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| 2. |
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| 3. |
- Lidén, Magnus, Docent, 1951-
(author)
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193 and 246 of Philosophia botanica do not support that Linnaeus was a "typologist"
- 2020
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In: Taxon. - : WILEY. - 0040-0262 .- 1996-8175. ; 69:2, s. 213-216
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Journal article (other academic/artistic)abstract
- 193 and 246 of Linnaeus's Philosophia botanica have recently been invoked to suggest that Linnaeus used, or even introduced, the "Method of Type", which implies that a genus is centred around a "typical" species. However, there is no support for this conclusion in either of the two paragraphs, rather the opposite. A recapitulation of the last twenty years' reassessment of Linnaeus's taxonomic philosophy is given.
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| 5. |
- Chirumalla, Koteshwar, Associate Professor, et al.
(author)
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Enabling battery circularity : Unlocking circular business model archetypes and collaboration forms in the electric vehicle battery ecosystem
- 2024
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In: Technological forecasting & social change. - : Elsevier Inc.. - 0040-1625 .- 1873-5509. ; 199
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Journal article (peer-reviewed)abstract
- Achieving battery circularity is crucial for meeting the targets of net-zero emission vehicles by 2030 and enabling climate-neutral transportation by 2050. To facilitate this transition, firms operating in the electric vehicle (EV) battery ecosystem must reassess their value creation, capture, and delivery methods. Although EV battery second life presents a promising solution for circularity, many vehicle manufacturers and stakeholders in the battery ecosystem struggle to adapt their organizations internally and externally due to a lack of insights into suitable circular business models. The purpose of this study is to identify viable archetypes of circular business models for EV battery second life and examine their implications on company collaborations within the EV battery ecosystem. Three main archetypes of circular business models are identified (i.e., extending, sharing, and looping business models) and further divided into eight sub-archetypes. These models are elucidated in terms of key business model dimensions, including value proposition, value co-creation, value delivery, and value capture. The paper provides visual representations of the necessary interactions and collaborations among companies in the EV battery ecosystem to effectively implement the proposed business model archetypes. This research contributes to the theory of circular business models in general, with specific relevance to EV battery circularity.
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| 6. |
- Ekström, Magnus Pär, et al.
(author)
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The association of body mass index, weight gain and central obesity with activity-related breathlessness : the Swedish Cardiopulmonary Bioimage Study
- 2019
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In: Thorax. - : BMJ Publishing Group Ltd. - 0040-6376 .- 1468-3296. ; 74:10, s. 958-964
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Journal article (peer-reviewed)abstract
- Introduction: Breathlessness is common in the population, especially in women and associated with adverse health outcomes. Obesity (body mass index (BMI) >30 kg/m(2)) is rapidly increasing globally and its impact on breathlessness is unclear.Methods: This population-based study aimed primarily to evaluate the association of current BMI and self-reported change in BMI since age 20 with breathlessness (modified Research Council score >= 1) in the middle-aged population. Secondary aims were to evaluate factors that contribute to breathlessness in obesity, including the interaction with spirometric lung volume and sex.Results: We included 13 437 individuals; mean age 57.5 years; 52.5% women; mean BMI 26.8 (SD 4.3); mean BMI increase since age 20 was 5.0 kg/m(2); and 1283 (9.6%) reported breathlessness. Obesity was strongly associated with increased breathlessness, OR 3.54 (95% CI, 3.03 to 4.13) independent of age, sex, smoking, airflow obstruction, exercise level and the presence of comorbidities. The association between BMI and breathlessness was modified by lung volume; the increase in breathlessness prevalence with higher BMI was steeper for individuals with lower forced vital capacity (FVC). The higher breathlessness prevalence in obese women than men (27.4% vs 12.5%; p<0.001) was related to their lower FVC. Irrespective of current BMI and confounders, individuals who had increased in BMI since age 20 had more breathlessness.Conclusion: Breathlessness is independently associated with obesity and with weight gain in adult life, and the association is stronger for individuals with lower lung volumes.
