Paleoenvironmental context of archaeological sites,implications for subsistence strategies under Holocene climate change,northern Kenya

The Holocene was time of dramatic climate change in East Africa, shifting from wetter climate in the Early–Mid Holocene (∼10–5ka) to drier climates in the Late Holocene, followed by a slight reversal at <1ka. The Holocene was a time of cultural change from hunter‐gatherer and fishing to pastoralism. Recent excavations along the eastern shores of Lake Turkana, Kenya (4°N) provide new archaeological materials, a high‐resolution stratigraphic and paleoenvironmental data set, OSL dates, and cultural records in the context of documented environmental change (falling lake levels). Archaeological site FwJj25 (4.20 ± 0.28ka), on the northeastern margin of Lake Turkana, provides one of the earliest records of pastoralism in the region. The palimpsest record of FwJj5 (0.90 ± 0.06ka) was in a small valley containing a groundwater seep located 5km from the lake. FwJj5 reflects occupation by people who may have covered great distances in accessing resources, but were likely drawn to an environmental refugia of freshwater springs during times of regional aridity. © 2011 Wiley Periodicals, Inc.     

Enceladus: A hypothesis for bringing both heat and chemicals to the surface

The eruptive plumes and large heat flow (～15 GW) observed by Cassini in the South Polar Region of Enceladus may be expressions of hydrothermal activity inside Enceladus. We hypothesize that a subsurface ocean is the heat reservoir for thermal anomalies on the surface and the source of heat and chemicals necessary for the plumes. The ocean is believed to contain dissolved gases, mostly CO₂ and is found to be relatively warm (～0 °C). Regular tidal forces open cracks in the icy crust above the ocean. Ocean water fills these fissures. There, the conditions are met for the upward movement of water and the dissolved gases to exsolve and form bubbles, lowering the bulk density of the water column and making the pressure at its bottom less than that at the top of the ocean. This pressure difference drives ocean water into and up the conduits toward the surface. This transportation mechanism supports the thermal anomalies and delivers heat and chemicals to the chambers from which the plumes erupt. Water enters these chambers and there its bubbles pop and loft an aerosol mist into the ullage. The exiting plume gas entrains some of these small droplets. Thus, nonvolatile chemical species in ocean water can be present in the plume particles. A CO₂ equivalent-gas molar fraction of ～4 × 10^?4 for the ocean is sufficient to support the circulation. A source of heat is needed to keep the ocean warm at ～0 °C (about two degrees above its freezing point). The source of heat is unknown, but our hypothesis is not dependent on any particular mechanism for producing the heat.     

Ti diffusion in quartz inclusions: implications for metamorphic time scales

Quartz inclusions in garnet from samples collected from the staurolite zone in central New England are zoned in cathodoluminescence (CL). The CL intensity is interpreted to be a proxy for Ti concentration and the zoning attributed to Ti diffusion into the quartz grains driven by Ti exchange between quartz and enclosing garnet as a function of changing temperature. The CL zoning has been interpreted using a numerical diffusion model to constrain the time scales over which the diffusion has occurred. Temperature–time histories are sensitive to the presumed peak temperature but not to other model parameters. The total time of the metamorphic heating and cooling cycle from around 450?°C to the peak temperature (550–600?°C) back to 450?°C is surprisingly short and encompasses only 0.2–2 million years for peak temperatures of 600–550?°C. The metamorphism was accompanied by large-scale nappe and dome formation, and it is suggested that this occurred as a consequence of in-sequence thrusting resulting in a mid-crustal ductile duplex structure.     

Comparative Analysis and Assessment of Forest Landowner Typologies

Landowner typologies help researchers and practitioners understand similarities and differences among landowners, allowing more targeted education and communications. These typologies have rarely been rigorously assessed before recommended for use. We assessed three typologies created with one data set using three methods: reliability through split halves, predictive validity using external variables, and application of quality typology criteria. We conducted the work using a New York State landowner survey data set about early successional habitat management behavior. According to the assessment, none of the three typologies stood out as clearly the best—each had its strengths and weaknesses. The assessment provided a more complete understanding of different approaches and will allow researchers to be more informed when they select a typology to use to inform education and communications.     

