scholarly journals Distribution of Sites and Radiocarbon Dates in the Sierra Nevada: Implications for Paleoecological Prospecting

Radiocarbon ◽  
1997 ◽  
Vol 39 (2) ◽  
pp. 121-137 ◽  
Author(s):  
R. Scott Anderson ◽  
Susan J. Smith ◽  
Peter A. Koehler
Keyword(s):  
Lake Sediments ◽  
Sierra Nevada ◽  
Temporal Distribution ◽  
East Side ◽  
The West ◽  
West Side ◽  
Radiocarbon Dates ◽  
Time Periods

The number of paleoecological records for the Sierra Nevada of California has increased substantially since the compilation of Adam (1985). We examine here the geographical and temporal distribution of records within the range in order to identify areas for which “gaps” exist in our paleoecological knowledge. Seventy-two sites with paleoecological information are identified; these sites are dated with 234 radiocarbon dates. Sites occur primarily between ca. 36°N and 38°30'N latitudes, and from ca. 1000 m to over 3000 m elevation on both sides of the Sierran crest, although more sites have been analyzed on the west side of the crest than the east side. In general, packrat (Neotoma) midden series are located at the lowest elevations, meadow and marsh cores originate from mid-elevations, and lake sediments have been analyzed from the highest elevations. Significant gaps in our knowledge occur for much of the east side of the crest, for both sides of the range above modern treeline, and for time periods older than the latest Pleistocene.

scholarly journals 41AN28: An Ancestral Caddo Settlement on Mound Prairie Creek in the Neches River Basin in East Texas

2015 ◽  
Author(s):  
Timothy K. Perttula
Keyword(s):  
River Basin ◽  
East Texas ◽  
East Side ◽  
Alluvial Terrace ◽  
The West ◽  
West Side ◽  
Radiocarbon Dates ◽  
Post Oak ◽  
Neches River

Site 41AN28 is an extensive ancestral Caddo settlement on an alluvial terrace on the west side of Mound Prairie Creek in the Post Oak Savannah of East Texas. Mound Prairie Creek is an southward- and eastward-flowing tributary to the Neches River. The confluence of the two streams lies about 20 km to the east. Directly to the east of 41AN28 on the east side of Mound Prairie Creek lies the Pace McDonald site (41AN51). This site is an important Middle Caddo period (ca. A.D. 1200-1400) mound center with at least two earthen mounds and a settlement that covers more than 11 acres. Both investigated mounds at Pace McDonald were built to cover and bury special purpose structures where significant deposits of ash were accumulated, probably ash temples like those uncovered in the main mound at the nearby A. C. Saunders site (41AN19). Two calibrated radiocarbon dates from habitation areas at the Pace McDonald site range from A.D. 1200-1410.

The Cedar Mountain, Nevada, earthquake of December 20, 1932*

1934 ◽  
Vol 24 (4) ◽  
pp. 345-384 ◽  
Author(s):  
Vincent P. Gianella ◽  
Eugene Callaghan
Keyword(s):  
Sierra Nevada ◽  
Horizontal Displacement ◽  
Vertical Displacement ◽  
Relative Movement ◽  
East Side ◽  
Owens Valley ◽  
The West ◽  
Horizontal Movement ◽  
San Andreas

Summary The Cedar Mountain, Nevada, earthquake took place at about 10h 10m 04s p.m., December 20, 1932. It was preceded by a foreshock noted locally and followed by thousands of aftershocks, which were reported as still continuing in January 1934. No lives were lost and there was very little damage. The earthquake originated in southwest central Nevada, east of Mina. A belt of rifts or faults in echelon lies in the valley between Gabbs Valley Range and Pilot Mountains on the west and Cedar Mountain and Paradise Range on the east. The length of this belt is thirty-eight miles in a northwesterly direction, and the width ranges from four to nine miles. The rifts consist of zones of fissures which commonly reveal vertical displacement and in a number of places show horizontal displacement. The length of the rifts ranges from a few hundred feet to nearly four miles, and the width may be as much as 400 feet. The actual as well as indicated horizontal displacement is represented by a relative southward movement of the east side of each rift. The echelon pattern of the rifts within the rift area indicates that the relative movement of the adjoining mountain masses is the same. The direction of relative horizontal movement corresponds to that along the east front of the Sierra Nevada at Owens Valley and on the San Andreas rift.