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| 7. |
- Engström, Carl-Peter, 1945, et al.
(author)
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Functional status and well being in chronic obstructive pulmonary disease with regard to clinical parameters and smoking: a descriptive and comparative study.
- 1996
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In: Thorax. - 0040-6376. ; 51:8, s. 825-30
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Journal article (peer-reviewed)abstract
- BACKGROUND: Self-assessment questionnaires which measure the functional and affective consequences of chronic obstructive pulmonary disease (COPD) give valuable information about the effects of the disease and may serve as important tools with which to evaluate treatment. METHODS: A cross sectional comparative study was performed between patients with COPD (n = 68), stratified according to pulmonary function, and a healthy control group (n = 89). A battery of well established clinical and quality of life measures (the Sickness Impact Profile (SIP), Mood Adjective Check List (MACL), and Hospital Anxiety and Depression scale (HAD)) was used to examine in which functional and affective aspects the patient group differed from the control group and how these measures related to pulmonary function and smoking habits. RESULTS: Compared with the controls, COPD affected functional status in most areas, not just those requiring physical activity. Forty six patients with forced expiratory volume in one second (FEV1) below 50% predicted showed particularly high levels of dysfunction in ambulation, eating, home management, and recreation/ pastimes (SIP). Despite this, their level of psychosocial functioning and mood status was little different from that of the healthy controls. Among the patients, a subgroup reported substantial psychological distress, but mood status was only weakly, or not at all, related to pulmonary function. Smoking habits did not affect functional status or well being. CONCLUSIONS: Quality of life is not significantly affected in patients with mild to moderate loss of pulmonary function, possibly due to coping and/or pulmonary reserve capacity. This suggests that generic self-assessment questionnaires are of limited value for detecting the early consequences of COPD. However, in later stages of the disease they are sensitive enough to discriminate between patients with different levels of pulmonary dysfunction. The low correlations between the indices of pulmonary function and the indices of affective status suggest that well being depends, to a large extent, on factors outside the clinical domain.
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| 9. |
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| 10. |
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| 11. |
- Pesonen, LJ, et al.
(author)
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Palaeomagnetic configuration of continents during the Proterozoic
- 2003
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 375:1-4, s. 289-324
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Research review (peer-reviewed)abstract
- Palaeomagnetic data are used to study the configurations of continents during the Proterozoic. Applying stringent reliability criteria, the positions of the continents at 12 times in the 2.45- to 1.00-Ga period have been constructed. The continents lie predominantly in low to intermediate latitudes. The sedimentological indicators of palaeoclimate are generally consistent with the palaeomagnetic latitudes, with the exception of the Early Proterozoic, when low latitude glaciations took place on several continents. The Proterozoic continental configurations are generally in agreement with current geological models of the evolution of the continents. The data suggest that three large continental landmasses existed during the Proterozoic. The oldest one is the Neoarchaean Kenorland, which comprised at least Laurentia, Baltica, Australia and the Kalahari craton. The protracted breakup of Kenorland during the 2.45- to 2.10-Ga interval is manifested by mafic dykes and sedimentary rift-basins on many continents. The second 'supercontinental' landmass is Hudsonland (also known as Columbia). On the basis of purely palaeomagnetic data, this supercontinent consisted of Laurentia, Baltica, Ukraine, Amazonia and Australia and perhaps also Siberia, North China and Kalahari. Hudsonland existed from 1.83 to ca. 1.50-1.25 Ga. The youngest assembly is the Neoproterozoic supercontinent of Rodinia, which was formed by continent-continent collisions during similar to 1.10-1.00 Ga and which involved most of the continents. A new model for its assembly and configuration is presented, which suggests that multiple Grenvillian age collisions took place during 1.10-1.00 Ga. The configurations of Kenorland, Hudsonland and Rodinia depart from each other and also from the Pangaea assembly. The tectonic styles of their amalgamation are also different reflecting probable changes in sizes and thicknesses of the cratonic blocks as well as changes in the thermal conditions of the mantle through time. (C) 2003 Elsevier B.V. All rights reserved.
