Mission Areas L2 Landing Page Tabs
Tsunami: wave of change
No abstract available.Gesit, Eric L.; Titov, Vasily V.; Synolakis, Costas E.
Revisiting Frazier's subdeltas: enhancing datasets with dimensionality, better to understand geologic systems
Scientific knowledge from the past century is commonly represented by two-dimensional figures and graphs, as presented in manuscripts and maps. Using today's computer technology, this information can be extracted and projected into three- and four-dimensional perspectives. Computer models can be applied to datasets to provide additional insight...Flocks, James
Integration of coral reef ecosystem process studies and remote sensing: Chapter 5
Worldwide, local-scale anthropogenic stress combined with global climate change is driving shifts in the state of reef benthic communities from coral-rich to micro- or macroalgal-dominated (Knowlton, 1992; Done, 1999). Such phase shifts in reef benthic communities may be either abrupt or gradual, and case studies from diverse ocean basins...Brook, John; Yates, Kimberly; Halley, Robert
Constraining rates and trends of historical wetland loss, Mississippi River Delta Plain, south-central Louisiana
The timing, magnitude, and rate of wetland loss were described for five wetland-loss hotspots in the Terrebonne Basin of the Mississippi River delta plain. Land and water areas were mapped for 34 dates between 1956 and 2004 from historical National Wetlands Inventory (NWI) datasets, aerial photographs, and Landsat Thematic Mapper (TM) satellite...Bernier, Julie C.; Morton, Robert A.; Barras, John A.
Possible deep-water gas hydrate accumulations in the Bering Sea
Seismic reflection images from the deep-water Aleutian and Bowers Basins of the Bering Sea contain many hundreds of acoustic Velocity-AMPlitude (VAMP) anomalies, each of which may represent a large accumulation of natural gas hydrate. Against a backdrop of essentially horizontal sedimentary reflections, the VAMP anomalies stand out as both...Barth, Ginger A.; Scholl, David W.; Childs, Jonathan R.
A plastic flow model for the Acquara - Vadoncello landslide in Senerchia, Southern Italy
A previously developed model for stress and velocity fields in two-dimensional Coulomb plastic materials under self-weight and pore pressure predicts that long, shallow landslides develop slip surfaces that manifest themselves as normal faults and normal fault scarps at the surface in areas of extending flow and as thrust faults and thrust fault...Savage, W.; Wasowski, J.
Abrupt transitions during sustained explosive eruptions: Examples from the 1912 eruption of Novarupta, Alaska
Plinian/ignimbrite activity stopped briefly and abruptly 16 and 45 h after commencement of the 1912 Novarupta eruption defining three episodes of explosive volcanism before finally giving way after 60 h to effusion of lava domes. We focus here on the processes leading to the termination of the second and third of these three episodes. Early...Adams, N.K.; Houghton, Bruce F.; Hildreth, W.
Acoustic stratigraphy of Bear Lake, Utah-Idaho: late Quaternary sedimentation patterns in a simple half-graben
A 277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake's paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on...Colman, Steven M.
Age model for a continuous, ca 250-ka Quaternary lacustrine record from Bear Lake, Utah-Idaho
The Quaternary sediments sampled by continuous 120-m-long drill cores from Bear Lake (Utah-Idaho) comprise one of the longest lacustrine sequences recovered from an extant lake. The cores serve as a good case study for the construction of an age model for sequences that extend beyond the range of radiocarbon dating. From a variety of potential age...Colman, Steven M.; Kaufman, D.S.; Bright, Jordon; Heil, C.; King, J.W.; Dean, W.E.; Rosenbaum, J.G.; Forester, R.M.; Bischoff, J.L.; Perkins, Marie; McGeehin, J.P.
Airborne lidar sensing of massive stony coral colonies on patch reefs in the northern Florida reef tract
In this study we examined the ability of the NASA Experimental Advanced Airborne Research Lidar (EAARL) to discriminate cluster zones of massive stony coral colonies on northern Florida reef tract (NFRT) patch reefs based on their topographic complexity (rugosity). Spatially dense EAARL laser submarine topographic soundings acquired in August 2002...Brock, J.C.; Wright, C.W.; Kuffner, I.B.; Hernandez, R.; Thompson, P.
Airborne microorganisms in the African desert dust corridor over the mid-Atlantic ridge, Ocean Drilling Program, Leg 209
The objective of this study was to enhance our understanding of the fate and trans-Atlantic transport of dustborne microorganisms from Northern Africa to the Caribbean and Americas, and more specifically to determine if culturable populations could be detected at a mid-ocean site, closer to the source of dust relative to land-based Caribbean sites...Griffin, Dale W.; Westphal, Douglas L.; Gray, Michael A.
Airport geomagnetic surveys in the United States
The Federal Aviation Administration (FAA) and the United States military have requirements for design, location, and construction of compass calibration pads (compass roses), these having been developed through collaboration with US Geological Survey (USGS) personnel. These requirements are detailed in the FAA Advisory Circular AC 150/5300-13,...Berarducci, A.
On left, an example of a lidar image created from the “point cloud” that shows objects’ reflectivity near the Santa Cruz Beach Boardwalk and the mouth of the San Lorenzo River. On right, a digital still image overlaid onto the lidar “point cloud” data gives it a realistic 3D look.
This image is from a research camera positioned on the south rim of Mokuʻāweoweo, Mauna Loa's summit caldera, in Hawaiʻi Volcanoes National Park. The camera looks north-northwest, focusing on the southern part of the caldera. The 1940 cone is just right of center; the 1949 cone is on the caldera rim at left. The high point of Mauna Loa's summit is in the background....
Snapshot from a video camera at Isla Verde in San Juan, Puerto Rico, looking eastward. Every half hour during daylight hours, the camera shoots video for 10 minutes. This snapshot is the first frame in the 10-minute sequence.
Kīlauea Volcano's summit vent "then and now." In April 2008 (top image), a month after it opened, the vent within Halema‘uma‘u Crater was about 115 feet in diameter. As of March 2013 (bottom image), it is more than 500 feet across.
Image from video camera overlooking the coast along a beach on Whidbey Island, WA. Every half hour during daylight hours, the camera shoots video for 10 minutes. This snapshot is the first frame in the 10-minute sequence.