Toward an Understanding and Definition of Wilderness Spirituality

There is an increasing body of Western literature lamenting the loss of spiritual relationships and connection with the Earth, and numerous studies of wilderness spirituality. But what is wilderness spirituality? Do expert perceptions differ from public views of the meaning of the term? This paper explores these questions. Despite spirituality being an abstract topic, and spiritual values hard to define and measure, numerous authors have suggested definitions of nature-based and wilderness spirituality. A content analysis of a random sample of the general population in a preliminary study in Tasmania on wilderness spirituality meanings was compared to definitions supplied by experts on the topic. Strong commonalities between the two groups were the citation of words expressing connection and interrelationship, portrayals of transcending the self, and the quality of compassion. Weak commonalties were terms such as ‘peace’ and ‘harmony’, ‘respect’, ‘joy’, ‘elation’, ‘happiness’, ‘sacredness’ and ‘reverence’. Disparate elements were found to be a sense of awe and wonder, religiosity, humbleness, and altered states of consciousness. The defining characteristics of wilderness spirituality were found to be a feeling of connection and interrelationship with other people and nature; a heightened sense of awareness and elevated consciousness beyond the everyday and corporeal world; and cognitive and affective dimensions of human understandings embracing peace, tranquillity, harmony, happiness, awe, wonder, and humility. A religious meaning and explanation may be present.     

Far-ultraviolet photometry of orion stars

Far-ultraviolet photometric data for early type stars in Orion, in the 1050–1180 and 1230–1350 Å wavelength ranges, were obtained in an Aerobee rocket flight on 30 January 1969. The results corrected for interstellar extinction, appear in good agreement with model atmospheres in the case of main-sequence stars. Bright giant and supergiant stars, however, appear to be up to one magnitude fainter than main-sequence stars of similar spectral class in the 1050–1180 Å range.The present results indicate that the detectors used in a previous flight were lower in sensitivity than was thought, so the results from that flight have been corrected using the present data for stars in common with the previous flight.The far-ultraviolet extinction law for Orionis is shown to be abnormal, with the observed extinction far less than predicted on the basis of ultraviolet extinction measurements of other stars, and the observedE(B-V).     

Geochemistry and age of metamorphosed felsic igneous rocks with A-type affinities in the Willyama Supergroup, Olary Block, South Australia, and implications for mineral exploration

Leucocratic quartzofeldspathic gneisses form a significant proportion of the lower part of the Palaeoproterozoic Willyama Supergroup sequence in the Olary Block, South Australia and have correlatives in the adjacent Broken Hill Block. Field and geochemical data demonstrate that these rocks were originally rhyolitic volcanics and granite, with A-type affinities consistent with magma production during intracratonic rifting, supporting tectonic models proposed for the Willyama Supergroup in the Broken Hill Block. Although the rocks have characteristic high-field-strength element enrichment, many have undergone extensive pervasive pre- or syn-metamorphic sodic alteration and are typically rich in albite.

Sensitive high resolution ion microprobe (SHRIMP) U-Pb zircon data tightly constrain the depositional and early intrusive history. Zircons from an interpreted metavolcanic rock containing relict quartz phenocrysts yield an age of 1699 ± 10 Ma, whereas a metagranitoid sample has an age of 1703 ± 6 Ma. These results are compatible with recent geochronological data on felsic metavolcanic rocks from the Broken Hill Block (Page and Laing, 1992) and are indicative of widespread magmatism during deposition of the Willyama Supergroup. Nd signatures for the two Olary Block samples imply the presence of a significant component from a depleted mantle source.

The A-type metavolcanic rocks are locally associated with small iron formations, some of which grade into stratiform barite-rich horizons. Although potentially favourable for sediment-hosted exhalative PbZn mineralisation, the Fe- and Ba-rich units, along with transgressive vein and breccia occurrences of Fe oxides ± quartz ± pyrite cutting both the metavolcanic and metagranitoid rocks, may be more prospective for epigenetic Cu-Au mineralisation related to later metamorphic and/or magmatic events. Partial melting of the A-type suite during high grade regional metamorphism at ˜ 1600 ± 20 Ma led to the formation of local volumes of sodic granitoids and pegmatites containing U-Th-Ti-REE-F mineralisation.     

Managing urban water systems with significant adaptation deficits—unified framework for secondary cities: part II—the practice

Adaptation gaps are shortcomings of a system responding to climate change, whereas adaptation deficits are shortcomings in providing services. These two drivers for adaptation are often in conflict in many secondary cities in the global south (SCGS). It is possible to align these seemingly conflicting drivers into a productive unity, a conceptual alignment, which is the first step in achieving harmony while implementing adaptation actions. This paper focuses on the practical aspects of implementing aligned adaptation action that leads to improvements in liveability, sustainability, and resilience of SCGS. At an abstract level, the nature of the adaptation problem is similar to the complex problems identified in various domains, such as software development, manufacturing, and supply chain management. The widely accepted “agile principles”—used in the above domains—is the basis for developing a set of twelve principles for urban adaptation, which are synthesized from numerous recent studies that have implicitly proposed or applied most of these principles to climate change adaptation in urban settings. These principles lead to four essential objectives appertaining to the process of sustainable urban adaptation. The urban agile principles are used to analyze the current state of adaptation of Can Tho City in Vietnam and to ascertain the agile ways of addressing its adaptation challenges. Analysis of the outcomes shows that harmonized approaches can simultaneously address both adaptation deficits and gaps.