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| 12. |
- Ask, Maria, et al.
(author)
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Ocean-continent boundary in the Iberia Abyssal Plain from multichannel seismic data
- 1993
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 218:4, s. 383-393
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Journal article (peer-reviewed)abstract
- The Ocean-Continent Boundary of the West Iberia margin is marked by a basement ridge trending N-S. Four segments of this ridge are recognized, each of them being progressively offset westward from 40°N to 43°N. Because the setting and seismic character of the ridge in the Iberia Abyssal Plain are similar to those of the Galicia margin ridge, which is made of serpentinized peridotite, we think that the southern segments of the ridge are also made of the same mantle material. The segmentation of the ridge suggests that the northward propagation of the continental break-up during the North Atlantic opening in Early Cretaceous times was discontinuous, each segment possibly corresponding to a propagation step. East of the ridge, the basement of the whole Iberia Abyssal Plain consists of highly thinned continental crust locally resting on a seismic reflector that resembles the S reflector previously recognized off Galicia. By analogy with the Galicia margin, we propose that the tilted crustal blocks lay on serpentinized peridotite derived from the upper mantle, the S reflector corresponding to the contact between crustal rocks and serpentinite.
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| 13. |
- Bastida, F, et al.
(author)
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A cross-section through the Zilair Nappe (southern Urals)
- 1997
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In: Tectonophysics. - : Elsevier. - 0040-1951 .- 1879-3266. ; 276:1-4, s. 253-263
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Journal article (other academic/artistic)abstract
- A structural transect in the Zilair-Kugarchi area involves the western part of the Suvanyak Complex, the Zilair Nappe and the eastern part of the foreland thrust and fold belt. This section has been analyzed using field, microstructural and seismic data. The cross-section shows the transition from the hinterland to the foreland in the footwall to the suture of the southern Urals. The rocks involved range from early Palaeozoic to Permian in age. A characteristic of the Zilair Nappe is the dominance of a succession of volcanic greywackes and mudrocks of Late Devonian age (Zilair Formation). The metamorphic grade decreases from east to west, from greenschist facies to diagenetic conditions. The structure of the cross-section mainly comprises west-directed thrusts and thrust-related folds with an associated cleavage. Fold vergence changes along the section depending on of the distance to the associated thrust and its geometry. The Zilair thrust which separates the Zilair Nappe from the foreland thrust and fold belt accommodated ca. 10 km displacement and the characteristics of the deformation are similar on both sides of it. The contact between the Zilair Nappe and Suvanyak Complex is a west-dipping normal fault that does not represent a major tectonic boundary.
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| 14. |
- Behrens, K., et al.
(author)
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Reflection seismic measurements across the Granulite Belt of the POLAR Profile in the northern Baltic Shield, Northern Finland
- 1989
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In: Tectonophysics. - : Elsevier BV. - 0040-1951 .- 1879-3266. ; 162:1-2, s. 101-111
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Journal article (peer-reviewed)abstract
- Reflection seismic measurements were carried out in 1985 on the central part of the POLAR refraction seismic profile in Northern Finland. The survey was planned and executed jointly by the Universities of Helsinki, Uppsala and Hamburg, using digital equipment with a total of 144 channels. By repeating the shots and moving the geophone spreads every day we were able to observe a 42-50 km recording spread. Referred to reflection elements, a line of 84 km total length through the source-receiver midpoints was recorded. We processed the results up to normal moveout-corrected time sections.A number of reflectors dipping 8°-15° to the northeast were recorded in the Lapland Granulite Belt range. These represent a system of sheared granulites which were observed on the surface in the southern part of the profile. From gravity modelling, the bottom of the dipping layers coincides with the lower boundary of the granulites. Between the depths of 22 and 35 km the crust in this area seems to be transparent to seismic signals. This leads to the assumption that the middle part of the crust is characterized by gentle velocity and density gradients. The crust-mantle boundary seems to be a layered Moho with good reflectors lying at depths between 40 and 44 km.
