The Intermontane Western Tradition

1962 ◽  
Vol 28 (2) ◽  
pp. 144-150 ◽  
Author(s):  
Richard D. Daugherty

AbstractThe hypothesis of an Intermontane Western tradition is advanced as a conceptual framework within which it is possible to achieve a greater understanding of the cultural histories of the Plateau, Great Basin, and Southwest culture areas, including broad and specific relationships and also the developing differences.Geographically, the Intermontane Western tradition extended throughout the intermontane region between the Cascade-Sierra Nevada ranges on the west, and the Rocky Mountains on the east, and from southern British Columbia on the north to northern Mexico on the south. Temporally, the Intermontane Western tradition existed throughout the post-glacial period.Within the major tradition, the Southwest Agricultural, Desert, and Northwest Riverine Areal traditions are seen developing, partly in response to environmental changes.

2020 ◽  
Author(s):  
George P Malanson ◽  
Dale L Zimmerman ◽  
Daniel B Fagre

The floras of mountain ranges, and their similarity, beta diversity, and endemism, are indicative of processes of community assembly; they are also the initial conditions for coming disassembly and reassembly in response to climate change. As such, these characteristics can inform thinking on refugia. The published floras or approximations for 42 mountain ranges in the three major mountain systems (Sierra-Cascades, Rocky Mountains, and Great Basin ranges) across the western USA and southwestern Canada were analyzed. The similarity is higher among the ranges of the Rockies while equally low among the ranges of the Sierra-Cascades and Great Basin. Mantel correlations of similarity with geographic distance are also higher for the Rocky Mountains. Endemism is relatively high, but is highest in the Sierra-Cascades (due to the Sierra Nevada as the single largest range) and lowest in the Great Basin, where assemblages are allochthonous. These differences indicate that the geologic substrates of the Cascade volcanoes, which are much younger than any others, play a role in addition to geographic isolation in community assembly. The pattern of similarity and endemism indicates that the ranges of the Cascades will not function well as stepping stones and the endemic species that they harbor may need more protection than those of the Rocky Mountains. The geometry of the ranges is complemented by geology in setting the stage for similarity and the potential for refugia across the West. Understanding the geographic template as initial conditions for the future can guide the forecast of refugia and related monitoring or protection efforts.


1980 ◽  
Vol 70 (5) ◽  
pp. 1557-1572
Author(s):  
J. D. VanWormer ◽  
Alan S. Ryall

abstract Precise epicentral determinations based on local network recordings are compared with mapped faults and volcanic features in the western Great Basin. This region is structurally and seismically complex, and seismogenic processes vary within it. In the area north of the rupture zone of the 1872 Owens Valley earthquake, dispersed clusters of epicenters agree with a shatter zone of faults that extend the 1872 breaks to the north and northwest. An area of frequent earthquake swarms east of Mono Lake is characterized by northeast-striking faults and a crustal low-velocity zone; seismicity in this area appears to be related to volcanic processes that produced thick Pliocene basalt flows in the Adobe Hills and minor historic activity in Mono Lake. In the Garfield Hills between Walker Lake and the Excelsior Mountains, there is some clustering of epicenters along a north-trending zone that does not correlate with major Cenozoic structures. In an area west of Walker Lake, low seismicity supports a previous suggestion by Gilbert and Reynolds (1973) that deformation in that area has been primarily by folding and not by faulting. To the north, clusters of earthquakes are observed at both ends of a 70-km-long fault zone that forms the eastern boundary of the Sierra Nevada from Markleeville to Reno. Clusters of events also appear at both ends of the Dog Valley Fault in the Sierra west of Reno, and at Virginia City to the east. Fault-plane solutions for the belt in which major earthquakes have occurred in Nevada during the historic period (from Pleasant Valley in the north to the Excelsior Mountains on the California-Nevada Border) correspond to normaloblique slip and are similar to that found by Romney (1957) for the 1954 Fairview Peak shock. However, mechanisms of recent moderate earthquakes within the SNGBZ are related to right- or left-lateral slip, respectively, on nearly vertical, northwest-, or northeast-striking planes. These mechanisms are explained by a block faulting model of the SNGBZ in which the main fault segments trend north, have normal-oblique slip, and are offset or terminated by northwest-trending strike-slip faults. This is supported by the observation that seismicity during the period of observation has been concentrated at places where major faults terminate or intersect. Anomalous temporal variations, consisting of a general decrease in seismicity in the southern part of the SNGBZ from October 1977 to September 1978, followed by a burst of moderate earthquakes that has continued for more than 18 months, is suggestive of a pattern that several authors have identified as precursory to large earthquakes. The 1977 to 1979 variations are particularly noteworthy because they occurred over the entire SNGBZ, indicating a regional rather than local cause for the observed changes.


