LITHOSPHERE 2021: ELEVENTH SYMPOSIUM ON STRUCTURE, COMPOSITION AND EVOLUTION OF THE LITHOSPHERE: PROGRAMME AND EXTENDED ABSTRACTS

The Central Svecofennian Arc Complex (CSAC) and the Southern Svecofennian Arc Complex (SSAC) showdifferent ages of peak metamorphism: ~1.88 Ga in the CSAC and ~1.83 Ga in the SSAC. In the present project we study the age of the metamorphism in SW Finland. We have collected two samples. Of these the Eurajoki leucosome zircons were > 1.92 Ga, i.e.,inherited, but monazites show two populations: ~1.83 Ga and ~1.7 Ga. The zircons from the Rauma leucosome yielded two populations: ~1.86 Ga and ~1.83 Ga. The monazites show ages of ~1.83 Ga and ~1.7 Ga. We interpret that the ~1.86 Ga zircons represent the older metamorphism and the 1.83 Ga zircon and monazite group to represent the younger metamorphism. The 1.7 Ga group is unusual and needs further investigation.</p

Promoting Client Participation and Constructing Decisions in Mental Health Rehabilitation Meetings

The chapter analyzes practices by which support workers promote client participation in mental health rehabilitation meetings at the Clubhouse. While promoting client participation, the support workers also need to ascertain that at least some decisions get constructed during the meetings. This combination of goals—promoting participation and constructing decisions—leads to a series of dilemmatic practices, the dynamics of which the chapter focuses on analyzing. The support workers may treat clients’ turns retrospectively as proposals, even if the status of these turns as such is ambiguous. In the face of a lack of recipient uptake, the support workers may remind the clients about their epistemic access to the content of the proposal or pursue their agreement or commitment to the idea. These practices involve the support workers carrying primary responsibility over the unfolding of interaction, which is argued to compromise the jointness of the decision-making outcome.The chapter analyzes practices by which support workers promote client participation in mental health rehabilitation meetings at the Clubhouse. While promoting client participation, the support workers also need to ascertain that at least some decisions get constructed during the meetings. This combination of goals—promoting participation and constructing decisions—leads to a series of dilemmatic practices, the dynamics of which the chapter focuses on analyzing. The support workers may treat clients’ turns retrospectively as proposals, even if the status of these turns as such is ambiguous. In the face of a lack of recipient uptake, the support workers may remind the clients about their epistemic access to the content of the proposal or pursue their agreement or commitment to the idea. These practices involve the support workers carrying primary responsibility over the unfolding of interaction, which is argued to compromise the jointness of the decision-making outcome.Peer reviewe

Social navigation

In this chapter we present one of the pioneer approaches in supporting users in navigating the complex information spaces, social navigation support. Social navigation support is inspired by natural tendencies of individuals to follow traces of each other in exploring the world, especially when dealing with uncertainties. In this chapter, we cover details on various approaches in implementing social navigation support in the information space as we also connect the concept to supporting theories. The first part of this chapter reviews related theories and introduces the design space of social navigation support through a series of example applications. The second part of the chapter discusses the common challenges in design and implementation of social navigation support, demonstrates how these challenges have been addressed, and reviews more recent direction of social navigation support. Furthermore, as social navigation support has been an inspirational approach to various other social information access approaches we discuss how social navigation support can be integrated with those approaches. We conclude with a review of evaluation methods for social navigation support and remarks about its current state

Timing of syn-orogenic, high-grade transtensional shear zone formation in the West Uusimaa Complex, Finland

We present zircon and titanite U-Pb ages from granulite-facies transtensional shear zones and a greenschist facies strike-slip shear zone in the Karkkila-Vihti area, West Uusimaa. The zircon rim and titanite ages of c. 1815−1820 Ma from the transtensional shear zones constrain the evolution of the orogenic deformation from compression-dominated to syn-compressional lateral-escape within this part of the Fennoscandian shield while the zircon rim and titanite ages of 1790−1800 Ma give the timing of the late- to post-orogenic low-grade reactivation of the large-scale Somero-Karkkila fault zone. The new age data further constrain the timing of the changes in the crustal deformation style during orogenesis from i) compression-dominated to combined transpression - lateral stretching and escape, to ii) the late- to post-orogenic transition into retrograde conditions

The Veikkola granite area in southern Finland: Emplacement of a 1.83-1.82 Ga plutonic sequence in an extensional regime

Four granite intrusions and coeval small enderbite intrusions, belonging to the lateorogenic (1850–1820 Ma) magmatism of the Svecofennian orogeny, are described in the Veikkola area of southern Finland. The granites are leucocratic, heterogeneous and characterized by abundant garnet. The oldest granite is layered whereas the younger ones are more homogeneous. Geochemically the granites are peraluminous and have high contents of SiO2 (71–76 wt.%). Their major and minor element composition varies significantly but the REE patterns are fairly similar. Garnet mainly crystallized from melt but some garnet in the granites may be restitic. Garnet composition is relatively constant implying slow equilibration with the melt. In addition to garnet-bearing felsic layers in the oldest granite, the granites are crosscut by garnet-bearing dikes and veins. The layers, dikes and veins are higher in REE and Fe/Mg than the host granites and are considered partial melts from the granites. The abundant garnet in the felsic layers, dikes and veins crystallized from melt. Thermobarometry calculations indicate 3.5–5 kbar and ~650–700°C estimates for crystallization of the felsic layers in the oldest granite whereas the host granite yields ~1.5 kbar higher pressure. The granites were probably derived by dehydration melting of layered, metagreywacke-dominated rocks. Melting was fluid-absent both during generation of the granites and during formation of the felsic layers, dikes and veins. The oldest granite (1850 Ma) was emplaced at mid-crustal depth before extensional deformation. Layering in the oldest granite is regarded as the result of deformation-induced remelting of the host granite at a higher crustal level, during protracted extension and progressive regional metamorphism. The other three granites and the enderbite were emplaced at a late stage of extension, at or close to the peak of metamorphism (1.83–1.82 Ga)

