Course Outline

Learning How to Learn and Think:Geologic Reasoning Concept Mapping Workshop

Beijing Normal UniversitySeptember 11-22, 2017

Kip Ault (山水 Shan Shui), Ph.D., Professor Emeritus ault@lclark.edu Lewis & Clark Graduate School of Education and Counseling

Portland, Oregon, USAwww.darwinianwhimsy.com

Aims:

Meaningful learning requires making connections among concepts and from concepts to experiences. When structured around core concepts, these connections lead to disciplinary expertise and insight.

Habits of mind characteristic of different disciplines develop in response to distinct challenges. As a result the structures of knowledge differ from one field to another. Concept mapping and Vee diagramming promise to bring such structures into focus, making learning efficient. (Concept maps are drawings that depict networks of relationships and hierarchy among concepts. Vee diagrams deploy concept maps in order to represent the structure of knowledge in the context of an inquiry.)

Geologic reasoning responds to challenges of scale and the contingent nature of historical phenomena. Often analogical approaches—comparison and contrast—play an important role in geologic inquiry.

Comparing one place to another, in terms of its geologic history and climate pattern, for example, has the potential to illuminate the “big picture” while fostering a “deep love” for knowledge. Geologic inquiry often depends on finding modern analogues for historical processes.

Plate tectonics theory and the geologic time scale are two “big ideas” essential to organizing meaningful understanding of geology. The former can be illustrated with attention to the patterns and processes characteristic of plate boundaries and collisions. The interpretation of the Grand Canyon of the Colorado River reveals the power of insight into deep time. Comparison and contrast of the geologic history of the Tibetan and Colorado Plateaus. understood in terms of plate tectonics, reveals principles for interpreting earth’s dynamic landscapes.

The Earth system—the atmosphere and oceans, the icecaps and glaciers, the soil and vegetation, and the animals and insects—is a complex, interacting system with both strong and delicate

feedbacks that govern the climate and the habitability of our planet.--Ian Roulstone & John Norbury, Invisible in the Storm (Princeton: 2010), pp.44-45

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1. Schedule of Classes:

Day 1: “Principles for Thinking Geologic Thoughts.” ppt. 001. In class activity: aerosol spray, ice cube buoyancy, musical straw instrument.

Assignment 1: Vee Diagram with Concept map of class exercise. Due Day #2.

>> Begin reading (and sharing copies of) Peter Molnar’s Plate Tectonics, A Very Short Introduction. Complete the reading of this book before Class #4.

PAGES to READ in Molnar’s book: Basic History 1-16 Seafloor Spreading 17-20; 32-35(none of Chapter 3) Subduction and Volcanoes 53-63; 73-76 Rigid Plates

77-83Tectonics of Continents 89-109 Whence to Whither (past to future) 110-117

Read for the next class:

McClaughry, et al., Field Trip Guide to the Oligocene Crooked River Caldera: Central Oregon’s Supervolcano (2009). Oregon Geology, 69, 1.

Ault, C. R., Jr. (2017). Thinking Geologic Thoughts: Interpreting Traces of Past Events. Proceedings of the 1st Asian Pacific Conference on Concept Mapping, September 20-22, Beijing Normal University, Beijing, China.

Ault, C. Review of The Orphan Tsunami of 1700. (2006). Prepared for the University of Washington Press. Find the full report by Brian Atwater, et al., at:You can read the entire paper (and view its beautiful illustrations) athttps://pubs.er.usgs.gov/publication/pp1707

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Day 2: Cascadia’s Ghost Forests: Thinking and doing in the earth sciences using analogy, place, and time; ppt. 002 “Ghost Forests of Cascadia.”

NEXT CLASS: MEET IN THE LOBBY OF THE JINGSHI HOTEL.

Assignment 2: Concept map in answer to the focus question, “What caused the Pacific NW Ghost Forests?” Include in the map at least two of the 8 Principles from “Thinking Geologic Thoughts” (Ault, 2016, CMC Proceedings paper above). Due Day # 4. Recommended principles to include: resolving puzzling anomalies with common cause and time as a referee.

Read for the next class:

Fillmore, R. (2011), The Tertiary Period: The Rise of the Colorado Plateau, Geological Evolution of the Colorado Plateau of Eastern Utah and Western Colorado.

