Kenneth L. Zonge (1936–2013) was geophysicist and entrepreneur noted for his advances in the field of induced-polarization (IP). Zonge was the recipient of the SEG's Cecil Green Enterprise Award in 1995.
Hughes, L., Zonge, L., Van Reed, E., Carlson, N., Lide, C., Urquhart, S., Wynn, J., Young, G., and Roth, J. (2014). ”Memorials.” The Leading Edge, 33(3), 354–356.doi: 10.1190/tle33030354.1
Several decades ago, if you arrived early enough at Zonge Engineering’s Tucson office, you might have noticed an unassuming man with a well-worn broom, diligently sweeping the porch of whatever debris the warm desert winds had deposited the previous evening. You would have received a smile and a chipper welcome, and if this was your first visit, an enthusiastic escort into the building. Passing a poster of misspelled delivery labels (Zeonge, Zonke, Ponge, Donge, etc.), he would usher you into an open-architecture expanse, its soaring truss ceiling an- chored by a maze of cluttered cubicles. Emanating from these, you could hear a muffled cacophony of keyboards rattling out reports, the shuffling of geophysical sections, the slurping of fatally strong coffee, a field crew chief fuming about someone taking his truck keys, a woman excitedly shout- ing in Mandarin into a phone, a man with a Santa beard wielding a soldering iron, and a cluster of geo nerds locked in a fierce debate about the terminal velocity of a grape thrown from the Empire State Building. Who could possibly preside over such an eclectic mélange of “Zongies”? Looking into the eyes of your tour guide and groundskeeper, you had your answer. He was, in fact, Dr. Kenneth L. Zonge, an industry icon in leading-edge electrical geophysics and president of the company.
Ken Zonge grew up in Pennsylvania and Ohio. Joining the Army at 18, he was stationed as an electronics technician in Alaska, a wondrous place that drew him back after his military service to employment in fishing and trapping. It was on the banks of the Kenai River that he met Kim, soon to be his bride. Three children followed — Gene, Tammy, and Lynn. Ken obtained a B.S. from the University of Alaska (1962), followed by an M.S. from the University of Arizona (1965), both in electrical engineering. The family then returned to Alaska, where Ken took up residence as associate professor at the University of Alaska in Fairbanks, focusing on lightning research and developing portable self-potential instrumentation.
The next move was back to the University of Arizona, where Ken began a Ph.D. program in geophysics under John Sumner, one of the pioneers of the induced polarization (IP) method developed in the 1950s by Newmont Mining and MIT. Unlike DC resistivity, which generally is not diagnostic in distinguishing mineralization from lithology, IP exploits ion-mobility effects arising from mineralization and alteration. Because IP effects were known to vary spectrally and thus depend on the timing of the measurement, Ken became interested in developing a broadband IP method that would more fully characterize mineral responses and perhaps distinguish them from noneconomic sources of polarization (e.g., clays or barren pyrite). Drawing on his electrical engineering background, he dubbed it complex resistivity (CR).
Although time-domain IP methodology was widely utilized in that period, Ken embraced the promise of frequency domain for broadband IP in what he correctly envisioned as an emerging new generation of digital instrumen- tation, soon to revolutionize data ac- quisition through bandpass filtering, in situ FFT analysis, stacking, etc. His early tests utilized off-the-shelf mini- computers and auxiliary gear piled on the tailgate of his iconic Chevrolet Suburban, affectionately known as the Red Baron. One early indication of the digital age of electrical geophysics came in his whimsically entitled semi- nar, “Backpacking a Box Full of Bits into the Bush.”
Box of bits in hand, Ken attract- ed a crew of bright field assistants, including Claude Wiatrowski, Jeff Wynn, Bob Staley, Gary Young, Em- mett Van Reed, Carlos Aiken, Dave Rabb, and Bobby Jack, as well as several strategic supporters in industry, particularly Frank Fritz. Their initial field tests for several mining companies (notably AMAX Inc.) showed indications that CR was indeed capable of mineral discrimination. In 1972, Ken loaded several eager assistants into the Red Baron and drove to Anaheim to present their results at the SEG conference. Packed four to a room and subsisting on cheap hamburgers, they did not seem ready for prime time, but Ken’s SEG talk was revolutionary — so much so that the question period brought strong, intensely personal opposi- tion from several icons of analog time domain, who doubted the results.