scholarly journals Fabric and Origin of Lateral Moraines, Bethartoli Glacier, Garhwal Himalaya, India

1978 ◽  
Vol 20 (84) ◽  
pp. 547-553 ◽  
Author(s):  
Gerald D. Osborn
Keyword(s):  
Garhwal Himalaya ◽  
Lateral Moraine ◽  
East Side ◽  
The West ◽  
West Side ◽  
Lateral Ridge ◽  
Moraine Ridge

AbstractUnusually strong till fabrics in lateral moraines of Bethartoli Glacier provide information on the genesis and growth of the moraines. On the west side of the valley, down-stream of the present glacier snout, several lateral moraine crests are juxtaposed. Because the crests generally become higher towards the valley axis, they must represent re-advances of the glacier rather than recessional stages. On the east side of the valley only a single lateral ridge is found; presumably the ridge is composed of debris from several glacial advances. On the eroded proximal flank of this ridge a strong fabric is visible; the plane defined by a- and b-axes of stones is parallel to the distal flank of the moraine ridge, indicating that the moraine grew mainly by accretion of debris on to its distal flank. On the eroded proximal flank of the innermost west-side ridge the equivalent fabric is weaker, suggesting that distal flank accretion was less significant and proximal flank accretion more significant than on the east side.

Geodetic measurements in the Dixie Valley Area

1957 ◽  
Vol 47 (4) ◽  
pp. 321-325
Author(s):  
C. A. Whitten
Keyword(s):  
Valley Floor ◽  
Similar Amount ◽  
East Side ◽  
The West ◽  
West Side ◽  
Geodetic Measurements ◽  
Vertical Displacements ◽  
Dixie Valley ◽  
Valley Area

abstract Resurveys made after the 1954 earthquake in the Dixie Valley Area determined the horizontal and vertical displacements which occurred. Triangulation stations on the west side of the fault moved north approximately 4 feet, and points on the east side moved south by a similar amount. Releveling showed a drop and also a tilt of a valley floor.

An 1800-year record of the spatial and temporal distribution of fire from the west coast of Vancouver Island, Canada

2003 ◽  
Vol 33 (4) ◽  
pp. 573-586 ◽  
Author(s):  
Daniel G Gavin ◽  
Linda B Brubaker ◽  
Kenneth P Lertzman
Keyword(s):  
West Coast ◽  
Temporal Distribution ◽  
Source Area ◽  
Vancouver Island ◽  
Ice Age ◽  
Sediment Record ◽  
The West ◽  
Radiocarbon Dates ◽  
Soil Charcoal ◽  
In Fire

Charcoal records from lake sediments may show changes in fire frequency over thousands of years, but such records are ambiguous with regard to the actual locations of fires. Using a comparison of fire dates from an 1800-year lake sediment record from the west coast of Vancouver Island (British Columbia, Canada) and dates of last fire from 38 sites in the same watershed using tree-ring and soil-charcoal 14C dates, we estimated the source area that contributes to charcoal peaks and determined the degree to which fires were biased to certain locations. Twenty-three charcoal peaks, likely corresponding with individual fire events, were objectively identified from the sediment record. Comparison of fire dates from charcoal peaks in the sediment record with fire dates from points near the lake suggests that the charcoal source area is within 500 m of the lake edge. Fire occurrence within this charcoal source area increased sharply at AD 1100 from ca. 50 to ca. 300 years between charcoal peaks, coeval with the first "Little Ice Age" cooling. Soil-charcoal radiocarbon dates revealed that 37% of the charcoal source area had not burned over the last 1800 years and that the 23 fires identified in the sediment record were restricted to south-facing slopes near the lake. This spatial pattern may result only if fire is >25 times more likely to occur on susceptible sites (south-facing slopes) than on less susceptible sites. This strong bias in fire location ensured the millennial-scale persistence of large areas of late-successional forest through past climatic periods.