Day 3: Colorado Plateau and plate tectonics, ppt. 003, “Colorado Plateau and Plate Tectonics,” ppt. 003b, “Colorado Plateau Blakely.” Work on “Ghost Forest” concept maps. Begin “Colorado Plateau/River” concept map “Parking Lot.”

Assignment 3: Concept map in answer to your own focus question about how the Colorado Plateau (Fillmore chapter) or the Colorado River (Pederson article) may have formed. Include in your map at least one principle from Ault’s “Thinking Geologic Thoughts.” Recommended principle to include: using modern analogues. Due Day #4.

Read for the next class:

Pederson, J. L. (2007). The Mystery of the Pre–Grand Canyon Colorado River—Results from the Muddy Creek Formation: GSA Today, v. 183, p. 4-10. doi: 10.1130/GSAT01803A.

Day 4: Rock walk at the Jingshi Hotel. MEET IN THE HOTEL LOBBY. Back to the classroom for identification of the Rock PicturesCookie Aesthenosphere and Pie PlatesHow do we know? (discussion)Ghost Forest maps/vee diagrams.Colorado Plateau Models review and how “Old” is the Grand Canyon of the Colorado River? (ppt. 003 continued).Seeing through time: Blakey’s reconstructions of the Colorado Plateau (ppt. 003b).Questions about Peter Molnar’s Plate Tectonics: A Very Short Introduction? (terrane, craton). Pay close attention to Chapter 6: “Tectonics of Continents.”Work on Colorado Plateau maps/vee diagrams.

Assignment 4: Revise and improve Ghost Forest and Colorado Plateau/River maps with concepts from Peter Molnar’s Plate Tectonics, A Very Short Introduction. See if any more ideas from Ault’s “Thinking Geologic Thoughts” can be added as well. Due Day #5.

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Read for the next class:

Molnar and Tapponnier (1977). The Collision between India and Eurasia. Scientific American, 236 (4), pp. 30-40.

Searle, M. (2013). Roof of the World in Colliding Continents.Searle, M. (2013). The Making of the Himalaya/Tibetan Plateau in Colliding Continents.Harrison, M.T., Copeland, P., Kidd, W. S. F., & Yin, An. (1991). Raising Tibet, Science 255,

1663-170. New York Times, “A Quake-Causing Collision Course,” New York Times, May 19, 2015, p.

D5.Li, et al., (2016). Paleomagnetic Constraints on Mesozoic Drift of the Lhasa Terrane (Tibet)

from Gondwana to Eurasia. Geology, 44 (9), pp.727-737.

Day 5: The Tibetan Plateau; ppt. 005 “Colliding Continents and Plate Driven Tectonics,” and ppt. 005b, “Tibetan Plateau Blakey.” Sharing “Ghost Forest” and “Colorado Plateau” maps to critique the addition of concepts from Molnar’s Plate Tectonics.

Assignment 5: Concept map (not a vee diagram, just a map!) of Plate Tectonics including principles of geologic thinking as an explanatory framework and applied to examples of plate margins you have learned about in class. Build upon your Ghost Forest and Colorado Plateau work. Add the story of Tibet if you wish. Present these maps in class #6. Due Day #6.

Read for the next class:

Valley, J. W. (2005). A Cool Early Earth? Scientific American. 293 (4), pp. 58-65.Ruddiman, W.F., & Kutzbach, J.E. (1991). Plateau Uplift and Climatic Change: The

formation of giant plateaus in Tibet and the American West may explain why the earth’s climate has grown markedly cooler and more regionally diverse in the past 40 million years. Scientific American, 264(3), 66-75.

Garzione, Carmala N. (2008). Surface uplift of Tibet and Cenozoic Global Cooling. Geology, 36(12), 1003-1004.doi: 10.1130/focus122008.1

Raymo, M.E., & Ruddiman, W.F. (1992). Tectonic forcing of late Cenozoic Climate. Nature, 359(6391), 117-122.

Day 6: The Tibetan and Colorado Plateaus: geology in relation to climate. “Climate Change and Plateau Uplift,” ppt. 006; time permitting: ppt. 009 “Grand Canyon and the Trail of Time.”

