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61.
《The Professional geographer》2012,64(1):78-87
Q methodology combines qualitative and quantitative approaches to measure subjectivity by identifying shared worldviews among participants. Since Q methodology was first introduced to human geography by Robbins and Krueger (2000), a nascent body of “critical Q” research has emerged among researchers who employ Q methodology in critical, reflexive, and innovative ways. In particular, this body of work questions the positivist foundations of standard Q methodology as a supposedly “objective” measure of subjectivity. Although many such analyses use Q methodology to identify and analyze discourses, few explicitly engage the field of critical discourse analysis. This article argues that discourse analysis has been “blackboxed” in geographic Q scholarship and outlines four key moments in the standard Q methodology protocol where researchers could productively integrate critical discourse analysis. In so doing, this article argues that juxtaposing the “messiness” of critical discourse analysis and the “tidiness” of Q methodology exposes productive tensions, gaps, and contradictions that provide key moments for interrogation and critical reflexivity. Key Words: discourse analysis, mixed methods, Q methodology, reflexivity subjectivity. 相似文献
62.
《The Professional geographer》2012,64(1):96-108
Manuel Castells seminal work The Rise of the Network Society (RNS) is one of the top ten most frequently cited publications in human geography. RNS comprehensively investigates the theory of network society, which is of great significance to human geography. Citation count, however, cannot reflect the specific contribution of RNS to human geography. By jointly using citation content and context analysis on 898 journal articles on human geography, this study examines the citations of RNS to clarify the contribution. Results show that (1) “space of flows” is most frequently cited and (2) citations of RNS serve nine citation functions in human geography studies. Eight of them reveal three types of knowledge development contribution, namely, knowledge dissemination, knowledge inheritance, and knowledge innovation. Among the nine citation functions, the critique function is most thought-provoking, revealing the deficiencies of RNS: (1) spatial dualism is abstract and impersonal, (2) “space of places” is as important as “space of flows” in the network society, and (3) the lack of abundant data limits the development of empirical research on the space of flows and network of city. These critical citations provide implications for the development of network society theory in human geography. Key Words: bibliometric analysis, citation context analysis, content analysis, knowledge development, network society. 相似文献
63.
《The Professional geographer》2012,64(1):139-151
Past occupations in the Brazilian geographic area showed experiences of particular relations with natural resources. In this sense, landscape archaeology attempts to have a better understanding of the lifestyle of ancestral populations by analyzing archaeological traces. The study approach that translates the natural systems and their relations with the anthropic systems is known as geosystem theory, which helps landscape archaeology in patterns of past occurrences resulting from environmental characteristics. The objective of this study was to show the geosystem landscapes of Ilhéus, in Bahia, Brazil, that defined land occupation since the precolonial period in Brazil. Four geosystems have been identified; they defined how precolonial groups lived in the area and favored colony growth starting in the nineteenth century with local sugarcane production in sugarcane mills. Key Words: geoarchaeology, GIS, natural systems, northeastern Brazil. 相似文献
64.
Juan Reynerio Fagundo-Castillo Joel José Carrillo-Rivera Iñaki Antigüedad-Auzmendi Patricia González-Hernández Roberto Peláez-Díaz Rebeca Hernández-Díaz Dámaso Cáceres-Govea José Ramón Hernández-Santana Margaret Suárez-Muñoz Clara Melián-Rodríguez Mónica Rodríguez-Piña 《Environmental Geology》2008,55(2):247-267
Flows of different hierarchy, which travel through limestone, schist, sandstone and ultra-basic rocks, with ages from the
Paleocene to the Jurassic, at Sierra del Rosario, Pinar del Río, Cuba, were characterized. The waters were sampled from 1984
until 2004 and the data were statistically processed by means of chemical equilibrium and physico-chemical models, under a
flow system view of interpretation. Results demonstrate that the physico-chemical properties of the water are controlled by
water–rock interaction resulting from residence time since rainwater infiltrate and the path it follows to the discharge zone
and the type of aquifer material the different groundwater flows are in contact with. Geochemical indices allow the definition
of the different types of flow (local, intermediate, regional) to be characterized, permitting a further definition of the
different flow systems and rock type involved, as well as its use for water supply and medical use. The main geochemical processes
which control the chemical composition acquisitions mode are: congruent dissolution of calcite, dolomite, and halite; incongruent
dissolution of plagioclase and microcline minerals; pyrite oxidation, sulphate reduction, and silica dissolution at the surface
or silica precipitation at deep saturation and circulation zones. 相似文献
65.