Unexpectedly, a week later, Ken received a letter from the same critics, offering to buy out his fledgling operation. For a second, he thought about it. Here he was, working out of his bedroom with little but mounting debts to show for it all. That dire predicament had been underscored when, as Ken was repairing some broken equipment, Kim marched in and announced: “I have a name for this company of yours: Zonge Engineering and Research Organization, which spells out as ZERO — which is exactly what we have in the bank account right now!” The name stuck, but fear did not. His response to the critics: File their letter in the trash can, and file a patent on CR (U. S. 3967190).
One problem remained in interpreting CR data. For large arrays, and especially at the low resistivities and higher frequency range characteristic of many mining surveys, the mineral signatures were overwhelmed by electromagnetic coupling between the array wires. At the time, coupling was typically addressed by comparing field data to reference curves, but CR required an automated, inverse solution. As he was completing his Ph.D., Ken had met another graduate student, Jeff Wynn, who was looking for a dissertation topic. Teaming intellect and practicality, they came up with an algorithm to first remove the calculated electromagnetic coupling response of a homogeneous earth, then iteratively remove the responses of as few layers as possible to achieve a minimal-coupling result. The dominant coupling response on the Argand diagrams was effectively eliminated, leaving well-behaved CR residuals. Another round of papers published in Geophysics and at con- ferences unleashed yet another wave of criticism, which was soon followed by the sincerest flattery of imitation. But word was out. Zonge Engineering, now relocated from the Zonge bedroom to a former bicycle shop, was fielding crews for an increasing number of mining clients. CR’s FFT approach placed unprecedented demands on waveform stability, transmitter-receiver synchronization, and signal processing. At first, these were handled in a central re- cording truck with rack-mounted, AC-powered equipment. But greater logistical flexibility was needed for remote areas and for other electrical techniques. One of Ken’s greatest contributions was development of a multichannel, backpack- portable, computer-based receiver, the GDP-12, as well as a stable, high-powered transmitter. For field Zongies with the lungs and legs for it, the most inaccessible mining areas became fair game with the new gear. Equipment sales to international industry clients, even competitors, became a critical part of ZERO’s services.
The GDP-12 opened up new geophysical vistas as a multipurpose system. In the late 1970s, Ken developed con- trolled-source audiofrequency magnetotellurics (CSAMT) as a practical exploration tool, and other techniques, including MT and TEM, were added. New applications were developed, often self-funded (confirming the “Research” part of the company name). One of the most significant was mapping CR effects of geochemical alteration overlying petroleum deposits, which occupied a good part of that research effort into the 1980s. Geotechnical and environmental work joined the mix of energy exploration in the following decade.
In the mid-1980s, a depression in mineral and petroleum prices nearly closed the company’s doors. Zonge Engineering entered into Chapter 11 bankruptcy, laid off the staff, and awaited seizure by the bank. But Ken’s indomitable spirit and support from his loyal employees pulled out a miracle. The company returned as a dominant force in electrical geophysics, added new staff, and expanded its offices in Australia and Chile. The Australian enterprise provided an especially fruitful collaboration between Australian and American geophysical talents and opened up a geologically demanding proving ground for Zonge equipment. New endeavors followed: a fast turnoff TEM system for UXO and expanded capabilities for the GDP-based equipment line.
In 2007, Ken turned 71 and moved toward retirement, selling the Australian and Chilean subsidiaries and transferring the USA company to employee ownership under a new name, Zonge International. To mark his many notable accomplishments at this transition and to honor him personally, a special two-day seminar on IP and CR was organized at the 2007 SEG Annual Meeting. To our great loss, Ken Zonge passed away 21 November 2013. His family legacy includes his wife of 54 years, Kim; children Gene (electrical engineer), Tammy (fiscal operations manager), and Lynn (fluvial geo- morphologist); and three grandchildren.
