Publications
Filter Total Items: 3126
Magmatic inclusions in silicic and intermediate volcanic rocks Magmatic inclusions in silicic and intermediate volcanic rocks
Fine‐grained ellipsoidal inclusions from a few millimeters to over l m in size are present in many intermediate to silicic lava flows and domes. Only recently has it become widely accepted that such inclusions are chilled blobs of magma. Their magmatic origin is manifested by vesicularity and high groundmass porosity, by ellipsoidal shapes, by mingling at contacts with the host, and by...
Authors
Charles R. Bacon
A history of paleoflood hydrology in the United States A history of paleoflood hydrology in the United States
The origins of paleoflood hydrology in the United States can be traced back to the beginning of the 19th century, when windgaps and watergaps in the Applachians were believed to have been eroded by extraordinary floods as large lakes that were ponded behind the ridges rapidly drained. Sediment evidence for extraordinary floods was evoked several decades later when glacial sediments in...
Authors
John E. Costa
Book review of Slope Instability, D. Brunsden and D.B. Prior, eds., Wiley, New York, 620 p. Book review of Slope Instability, D. Brunsden and D.B. Prior, eds., Wiley, New York, 620 p.
No abstract available.
Authors
Richard M. Iverson
Signs of a northeastern earthquake? Signs of a northeastern earthquake?
No abstract available.
Authors
R.L. Kerr
Parkfield earthquake looks to be on schedule Parkfield earthquake looks to be on schedule
No abstract available.
Authors
R. A. Kerr
Lithic breccia and ignimbrite erupted during the collapse of Crater Lake Caldera, Oregon Lithic breccia and ignimbrite erupted during the collapse of Crater Lake Caldera, Oregon
The climactic eruption of Mount Mazama (6845 y.B.P.) vented a total of ∼50 km3 of compositionally zoned rhyodacitic to basaltic magma from: (a) a single vent as a Plinian pumice fall deposit and the overlying Wineglass Welded Tuff, and (b) ring vents as ignimbrite and coignimbrite lithic breccia accompanying the collapse of Crater Lake caldera. New field and grain-size data for the ring...
Authors
T. H. Druitt, C. R. Bacon
Implications of silicic vent patterns for the presence of large crustal magma chambers Implications of silicic vent patterns for the presence of large crustal magma chambers
On the basis of the distribution of silicic vents, many volcanic fields can be grouped with (1) igneous systems that may be small and whose vent locations are controlled by regional tectonics, (2) those that include sizable crustal magma bodies which erupt at sites determined by their anomalous local stress fields, or (3) relatively small volume systems that are transitional between...
Authors
Charles R. Bacon
A constitutive equation for mass-movement behavior A constitutive equation for mass-movement behavior
A phenomenological constitutive equation can serve as a basis for modeling and classifying mass-movement processes. The equation is derived using the principles of continuum mechanics and several simplifying assumptions about mass-movement behavior. These assumptions represent idealizations of field behavior, but they appear highly justifiable in light of the geomorphological insight...
Authors
Richard M. Iverson