Presentations of Plate Tectonics and geologic thinking concept maps with examples from the Cascadian Subduction Zone (Ghost Forest) Colorado Plateau (Grand Canyon of the Colorado River), the Collision of India and Asia (Tibetan Plateau, Himalayas).

There is no written component to submit together with your final cmap for the geology module.

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Reflective Writing: What have you learned about learning and thinking in the 2 modules?

2. Prerequisites:

English proficiency.Familiarity with geologic or geographic concepts at an introductory level.Willingness to study original research in an unfamiliar discipline.Curiosity about how landscapes form.

Concept Maps from Ault, 2016, “Thinking Geologic Thoughts,” CMC BNU Conference:

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Powerpoint resources:

ppt. 001, “Principles for Thinking Geologic Thoughts”ppt. 002 “Ghost Forests of Cascadia” ppt. 003, “Colorado Plateau and Plate Tectonics”ppt. 005 “Colliding Continents and Plate Driven Tectonicsppt. 006 “Climate Change and Plateau Upliftppt. 009 “Grand Canyon and the Trail of Time

Supporting References:

Blakey, Ron, & Ranney, Wayne. 2008. Ancient Landscapes of the Colorado Plateau. Grand Canyon, AZ: Grand Canyon Association.

Kearey, P. Klepeis, K. A., and Vine, F. J. 2009. Global Tectonics. West Sussex: Wiley-Blackwell.

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Nie, J., Horton, B. K., and Hoke, G. D., Eds. 2014. Toward an Improved Understanding of Uplift Mechanisms and the Elevation History of the Tibetan Plateau (GSA Special Paper No. 507). Boulder, CO: Geological Society of America.

Searle, M. 2013. Colliding continents: A geological exploration of the Himalaya, Karakoram, and Tibet. Oxford University Press: Oxford, UK.

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The Challenge of Geologic Inquiry:An Overview of How Geoscientists Interpret the Earth

Kip AultJune 29, 2017

Knowledge is not absolute, but rather it is dependent upon the concepts, theories, and methodologies by which we view the world.

–D. Bob Gowin & Marino C. Alvarez, The Art of Educating with V Diagrams (2005)

Geologic inquiry depends upon concepts and practices responsive to the challenge of interpreting the earth—to connecting the patterns of its landscapes and structures to the processes that formed them. Dynamic interactions encompassing both physical and living systems span the vastness of geologic time and occur from micro to macro scales in time and place. Understanding “scale” is crucial to geology as a way of knowing. Geologic problems cross many scales and at each scale solutions may differ. Yet these solutions must cohere—the explanation patterns of crystal formation must not contradict the account of regional crustal movements, for example, when interpreting a particular place on earth. The present contains remnants of the past distributed as confusing puzzles. Geoscientists strive to solve these puzzles with methods of inquiry adapted to this end. Often unable to execute experimental methods, geologic inquiry –D. stands as emblematic of diversity among scientific ways of knowing.

Geology values comparing ancient landscapes to modern analogs, substituting place for time, determining temporal relationships, and entertaining multiple working hypotheses. Confidence in geologic solutions increases when independent lines of evidence converge on the same explanation and solutions to problems on different scales cohere. Temporal reasoning permeates the task of interpreting the earth’s history and structure. Many of the important concepts in geology encapsulate a time series: its key words imply stories. Consider “eruption” and “erosion” for example. Each of these concepts refers to a process that unfolds in time.

Geologic rhetoric is temporal rhetoric. Eruption and erosion happen as a sequence of events.

Disciplinary practices diversify as they respond appropriately to the nature of different challenges, such as time’s vastness. In geological inquiry, place by place comparisons converge on past causes and future risks, an approach irreducible to single variable manipulation in a controlled experiment. When traces of past events carefully sequenced and synchronized create a set of anomalous associations across time and place, a geologist seeks a common cause rendering these anomalous associations plausible.

Geoscientists often represent temporal relationships visually, depicting data in forms that promote spatial reasoning. Geologic maps are the perfect—and stunningly attractive—example. They color time.