66.
Here we present archosauriform remains from ‘Abra de los Colorados’, a fossiliferous locality at Sierra de Guayaguas, NW San Luis Province. Two fossiliferous levels were identified in outcrops of the Quebrada del Barro Formation (Norian), which represent the southernmost outcrops of the Marayes–El Carrizal Basin. These levels are composed by massive muddy lithofacies, interpreted as floodplain deposits. The specimens consist of one incomplete maxilla (MIC-V718), one caudal vertebra (MIC-V719), one metatarsal (MIC-V720) and one indeterminate appendicular bone (MIC-V721). The materials can be assigned to Archosauriformes but the fragmentary nature and lack of unambiguous synapomorphies preclude a more precise taxomic assignment. The maxilla is remarkably large and robust and represents the posterior process. It preserved one partially erupted tooth with ziphodont morphology. This bone shows some anatomical traits and size match with ‘rauisuchians’ and theropods. MIC-V719 corresponds to a proximal caudal vertebra. It has a high centrum, a ventral longitudinal furrow, expanded articular processes for the chevrons, a posteriorly displaced diapophysis located below the level of the prezygapophyses, and short prezygapophyses. This vertebra would be from an indeterminate archosauriform. MIC-V720 presents a cylindrical diaphysis, with a well-developed distal trochlea, which present resemblances with metatarsals of theropods, pseudosuchians, and silesaurids, although the size matches better with theropods. MIC-V721 has a slender diaphysis and a convex triangular articular surface, and corresponds to an indeterminate archosauriform. Despite being fragmentary, these materials indicate the presence of a diverse archosauriforms association from Late Triassic beds of San Luis. Thus, they add to the faunal assemblage recently reported from this basin at San Juan Province, which is much rich and diverse than the coeval paleofauna well known from Los Colorados Formation in the Ischigualasto–Villa Union Basin. 相似文献
67.
C. Schaeffer-Reiss P. Schaeffer A. Putschew J. R. Maxwell 《Organic Geochemistry》1998,29(8):1857-1873
Stepwise chemical degradation involving cleavage of ester bonds (KOH/MeOH), sulfide and remaining ester bonds (Li/EtNH2), ether bonds (HI/LiAlH4) and sub-units linked to aromatic moieties (RuO4) has been carried out on the kerogens of two immature sulfur-rich marls (IV-1.4 and 1.8, TOC ca. 1.5%) from evaporitic cycle IV of the Gesosso-solfifera Formation (Messinian, Vena del Gesso, Italy). Up to 80% of the organic matter was converted to solvent-soluble material, with the greatest proportion released by Li/EtNH2. The majority by far of the extracts comprises polar macromolecular material which is thought to correspond to high molecular weight sub-units of the kerogen. Quantification of the small amounts (<1%) of the released GC-amenable components indicates that diagenetic sulfurization was more important in the case of kerogen IV-1.4 but that the extent of oxygen sequestration was similar in both cases; the distributions of biomarkers released by ether cleavage of the desulfurized residue and polar fraction showed differences which reveal heterogeneity in the building blocks making up different macromolecular fractions. 相似文献
68.