Ken did not seek industry accolades, but they sought him: best presentation award, 1975 SEG Annual Meeting; 1995 SEG Enterprise Award; 2002 American Mining Hall of Fame Medal of Merit; 2002 SAGEEP meeting general chairman; 2005–2006 Small Business Administration’s Award for Ex- cellence; 2011 EEGS/SEG-NSG Frank Frischknecht Leader- ship Award; and more than 50 publications and numerous presentations.
It would be impressive enough if these accomplishments were the sole substance of Ken Zonge’s credentials, but that is hardly the case. They are matched by his legacy as a compas- sionate mentor and friend. Just by following him around for a day, you might learn more about applied science than in graduate school (some of us thought of him as “Zonge U”). He extended his mentorship to countless summer field-camp students at the University of Arizona by supplying equip- ment, field personnel, and free pizza. He also established the Zonge Scholarship under the SEG Foundation for graduate students for research and development in electrical methods and instrumentation and a similar fund at the University of Alaska, Fairbanks.
Ken displayed an understated compassion that seemed boundless — whether it was a teetotaler Ken cheering a dis- couraged employee with the gift of a first-growth Bordeaux (who can argue with the Rothschilds?) or a cash-strapped Ken floating an informal loan to an employee who found herself with more month than money or a time-crunched Ken ar- ranging tickets home for a bereaved international intern — his hand was an extension of his heart. The accountant always winced whenever Ken would conclude a phone call and walk her way with a concerned look on his face ... might as well pull out the checkbook.
These characteristics point to perhaps Ken’s quintes- sential quality. Most would agree that his strong suit was not business management, but he had leadership qualities no M.B.A. program could imbue. He had the ability to inspire, to make you better than you thought you could be individually, and to make a group far better than the sum of its members. If he pulled 60 kg of electrical cables in the Arizona heat without complaint, you did too. If he squat- ted over a receiver to monitor data somewhere deep in the Outback, you did too — no standing around idly swatting flies. When he took a critical second look at data or a pet theory, you learned the value of healthy skepticism. And watching him treat a competitor with civility, you learned a valued lesson in humanity.
These traits rubbed off. During the company’s financial crisis in the mid-1980s, a visibly pained Ken was forced to lay off the entire staff. The next Monday morning, a handful of employees turned into the gravel parking lot and went in to work as usual. Perplexed, Ken explained that he couldn’t pay them. Their reply was yes, fine, but we need to get these re- ports out, and maybe we could talk about details like money another time. The reports went out, the pay didn’t materialize for a long while, but the company recovered and eventually thrived. This outcome was the direct result of Ken’s inspiring leadership. It was a privilege to work for him. To have written this tribute in the past tense is somewhat misleading, for Ken still teaches us in the present tense. We think of his guiding example often as most of us hit the home stretch of our professional careers. Take risks and innovate. Work hard. Inspire others to be their best. Befriend those needing help. Be a mentor. Be humble in the face of both praise and criticism. Take our science and our professional responsibilities seriously. But never, ever take yourself so seriously that you think you’re above getting out there to sweep off the front porch.
Editor's note: The family requests that you honor Kenneth Zonge by mentoring, inspiring, or befriending someone in your personal or professional life. One practical way to do this is to contribute to SEG’s Kenneth L. Zonge Scholarship. Contact firstname.lastname@example.org for details.
IP Symposium 2007
Ken Zonge honored with special IP symposium Geophysicists interested in induced polarization, complex resistivity, and related techniques, as well as explorationists and friends who wish to honor Ken Zonge for his many contributions to geophysical exploration are invited to a special symposium on 27–28 September 2007 in San Antonio immediately following SEG’s 2007 Annual Meeting. This symposium coincides with Zonge’s transition to a less active role after 35 years as the founder and driving force behind Zonge Engineering, now one of the world’s leading firms in the design/development of electrical equipment for mineral exploration and engineering and environmental studies. SEG formally recognized this achievement in 1995 when Zonge received the Cecil Green Enterprise Award.
