Publications

No abstract available.

In contrast to the rarity of such observations a decade ago, seismic reflecting and refracting horizons are now being observed to Moho depths under continental shelves in a number of places. These observations provide knowledge of the entire crustal thickness from the shoreline to the oceanic crust on passive margins and supplement Consortium for Continental Reflection Profiling (COCORP)...

High-resolution, single-channel and multichannel seismic-reflection profiles in the New York Bight provide 7 crossings of a 50-km-long fault that trends north-northeast for 30 km from its southern end, then bends northeast, and may continue northward beneath Long Island. Displacement, which is consistently down to the west, decreases upsection and suggests a growth fault. Dip of the...

The thick sequence of Miocene lava flows exposed on Steens Mountain in southeastern Oregon is well known for containing a detailed record of a reversed‐to‐normal geomagnetic polarity transition. Paleomagnetic samples were obtained from the sequence for a combined study of the directional and intensity variations recorded; the paleointensity study is reported in a companion paper. This...

French and United Kingdom workers have published reports describing a sudden change in the secular acceleration, called an impulse or a jerk, which took place around 1970. They claim that this change took place in a period of a year or two and that the sources of the alleged jerk are internal. An earlier paper by this author questioned their method of analysis pointing out that their...

No abstract available.

No abstract available.

No abstract available.

A widespread rhodolith facies occurs within middle Eocene limestones of Eua, Tonga (Fig. 1). These limestones, first described by Hoffmeister (1932), represent a portion of a broad, early Tertiary platform that developed in the Tonga area prior to disruption and uplift by later Tertiary plate movements (Kroenke and Tongilava 1975). Algal rhodoliths form beds several meters thick within...

GEOPROBE (Geological Processes Bottom Environmental) tripods were used to measure bottom currents, pressure, and light transmission and scattering and to obtain time-series photographs of the sea floor at depths of 23 m and 67 m on San Pedro shelf between 18 April and 6 June 1978. Winds were light ( 5 m/s) with a mean direction from the southwest throughout the measurement period. Hourly...

A major fault cutting through most of the crust can be identified and mapped on the Long Island platform using multichannel seismic reflection profiles and magnetic data. The fault, here called the Block Island fault (BIF), strikes north-northeast, dips westward at low angle, and does not resemble the thin-skinned thrust faulting observed in the foreland of the Appalachians. The BIF is...

Seismic profiles and bathymetric contours reveal a drowned barrier spit on Jeffreys Ledge off Cape Ann, Massachusetts. Seaward-dipping internal reflectors indicate that a regressive barrier formed during the early Holocene low sea-level stillstand. Preservation of the barrier spit may have been favored by its large size (as much as 20 m thick), by an ample sediment supply from...