Good geologic reasoning depends upon making comparisons in terms of carefully restrained, yet ultimately ambiguous, categories. The reason is simple: every feature of the earth has a history. All “deltas” are similar to each other and at the same time each one is unique. The same observation applies to “mountains” and “faults” and even “crustal plates.” These are the objects of interest in geology. Productive comparisons among deltas and between deltas and

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seafloor fans yield insights into the processes that formed them—and inferring processes from patterns is the goal of geologic inquiry. In contrast, individual atoms of carbon 12 are utterly indistinguishable and completely interchangeable. A carbon atom does not come wrapped in the history of its past interactions; the Grand Canyon of the Colorado River does. How this river may have exited the Colorado Plateau has fueled contentious debate for many years. Perhaps for a time the river simply faded away without reaching the ocean. Some propose that the Colorado infiltrated Paleozoic limestones beneath its riverbed, dissolved masses of carbonate rock, and emerged in desert springs only to evaporate, re-depositing volumes of limestone. Comparison to how major rivers terminate in China’s Tarim Basin and Angola’s Kalahari Desert give credence to this interpretation of one of the earth’s most striking and dynamic features.

Through this mini-course, as you learn to depict your understanding of geologic phenomena with concept maps, your grasp of geologic inquiry will grow. Keep in mind the important match between conceptions of geologic phenomena to practices characteristic of geologic inquiry. The match responds to the distinctive challenge of time’s vastness.

Keep in mind that developing a sense of scale is a distinctive feature of learning geoscience. The concept of scale functions both psychologically and epistemologically. Psychologically, scale may present obstacles to perception and insight. Epistemologically, extrapolation of earth processes in time and space is a goal of explanation. The geologic time scale encompasses durations and changes vastly beyond the scale of human lifetimes; forecasts of global climate change must wrestle with problems of sampling and modeling on various scales.

Geologic thinking may be fruitfully characterized as being guided by several disciplinary distinctive principles such as (Ault, 2017):

1. Place for Time. Place substitutes for time and the present is a sampling distribution of differently scaled processes. Darwin, for example puzzled over volcanic atolls he encountered when sailing cross the Pacific. There were atolls with fringing reefs, islands encircled by shallow lagoons, and volcanic islands, both active and inactive. Darwin concluded that these islands represented different stages of a very long process. He proposed a sequence of initial eruption, coral growth at crucial depths, and subsidence leaving a lagoon (Darwin, 1843). One island was an example of another’s past and yet another the harbinger of its future. Present time offered a sampling distribution of stages in this process spanning an immense period of time. Substituting place for time made the problem tractable and overcame the challenge of scale. In geologic thinking place often substitutes for time in order to arrange landscapes in the present as representative of a series of stages and thus achieve an understanding of their histories. Dating of the stages must be independent of the arrangement.

2. Singular Entities. “Singular” applies to statements about the past and to categories for making comparisons and contrasts. The salient properties of the phenomena of interest in geologic inquiry are contingent on their history. As a consequence, basic geologic categories are fluid. Members of a category resemble each other in important respects and differ from each other in many others. For example, large rivers deposit sediments at their mouths, often forming “deltas.” The category “delta” includes many examples, but its members are not interchangeable parts. Some are birds-foot deltas; some are triangular. Categories constructed for reasoning by comparison and contrast of singular entities are therefore fluid or even “necessarily ambiguous” (Author, 1998). The opposite

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is true for the fundamental entities in physical science disciplines such as chemistry; consider “carbon.” To the chemist, carbon atoms and isotopes are interchangeable, and the properties of a carbon atom are independent of its history. The history of events in which a particular atom of carbon-12 has participated is not relevant to carbon chemistry, and an atom of carbon does have traces of its history. Perhaps it decomposed from an oak tree leaf, escaped from the soil into the atmosphere as gaseous carbon dioxide, became part of a carbonate skeleton, settled to the sea floor, plunged beneath the margin of North American, and, 500,000 years later erupted in an episode of Cascade Arc volcanism. Each stage through which the imaginary atom of carbon-12 has passed is a singular event—no volcanic eruption is exactly the same as another. The series of events constitutes a process—the carbon cycle—that varies from place to place and epoch to epoch in important respects. If it did not, global warming would not be an issue. What matters about carbon matters equally, no matter where and when in space and time. In contrast, geologic phenomena of interest form and dissipate through time, the future always contingent upon the past. Geologic claims are about particular events and are, by nature, probabilistic, genetic, and “sketchy” (Kitts, 1977, p. 25). In brief, the most “characteristic demand” of geological problem-solving is the concern for singular, not universal, statements, characterized by phrases such as “tends to, distinctive of, resembles, typically, distinct from,” and “in contrast to” (Kitts, 1977, p. 35).

