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F.T. Manheim

Publications and source records attributed to F.T. Manheim.

49 records · Page 3Linked to original sources
USGS1971

Interstitial water studies on small core samples, Deep Sea Drilling Project, Leg 6

Sediments from Leg 6 sites, west of the Hawaiian Islands, consisted primarily of various combinations of deep-sea biogenic oozes, volcanic ash, and its breakdown products. Pore fluids from most of the sites were similar in composition to present day ocean water, and in some sties almost identical. However, interstitial fluids from Site 53 (Philippine Sea) showed changes in ionic composition which were beyond those previously considered attributable to diagenetic influence. These samples show the beginnings of metamorphism by dramatic increases in calcium concentrations and corresponding decreases in alkali concentrations. Analytical methods were similar to those outlined in previous Leg Reports. However, obvious contamination of aliquots for sodium determination in the laboratory made it necessary to determine all sodium values by difference between anion and cation balances. These values are, if anything, more accurate than direct determinations which have been discussed in earlier legs. However, the authors will continue to analyze sodium directly, and in the future they may be able to improve the precision of the determinations to the point where small losses and gains of sodium in the pore fluids may be established accurately. Agreement between colorimetric and spectrometric determinations of silicon has improved, but there are still occasional marked differences for which the writers have no explanation. T. Takahashi has allowed the authors to compare total Carbon Dioxide (CO 2 ) measurements from his laboratory with their alkalinity determinations: both sets of data were obtained from fluids from the same squeezings of sediments and should give similar values at the indicated pH levels. Some disturbingly large discrepancies in the two sets of data are evident. The authors do not think that their back-titration alkalinity technique alone is responsible for the differences. However, they have not evaluated the possible influence of the heat-sealed polyethylene pipes on the alkalinity values; this should be considered a potential source of error. The pH data from water samples processed and measured on shipboard are reported here. In view of the major changes in pressure and temperature (laboratory temperatures were reported to be 26 to 28°C) and the sediments to new gaseous regimes prior to pH measurement, these values should be interpreted mainly as applying to the squeezed effluents, not to in situ values.

Initial reports of the Deep Sea Drilling Project↗
USGS1971

Interstitial water studies on small core samples, Deep Sea Drilling Project, Leg 8

Leg 8 sites are dominated by siliceous-calcareous biogenic oozes having depositional rates of 0.1 to 1.5 cm/1000 years. Conservative constituents of pore fluids showed, as have cores from other pelagic areas of the Pacific, insignificant or marginally significant changes with depth and location. However, in Sites 70 and 71, calcium, magnesium and strontium showed major shifts in concentration with depth. These changes appear to be related to recrystallization phenomena in skeletal debris of nannoplankton and to the relative accumulation rate of the sediments. The chemical anomalies increase relatively smoothly with depth, demonstrating the effectiveness of vertical diffusional communication, and apparent lack of bulk fluid movement, as noted in Leg 7 and other sites.

Initial reports of the Deep Sea Drilling Project↗
USGS1970

The diffusion of ions in unconsolidated sediments

Diffusion in unconsolidated sediments generally proceeds at rates ranging from half to one twentieth of those applying to diffusion of ions and molecules in free solution. Diffusion rates are predictable with respect to porosity and path tortuosity in host sediments, and can be conveniently measured by determinations of electrical resistivity on bulk sediment samples. Net ion flux is further influenced by reactions of diffusing species with enclosing sediments, but such influences should not be confused with or lumped with diffusion processes.

Earth and Planetary Science Letters↗
USGS1970

Suspended matter in surface waters of the Atlantic continental margin from Cape Cod to the Florida Keys

Appreciable amounts of suspended matter (> 1.0 milligram per liter) in surface waters are restricted to within a few kilometers of the Atlantic coast. Particles that escape estuaries or are discharged by rivers into the shelf region tend to travel longshoreward rather than seaward. Suspended matter farther offshore, chiefly amorphous organic particles, totals 0.1 milligram per liter or less. Soot, fly ash, processed cellulose, and other pollutants are widespread.

