The Leader of the Search for Illinois Dinosaurs by Steve Brusatte
A Portrait of Russ Jacobson
By Steve Brusatte
Since the discovery of the first wellknown specimens in England, dinosaur fossils have literally been found around the world. Remains of these denizens of the Mesozoic have been recovered from central China, the shores of Australia, limestone quarries near Rome, and even from a mountaintop in Antarctica. Every continent boasts several dinosaur specimens, foremost among them North America, which sports perhaps the world\'s bestknown dinosaur fauna.
Triassic, Jurassic, and Cretaceous rock layers outcrop across North America, many of which preserve exquisite specimens of dinosaurs. The majority of these fossils come from the American and Canadian west, although bones, teeth, and other signs of dinosaurian life are also found in the east. One American state that remains dinosaurpoor, however, is Illinois. One man, Russ Jacobson, is out to change that. At first glance, Russ Jacobson may seem an unlikely dinosaur paleontologist. Born in Hampton, Iowa, Jacobson received is Bachleor\'s Degree in Geology from the University of Northern Iowa in 1973. While studying at Northern Iowa, Jacobson was employed as a curator of the University\'s Museum. His duties included managing the geology exhibits and collections, and his work provided experience that would aid him in future endeavors.
Months after graduation from college Russ was hired by the Illinois State Geological Survey in Champaign, Illinois. He received the title of Research Assistant in the Coal Section, a position that would provide the basis for a career\'s worth of study. Jacobson held this job for four years, until 1977, when he was promoted to Assistant Geologist I of the Survey\'s Coal Section. Russ was promoted yet again in 1982, and around that time decided to return to college and pursue a Master\'s Degree in Geology. In 1985 he received his Master\'s from the University of Illinois, and in 1986 was promoted to Associate Geologist of the Coal Section. He held this position until 1999, when he became a full-fledged Coal Section geologist.
Only one year later, in July of 2000, Russ Jacobson was once again promoted, to the position of Acting Head of the Coal Section of the Illinois State Geological Survey. He continues to hold this position today.
His career as a coal geologist spanning four decades, Russ has held a plethora of duties during his tenure at the Survey. His work experience has included both research and administrative tasks, including educational outreach. He has led mapping teams, overseen budgets, developed energy resource plans, maintained collections and databases, and has worked with the United States Geological Survey in coal exploration.
He has also participated in his share of fieldwork and stratigraphic studies. Since his initial hiring in 1973, Russ has been interested in Pennsylvanian stratigraphy and depositional environments. As Illinois preserves one of the world\'s best known sequences of Pennsylvanian rock, including the world famous Mazon Creek biota, Russ has had many opportunities to pursue his interest in both the field and the laboratory. Along with other geologists from the Survey, he has led numerous fieldtrips to Pennsylvanian sites across Illinois, and has authored an important paper that correlated some of Central Illinois\' Upper Pennsylvanian limestone layers.
In addition to his work on the Pennsylvanian, Russ has been mapping Mississippian rock units since 1985 and has participated in extensive mapping projects in southern and western Illinois. While he is not in the field, Russ often gives fossil related talks and lectures to schoolchildren, leads teacher workshops, and organizes fossil collecting excursions.
Although Russ Jacobson has endured a successful career researching coal and Paleozoic rocks, perhaps his most impressive contributions have come in Mesozoic paleontology. Since 1995 he has been leading field studies of the Cretaceous McNairy and Baylis Formations in southern and western Illinois, and since 1987 he has been participating in dinosaur excavations in Wyoming, South Dakota, and Montana. Russ has done extensive work in the Morrison Formation of Wyoming, including excavations of fossils in the Bighorn Basin and near the town of Sundance. He has also excavated in the White River Formation of South Dakota and the Pierre Shale of South Dakota. Foremost among his discoveries in the Pierre Shale was a mosasaur, which was excavated near the city of Chamberlain.
During much of the 1990\'s, Russ led a field program in the Hell Creek Formation of South Dakota. Discoveries included fossils of many dinosaurs, including hadrosaurs, pachycephalosaurs, ankylosaurs, and theropods.
The most impressive finds included a pachycephalosaur skull, a nodosaur skull, tyrannosaur teeth and postcranial material, and the complete skull of a Triceratops individual. Found among these specimens were also fossils of crocodiles, turtles, amphibians, and fish.