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| 15. |
- Bergman, Björn, et al.
(author)
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High-resolution reflection seismic imaging of the upper crust at Laxemar, southeastern Sweden
- 2002
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 355:1-4, s. 201-213
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Journal article (peer-reviewed)abstract
- A major cost in exploring the upper 1–2 km of crystalline crust with reflection seismics is the drilling required for explosive sources. By reducing the charge size to a minimum, shallow inexpensive shotholes can be drilled with handheld equipment. Here, we present results from a full-scale test using small charges for high-resolution seismic surveying over a nuclear waste disposal study site (not an actual site). Two 2–2.5-km-long crossing profiles were acquired in December 1999 with 10-m shot and geophone spacing in the Laxemar area, near Oskarshamn in southeastern Sweden. After standard processing, including dip moveout (DMO), several subhorizontal to moderately dipping reflections are imaged. Many of the dipping ones can be correlated to fracture zones observed in a ca. 1700-m-deep borehole where the profiles cross and/or to fracture zones mapped on the surface. The imaged fracture zones form a complex 3D pattern illustrating the necessity of having 3D control before interpreting seismic reflection data. Analyses of sonic and density logs from the borehole show that greenstones have significantly higher impedances than the more dominant granite found in the borehole (granite/greenstone reflection coefficient is +0.065). These greenstones may contribute to the reflectivity when associated with fracture zones. In some cases, where they are present as larger subhorizontal lenses, they may be the dominant source of reflectivity. A set of north-dipping (10°) reflectors at 3–3.5-km depth can be correlated to a similar set observed below the island of Ävrö about 3 km to the east.
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| 16. |
- Buchan, K. L., et al.
(author)
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Comparing the drift of Laurentia and baltica in the Proterozoic : the importance of key palaeomagnetic poles
- 2000
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 319:3, s. 167-198
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Journal article (peer-reviewed)abstract
- Key palaeomagnetic poles are defined as those which pass basic reliability criteria and are precisely and accurately dated. They allow a more rigorous analysis of Precambrian continental drift and continental reconstructions than the traditional apparent polar wander path (APWP) approach using mostly non-key poles. Between ca. 2.45 and 2.00 Ga in the early Palaeoproterozoic, key poles define the drift of the Archaean Superior craton of Laurentia, yielding a result that is quite unlike the drift interpreted in earlier studies using the APWP method. There are no early Palaeoproterozoic key poles for the other Archaean cratons that amalgamated to form Laurentia and Baltica prior to 1.8 Ga, so that a rigorous test of early Palaeoproterozoic reconstruction models is not possible. Key poles from Laurentia between ca. 1.46 and 1.267 Ga and Baltica between 1.63 and 1.265 Ga help to define, in a preliminary fashion, the early Mesoproterozoic drift of the two shields. The key pole age match at ca. 1.265 Ga is consistent with Baltica located adjacent to eastern Greenland, and geological considerations suggest that the most reasonable fit aligns the Labradorian belt of Laurentia with the Gothian belt of Baltica. Although there is limited support from non-key poles and key poles that are not matched in age for such a fit as early as ca. 1.8 Ga, no rigorous assessment will be possible until a match in key pole ages is achieved. In the late Mesoproterozoic to Neoproterozoic, Laurentia's drift is reasonably well documented by seven key poles between 1.235 and 0.73 Ga. There are no key poles in this period from Baltica, however, so that a ≈90° clockwise rotation of Baltica relative to Laurentia between 1.265 and 1.0 Ga, widely used in the literature, cannot be confirmed.
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| 17. |
- Chouliaras, Gerassimos, et al.
