other means. To date, protocols have been developed for the racemic and asymmetric allylation, crotylation, and propargylation of the in situ generated electrophiles. Similar chemistry has been developed with alkynyloxiranes that affords a second route to products with clearly differentiated pi-systems. The products of the rearrangement/trapping sequence are useful in a variety of contexts. For instance, the application of Prins-type reaction conditions upon various bishomoallylic alcohols affords interesting pyran products, a common structural motif in natural products. Alternatively, we have shown that selective homologation of the terminal olefin via cross-metathesis is possible and yields a key fragment of a pharmacologically active (anti-cancer) class of natural products known collectively as the cryptophycins. This aspect of the project has evolved to the concise synthesis of a library of cryptophycin analogues through a scaffold approach. In addition, subjection of homoallylic homopropargylic alcohol to enyne metathesis affords interesting carbocyclic dienes. These products are suitable substrates for further reaction in Diels-Alder processes with potential application to natural products such as (+)-lepicidin A, a potent insecticide. Other tangentially related projects have been explored, and include our efforts to prepare both (+)-compactin and oxy-compactin utilizing ring-opening of an oxabicycle, crotylation, and ring-closing metathesis as key steps. This project remains ongoing, and has generated additional chemistry such as the preparation and utility of cyclic enol carbonates for the synthesis of stereochemically defined silyl enol ethers and vinyl triflates.
A 2.5 Gb/s CMOS Add-Drop Multiplexer for ATM
(1999) Golinescu, Nicolae
Asynchronous Transfer Mode (ATM) is used to accommodate the simultaneous transmission of voice, data and image, in an integrated manner using the same network. It is based on the transfer of fixed-length cells. In order to connect the source of information to the optical transmission line, a universal ATM functional block, the Add-Drop Multiplexer (ADM), is used. The block adds or extracts cells (53 byte words) from the high speed data bus. The objective of this work is to implement the ADM in 0.5[mu]m CMOS technology, running at 311 MHz or 2.5 Gb/s. The ADM consists of an Input Buffer which provides the selection logic for the cell extraction, an Add Module used to insert ATM cells into the high speed data bus, a Drop Module used to extract the cells from the high speed data bus and an Output Module that prepares the cells for physical transmission. The chip was designed and successfully implemented. It occupies an area of 14.7 mm2 and dissipates 4.5 W of power. The chip was tested functionally at 20 MHZ. High speed testing was also performed at 311 MHz by focusing on the critical path of the chip. A good correlation was obtained between simulation and experimental results.
2D & 3D FE Analysis of Fir-tree Joints in Aeroengine Discs
(1998) Kanth, Parmjit Singh
A comprehensive 2-D and 3-D finite element study is undertaken to examine the effect of the critical geometric features and interface conditions in the fir-tree region of a turbine disc upon the stress distribution at the blade/disc interface. Three aspects of the work were accordingly examined. The first was concerned with the stress analysis of the critical geometrical features and interface conditions (friction) of various fir-tree configurations, thus enabling the evaluation of the critically loaded regions in the disc. The second was concerned with the three-dimensional finite element analysis of the assembly, so as to examine the effect of the skew angle upon the triaxial state of stress and load sharing between the teeth in turbine discs. The third aspect was devoted to the validation of the FE predictions using existing photoelastic stress freezing results. The outcome of the work reveals the importance of the contact angle, upper and lower flank angles, number of teeth, and skew angle upon the stress field. Frictional conditions at the interface were also investigated and the results reveal that they play a minor role in determining the level of interface stresses.
3-D Seismic Imaging of Complex Structures in Near-Surface Deposits
(1997) Siahkoohi, Hamid Reza
One of the most important methods of investigating the geological structure of sedimentary rocks is controlled source reflection seismology. Reflection seismology has traditionally focussed largely on petroleum exploration problems, i.e., imaging formations in consolidated sedimentary rocks at depths in the range 0.1-10 km. However, hydrogeological investigations and large engineering enterprises also may require detailed pictures of subsurface structure, but in relatively unconsolidated surficial sediments at typical depths of 3-100 m. If subsurface structures are not too complex, relatively simple two dimensional (2-D) seismic profiling methods can provide detailed cross-sections of the lithological stratigraphy and structure. But, as has been well demonstrated in petroleum exploration, three dimensional (3-D) surveying methods are required to obtain an accurate picture of complex structures. Nowadays, especially in areas of former glaciation, increasing efforts are being placed on using 2-D seismology to obtain detailed images of near-surface geology in connection with groundwater, waste disposal, and engineering projects. But, although results are very gratifying in some respects, the resolution of very local structures by 2-D seismic surveys has been insufficient to identify possible hydrogeological, and engineering problems. It is natural to consider whether 3-D seismic surveying in shallow environment might yield beneficial results similar to those it provides in petroleum seismology (always presuming that survey cost can be restrained). To address this question, I have investigated the imaging capability of 3-D multi-fold high-resolution reflection seismology in near-surface complex deposits and designed a form of three-dimensional seismology suitable for hydrogeological, geotechnical and other similar surficial exploration purposes. A test 3-D survey was carried out successfully and its results surpassed expectations in several ways. The survey was relatively easy to carry out using standard engineering scale seismic equipment and a 3-4 person crew. It provided a cube of stacked data with fairly high dominant frequency ($\sim$300 Hz) covering a subsurface volume of 220 x 220 x 200 meters with a trace bin of 3 x 3 meters. In addition to the reflectivity image, the survey provided a velocity model to $<$100 m depth that assisted greatly in geological identification of the reflectors and was good enough to permit post stack depth migration. Details of the stratigraphy are much more clearly revealed in the 3-D stacked sections than in nearby 2-D sections. Generally, tills are expected to be massive units. However, the 3-D seismic sections show strong, highly continuous, reflectors within the till deposits which are of much greater continuity and extent than has previously been realized. Foreset bedding can be recognized in one of the sedimentary strata. Results indicate that high resolution 3-D seismic surveying can contribute effectively to the detailed hydrogeological and engineering assessment of sites with complex geology.

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