Atlantic Coast, Cape Cod to the Florida Keys↗
USGS1970

Brines and interstitial brackish water in drill cores from the deep Gulf of Mexico

Marked increases in interstitial salinity occur in two drill holes located in the Gulf of Mexico at a water depth of more than 3500 meters. The increases probably arose through diffusion of salt from buried evaporites. In one hole, however, brackish water was encountered on penetrating the oil-permeated cap rock of a salt dome. The phenomenon is attributed to production of fresh water during oxidation of petroleum hydrocarbons and decomposition of gypsum to form native sulfur.

Science↗
USGS1970

Interstitial water studies on small core samples, Deep Sea Drilling Project, Leg 3

Eleven samples of fluids which had been squeezed on board ship, and four, packaged sediment samples were received in our laboratories. As in Leg 2, the volumes of fluid available were scanty and did not permit multiple determinations of constituents in many of the samples; in Hole 21 the fluid available sufficed only for refractometer readings (a few tenths of a milliliter). Therefore, analytical scatter is again responsible for partially obscuring variations (and constancy) in the conservative constituents such as sodium. However, on the whole the results confirm the features which appeared in Legs 1 and 2. Central oceanic sediments display a remarkable constancy in total salinity, chlorinity and sodium concentration to the greatest depths and ages yet penetrated in the project drillings. Variations attributable to postburial reactions do occur in the remaining major ions, but they usually show little systematic trend with depth--with the exception of potassium, which will be discussed later. Methods remain similar to those employed for Leg 2; the detailed techniques are now being prepared for submission, but a brief description may be obtained from the previous Leg reports (Manheim and Sayles, 1969; Chan and Manheim, 1970). Results from four unsqueezed samples are not complete and, therefore, do not appear here.

Initial reports of the Deep Sea Drilling Project↗
USGS1970

Interstitial water studies on small core samples, Deep Sea Drilling Project, Leg 5

Leg 5 samples fall into two categories with respect to interstitial water composition: 1) rapidly deposited terrigenous or appreciably terrigenous deposits, such as in Hole 35 (western Escanaba trough, off Cape Mendocino, California); and, 2) slowly deposited pelagic clays and biogenic muds and oozes. Interstitial waters in the former show modest to slight variations in chloride and sodium, but drastic changes in non-conservative ions such as magnesium and sulfate. The pelagic deposits show only relatively minor changes in both conservative and non-conservative pore fluid constituents. As was pointed out in earlier Leg Reports, it is believed that much of the variation in chloride in pore fluids within individual holes is attributable to the manipulation of samples on board ship and in the laboratory. On the other hand, the scatter in sodium is due in part to analytical error (on the order of 2 to 3 per cent, in terms of a standard deviation), and it probably accounts for most of the discrepancies in total anion and cation balance. All constituents reported here, with the exception of bulk water content, were analyzed on water samples which were sealed in plastic tubes aboard ship and were subsequently opened and divided into weighed aliquots in the laboratory. Analytical methods follow the atomic absorption, wet chemical and emission spectrochemical techniques briefly summarized in previous reports, e.g. Manheim et al., 1969, and Chan and Manheim, 1970. The authors acknowledge assistance from W. Sunda, D. Kerr, C. Lawson and H. Richards, and thank D. Spencer, P. Brewer and E. Degens for allowing the use of equipment and laboratory facilities.