(author)
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The application of the magnetotelluric impedance tensor to earthquake prediction research in Greece
- 1988
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In: Tectonophysics. - : Elsevier BV. - 0040-1951 .- 1879-3266. ; 152:1-2, s. 119-135
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Journal article (peer-reviewed)abstract
- Continuous short period (0.1-3600 s) measurements of the magnetotelluric field components were conducted simultaneously at two sites in Greece for a period of 5 weeks. The estimation of the impedance tensor elements from 8-hr windows of recorded data, at each station, is found to describe the local electromagnetic induction with great accuracy. The computation of the residual electric field, obtained as the difference between the observed and estimated inductive part of the electric fields, clearly improves the detection of any local electric field anomaly. This method was used in an attempt to detect precursory Sci smic electrical signals (SES) that have been reported to precede earthquakes in Greece. The results indicate the success of this method in resolving ambiguities about the nature of the reported SES, i.e. whether it has an external or internal source. Although during the recording period no large earthquake occurred, five with a magnitude of between ML = 4.0 and ML = 4.3 occurred within a radius of 150 km from one of the stations. The magnetotelluric recordings and the computed residual electric fields for the time intervals reported to contain the SES precursors to these events were analysed in some detail. In two of the cases it was found that the sources could not be related to earthquake processes. In the other three cases the nature of the source of the suspected SES, although electric, could not be established with certainty. These results indicate that for earthquakes of small magnitude (ML ≤ 4.3) or of large epicentral distance (r ≥ 100 km), the detection of a SES is extremely difficult.
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| 18. |
- Elming, Sten-åke, et al.
(author)
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Palaeomagnetism of Proterozoic rocks from the Ukrainian shield : new tectonic reconstructions of the Ukrainian and Fennoscandian shields
- 2001
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 339:1-2, s. 19-38
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Journal article (peer-reviewed)abstract
- A palaeomagnetic study has been performed on Palaeo-Mesoproterozoic rocks from three crustal blocks of the Ukrainian Shield, southern Sarmatia. Primary remanent magnetizations have been isolated in 2.0 Ga monzonite, 2.0-1.8 Ga sandstone, 1.77-1.72 Ga anorthosite and from mafic dykes of probably Palaeo-Mesoproterozoic ages. On basis of these results a sequence of 2.0-1.72 Ga apparent polar wander has for the first time been defined for the Ukrainian Shield. Palaeomagnetic and geological data indicate that there has probably not been any large scale tectonic movements within Sarmatia since the Mesoproterozoic. This suggests that tectonic reconstructions for the Ukrainian Shield may also include Sarmatia. The calculated pole positions for the Ukrainian Shield are significantly different from poles of similar age from the Fennoscandian Shield. The tectonic reconstructions demonstrate that the relative position and orientation of the Ukrainian Shield as a part of Sarmatia in the time interval 2.0-1.78 Ga was different from its present position relative to Fennoscandia. One pole from the Ukrainian Shield falls on the ca. 1.6 or 1.3 Ga part of the Fennoscandian APWP. This pole may represent a time when Fennoscandia was already accreted to Ukrainia. Contemporaneous rifting of the two cratons at ca. 1.35 Ga indicates that they were already joined to each other at that time, which means that the final accretion should have taken place sometimes after ca. 1.8 Ga ago.
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| 19. |
- Elming, Sten-åke, et al.