3. Coherence across Scales. Different problems exist on different scales. Confidence in solutions grows when they cohere (or at least do not contradict each other) from one scale to another. The most remarkable example of this principle is the claim of the impact of an extraterrestrial object bringing about the extinction of the dinosaurs and the end of the Cretaceous Period. From crystalline microscale to global phenomena, problems in geophysics, geochemistry, minerology, distribution of geologic objects (crater, clay strata, fossils, traces of iridium), and timing all line up to support the “Alvarez hypothesis” of an immense impact dismantling the Cretaceous world (Powell, 1998). Solutions to problems on different scales must, at a minimum, not contradict each other. When they cohere in time and space, confidence in claims increases. Variability exists on different scales as well. In a circular fashion, sampling helps to gauge the scale of variation so that data collection may adequately encompass the range phenomena of interest may occupy. For example, sediment flow in a stream varies seasonally and rare (once a millennium) events may move more sediment than transported in an average year (Schumm, 1991).

4. Modern Analogues. Analogy is the basis of comparison and modern analogues help to interpret past events. For example, vast beds of Paleozoic limestone (Mississippian age) exist on the Colorado Plateau. Off the Plateau, in an arid basin of Utah, more modern carbonate deposits are well known. Might these have been left by a proto-Colorado River, laden with dissolved ancient carbonate? Consider the observation that the age of evaporite and carbonate spring deposits near Lake Mead in Nevada coincides with the expected timing for a pre–Colorado River’s exit from the Colorado Plateau (Pederson, 2008). Where did the water and minerals found in these deposits come from? Do they indicate how the Grand Canyon became so deep? By Miocene time, a pre–Colorado River flowed westward, but how it may have exited the Colorado Plateau has fueled contentious debate for many years. Do the mineral deposits near Lake Meade suggest an

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answer? Perhaps for a time the river simply faded away without reaching the ocean. Joel Pederson and his research team suggest that the precursor of the modern Colorado River may have infiltrated Paleozoic limestones beneath the riverbed, dissolved masses of carbonate rock, and emerged in desert springs only to evaporate, redepositing volumes of limestone. Running underground may even have steepened the drainage gradient in the Grand Canyon and thus extended surface drainage upriver to capture other drainage basins as the hollowed out topography collapsed from below. Such a process occurs today in the Tarim Basin on the Tibetan Plateau—a possible modern analog to a crucial stage in the formation of the Grand Canyon (Pederson, 2008).

5. Story Form. The Earth is a text to interpret in a Hermeneutic fashion (Frodeman, 2003): context gives meaning to the part; parts give meaning to the whole; for example, the idea of crustal plates prompts new interpretation of prior facts; new facts prompt revision about crustal structures and processes. The meaning of a sentence depends upon the meaning of its words. In turn, the precise meaning of the words depends upon their context in a sentence. So it goes from one level to the next: sentence, paragraph, story, socio-historical context of the story. Minerals in the rock signify meaning; the exposure of an outcrop is their “paragraph” and the landscape a “story” to be told—one that may well lead to reinterpretation of the outcrop. Oregon’s Smith Rocks State Park has attracted rock climbers for decades. Lovely walls of volcanic tuff bake in the sunshine of the High Desert. By association with nearby beds of volcanic ash and by analogy to the present day range of Cascade volcanoes (which includes Mt. Hood and Mt. St. Helens), these tuffs were interpreted for several decades as the ash fall from arc volcanoes whose eruptive centers lay buried beneath more recent eruptive activity. Then a stunning new interpretation of the regional geology of the Crooked River Basin overturned this interpretation. The Tuffs of Smith Rock signified caldera scale eruptions from 45 million years ago (McClaughry, Caroline L. Gordon, and Mark L. Ferns, 2009). This interpretation put them in the context of the narration of collision history between the North American and the Pacific tectonic plates in a dramatically new way. Instead of the result of arc volcano eruptions paralleling a subduction zone trench, the Smith Rock tuffs were fragments—traces of the past—of a vast crater left behind by the piercing of continental crust by a mantle plume. Their reinterpretation placed them in company with the trace of a hot spot leading across Idaho to Yellowstone country. Many of the words remain, but the story has changed.