Juan Jos Ponce Eduardo B. Olivero Daniel R. Martinioni 《Journal of South American Earth Sciences》2008,26(1):36-54
The Upper Oligocene–Miocene deposits of the foreland Austral Basin of Tierra del Fuego represent the youngest foredeep fill, developed in front of the adjacent fold and thrust belt. They consist of superbly exposed, sub-horizontal clastic successions of more than 600 m of sedimentary thickness. The study of 11 sections by means of facies analysis and sequence stratigraphic criteria enabled the identification of five depositional sequences (SI–SV), bounded by unconformities (dI-dV) involving hiatuses of different magnitudes. The basal sequence (SI) includes two members: A, mudstone dominated, deposited by cohesive flows; and B, glauconite-rich, sandstone dominated, deposited by episodic turbidity currents. The remaining sequences (SII–SV) are composed of complex arrangements of fine conglomerates, coarse- to fine-grained sandstones, and mudstones that were deposited mainly by hyperpycnal flows. The basal unconformities of the SI to SIV involve minor hiatuses, while that of the SV is a major order unconformity. Two types of clinofom geometries are recognized in the foredeep sequences. Type a clinoforms present a wedge shaped geometry and characterize the foredeep infill during the compressional tectonic regime. Regarding this clinoform type, SI is situated closer to the orogen and shows variations in the bedding dip with development of internal unconformities. SII to SIV are situated towards the foreland and are characterized by subhorizontal conformable beds of large lateral extension. Type b clinoforms, with sigmoidal geometry, show a clear northeast progradation related to a progressive foredeep fill under tectonic quiescence. This clinoform type characterizes the deposits in SV. The recognition of hyperpycnites and different types of clinoform geometries in these sequences incorporates new concepts in reservoir prospects, which are critical for the evaluation of the petroleum system in the Austral Basin. 相似文献
69.
Subtidal sediments of Isla del Coco(Cocos Island),Costa Rica were described in their grain size,sorting,organic matter,and carbonates from 27 dredge samples(3-75 m),collected in April 2010.The organic matter range between 1.37-3.31%and carbonates presented a mean of 74±17%.The sorting was moderately or poorly.The grain size ranged between 0.1-1.1mm.The pattern is that sediment change from inner to mouth of bays.Carbonates and gravel fractions increased offshore and organic matter have high values inner the bays.Input of vegetal debris and mud was from the rivers of this island covered with rain and cloud forest. 相似文献
70.
《Geofísica Internacional》2014,53(4):411-423
An investigation of the effect of some human activities on the magnetic susceptibility and frequency dependent susceptibility was conducted on top soil samples from, a commercial area, a motor park and a school environment in Jalingo, Taraba State, N-E Nigeria. The purpose was to assess the variation of magnetic susceptibility with different land use, detect pollution hotspots using magnetic proxy parameters and evaluate the contribution of superparamagnetic (SP) grain size contribution to the magnetic susceptibility from calculation of the frequency dependence of magnetic susceptibility (MS). The results of the mass specific low frequency magnetic susceptibility measurements showed significant enhancement with values ranging from 67.8 − 495.3 × 10−8 m3kg−1 with a mean value of 191.61 × 10−8 × m3kg−1 for the Jalingo College of Education (JCOE) data; 520.1 − 1612.8 × 10−8 m3kg−1 with a mean value of 901.34 × 10−8 m3kg−1 for the Jalingo main Market (JMM) and 188.5 − 1203.6 × 10−8m3kg−1 with an average value of 574 92 × 10−6 m3kg−1 for the Jalingo Motor Park (JMP). The significant magnetic enhancement indicates high concentration of ferrimagnetic minerals in the soil and hence increased pollution. The magnetic susceptibility of the different land use studied decreased in the order commercial area (market) > motor park > school premises. The results of the percentage frequency dependence susceptibility showed that most of the samples had a mixture of SP and coarse multi domain grains or SP grains < 0.05 µm. The value of χfd% range from 2.68 to 13.80% with an average value of 8.67% in the JCOE samples, 0.49 to 10.04% with an a-verage of 5.05% in the JMM samples and 0.56 to 13.04% with an average value of 5.86% in the JMP samples. 相似文献