Sierra Motherlode, Domain 2

2007 ◽  
Author(s):  
Earl B. Alexander ◽  
Roger G. Coleman ◽  
Todd Keeler-Wolfe ◽  
Susan P. Harrison
Keyword(s):  
Sierra Nevada ◽  
Western Slope ◽  
Mountain Range ◽  
Serpentine Soils ◽  
East Side ◽  
The West ◽  
Eastern Side ◽  
The North ◽  
Great Valley ◽  
Block Faulting

The Sierra Motherlode domain is in a series of allochthonous terranes, sometimes called the “Foothill Belt,” along the western edge of the north-northwest–south-southeast trending Sierra Nevada, adjacent to the Great Valley of California. It is a discontinuous belt from the southern Sierra Nevada, in Tulare and Fresno counties, to Butte County in the northern Sierra Nevada , but a branch within the belt is practically continuous from El Dorado County about 140 km north to Plumas County at the north end of the range. Cenozoic block faulting has lifted the Sierra Nevada and tilted the mountain range toward the west; therefore the highest elevations are on the east side of the range. Uplift is more pronounced in the southern than in the northern Sierra Nevada. Altitudes range from <200 m adjacent to the Great Valley to more than 4000 m along the crest of the central to southern part of the mountain range. The highest altitudes in the Sierra Motherlode domain are 1939 m (6360 feet) on Red Mountain and 1935 m (6335 feet) on Red Hill in Plumas County, and even higher on some of the granitic plutons that are within the outer limits of the serpentine domain. These plutons were intruded into the allochthonous terranes after the terranes had been accreted onto the continent. Much of the western slope of the northern Sierra Nevada is an undulating to rolling plateau. This plateau is a remnant from the early Tertiary when its surface was deeply weathered to produce lateritic serpentine soils with silica deposited in the subsoils and in fractures in the bedrock (Rice and Cleveland 1955, Rice 1957). The ancient plateau was capped by volcanic flows that produced a practically continuous cover in the northern Sierra Nevada (Durrell 1966). Uplift along the eastern side of the northern part of the Sierra Nevada to initiate its current relief commenced 4 or 5 Ma ago (Wakabayashi and Sawyer 2001). Since the range began to rise a few million years ago, the larger streams flowing across it have cut deep canyons up to about 600 m below the plateau.

Characterization of soil P in coastal forest chronosequences of southern Vancouver Island: effects of climate and harvesting disturbance

2000 ◽  
Vol 80 (4) ◽  
pp. 633-647 ◽  
Author(s):  
C. M. Preston ◽  
J. A. Trofymow
Keyword(s):  
Tree Growth ◽  
Mineral Soil ◽  
Vancouver Island ◽  
Available P ◽  
Organic P ◽  
Coastal Forest ◽  
East Side ◽  
The West ◽  
West Side ◽  
Total P

Limitation of tree growth due to inadequate P supply has been found for young plantations following harvesting of old-growth in high rainfall areas of coastal British Columbia. To understand the reasons for P limitation, we investigated P chemistry in mineral soil to 50 cm depth in sites from the Coastal Forest Chronosequence project on Vancouver Island. This allowed comparison of biogeoclimatic subzone (higher rainfall on west than east coast sites) and of time from harvesting disturbance (seral stage). Available (Bray 1) P was significantly higher (P < 0.001) on the drier east side (up to 50 mg kg−1), than on the west side (<5 mg kg−1), although total P values were less divergent (694 mg kg−1, east and 534 mg kg−1, west). There were no significant seral stage effects on total and available P. Extraction with 0.5 M NaOH recovered 50–60% of total P, except for samples from 10–30 cm depth on the west side, for which only 20% was recovered, an effect not found for C. Analysis of the NaOH extracts by 31P nuclear magnetic resonance (NMR) spectroscopy showed much higher proportions of orthophosphate P on the east side. West side extracts were higher in organic P forms, especially diesters, typical of forest ecosystems with restricted nutrient cycling and high precipitation. On the west side, low concentrations of available P, higher proportions of organic P in NaOH extracts, and depression of NaOH extractability at 10–30 cm are consistent with P being a limiting nutrient for tree growth, a problem that may be exacerbated by harvesting disturbance. Key words: Forest chronosequences, harvesting disturbance, 31P NMR, P cycling, organic P