(author)
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The drift of the Fennoscandian and Ukrainian Shields during the Precambrian : a Palaeomagnetic analysis
- 1993
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In: Tectonophysics. - : Elsevier BV. - 0040-1951 .- 1879-3266. ; 223:3-4, s. 177-198
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Journal article (peer-reviewed)abstract
- A revised Precambrian (2.85-0.6 Ga) Apparent Polar Wander Path (APWP) for the Fennoscandian Shield, based on a new compilation and analysis of data, is presented. In fitting the APW path to successive Grand Mean Palaeomagnetic poles (GMPs), we applied the spherical spline technique originally developed by Jupp and Kent in 1987. The position and orientation of the Fennoscandian Shield during 2.85-0.6 Ga was determined from the GMPs. Major palaeoclimatological findings are used to constrain the palaeomagnetic interpretation of palaeolatitudes. The general drift of Fennoscandia, from relatively high latitudes in the late Archaean-Early Proterozoic to nearly equatorial latitudes in the Middle Proterozoic, correlates with palaeoclimatological indications that a period of cold climate was followed by one of warm climate during this time interval. From the continuous APWP the APW velocities and latitudinal drift velocities of the shield were calculated. An accumulated APW curve was also calculated. The palaeomagnetic data are irregularly distributed and some periods are rather poorly represented. This means that the calculated velocities can sometimes be artifacts of sampling. Late Archaean and Early Proterozoic (2.85-1.90 Ga) data are too sparse to make these calculations meaningful and velocity calculations are therefore restricted to data of 1.90 Ga and younger ages. The accumulated APW curve shows a number of linear segments with varying slopes, indicating sudden changes in drift rate. During the Middle Proterozoic (1.90-1.35 Ga) there was a period when the rate of APW was constant and low and that of latitudinal drift also was low. This pattern changed at ca. 1.35 Ga, and the following Middle-Late Proterozoic period can be described by rapid APW and strongly fluctuating drift velocities. Jotnian rifting and the intrusion of numerous dyke swarms (at ca. 1.25 Ga) correlate with this shift in rate. These changes are attributed to changes in plate configuration. A new database for the Ukrainian Shield is also presented, and GMPs in the 2.32-1.20 Ga range are defined. The database is still inadequate and the comparison of the Ukrainian and Fennoscandian drift histories is therefore tentative. Similarities in position, latitudinal drift and rotation during the Early-Middle Proterozoic are, nevertheless, evident. A close relationship between the shields in this period is consistent with the low APW rate of Fennoscandia, indicating that Fennoscandia may have been part of a larger continent, including the Ukraine, at that time. At ca. 1.2 Ga, the latitudinal position of Ukraine differed significantly from that of Fennoscandia, suggesting that the large shield split up between ca. 1.35 and 1.2 Ga. This would explain the change in APW rate at 1.35 Ga. The subsequent increase in rate was due to a reduction in the size of the shield. The discrepancy in palaeopositions of Fennoscandia and Ukraine at 1.2 Ga led Mikhailova and Kravchenko to suggest a late Precambrian time (1.07-0.57 Ga) for the accreation of Fennoscandia to the East European Platform (EEP). This may be correct as the rate of APW for Fennoscandia decreased in the late Precambrian, reflecting such a consolidation.
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| 20. |
- Holliger, K, et al.
(author)
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Stochastic analysis of sonic logs from the upper crystalline crust: Methodology
- 1996
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In: Tectonophysics. - : Elsevier. - 0040-1951 .- 1879-3266. ; 264:1-4, s. 341-356
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Journal article (peer-reviewed)abstract
- To relate local fluctuations observed in sonic logs to small-scale velocity fabric along boreholes, both filtering effects and noise introduced by the logging procedure must be taken into account. Sonic log velocities are represented as a time series consisting of a large-scale deterministic and a small-scale stochastic component. The deterministic trend, approximated by a low-order polynomial best-fit, contains information on the average velocity structure, whereas the small-scale stochastic variations consist of noise plus in situ velocity variations convolved with the logging system response. The velocity fluctuations of the sonic data considered here are zero-mean and have quasi-Gaussian probability density functions. Therefore, they are well characterised by their second statistical moment, i.e. their autocovariance function. Tests on synthetic data indicate that the autocovariance function corresponding to this data model may be used to extract information on the second-order statistics of the in situ velocity variations along the borehole and to constrain the level of white noise in sonic logs. Ignoring the presence of filtering effects and noise in sonic logs may result in seriously flawed estimates of the second-order statistics of the actual velocity structure. Assuming a von Kármán autocovariance function for the in situ velocity variations, this model provides a good match to the autocovariance functions of sonic log data from the Siljan Ring (Sweden) and Sudbury areas (Canada). Although differing significantly in their noise content, these two data sets yield similar results for the small-scale velocity structure, which is modelled as a bandlimited self-affine time series. For the Siljan Ring borehole we found a close relation between small-scale variations of the borehole diameter as determined from caliper logs and the level of uncorrelated noise present in the sonic log data.
