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H. R. Schmoll

Publications and source records attributed to H. R. Schmoll.

32 records · Page 2Linked to original sources
USGS1986

Description and interpretation of geologic materials from shotholes drilled for the Trans-Alaska Crustal Transect project, Copper River basin, Alaska, May 1985

This map shows the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity, Florida, for May 1986. The Upper Floridan aquifer is the principal source of potable water in the area. Water level measurements were made on approximately 1,000 wells and on several springs. The potentiometric surface is shown mostly by 5-foot contour intervals. In the Fernandina Beach area of Nassau County, a 30-ft. interval is used to show a deep cone of depression. The potentiometric surface ranged from 125 feet above sea level in Polk County to 75 feet below sea level in Nassau County. Water levels in most key wells ranged from 1 to 9 feet below the May average in response to the lack of recharge from rainfall and an attendant increase in pumpage. Many levels in the district were equal to or lower than the below average levels of May 1985. Declines of about a foot from May 1985 levels were common in the eastern half of the district. However, the largest declines from May 1985 levels, as much as 7 to 9 feet, were mostly in well fields along the coastline. Levels in many wells approached, and in a few wells exceeded, record lows. (USGS)

Open-File Report↗
USGS1984

Bedding types in Holocene tidal channel sequences, Knik Arm, Upper Cook Inlet, Alaska

Uplifted convoluted and horizontal to subhorizontal beds of varying thickness in intertidal silt as old as 3,280 + or - 90 yr B.P. are exposed in the banks of tidal channels of unknown depth in the intertidal zone in Knik Arm of Upper Cook Inlet. Internal discordances may occur both within convoluted beds and between convoluted and horizontal to subhorizontal beds. At the base of many convoluted beds, there is a rapid gradation upward into laminae which are severely deformed; that is, in some places, the contortions appear to have originated along a single bedding plane. Where the convoluted sequences are truncated by nearly horizontal sequences, the distortion must have resulted from syndepositional or postdepositional events prior to their burial by the overlying beds. Various forms of gravitational and tidal processes caused the deformation of the Knik Arm deposits; events triggering the movement of the sediment include any or all of the following: (1) seismic activity, (2) sediment or ice loading, (3) wave-induced liquefaction, (4) pore-pressure changes brought on by changing levels of tidewater, (5) undercutting of sediments by channel migration, and (6) freezing and thawing.

Journal of Sedimentary Petrology↗