scholarly journals III.—Note on the Excavation of the Valleys in Derbyshire

1869 ◽  
Vol 6 (62) ◽  
pp. 347-348
Author(s):  
H. C. Sorby
Keyword(s):  
East Side ◽  
Considerable Time ◽  
The West ◽  
West Side ◽  
The Road ◽  
Surface Drainage ◽  
Main Valley ◽  
Subterranean Stream ◽  
Marked Surface

For a considerable time I have taken much interest in the question of the origin of the narrow and deep valleys in the Carboni-ferous Limestone district of Derbyshire, and have carefully recorded whatever seemed to explain their formation. So far I have never met with more striking facts than those to be seen in Deep Dale, about three miles in a direct line E.S.E. from Buxton. I estimate the depth of the valley at about 100 feet, and its width at from 100 to 200 yards. At a distance of about a mile from the Bakewell road there is a cavern, which is especially conspicuous on the east side. Its entrance is about 6 feet high, 20 feet broad, and 40 feet above the bottom of the valley. It extends nearly horizontally for about 30 yards, and then descends to a lower level, where I did not further examine it. On looking from the entrance to the opposite side of the dale I was surprised to see what appears to be a continuation of the same cavern. The entrance on that side is at about 80 feet above the valley, and is so much blocked up with detritus that one can only examine it for a space of 10 yards. Taking, however, all the facts into consideration, it appears to me that at a very remote period a subterranean stream flowed continuously along these two caverns, from west to east. There is abundance of suitable gather ground on the west side which even now has no well-marked surface drainage, and from which much of the water probably escapes by a subterranean course, ending in the large spring in the main valley, by the road-side below Kingsterndale.

Recent Changes in the Teifi Estuary

1925 ◽  
Vol 62 (5) ◽  
pp. 223-223
Author(s):  
M. P. Latter
Keyword(s):  
Opposite Direction ◽  
High Tide ◽  
River Channel ◽  
East Side ◽  
The West ◽  
West Side ◽  
The North ◽  
River Bed ◽  
Main River ◽  
Sand Flats

Within the last 50 years the lower reaches of the Teifi from St. Dogmells to Cardigan Bar have undergone a complete change: the bed of the river formerly lay near the west side of the estuary as far as the Webley Arms, and this point in the river was then known as Pwll Cam (“the crooked pool”), as it was here that the river took a sharp bend describing an ogee curve by way of the spit to the east of the present sandbanks: this old river channel lay in clay, unlike the present shallow river bed on the east side of the estuary, and quite big vessels could float even at low tide in front of the Webley Arms, which is now a low stretch of mud banks covered at high tide. A wreck, which laid up over two or three tides, was the simple means of effecting this change in the river's course. Since then it has led to other comparatively rapid geological changes: the Manian-fâch stream, which has its source in the Pant-y-Groes plateau, used to flow almost direct into the Teifi, when in its old course; now, however, since the bed of the Teifi, on leaving the Battery Point, crosses over to the east side of the estuary, the whole of the estuary to the west has been silted up with sand and mud, and this has been accelerated by the formation of sand-banks right across the mouth of the bay: consequently the Manian-fâch stream, on emerging off the mainland, is now deflected to the S.E. and flows for about a mile approximately parallel to the main river, though in the opposite direction, before joining it nearby the Battery Point. The watershed of the roughly triangular strip of sand flats, seen at low tide, lies very close to the present river bed, so that practically all the water off this area at low tide drains first into the Manian-fâch, and thus describes nearly a complete circle twice daily. This instance is analogous to, but not quite homologous with, that of the Eiver Aide in Suffolk, the original mouth of which has been deflected more than 12 miles south by currents from the north.

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