Chronology of alluvial terrace sediment accumulation and incision in the Pativilca Valley, western Peruvian Andes

The greater Taos trough located in north-central New Mexico represents one of numerous late Paleozoic basins that formed during the Ancestral Rocky Mountains deformation event. The late Paleozoic stratigraphy and basin geometry of the eastern portion of the greater Taos trough, also called the Rainsville trough, is little known because the strata are all in the subsurface. Numerous wells drilled through the late Paleozoic strata provide a scope for investigating subsurface stratigraphy and basin-fill architecture of the Rainsville trough. Lithologic data obtained predominantly from petrophysical well logs combined with available biostratigraphic data from the greater Taos trough allows construction of a chronostratigraphic framework of the basin fill. Isopach- and structure-maps indicate that the sediment depocenter was just east of the El Oro-Rincon uplift and a westerly thickening wedge-shaped basin-fill geometry existed during the Pennsylvanian. These relationships imply that the thrust system on the east side of the Precambrian-cored El Oro-Rincon uplift was active during the Pennsylvanian and segmented the greater Taos trough into the eastern Rainsville trough and the western Taos trough. During the Permian, sediment depocenter(s) shifted more southerly and easterly and strata onlap Precambrian basement rocks of the Sierra Grande uplift to the east and Cimarron arch to the north of the Rainsville trough. Permian strata appear to demonstrate minimal influence by faults that were active during the Pennsylvanian and sediment accumulation occurred both in the basinal area as well as on previous positive-relief highlands. A general Permian decrease in eustatic sea level and cessation of local-fault-controlled subsidence indicates that regional subsidence must have affected the region in the early Permian.

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Faculty of 1000 evaluation for Intra- and interspecific tree growth across a long altitudinal gradient in the Peruvian Andes.

F1000 - Post-publication peer review of the biomedical literature ◽

10.3410/f.717960448.793463554 ◽

2012 ◽

Author(s):

Janneke Hille Ris Lambers

Keyword(s):

Tree Growth ◽

Altitudinal Gradient ◽

Peruvian Andes

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Faculty Opinions recommendation of Intra- and interspecific tree growth across a long altitudinal gradient in the Peruvian Andes.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717968570.793463554 ◽

2012 ◽

Author(s):

Janneke Hille Ris Lambers

Keyword(s):

Tree Growth ◽

Altitudinal Gradient ◽

Peruvian Andes

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Submerged Macrophyte Control Using Plastic Blankets

Water Science & Technology ◽

10.2166/wst.1994.0172 ◽

1994 ◽

Vol 29 (4) ◽

pp. 119-126

Author(s):

D. R. Carter ◽

S. Carter ◽

J. L. Allen

Keyword(s):

Plant Species ◽

Sediment Accumulation ◽

Submerged Macrophyte ◽

Light Reduction ◽

Control Options ◽

Macrophyte Growth ◽

Gravel Pits ◽

End Use ◽

Potential Area

Penrith Lakes Scheme is concerned with the rehabilitation of gravel pits to create a system of large recreational lakes. A potential submerged macrophyte problem has been identified in an existing man-made lake. The need to control the macrophytes is dependent on the proposed end use of the lakes and the potential area of invasion. A variety of control options were assessed. Plastic blankets were tested to determine their effectiveness in controlling macrophyte growth specifically in swimming and boat access areas. Comparisons of clear, black and black woven blankets were conducted. Experiments revealed that 90% of the plants under the black and black woven blankets died within six weeks. Under clear blankets plants were reduced by between 20%-90%. Analysis showed that significant interactions occurred between sites and treatments and times, from which it can be inferred that none are independent of each other. Success in the reduction of macrophytes appears dependent on such factors as plant species, sediment accumulation and light reduction.

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Integrative Assessment of Sediment Quality History in Pulp Mill Recipient Area in Finland

Water Science & Technology ◽

10.2166/wst.1999.0705 ◽

1999 ◽

Vol 40 (11-12) ◽

pp. 139-146 ◽

Cited By ~ 2

Author(s):

Mika A. Kähkönen ◽

Mikko Liukkonen ◽

Christoph Wittmann ◽

Kimmo P. Suominen ◽

Mirja S. Salkinoja-Salonen

Keyword(s):

Vibrio Fischeri ◽

Sediment Quality ◽

Sediment Accumulation ◽

Pulp Mill ◽

Complete Recovery ◽

Heavy Metal Accumulation ◽

Atp Content ◽

Bleached Kraft Pulp ◽

Elemental Chlorine ◽

Integrative Assessment

Sediments were dated and the quality assessed by polyphasic approach in an area of Lake Saimaa, which has received waste water from bleached kraft pulp production since 1954. The chosen nonrecipient forest Lake Pyylampi was situated in the same area. The activities of the enzymes butyrate-esterase and aminopeptidase were depressed at the depth of 2 to 8 cm in the recipient but not in the forst lake sediment. In the same layers the contents of EOX-C1 and toxicity to Vibrio fischeri were very high compared to those above or below. Toxicity to microbial community in the 2 to 8 cm layer was also indicated by a gap in the ATP content and a drop in diatom species richness from the 70 species to < 50 reflecting decreased water quality of the pelagic area. All these changes dated to the period of heavy organic halogen discharges, from 1960 to late 1980s, which led to sediment accumulation of solvent soluble halogen at a depth of 2 to 8 cm, to 6.4 g m−2 (cm)−1. In the most polluted sediment layers heavy metal accumulation was too little to be related to the toxicity of these layers. Almost complete recovery of both the sediment microbial ecosystems and of the pelagic diatoms occurred after elemental chlorine was completely substituted by chlorine dioxide and biological treatment adopted for wastewaters. Butyrate-esterase and aminopeptidase, but not phosphatase, activities correlated positively with the ATP content of the sediment. Butyrate-esterase may be used as a tool to estimate microbial biomass.

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