Physical Sciences and Mathematics Commons^™

Seismic And Acoustic Signals Detected At Loihi Seamount By The Hawaii Undersea Geo-Observatory, Jacqueline Caplan-Auerbach, F. Duennebier

Geology Faculty Publications

The Hawai'i Undersea Geo-Observatory (HUGO) is an ocean bottom observatory located on the summit of Lo'ihi seamount, Hawai'i. An electro-optical cable connects the HUGO junction box to a shore station on the Big Island of Hawaii, thereby enabling the first real-time monitoring of a submarine volcano. HUGO was active for 3 months in 1998, collecting nearly continuous, real-time data on a high-rate hydrophone. Signals detected during that time include local as well as teleseismic earthquakes, T phases from Pacific-wide earthquakes, landslides on the submarine flank of Kilauea, and eruption sounds from the current Kilauea eruption. The data do not indicate …

Effects Of Sampling Standardization On Estimates Of Phanerozoic Marine Diversification, J. Alroy, C. R. Marshall, R. K. Bambach, K. Bezusko, M. Foote, F. T. Fürsich, Thor A. Hansen, S. M. Holland, L. C. Ivany, D. Jablonski, D. K. Jacobs, D. C. Jones, M. A. Kosnik, S. Lidgard, S. Low, A. I. Miller, P. M. Novack-Gottshall, T. D. Olszewski, M. E. Patzkowsky, D. M. Raup, K. Roy, J. J. Sepkoski Jr., M. G. Sommers, P. J. Wagner, A. Webber

Thor A. Hansen

Global diversity curves reflect more than just the number of taxa that have existed through time: they also mirror variation in the nature of the fossil record and the way the record is reported. These sampling effects are best quantified by assembling and analyzing large numbers of locality-specific biotic inventories. Here, we introduce a new database of this kind for the Phanerozoic fossil record of marine invertebrates. We apply four substantially distinct analytical methods that estimate taxonomic diversity by quantifying and correcting for variation through time in the number and nature of inventories. Variation introduced by the use of two …

Hydroacoustic Detection Of Submarine Landslides On Kilauea Volcano, Jacqueline Caplan-Auerbach, Christopher G. Fox, Frederick K. Duennebier

Geology Faculty Publications

Landslides produced at the site where lava flows into the ocean at Kilauea volcano have been detected hydroacoustically. Up to 10 landslides per day were detected by a hydrophone on the Hawaii Undersea Geo-Observatory (HUGO), located 50 km south of the entry site. The largest of these landslides, partly subaerial events known as bench collapses, were detected by a network of hydrophones in the eastern Pacific, 5000–7000 km away from the source. The landslides display a characteristic spectral signature easily recognizable among other signals such as earthquake T-phases and anthropogenic noises. The fact that signals are detected at great distances …

A Pebble Count Comparison And Rock Magnetism Provenance Study Of Sumas Outwash, Jeff Laub

WWU Graduate School Collection

The Sumas Stade, the last of the Fraser Glaciation advances, occurred between 12,000 and 10,000 ¹⁴C years B.P. This study combines previous mapping (Easterbrook, 1976; Haugerud, written communication, 1999) with three new tests to establish a chronology for events of the Sumas Stade. Comparison of compositions of pebbles from Sumas outwash using multivariate statistics such as hierarchical clustering and k-means clustering revealed three major groups of late Sumas outwash and one earlier deposit. Magnetic susceptibility and Curie temperature analysis determined a general British Columbia provenance for the Sumas outwash. Flow direction measurements substantiated this determination. Taken together, these tests …

Petrology And Geochemistry Of Mafic Lavas Near Glacier Peak, North Cascades, Washington, Dylan D. (Dylan Douglas) Taylor

WWU Graduate School Collection

Major element, trace element, and mineral compositions have been determined for four Quaternary mafic monogenetic cinder cones and flows south of Glacier Peak, a dacitic stratovolcano in the northern Cascade arc. The flows are the Whitechuck basalt, and the basaltic andesites of Indian Pass, Lightning Creek, and Dishpan Gap. Whitechuck has high concentrations of AI₂O₃ (≥ 18 wt.%) and low concentrations of K₂O (≤ 0.45 wt.%) and shares similar trace element characteristics with high alumina olivine tholeiites reported in the central and southern Cascades. The three basaltic andesites are calc-alkaline. Indian Pass and Lighting Creek …