1959 ◽  
Vol 91 (4) ◽  
pp. 232-242 ◽  
Author(s):  
C. D. Dondale

Grammonota Emerton, 1882, is one of the many uniform genera that constitute the large and complex family Erigonidae. All of the 28 species and one subspecies recognized by the present writer are American in range, and representatives occur from southwestern Alaska and James Bay in the north to Central America and the West Indies. A few species are arctic-alpine, or are restricted to the Pacific coast, but most occur east of the Rocky Mountains from southern Canada to the Gulf States.


2008 ◽  
Vol 70 (2) ◽  
pp. 131-140 ◽  
Author(s):  
Glen M. MacDonald ◽  
Katrina A. Moser ◽  
Amy M. Bloom ◽  
David F. Porinchu ◽  
Aaron P. Potito ◽  
...  

AbstractSediment records from two lakes in the east-central Sierra Nevada, California, provide evidence of cooling and hydrological shifts during the Younger Dryas stade (YD; ~ 12,900–11,500 cal yr BP). A chironomid transfer function suggests that lake-water temperatures were depressed by 2°C to 4°C relative to maximum temperatures during the preceding Bølling–Allerød interstade (BA; ~ 14,500–12,900 cal yr BP). Diatom and stable isotope records suggest dry conditions during the latter part of the BA interstade and development of relatively moist conditions during the initiation of the YD stade, with a reversion to drier conditions later in the YD. These paleohydrological inferences correlate with similar timed changes detected in the adjacent Great Basin. Vegetation response during the YD stade includes the development of more open and xeric vegetation toward the end of the YD. The new records support linkages between the North Atlantic, the North Pacific, and widespread YD cooling in western North America, but they also suggest complex hydrological influences. Shifting hydrological conditions and relatively muted vegetation changes may explain the previous lack of evidence for the YD stade in the Sierra Nevada and the discordance in some paleohydrological and glacial records of the YD stade from the western United States.


2019 ◽  
Vol 62 (2) ◽  
pp. 197-246
Author(s):  
Claudia Finkler ◽  
Kalliopi Baika ◽  
Diamanto Rigakou ◽  
Garyfalia Metallinou ◽  
Peter Fischer ◽  
...  

Ancient Corcyra (modern Kerkyra or Corfu) was an important harbour city and commercial centre since the Archaic period, also due to its geostrategic position on the trade routes between Greece and Italy or Sicily. Corcyra kept its status as one of the prevailing naval powers in the Mediterranean by means of a large naval fleet, needing appropriated harbour basins to be stored and repaired. At least two harbours are documented by historical records and associated archaeological remains, namely the Alkinoos and the Hyllaikos Harbours, both located on either side of a narrow isthmus to the north of the Analipsis Peninsula, where the ancient polis developed. Today, the ancient harbour basins are silted and overbuilt by modern urban infrastructure, concealing their overall extent and topography. The present study aims to reconstruct the complex palaeogeographies of the ancient Alkinoos harbour of Corcyra based on a multi-methodological palaeoenvironmental and geoarchaeological approach. The methods used include sedimentary, geochemical, microfaunal and geophysical investigations that were complemented by archaeological data and results from previous geoarchaeological research. Spatially, the study focusses on the area of the so-called Desylla site west of known Alkinoos Harbour sediments in the midst of the modern city of Corfu. These results were complemented by findings from two geomorphological key sites as well as archaeoseismological traces from the western part of the Analipsis Peninsula. At the Desylla site, we found sedimentary evidence of an Archaic pre-harbour, partly open to the Gulf of Corfu, which was the predecessor of a protected Classical harbour basin. This basin, in use between at least the 4th to 3rd cent. BC and the 1st cent. AD, was delimited to the west by a wall. It represents the central part of the Classical Alkinoos Harbour which was sedimentologically traced, for the first time, from the De- sylla site in the west to the Kokotou site in the east, where monumental shipsheds were unearthed during earlier archaeological excavations. Probably, the harbour zone extended even further to the east, where contemporaneous harbour deposits were found associated with the prominent quay wall at the Pierri and Arion sites. Our results show, that, apart from man-made interventions, Corcyra's palaeogeographical evolution is strongly linked to multiple impacts of extreme wave events in the form of tsunami inundation. At least four events (I–IV) are recorded in the natural geoarchives of the Analipsis Peninsula and its surroundings as well as the northern harbour zone of ancient Corcyra. In particular, these events happened between 5600 and 5200 cal BC (event I), after 3900 cal BC (event II), between the 4 th and 3 rd cent. BC (event III) and between the 3 rd and 6 th cent. AD, most likely at 365 AD (event IV). Ages of all events correlate well with ages of tsunami traces found on Sicily, the Greek mainland and other Ionian Islands. Tsunami events I and II led to massive environmental changes around the Analipsis Peninsula, while event III was associated to strong co-seismic uplift, leading to the abandonment of the harbour site at Pierri. Decreasing water depths by siltation of the Kokotou and Desylla sites, however, were redressed by dredging, giving rise to an extensive Roman re-use of the western part of the Alkinoos Harbour zone. Yet, both harbour sites were hit again by event IV filling the harbour basins by a thick sequence of event deposits.