Initial reports of the Deep Sea Drilling Project↗
USGS1969

Geochemistry of pore waters from Shell Oil Company drill holes on the continental slope of the northern Gulf of Mexico

Pore waters were analyzed from 6 holes drilled from M.V. “Eureka” as a part of the Shell Oil Co. deeper offshore study. The holes were drilled in water depths of 600–3,000 ft. (approximately 180–550 m) and penetrated up to 1,000 ft. (300 m) of Pliocene-Recent clayey sediments. Salt and anhydrite caprock was encountered in one diapiric structure on the continental slope. Samples from holes drilled near diapiric structures showed systematic increases of pore-water salinity with depth, suggestive of salt diffusion from underlying salt plugs. Anomalous concentrations of K and Br indicate that at least one plug contains late-stage evaporite minerals. Salinities approaching halite saturation were observed. Samples from holes away from diapiric structures showed little change in pore-water chemistry, except for loss of SO 4 and other variations attributable to early-stage diagenetic reactions with enclosing sediments. Thus, increased salt concentrations in even shallow sediments from this part of the Gulf appear to provide an indicator of salt masses at depth.

Chemical Geology↗
USGS1968

Disposable syringe techniques for obtaining small quantities of pore water from unconsolidated sediments

Disposable plastic syringes, fitted with screen discs and circles of filter paper, can be used to extract small amounts of pore water from unconsolidated sediments. A wooden screw frame or large C clamp supplies pressure for field use. Supplementary techniques enable small volumes of fluid to be recovered and handled easily. The Goldberg compensating refractometer provides a useful companion tool for field studies. It can determine, in less than a minute, total dissolved solids in brackish to salt waters to an accuracy of 0.5 parts per thousand on a drop of fluid.

Journal of Sedimentary Research↗
USGS1966

Hot brines and recent iron deposits in deeps of the Red Sea

Sedimentary iron and heavy-metal deposits of undetermined size have been found in the middle of the Red Sea some 2000 meters below the surface of the sea (Fig. 1). This discovery has been made from the Research Vessel Atlantis II , which is still at sea engaged in a series of oceanographic investigations which ultimately will end in November 1965, after the ship has circumnavigated the globe. The discovery is significant because the environment and the processes controlling deposition of heavy metals are observable and appear to be still active.

Geochimica et Cosmochimica Acta↗
USGS1966

Soviet books and publications on geological and chemical oceanography, hydrology, and other subjects acquired during the second international oceanographic congress, Moscow, June 1966: titles and some translated contents and notes

The listed publications represent a selection, by no means complete, of recent Soviet work in geological and chemical oceanography. Some works on hydrogeology and hydrochemistry of the continents, as well as a few publications on other subjects, such as geology, geophysics, and biology, also are included.

Report↗
USGS1965

Hot brines and recent iron deposits in deeps of the Red Sea

Sedimentary iron and heavy-metal deposits of undetermined size have been found in the middle of the Red Sea some 2000 meters below the surface of the sea. This discovery has been made from the Research Vessel Atlantis II , which is still at sea engaged in a series of oceanographic investigations which ultimately will end in November 1965, after the ship has circumnavigated the globe. The discovery is significant because the environment and the processes controlling deposition of heavy metals are observable and appear to be still active. The environment of the deposits can be breiefly described as an isolated sub-marine pool of brine having a pH as low as 5.3, a temperature of 56° c. and a salt content of about 310 grams per liter (at 20° c). Shipboard oxygen determinations and the indicated presence of H 2 S, divalent iron and divalent manganese in the water suggest that the environment is anaerobic. This hot, dense brine is trapped in a local depression of the Red Sea median valley. (Atlantis II Deep). The iron deposits, consisting largely of hydrous iron oxides, are found in the same depression. Brines from the Discovery Deep (21° 17 1 N, 38° 02'E) (1), a few miles southwest of the Atlantis II Deep (21°21 1 N, 38 ° 04'E), have a pH of 6.2 and a temp­erature of 44.7° c, and are also associated with iron-bearing sedirnents. The Discovery and Atlantis II brine pools both extend about 150 meters above the bottom. A few miles south of the: Discovery Deep another depression of greater depth has been reported (2) containing essentially normal Red Sea water. Deeps several hundred miles to the north (Sta. 540) and south (Sta. 545) were investigated and contained no brine. One of these (Sta. 545) is known to contain normal sediments.

Open-File Report↗