Geology Of The Cooper Mountain Pluton, North Cascade Mountains, Washington Based On Magnetic Fabrics, Magnetic Remanence And Petrography, Tammy C. Fawcett

WWU Graduate School Collection

A study of the 48 Ma Cooper Mountain pluton (CMP) in the North Cascade Mountains of Washington using anisotropy of magnetic susceptibility (AMS) defined the orientation of magnetic fabrics. Fabrics in limited areas at the margins of the CMP tend to be parallel to the pluton margin and are therefore interpreted to be emplacement-related. The fabrics in the interior of the body, throughout the bulk of the pluton, are discordant with respect to the NW pluton margin. The fabric is manifest by NW-striking, moderately to steeply dipping foliation and NW-SE trending, moderately to shallowly plunging lineation, approximately parallel to regional …

Changes In Mirror Lake, Northwestern Washington, As A Result Of The Diversion Of Water From The Nooksack River, Karel Tracy

WWU Graduate School Collection

Mirror Lake, a small lake in northwest Washington, has been used as a settling pond for water diverted from the Middle Fork of the Nooksack River since 1962. In this thesis, I combine bathymetric data and sediment sampling to document the changes in sedimentation that have resulted from this diversion, and compare these results to a previous study conducted in 1991.

To document the change in the bathymetry of Mirror Lake since 1991, I surveyed the lake in the summer of 2000 using a theodolite and sonar depth gauge. I compared a contour map generated from this survey to the …

Late Pleistocene Littoral Deposits In The Deming Sand At Bellingham Bay, Washington, And Their Implications For Relative Sea Level Changes, Stacy J. (Stacy Joanna) Weber

WWU Graduate School Collection

Recent mass wasting of sea cliffs along Bellingham Bay in Northwest Washington has exposed late Pleistocene littoral deposits in the Deming sand, which is underlain by Kulshan glaciomarine drift (gmd) and overlain by Bellingham glaciomarine drift (Easterbrook 1963). Marine shells in the Kulshan gmd were dated at 12,210 ± 80 ¹⁴C-yrs B. P. and marine shells in the Deming sand were dated at 11,760 ± 85 and 11,685 ± 85 ¹⁴C-yrs B. P. Marine shells in the Bellingham gmd were dated at 12,150 + 210 ¹⁴C-yrs B. P.

Fossiliferous Kulshan glaciomarine drift is overlain by 11.5 m …

The Palaeomagnetism Of Lesbos, Ne Aegean, And The Eastern Mediterranean Inclination Anomaly, Myrl E. Beck Jr., Russ R. Burmester, Despina P. Kondopoulou, Artemios Atzemoglou

Geology Faculty Publications

Palaeomagnetic results for 44 sites in 16-22 Ma volcanic rocks from Lesbos, NE Aegean, yield a mean pole at 81.8ºN, 178.1º E, K = 9.0, A₉₅ = 7.6º. The mean direction for these sites (D =4.3º, I = 48.5º, k = 10.8, α ₉₅ = 6.9º) is 5.9º +/- 6.1º shallower than the reference direction for Miocene Lesbos calculated from Besse & Courtillot (1991). Combining these new data with previous work yields a mean inclination that is 5.6º +/- 4.7º too shallow. Experimental problems, magnetic anisotropy, the magnetic terrain effect, geomagnetic anomalies, and problems with the reference path …

Seismicity And Velocity Structure Of Loihi Seamount From The 1996 Earthquake Swarm, Jacqueline Caplan-Auerbach, F. K. Duennebier

Geology Faculty Publications

The largest earthquake swarm yet recorded on Loihi submarine volcano took place in July and August of 1996. The swarm consisted of two phases of seismic activity and was associated with the formation of a pit crater and additional faulting of Loihi’s summit platform. The first phase of activity was comprised of predominantly high-frequency events scattered over the southern flanks of the volcano. Following a day of seismic quiescence, the second phase of activity began, consisting of lower-frequency earthquakes with strong T-phases. The phase 2 events took place beneath Loihi’s summit, presumably marking the formation of the pit crater, Pele’s …