The Geologist ◽  
1863 ◽  
Vol 6 (5) ◽  
pp. 168-178
Author(s):  
William King

The classification given in the sequel is based on the following premises:—1st. The entire area of the British Isles has undergone at different times, during the Glacial and Post-Glacial periods, a succession of secular elevating and subsiding movements.2nd. At the close of the Pliocene period, the relative level of land and sea over the British area was approximately the same as at present.3rd. The edge of the two-hundred-fathoms submarine plateau, on the east side of the North Atlantic, formed the west coast-line of a continent (now represented by Europe) during the earliest time (epoch) of the Glacial period.4th. The climate of the British area was frigid in the extreme during the Glacial period, allowing epochs of amelioration.5th. Rock-surfaces undergo enormous degradation when they are above the sea-level, during the prevalency of glaciation.


Author(s):  
Earl B. Alexander ◽  
Roger G. Coleman ◽  
Todd Keeler-Wolfe ◽  
Susan P. Harrison

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.


Zootaxa ◽  
2020 ◽  
Vol 4819 (2) ◽  
pp. 349-363
Author(s):  
P. PAQUIN ◽  
N. DUPÉRRÉ ◽  
D.J. BUCKLE ◽  
D. UBICK

The genus Oaphantes is known from the West Coast of North America. Here we revise the genus which now includes three species, two of which are new: O. cryophilus n. sp. and O. prometheus n. sp. All Members of the genus Oaphantes show affinities for cave habitats. Oaphantes pallidulus is known from caves of the Coast Ranges of California and also from epigean records. Oaphantes cryophilus n. sp. is restricted to caves in the southern limit of its distribution in the Sierra Nevada Mountains of California, but in the north it is known from epigean records in Oregon, Washington and British Columbia. Oaphantes prometheus n. sp. is an eyeless troglobite endemic to a single cave in the Sierra Nevada of California. The distribution and relationships of the three species suggest an evolutive scenario likely due to climatic variations and affinities for colder conditions.


1970 ◽  
Vol 35 ◽  
pp. 77-111 ◽  
Author(s):  
Richard G. Klein

Prehistorians concerned with the Pleistocene have traditionally defined their cultural units (‘industries’) mainly by the types of stone artefacts they contain. One of the best known of these units is the Mousterian, authoritatively defined by Francois Bordes (1953, 458) as ‘… an industry of flakes, comprising a variable proportion of side-scrapers, points, denticulate tools, and also bifaces. Technically, the flakes may or may not be of Levallois débitage and may or may not have faceted butts, Levallois débitage and butt-faceting having no necessary relation to one another’. The Mousterian is generally assumed to have its roots in an earlier group of industries known as the Acheulean. It is difficult to determine when the Mousterian emerged as a distinct entity both because differentiation from the Acheulean occurred only gradually and because our geochronological controls are imperfect. Certainly, however, the Mousterian was in existence by the beginning of the Last ( = ‘Würm’) Glacial Period, that is, no later than 65,000–70,000 years ago (Table I). In the earlier part of this Glacial, it was distributed from the Iberian Peninsula on the west to Uzbekistan (and perhaps beyond) on the east, and from the British Isles on the north to the Mediterranean littoral of Africa on the south. Sometime between 40,000 and 30,000 years ago (the exact time perhaps depending upon the place), the Mousterian was rather abruptly replaced over most, if not all of this range. The demise of the Mousterian is of especial interest because there is considerable evidence to suggest that it was intimately connected with the disappearance of Neandertal Man (Homo sapiens neanderthalensis) and the subsequent spread of modern man (Homo sapiens sapiens).


1955 ◽  
Vol 62 (3) ◽  
pp. 769-928 ◽  
Author(s):  
J. K. Charlesworth

SynopsisFrom the abounding moraines, drainage features (fig. 21) and other marginal indications an attempt has been made to reconstruct the successive phases of the ice in its retreat into the corries of the Highlands and Islands (Pl. I). Two late-glacial stages are recognised. During the first, the Highland Glaciation, an ice-margin ran from the Orkney Islands across the mouth of the Moray Firth to the Buchan and out to sea north of Aberdeen. Twelve substages (A–L) of retreat, arbitrarily selected, have been traced through the country, except in the Moraineless West where they are unrepresented.At the maximum of the second stage, the Moraine Glaciation, the ice readvanced to the line stage M (beaded line in Pl. I). The retreat from this line, the inner boundary of the Moraineless West and of the 100-foot raised beach (Pl. I), is divided into nine substages (N–V), based upon a consideration of snowlines. Substage N corresponds to the 50-foot raised beach, substage P to an important readvance.The snowline throughout the late-glacial period ran in the west parallel with the meridians and rose eastwards. The disposition of the snowlines for stage M is given in fig. 22, p. 900.The distribution of the ice in the British Isles during the North British, Highland and Moraine Glaciations is represented in fig. 23, p. 923.


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