In the summer of 2000, Russ developed a field tour for college students in association with the Utah Field House of Natural History in Vernal, Utah. Working with vertebrate paleontologist Dr. Steve Sroka, also a graduate of the University of Illinois, Russ did reconnaissance work at several sites inside the Salt Wash Member of the Late Jurassic Morrison Formation. He also had the opportunity to examine Triassic, Jurassic, and Cretaceous rocks in other parts of the state, and discovered a wide variety of vertebrate fossils and trackways.
As a result of Russ and Steve\'s work in 2000, a cooperative program, developed in partnership between Dinosaur National Monument, the Bureau of Land Management, and the Utah Field House of Natural History, was created. One year later, during the summer of 2001, the program hosted a volunteer crew that examined a wide variety of Mesozoic fossil sites. Included among these forays were trips to the Lower Cretaceous Cedar Mountain Formation, where new sauropod material was discovered, and the Salt Wash Member, where several new dinosaur and vertebrate specimens were excavated. In the summer of 2002 Russ will continue working with the cooperative program, when he, along with Illinois State Geological Survey geologist Joe Devera and Southern Illinois University chancellor Jim Staub, will lead a trip entitled \"Dinosaur Geology of the Colorado Plateau and Uinta Basin.\" This week long trip, offered through Southern Illinois University, offers students an introduction to the geology and paleontology of the \"Dinosaur Diamond,\" an area rich in Mesozoic rocks in Colorado and Utah. Joining Russ and his co-leaders will be Dr. Sroka, Dr. Sue Ann Bilbey, also from the Utah Field House, and Southern Illinois geologist John Utgaard.
With this inaugural trip planned for the summer of 2002, Russ hopes that the cooperative program will take off and lead to a permanent partnership between himself and many of the various museums and agencies in the western United States. However, with his increased work out west, Russ has not forgotten perhaps his greatest quest: to find the first dinosaur in the state of Illinois.
Despite Illinois\' large population and abundance of academic and scientific institutions, no dinosaur fossil has ever been found in the state. The reasons for this glaring lack are quite simple: since the dawn of the Permian, some 280 million years ago, most of Illinois has been entirely above land. While dinosaurs most likely lived on the land that now makes up the state, the lack of large river systems or seas made fossilization difficult. To complicate matters, Triassic and Jurassic rocks were either never deposited or have been completely eroded. There is one small hope, however, and Russ Jacobson is out to transform this glimmer of hope into one of the most important scientific discoveries in Illinois\' history.
During the Late Cretaceous most of Illinois was above sea level. However, two small areas of the state were covered by water. One such area, located on the extreme western tip of Illinois, was periodically covered by the Western Interior Seaway, the long waterway that divided the continent of North America in half during much of the Cretaceous. Another area, located in extreme southern Illinois, was once part of the Mississippi Embayment, the northernmost reach of the ancestral Gulf of Mexico.
The waterways that covered both areas left rock layers, but in each case finding fossils has been exceedingly difficult.
Many of the best units have been eroded away, and those that remain are often covered by commercial development or vegetation, basically nullifying the effects of natural erosion that frequently exposes fossils. Finding dinosaur bones in Illinois, while possible, is no easy task, but Russ Jacobson is not about to give up. What makes Russ so optimistic is that dinosaur specimens have been found in correlated beds just miles from the Illinois border, across the Mississippi River in Missouri.
At the Chronister Dinosaur Site near Cape Girardeau, Missouri, researchers have found a slew of dinosaur bones. More than half a century ago, in 1942, the Chronister family of rural Missouri uncovered a cache of enigmatic bones while digging a well.
A geologist who examined the bones recommended that they be sent to the Smithsonian Institution, where paleontologist Charles Gilmore eventually determined that some of the specimens represented the caudal vertebrae of a large dinosaur. Unfortunately, for paleontology, Gilmore died a short time after his examination of the bones, and the specimens were stored away and nearly forgotten. Luckily, in the 1950\'s, geologist Bruce Stinchcomb read Gilmore\'s paper describing the specimens and became interested in the site. It was two decades later, in the late 1970\'s, when Stinchcomb finally got around to visiting the dinosaur-producing well.
Upon arrival, he discovered that the landowner, the youngest son of the Chronister family, was willing to put the land up for sale. Stinchchomb, with funding from the St. Louis Academy of Science, agreed to purchase the land, and exploratory excavations began. Before long a wide variety of dinosaur bones was found, and in 1999 the Missouri Ozark Dinosaur Project was launched. The Project, led by paleontologist Guy Darrough, continues to uncover excellent, although fragmentary, specimens. Excavations at the site confirmed that the bones were found in a rock layer correlated with the McNairy Formation, a unit that outcrops in Illinois. This has led Russ to speculate that perhaps some of the same dinosaurs found in Missouri, among them hadrosaurs, tyrannosaurs, and ornithomimosaurs, may also be found in Illinois.
