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The Whitehorse Trough formed during early Mesozoic accretion of the Intermontane terranes to northwestern North America. Here we investigate its thermal history using detrital mineral thermochronology, including 171 single-crystal (U–Th)/He zircon (ZHe) ages from 35 samples, 158 single-crystal (U–Th)/He apatite (AHe) ages from 33 samples, and apatite fission track (AFT) ages from 12 samples. ZHe single crystal ages range from 222 to 42 Ma and define Triassic–Early Jurassic, Late Jurassic, and Cretaceous–Paleogene age groups. AFT central ages range from 95 to 30 Ma with a dominant age peak at ∼50 Ma, and AHe single crystal ages range from 228 to 13 Ma with a dominant age peak between 50 and 40 Ma. Forward and inverse models of thermochronological data are compatible with two regional burial/heating stages that variably reset He in zircon. Maximum temperatures of the Whitehorse Trough strata locally exceeded 150 °C during Early Jurassic burial and shortening into a fold and thrust belt. Following Middle to Late Jurassic exhumation-related cooling and development of a prominent unconformity, Whitehorse Trough strata were buried again. Temperatures locally exceeded 150 °C during the Cretaceous, suggesting maximum burial of between ∼4 and 7.5 km. Heating and cooling rates during the Early–Middle Jurassic were ∼10 °C/myr, coinciding with deposition, fold and thrust belt development, and regional crustal thickening during the final stages of Intermontane terrane accretion. Maximum heating rates during the Cretaceous were ∼4–7 °C/myr and likely correspond to regional crustal thickening of the northern Cordillera hinterland and establishment of an outboard, Andean-type continental arc system. [ABSTRACT FROM AUTHOR]

[1] Fission track analysis was applied to the Precambrian suites of Madagascar in order to identify the lower-temperature cooling histories and their relationships to the Phanerozoic events that affected the island. Apatite ages range from 431 to 68 Ma, and zircon ages range from 452 to 238 Ma. Thermochronologically, the island can be divided into a southern, central, and northern region each with a subdivision on an east-west basis. The southern region is sharply separated from the central region by strongly contrasting apparent apatite ages over the northwest-southeast striking Ranotsara Shear Zone (RSZ). The change in apparent ages over the RSZ is indicative of later reactivation along younger brittle faults. The central region has the oldest ages of the island and has a diffuse contact to the third region northward. Along the entire western margin of the Precambrian basement initial Paleozoic exhumation was followed by heating (burial by sediments) during Jurassic and Cretaceous times. A decrease in ages along the eastern margin from 119 to 68 Ma coincides with the predicted positions of the Marion hot spot after effects of erosion are considered. On the other hand, these ages may represent progressive opening of the margin in a southward direction together with associated denudation of the rift shoulder. The eastern part of the central region has remained very stable since at least Devonian times, undergoing only long-term very slow exhumation at rates of 1-5 m/Myr. INDEX TERMS: 1035 Geochemistry: Geochronology; 1099 Geochemistry: General or miscellaneous; 1206 Geodesy and Gravity: Crustal movements--interplate (8155); 8099 Structural Geology: General or miscellaneous; 8105 Tectonophysics: Continental margins and sedimentary basins (1212); KEYWORDS: thermochronology, passive margins, fission track, Gondwana. Citation: Seward, D., D. Grujic, and G. Schreurs (2004), An insight into the breakup of Gondwana: Identifying events through low-temperature thermochronology from the basement rocks of Madagascar, Tectonics, 23, TC3007, doi:10.1029/2003TC001556.

U-Pb analyses of rutile and titanite commonly yield ages that constrain the timing of cooling rather than the timing of their crystallization. Rutile which grew at or close to peak temperature conditions in a mafic granulite, intermediate granulite and mafic amphibolite within juxtaposed litho/tectonostratigraphic units in the Greater Himalayan Sequence (GHS) of NW Bhutan yield LA-MC-ICP-MS U-Pb lower intercept cooling ages of 10.1 ± 0.4, 10.8 ± 0.1 and 10.0 ± 0.3 Ma, respectively. Numerical finite-difference diffusion models constrained by previously published temperature-time and Pb diffusion data suggest that these ages are best explained by rapid cooling from peak temperature conditions of ∼800 °C at 14 Ma in the granulite-bearing unit and ∼650 °C at 12 Ma in the amphibolite-bearing unit. The good fit between the model and analysed ages confirms the relatively high retention of Pb in rutile suggested by the experimental data. Titanite that grew during an exhumation-related amphibolite facies overprint on an eclogite facies mineral assemblage from the neighbouring Jomolhari Massif yields a U-Pb lower intercept cooling age of 14.6 ± 1.2 Ma. Diffusion modelling suggests that this age is too old to be consistent with the temperature-time paths inferred for the rutile-bearing samples. Instead, the titanite age suggests cooling from ∼650 °C at an earlier time of 17-15 Ma, implying that the high-grade rocks in the Jomolhari Massif experienced a different cooling history from the rest of the GHS in NW Bhutan. Together these data show that high-grade rocks from three apparently different structural levels of the GHS in NW Bhutan experienced rapid cooling at >40 °C Ma−1 at varying times. The highest grade granulite facies rocks were exhumed from deeper structural levels that are not exposed, not preserved, or not yet recognized west of eastern Nepal. A progressive along-strike change in tectonic regime, metamorphic history and/or exhumation mechanism across the orogen is implied by these thermochronologic data. [ABSTRACT FROM AUTHOR]

Introduction: Theory of mind along with alexithymia, represent two important factors involved in an adecvate social functioning of any patients diagnosed with a psychotic disorder, therefore, also in the schizoaffective disorder. Objectives: The purpose of this study is to evaluate the alexithymia and theory of mind in patients diagnosed with schizoaffective disorder, that are in remission and under treatment. Methods: 22 subjects diagnosed with schizoaffective disorder (according to ICD10 criteria) have been included in our study. The subjects have been selected using inclusion and exclusion criteria. The analized parameters were: socio-demographical data, alexithymia (Toronto Alexithymia Scale) and Theory of Mind ("Reading the Mind in the Eyes test"). The data obtained was analyzed statistically. Results: The socio-demographical data revealed that the median age of onset of the disorder was 28,2 years, the median education level was 11,2 years (highschool), the median evolution of the disorder is 10,8 years and all of them are now retired due to sickness or disability. The analyzed data showed that the ability of reading the mind in the eyes in 82% of the patients, as well as the alexithymia (79% of the patients) were impaired. Also, there is a direct correlation between these two; a lower ability to express emotions correlates to a lower ability to identify emotions (r=-0.524324317). Conclusions: In the schizoaffective disorder, theory of mind, as well as alexithymia are impaired and there is a direct correlation between them. [ABSTRACT FROM AUTHOR]