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| 21. |
- Korja, Toivo, et al.
(author)
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The geoelectric model of the POLAR Profile, Northern Finland
- 1989
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In: Tectonophysics. - : Elsevier BV. - 0040-1951 .- 1879-3266. ; 162:1-2, s. 113-133
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Journal article (peer-reviewed)abstract
- Electromagnetic soundings have been made in order to construct a geoelectrical (conductivity) model of the crust along the European Geotraverse (EGT) POLAR Profile. Forty magnetotelluric (MT) soundings, eighteen audiomagnetotelluric (AMT) soundings and ten magnetohydrodynamic (MHD) soundings were made on the main POLAR Profile (POLAR I) and ten more MT soundings on a parallel profile (POLAR II), 40 km to the southeast of the main profile. Analysis of simultaneous recordings by the EISCAT magnetometer chain, and thin-sheet modelling of the effect of the Barents Sea, indicate that neither the source field effects nor the presence of the ocean are significant at periods below 200 s in the measurement area. The magnetotelluric data have been modelled with two-dimensional models representing the regional structure along the profiles. In addition to the regional structure, a thin inhomogeneous surface layer is included in the models in order to explain some local features of the measured response functions. Although details of the surface electrical structures are poorly resolved, the gross features of the geoelectrical cross section are considered to be reliable. The results divide the POLAR Profile into three different blocks. The better conducting Karasjok-Kittilä Greenstone Belt in the south has an average resistivity of less than 10 Ωm. The more resistant Lapland Granulite Belt, with a resistivity between 100 and 200 Ωm, is underlain by conductive (< 5 Ωm), N-dipping layers. The depth for the uppermost conductive layer varies from a few kilometres in the southwestern part of the granulite belt to 13 km in the northeastern part, from where it rises steeply towards the surface close to the boundary between the Lapland Granulite Belt and the Inari Terrain. These features appear to be continuous between the two parallel MT profiles. Within the Inari Terrain a conductive zone at an approximate depth of 10 km and with a resistivity of about 20 Ωm was identified in a resistive upper crust. The geoelectric cross section agrees, in gross detail, with the corresponding gravity, refraction seismic and reflection seismic cross sections of the POLAR Profile. All methods indicated a similar shape for the southwestern part of the Lapland Granulite Belt i.e., granulites have a gently NE-dipping boundary against the underlying Karelian Province. In the northeastern part of the granulite belt the geoelectric model and the gravimetric model show a rather steep S-dipping boundary against the Inari Terrain northeast of the granulite belt.
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| 22. |
- Koyi, Hemin, et al.
(author)
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Salt diapirs of the southwest Nordkapp Basin : analogue modelling
- 1993
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 228:3-4, s. 167-187
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Journal article (peer-reviewed)abstract
- The geometry and evolution of the salt diapirs in the southwestern segment of the Nordkapp Basin (SW NKB) were interpreted on reflection seismic data. Reflection seismic profiles were used to build a dynamically scaled model analogue to study salt tectonics of the basin. The model was prepared using lengths, densities, and sedimentary histories obtained from seismic and well data. Model results suggest that the salt structures in the SW NKB were influenced by basement faults that horizontally stretched and faulted their overburden and induced salt flow by differential loading. Model diapirs rose only where the overburden was faulted. The salt structures are aligned in two NE-SW rows that parallel the major basement faults that outline the basin. Carboniferous salt in the SW NKB formed conformable pillows in the Early Triassic (Scythian), which became diapiric during the late Early and Middle Triassic. The salt diapirs spread to form asymmetric broad overhangs at superficial levels during slow sedimentation in Late Triassic and/or Jurassic. Diapir overhangs were later reactivated because of burial by Cretaceous and Tertiary sediments. Basement faults were mapped by comparing thickness of the sediments and/or level of the reflectors on either side of the diapirs that had relatively narrow overhangs. Depth conversion and restoration of velocity pull-up of reflectors beneath salt diapirs suggest that the salt diapirs of the SW NKB have broad overhangs above narrow stems.