6. Puzzling Anomalies. Puzzling associations may have a common cause; the common cause simultaneously resolves anomalies on different scales; lines of evidence leading to the common cause are independent of each other. Philosopher Carol Cleland (2011) has popularized this principle and attributes to it success in establishing causation in geologic inquiry. This principle applies to Darwin’s atoll hypothesis (common cause of the puzzling association of islands, volcanoes, and coral reefs) and to Alvarez’ Cretaceous extraterrestrial impact idea. Brian Atwater’s discovery of the history of subduction zone earthquakes in the Pacific Northwest stands as one of the most stunning examples of resolving puzzling anomalies. His work integrated bureaucratic records from imperial Japan, Native American oral histories, the distribution of ghost forests (trees killed by sudden subsidence and seawater inundation) along coastal Oregon and Washington, and buried mudflat deposits over a wide region (Atwater, 2005). Independent of Atwater’s

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research hypothesizing an earthquake in the Pacific Northwest dated to the year 1700 by tree rings)—and coincident with records in Japan of a tsunami at the same time—marine geologists established widespread turbidites (massive underwater landslides) off the continental shelf synchronized with the 1700 date. Subsequent turbidite measurements established a chronology of subduction zone earthquakes in the region (Goldfinger, et al., 2012).

7. Temporal Visualization. Geologic data yield visual representations of temporal and spatial relationships; geologic maps are the best example. Visualization works hand in hand with every other principle, of course, and all of these representations make temporal relationships on vast scales tractable to thinking. Geologic inquiry generates a plethora of maps and diagrams. The color-coding emblematic of geologic maps in effect contours the intersection of the landscape with time. Stratigraphic cross-sections are a ubiquitous tool. Correlation diagrams signify synchronous epochs in widely separated places. Series of block diagrams—affectionately referred to as “cartoons”—typify causal explanations and are used to compare models of how a landscape has unfolded through time. The metamorphic rocks of the Greater Himalayan slab present at least two associated anomalies: a normal fault above (given the collision of the Indian and Asian plates, thrust faults are expected) and a reversal of metamorphic grade upsection (higher grade—supposedly created at more extreme temperatures and pressures—above lower grade ones). A “metamorphic extrusion model,” quantitatively confirmed by geophysics and geochemistry, seems to resolve the anomaly. Block diagrams capture stages of the collision, faulting, and metamorphosing process. In the diagrams, rocks destined to become the peak of Mt. Everest begin as seafloor sediments, become pressure-cooked subterranean fare, and later enjoy uplift and exhumation (Searle, 2013).

8. Temporal Referee. Time is the referee! Ordering events in time is crucial to warranting geologic arguments. The chronology of events must cohere, synchronous in time across wide spaces and properly sequenced. A failed chronology or a lack of synchrony casts doubt upon claims and leads to demands for new inquiries. Based upon his conversations with the geologist Eldridge Moores about finding rocks born in ocean floor plates (“ophiolite sequences”) perched among continental mountain ranges, John McPhee summarized, “Sedimentary sequences, blue-schist belts, batholithic belts, thrust belts, and mélanges will orchestrally tell what happened. If they are not synchronous, it didn't happen” (McPhee, 1993, pp. 216-217). From studies at the scale of mineralization and fault propagation to hypotheses about plate subduction and mountain building, good geological inquiries interlock in mutually supporting and non-contradictory ways with time ever the referee (Author, 1998).

In summary, scientific thinking adapts to problem solving in diverse and productive ways. The events and objects of interest to geoscientists—historical phenomena that reside in deep time, complex systems, and multiple scales—present distinctive challenges to thought and inquiry. In order to interpret the earth both the methods of inquiry and the conceptions of phenomena must match the nature of these challenges.

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