The Advanced Chemistry Basins Project: Final Report

In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain maturity indicator and maturation kinetic data set, an oil chemistry and flash calculation tool operable under Excel, and a user friendly, graphically intuitive basin model that uses this data and flash tool, operates on a PC, and simulates hydrocarbon generation and migration and the chemical changes that can occur during migration (such as phase separation and gas washing). The DOE Advanced Chemistry Basin Model includes a number of new methods that represent advances over current technology. The model is built around the concept of handling arbitrarily detailed chemical composition of fluids in a robust finite-element 2-D grid. There are three themes on which the model focuses: chemical kinetic and equilibrium reaction parameters, chemical phase equilibrium, and physical flow through porous media. The chemical kinetic scheme includes thermal indicators including vitrinite, sterane ratios, hopane ratios, and diamonoids; and a user-modifiable reaction network for primary and secondary maturation. Also provided is a database of type-specific kerogen maturation schemes. The phase equilibrium scheme includes modules for primary and secondary migration, multi-phase equilibrium (flash) calculations, and viscosity predictions

Advanced Chemistry Basins Model

The advanced Chemistry Basin Model project has been operative for 48 months. During this period, about half the project tasks are on projected schedule. On average the project is somewhat behind schedule (90%). Unanticipated issues are causing model integration to take longer then scheduled, delaying final debugging and manual development. It is anticipated that a short extension will be required to fulfill all contract obligations

Engineering: Cornell Quarterly, Vol.25, No.1 (Autumn 1990): Water in the Ground

IN THIS ISSUE: Mathematical Models of Nonpoint-Source Pollution /2 Douglas A. Haith ... Preferential Flow in Structured and Sandy Soils /7 Tammo S. Steenhuis and J.-Yves Parlange ... Finding Layers in the Soil: Ground-Penetrating Radar as a Tool in Studies of Groundwater Contamination /15 Tammo S. Steenhuis, K.-J. Samuel Kung, and Lawrence M. Cathles, III ... Composting and Water Quality /20 Tom Richard ... Removing Toxic Organics from Groundwater: Biological Conversion of PCE and TCEI /25 William J. Jewell ... Register /30 ... Faculty Publications /37 ... Editorial /4

Engineering: Cornell Quarterly, Vol.27, No.3/4 (Spring/Summer 1993): Probing Earth's Processes

IN THIS ISSUE: Probing Earth's Processes /2 (Cornell geologists travel far and wide, interpreting subtle clues to learn how the earth works.) ... Mountains, Climate, and Global Change /3 (Mountain ranges affect weather and weather affects mountain ranges in a cycle that produces the soil that sustains life.) ... The Cornell Andes Project: An Interdisciplinary Study of Mountain Building /9 (A major initiative studies the world's best example of a mountain chain pushed up by subducted oceanic crust.) ... Deep Seismic Exploration in Tibet /12 (A collaboration with Chinese geologists is making the first deep seismic transect of the Himalayas.) ... Earthquakes and Oil: Collaborative Research in the Arab World /17 (Studies involving geologists in North Africa and the Middle East lead to better assessments of earthquake hazards.) ... Geological Fieldwork in the Space Age /20 (In the wilds of Alaska, graduate students learn about geology and about themselves.) ... New Meeting Grounds: Collaborative Research in the Urals and Kamchatka /25 (In the wake of the Cold War, international teams study Asia's eastern and western extremes.) ... New Frontiers Close to Home: North America's Central Corridor /27 (Under the flat expanse between the Appalachians and the Rockies lie the remains of former mountains and rifts.) ...Deep-Focus Earthquakes /32 (Laboratory experiments give clues to processes deep in the earth's mantle.) ... Mantle Plumes and Oceanic Volcanism /34 (Independent of plate tectonics, mantle plumes create chains of islands.) ... Fractals in Geology /40 (Drainage systems and other geological phenomena can be modeled with fractals.) ... Register /42 ... Faculty Publications /4

Lower-mantle viscosity constrained by seismicity around deglaciated regions

KNOWLEDGE of the viscosity structure of the Earth's mantle is important for constraining models of mantle convection and isostatic rebound. Here we show that seismicity around the margins of deglaciated areas provides a constraint on the viscosity of the lower mantle, in addition to those previously proposed1,2. Calculations using a spherical, viscoelastic Earth model show that the present-day magnitude of the stress fields induced in the lithosphere beneath the (now-disappeared) Laurentide and Fennoscandian ice sheets is very sensitive to the value of the lower-mantle viscosity. Stresses of ∼100 bar, sufficient to cause seismicity, can still remain in the lithosphere for lower-mantle viscosities greater than ∼1022 Pa s; for lower-mantle viscosities of ∼1021 Pa s, only a few tens of bars of stress persist in the lithosphere today. This influence of lower-mantle viscosity on the state of stress in the lithosphere also has implications for the migration of stress from earthquakes, and hence for earthquake recurrence times. © 1991 Nature Publishing Group