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| 23. |
- Lindqvist, Gustaf
(author)
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Heat flow density measurements in the sediments of three lakes in northern Sweden
- 1984
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In: Tectonophysics. - : Elsevier BV. - 0040-1951 .- 1879-3266. ; 103:1-4, s. 121-140
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Journal article (peer-reviewed)abstract
- Heat flow density measurements in the sediments of three lakes, 36 m, 73 m and 99 m deep, were carried out during a period of 3-5 years. The gradient measurements were made from ice during the winter season with a Bullard-type probe with nine thermistors 0.5 m apart. The thermal conductivity was measured in situ. Corrections were made for the disturbing temperature wave in the horizontally stratified sediments caused by seasonal variations in the bottom water temperature. It is clearly shown that the differences in bottom water temperatures between different years can be fully corrected only by very long time series. The heat flow density values obtained are compared with measurements in boreholes and they seem to be correct to within 20-30%
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| 24. |
- Mulugeta, G., et al.
(author)
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Episodic accretion and strain partitioning in a model sand wedge
- 1992
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In: Tectonophysics. - 0040-1951 .- 1879-3266. ; 202:2-4, s. 319-333
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Journal article (peer-reviewed)abstract
- We model led thrust wedge accretion and deformation partitioning in a passively layered sand, detached and shortened above a smooth rigid decollement. The thrust wedge accretes in piggyback style during forward advance of a rear wall. The passively layered sand accommodates the shortening penetratively, by kinking/ramp folding, and by imbrication. In single layers, the style of compression changes with time and/or stratigraphic position within the sand prism. Initial penetrative layer shortening, above a slipped zone of decollement is succeeded by formation of monoclinal or conjugate shear bands at temporary terminations of decollement. The shear bands subsequently narrow down and lock as thrust ramps. The model sand wedge accrets episodically rather than steadily. Episodicity is controlled by the stick/slip mode of decollement propagation, and by volume loss and compaction of the wedge material in response to convergence. This results in formation of a wedge with a convex-upwards cross-sectional topography
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| 25. |
- Papasikas, N, et al.
(author)
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Interpretation of reflections from the central part of the Siljan Ring impact structure based on results from the Stenberg-1 borehole
- 1997
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In: Tectonophysics. - : Elsevier. - 0040-1951 .- 1879-3266. ; 269:3-4, s. 237-245
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Journal article (other academic/artistic)abstract
- In 1984, 1985 and 1990, several multichannel seismic reflection profiles were shot over the Siljan Ring, a meteorite impact structure believed to have been formed approximately 360 Ma ago. The bedrock of the area consists mainly of gneisses and granites and the ring itself of Palaeozoic sedimentary rocks lying on top granites. Dolerite dikes of different age and orientation have been mapped in the area. The existence of dolerite intrusions at depth has been verified through the drilling of two deep boreholes, Gravberg-1 and Stenberg-1. Interpretation of seismic data and borehole data from the Gravberg-1 borehole showed a strong correlation between high-amplitude subhorizontal reflections and dolerite sills.Geophysical and geological well-logging in the Stenberg-1 borehole showed the occurrence of dolerites in the borehole. Profile 4, running E-W across the borehole, has been reprocessed in order to improve the seismic image. Several thick dolerites below 5.7 km in the borehole correlate with high-amplitude reflectors on the seismic section. Both the logging data and the seismic interpretation suggest that these intrusions are subhorizontal and laterally continuous. Above 5.7 km in the borehole, the dolerites are thinner and are in some cases associated with fracture zones. On the seismic section at these depths there is a complex system of weaker dipping reflectors. Some of these dipping reflectors correlate with either fracture zones, thin dolerites or a combination of both.
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