How does orogenic crust deform? Evidence of crustal-scale competent behaviour within the partially molten middle crust during orogenic compression

Granitic partial melts are generally thought to significantly weaken the orogenic crust and, ultimately, lead to the collapse of an orogen. Studies from different orogens have shown that the syn-melt deformation behaviour at the orogenic scale is, however, more complex. In addition, once fully crystalline, granitic material strengthens the crust. Linking the evolution from melt-present to melt-absent deformation at the scale of the orogen is a challenging but necessary task if one wishes to investigate the overall behaviour of the middle crust. In this paper, we make observations of orogen-scale deformation, developed over a period of 30–40 Ma during crustal partial melting of the middle and lower crust of a Palaeoproterozoic orogen. The crust shows a globally common pattern where coeval partial melting, compressional deformation, and transtensional structures co-exist. We demonstrate this complex interaction through an integrated approach using multiple datasets. The key observation is that of widespread, regular, orogen-scale shortening by folding of sub-horizontal anatectic granitic sheets and highly migmatized lithologies; this shortening interacted with modest orogen-parallel lateral stretch expressed as local extensional/transtensional structures. The pervasive and dominant deformation style is that of folding of the syn-kinematic granite sheets and voluminous migmatites: this demonstrates that the principal deformation style of deformation within the partially molten mid-crust is competent rather than weak. The observed evidence of weak behaviour such as strike-slip or transtensional shear zones accommodating lateral escape are localized in comparison and not necessarily associated directly with the granite sheets or the highly migmatized volumes of the crust. Moreover, the strain intensity (fold wavelengths and amplitudes) seems independent of the overall melt fraction. The implications are that, while widespread volumes of partial melt will weaken the crust overall (compared to the brittle upper crust) and while individual melt bodies can possibly persist for up to some millions of years in the middle crust, i) the relative strength between (partially) molten volumes is not primarily controlled by melt fraction; and ii) individual melt volumes may be too short-lived at the time-scale of orogenic deformation (i.e. orogenic strain rates) to significantly influence the overall deformation style

The age and origin of the Vaasa migmatite complex revisited

The origin of the Vaasa migmatite complex was studied by using whole-rock Sm-Nd and zircon Lu-Hf and U-Pb data in conjunction with whole-rock major and trace element geochemistry. The concordia ages of five Vaasa area granitoid samples are 1.88–1.86 Ga, constraining the age of peak migmatization. The ages of inherited zircon cores in the samples show two clear age populations at 2.02–1.92 Ga and c. 2.7 Ga, which correspond to ages yielded by a mica schist sample from the adjacent Evijärvi belt, as well as with published values for the Evijärvi belt zircon. The initial εNd values of the Vaasa complex samples are relatively unradiogenic (from -3.0 to -2.0). Such values are comparable to a value (-3.6) calculated for the Evijärvi mica schist, as well as to literature values (from - 3.0 to -0.5) for the Evijärvi belt. The average initial zircon εHf values of four of the granitoids range from -10 to -5 and are in agreement with the Nd-isotopic results, whereas the northmost sample has a significantly higher value (+1). The deviation is suggested to result from disequilibrium melting of zircon. The isotopic and geochronological data indicate that the Vaasa complex granitoids formed by partial melting of the Evijärvi belt metasedimentary rocks

U-Pb ages and Nd isotope characteristics of the lateorogenic, migmatizing microcline granites in southwestern Finland

U-Pb ages and whole-rock Nd isotope data have been obtained from the Paleoproterozoic lateorogenic migmatizing microcline granites of southwestern Finland. Isotope dilution and ion microprobe U-Pb data on zircons and monazites show that the age spectrum of these granites is at least 1.85-1.82 Ga. Commonly, zircons and monazites record the same ages. The age variation in the Veikkola granite area is of the order of 25 Ma and indicates that this seemingly homogeneous granite consists of two separate intrusions. The zircons of the lateorogenic granites are pervasively altered and conventional U-Pb results are commonly discordant. The ion microprobe studies reveal that the granites contain very few inherited zircons with preserved original U-Pb isotope ratios, with the exception of the Oripää granite. Initial εNd values, mostly in the range of -0.5 to -1.0, imply a moderate input of older crustal material into most of the lateorogenic granites. A shift from more juvenile to less radiogenic Nd isotope composition is observed from north to south, and the variation pattern of εNd values of the lateorogenic granites is thus similar to that of the surrounding synorogenic granitoid rocks

Laughter as medical providers' resource : negotiating informed choice in prenatal genetic counseling

This article aims to challenge the perception that in medical encounters laughter is an interactional resource primarily employed by patients. Drawing on 34 video-recorded prenatal genetic counseling (PGC) sessions collected in a Hong Kong hospital, and combining quantitative and qualitative methods, we illustrate that laughter is in fact frequently employed by the medical providers in our data. The particular focus of the article is on the ways in which laughter initiated by the medical providers assists interlocutors in negotiating informed choice, a crucial aspect of PGC sessions. Findings indicate that laughter initiated by the medical providers performs at least two PGC-specific functions: It assists the medical providers in olaughing offo and overcoming patients' resistance, and it helps them in dealing with patients' direct questions. Laughter is thus an important resource for the medical providers in pursuing the institutional goals of the interaction, namely negotiating informed choice with their patients