Because of this strong possibility, Russ, Joe Devera, and scientists from Southern Illinois University have been participating in field work and reconnaissance studies for several years.
Although no vertebrate material has yet been found, the fact that vertebrate fossils were recently found in a 64-million-year-old Paleocene rock unit in southern Illinois has yielded optimism. Will dinosaurs ever be found in Illinois? Russ Jacobson thinks so. While he believes that the ongoing study and excavation of Late Cretaceous rock layers is necessary, Russ feels that the first dinosaur bones from Illinois may be located much like they were in Missouri: through some fortuitous turn of events when someone stumbles on a fresh exposure of rock or an unknown stream bank.
As the aforementioned scenario is a strong possibility, Russ advises anyone who stumbles across a possible vertebrate specimen contact him at the Illinois State Geological Survey before removing any specimens. Until that day comes, however, Illinois will remain dinosaur-less. Russ Jacobson is out to change that. Although his work has included forays into coal research, Pennsylvanian stratigraphy, and Mississippian fossils, Russ\' true love is dinosaurs. Hopefully, in the near future, he will secure a dinosaur specimen for his home state
Jacobson, R. J., 1998, The Quest For Dinosaurs in Illinois, in: Dinosaur World, Summer-Fall 1998, No. 5, ISSN 1091-3661, pages 17-19
Jacobson, R. J., and Sroka, Steven D., 1998, Preliminary Assessment Of A Hell Creek Dinosaurian Fauna From Sites In Corson County South Dakota, Journal of Vertebrate Paleontology, Volume 18, Supplement to Number 3, 13th September, 1998, Abstracts of Papers, 58th Annual Meeting, Society of Vertebrate Paleontology, Snowbird Ski and Summer Resort, Snowbird, Utah, page 53A.
W.T. Frankie, R. J. Jacobson, Masters, J.M., Rorick, N.L., Admiraal, A.K., Jeffords, M.R.,Post, S.M., Phillips, M.A., Jones, E., 1997, GUIDE TO THE GEOLOGY OF THE MISSISSIPPI EMBAYMENT AREA, JOHNSON AND PULASKI COUNTIES, ILLINOIS, ISGS
Field Trip Gudebook 1997D, November 1, 1997
R.S. Nelson, D.H. Malone, R.J. Jacobson, and W.T. Frankie, 1996, GUIDE TO THE GEOLOGY OF THE BUFFALO ROCK, AND
MATTHIESSEN STATE PARKS AREA, LA SALLE COUNTY, ILLINOIS, ISGS Field Trip Guidebook 1996C AND 1997B, September
28, 1996 and May 17, 1997.
Sroka, S.D, and Jacobson, R. J., 1992, A comparison of faunal assemblages and lithologies of the Francis Creek Shale Member (Carbondale Formation) in western and northeastern Illinois, Geological Society of America, Abstracts with Programs, vol. 24, no. 7.
Jacobson, R. J., 1985, Coal resources of Grundy, LaSalle, and Livingston Counties. Illinois State Geological Survey, Circular 536, 58 p.
Jacobson, R. J., C. B. Trask, C. H. Ault, D. P. Carr, H. H. Gray, W. Hasenmueller, D. A.Williams, and A. D. Williamson, 1985, Unifying nomenclature in the Pennsylvanian System of the Illinois Basin: Transactions of the Illinois Academy of Science, vol. 78, nos. 1-2, p. 1-11. (ISGS, Reprint 1985K)
Treworgy, C. G., and R. J. Jacobson, 1985, Paleoenvironments and distribution of lowsulfur coal in Illinois: in Cross, A. T., ed.,
Economic Geology: Coal, Oil and Gas; Compte Rendu, vol. 4. Ninth International Congress of Carboniferous Stratigraphy and
Geology, Urbana, Illinois, 1979. p. 349-359 (ISGS Reprint 1986E)
Jacobson, R. J., 1983, Revised correlation of the Shoal Creek and LaSalle Limestone Members of the Bond Formation (Pennsylvanian) in northern Illinois. Geologic Note: Illinois State Geological Survey, Circular 529, p. 1-6, 1 plate