The symposium will feature invited talks by many leading researchers and practitioners. In addition, poster presentations of specific developments and applications have been invited. The technical program portion of the symposium, scheduled for Room 103A of the Henry B. Gonzalez Convention Center, will have morning and afternoon sessions on Thursday (27 September) and a morning session on Friday (28 September). An informal social event will be held Thursday evening. SEG has assisted in arranging this special symposium, but it is not part of SEG’s 2007 Annual Meeting. Consequently, separate registration and an additional fee are required. Delegates will be able to register at the Zonge Engineering booth, on the floor of the SEG exposition, or at the meeting room. The cost for onsite registration is US$85 (US$50 for students and retirees). The registration fee will cover a buffet lunch on Thursday. The Thursday evening social event will include hors d’oeuvres and a no-host bar.
Biography Citation for the SEG Cecil Green Enterprise Award 1995
Contributed by Jack Corbett
Geophysics in mining exploration focuses on electrical methods. Dr. Kenneth L. Zonge has been one of the leaders in the development of electrical prospecting techniques and technology. Under his leadership, Zonge Engineering and Research (not to be confused with or compared to the large geophysical R&D corporations in seismic methods) has quietly and steadily made a place for itself in the technical community through the design and development of electrical equipment for mineral exploration as well as in engineering and environmental sciences.
Kenneth's doctoral research and dissertation at the University of Arizona (1972) in complex resistivity was directed toward a means to identify specific minerals using electrical techniques. Zonge Engineering was formed shortly thereafter to continue this research approach with the intent of applying the techniques to field exploration. In the following years this on-going research in complex resistivity was widely reviewed and discussed. Although the particular approach to mineral discrimination was not then a commercially successful venture, the early work evolved into a new approach and practical field system for induced polarization surveys.
Another side benefit was the development of a relatively simple and practical solution to remove the spurious and contaminating effects of electromagnetic (EM) coupling, which arise from the geometry of the ordinary induced polarization (IP) measuring technique. Kenneth was one of the first to routinely decouple the IP response from the EM coupling effects.
In later years he expanded into other electrical exploration technologies. Kenneth was in the forefront of the development of the controlled source audiomagnetotelluric (CSAMT) technique and a strong proponent of its use for exploration of deeply buried targets.
Zonge Engineering and Research has grown from a small group of four dedicated individuals to over 60 full-time employees worldwide who handle equipment development, sales and service, and field applications. Over 12 field crews operate from offices in Tucson, Adelaide, Reno, Hermosillo, and Fairbanks (during the field season).
In 1978, the company initiated a complete line of transmitters, receivers, and peripheral equipment used for many types of electrical surveys. That integrated approach persists today. With advances in microprocessor technology, the latest receiver is a multichannel, multipurpose system with 32-bit microprocessor technology which can run resistivity/IP, CSAMT, TEM, AMT, and MT programs without internal hardware configuration changes.
This latest version, the GPD-32 receiver, is lighter, faster, ar;d more efficient than its predecessors and is a versatile, compact, sophisticated but utilitarian, digital acquisition system. Currently 200 of these systems are being used worldwide.
The primary activity of Zonge Engineering and Research has been related to mining exploration clients. A steadily growing segment is environmental science in which electrical mapping of subsurface structure and contamination plumes are important functions. And occasionally, specific but limited applications in hydrocarbon exploration are recognized.
In the many years I have known Ken, he has always been the epitome of a quiet, dedicated, hard-working scientist and engineer, and always a gentleman. Despite financial ups and downs, he has endured, and his company has flourished in selling to a demanding industry with its own internal drawbacks in budget and geophysical exploration program continuity.
These difficulties have not deterred Ken from maintaining his vision of an increasingly sophisticated and multipurpose electrical acquisition system for field use. His quiet leadership has persevered, and his company maintains a status in the vanguard of those in the manufacture and widespread use of electrical method systems that are considered by many to be the state of the art in the commercial world.
Ken is dedicated to his family and his work. He has served the mineral exploration and environmental science communities well, not only as a supplier of hardware but also as a source of technical information through both his publications and his willingness to share his expertise as an able and patient teacher.
If success is measured less by cash flow than by the amount of recognition and respect received from friends, colleagues, competitors and other exploration and enginering companies, then Zonge Engineering is indeed successful, and Ken himself is a giant in his chosen field.