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Explore the world of dendrogeomorphology with examples like dating earthquakes on the San Andreas Fault, Parícutin eruption research, and Sunset Crater preparations. Learn how dendrogeomorphology detects changes in tree ring growth, wood density, and dates significant events. Witness how it unravels mysteries of Hebgen Lake, 1959, and investigates seismic, volcanic, and other ground events through tree analysis. Discover the fundamentals of dendrogeomorphology, including crossdating, control, and mapping. Dive into Dendrogeomorphology Quadruple Junction and Dendroseismology in Southern California, unveiling insights from tree data on past seismic events. Presenting Dendrovolcanism at Sunset Crater, this compelling field offers a unique lens into understanding Earth's processes and predicting future events.
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Dendrogeomorphology • Background lecture • Various examples • Web images • Old business: • Dating, discovering previously unknown earthquake on southern San Andreas • New business: • Current research on Parícutin eruption • Prep for Sunset Crater
How Dendrogeomorphology • Any unusual change in ring growth • Decreased/increased width growth • Decreased/increased ring wood density
How Dendrogeomorphology • Any unusual change in ring growth • Decreased/increased width growth • Decreased/increased ring wood density • Death/initiation date
How Dendrogeomorphology • Any unusual change in ring growth • Decreased/increased width growth • Decreased/increased ring wood density • Death/initiation date • Reaction wood/abrasion scar
How Dendrogeomorphology • Any unusual change in ring growth • Decreased/increased width growth • Decreased/increased ring wood density • Death/initiation date • Reaction wood/abrasion scar • Ring chemical changes • Nitrogen? • Strontium?
What Dendrogeomorphology • Earthquakes: 1989 Loma Prieta
What Dendrogeomorphology • Earthquakes • Volcanic eruptions
What Dendrogeomorphology • Earthquakes • Volcanic eruptions • Other ground • Mud/debris flow, rockfall • Soil creep
What Dendrogeomorphology • Earthquakes • Volcanic eruptions • Other ground • Mud/debris flow, rockfall • Soil creep • Water • Shoreline • Riverine
What Dendrogeomorphology • Aeolian • Great L. dunes • Earthquakes • Volcanic eruptions • Other ground • Mud/debris flow, rockfall • Soil creep • Water • Shoreline • Riverine
What Dendrogeomorphology • Aeolian • Great L. dunes • Earthquakes • Volcanic eruptions • Snow • Neo advances • Avalanches (Dexter) • Permafrost • Ice ramparts, jams • http://www.neatorama.com/2007/05/31/frozen-waves/ • Other ground • Mud/debris flow, rockfall • Soil creep • Water • Shoreline • Riverine
What Dendrogeomorphology • Aeolian • Great L. dunes • Earthquakes • Volcanic eruptions • Snow • Neo advances • Avalanches (Dexter) • Permafrost • Ice ramparts, jams • http://www.neatorama.com/2007/05/31/frozen-waves/ • Other ground • Mud/debris flow, rockfall • Soil creep • Water • Shoreline • Riverine
Why Dendrogeomorphology • Basic understanding of surficial processes • Dates, therefore frequency of events • Location, areal extent • Magnitude • Temporal-spatial coherence • E.g., volcanism related to seismicity? • Medicine Lake Highlands
Why Dendrogeomorphology • Basic understanding of surficial processes • Dates, therefore frequency of events • Location • Magnitude • Temporal-spatial coherence • E.g., volcanism related to seismicity? • Medicine Lake Highlands • Future prediction not a goal so much
Dendrogeomorphology Fundamentals • Uniformitarianism • Events affect trees similarly • Absolute conditions need not be similar • Limiting factors • Events change what limits tree growth • Site selection • Certainly not random • Carefully considered
Dendrogeomorphology Fundamentals • Crossdating • Annual precision a strength of dendro • Getting “close” could be misleading • Sensitivity • Enough to facilitate crossdating • Not too much, mimic geomorphic signal • Replication • How many trees with geomorphic signal?
Dendrogeomorphology Fundamentals • Control (expectation) • Growth prior to event • Growth of other trees after event • Departure from expectation • Also caused by climate, ecological events • Mapping often critical • Calibration to known event would be nice • Vanishing evidence
DendrogeomorphologyQuadruple Junction • Geomorphic process, frequent and recent • Must damage trees without destroying evidence • Must be old trees, with crossdating • Compelling hazard to humans
Dendroseismology:Southern California • Recent event (1857), previous event thought to be within 200 years • Living trees show 1857 event • Long-lived pines and firs • Millions of people living nearby, some right on the San Andreas
Pool Tree • Huge Jeffrey • No top • Sag pond pool
Lone Pine Canyon • Huge Jeffrey • No top • Right on fault
All Trees • Control chronology robust • 1812 & 1857 drought years? • Nine event trees • Pines, firs • Confirm 1857, show 1812 • Span 12 km of fault
San JuanCapistrano • 60 km south of Wrightwood • Big earthquake in 1812, Dec. 8.
Interpretation • Short segment ruptured, but longer than our trees • The word “irregular” made it in title • 1812 45 yrs • 1857 146 yrs • 2003
Another Interpretation • Seismic ruptures displace stress, rather than eliminate it (SciAm, Jan. 2003) • Stress displaced to the north? • 1812 southern California 45 yrs • 1857 central California 49 yrs • 1906 San Francisco • When will south start again?
Dendrovolcanism:Sunset Crater • Last event not very recent (AD 1064?) • Trees from archeo collections show that event • Crossdating legendary • Sinaguans lived nearby • Calibration from Parícutin 1940s?
Questions About Sunset • Nature of association of event trees with eruption? • Eruption perhaps a lengthy event? • Did ash truly improve environmental conditions for Sinagua? • “Blank Sand,” by Colton?
Parícutin, Mexico • Cinder cone, similar to Sunset • Well known modern event • 1940s-50s eruption • Lava, ash fall well-mapped • Forested area, then and now • Perhaps could serve as a calibration for Sunset
Parícutin • Big, young pines • Most start in 1960s • A few start in 1930s • Some old stumps • Dating not great, but passable • Measure widths and elements • S, P
Interpretation (so far) • Clear visible effects on this tree • P and Ca response might be indirect soil pH changes • Either way, a useful chemical variable • Will this show up in Sunset Crater archeo wood collection? • Could refine start date of eruption • Could better define length of eruption
Dendovolvanics Mount St. Helens • A virtual dendrogeomorph playground • Recent eruptions • Lots of old trees • Lots of people
1842 1843 1845