Decoherence of a single-ion qubit immersed in a spin-polarized atomic bath

We report on the immersion of a spin-qubit encoded in a single trapped ion into a spin-polarized neutral atom environment, which possesses both continuous (motional) and discrete (spin) degrees of freedom. The environment offers the possibility of a precise microscopic description, which allows us to understand dynamics and decoherence from first principles. We observe the spin dynamics of the qubit and measure the decoherence times (T1 and T2), which are determined by the spin-exchange interaction as well as by an unexpectedly strong spin-nonconserving coupling mechanism

Miocene gneiss domes in the Pamir: linking graviational collapse of thickened crust to shortening in the Tajik foreland

Abstract HKT-ISTP 2013 A

Clockwise rotation of the Baoshan block due to SSE-ward extrusion of Tibetan crust

Abstract HKT-ISTP 2013 A

The 2008 Nura earthquake sequence at the Pamir-Tian Shan collision zone, southern Kyrgyzstan

We analyzed the 5 October 2008, Mw 6.6 Nura earthquake, which occurred in the border triangle between Kyrgyzstan, Tajikistan, and China, and its aftershock series based on locally recorded seismic data. More than 3000 aftershocks were detected and located, using a double-difference technique and a regional 3-D velocity model. Moment tensors for the main event and the 42 largest aftershocks were determined by full-waveform inversion of long-period displacement seismograms. The Nura main shock was a shallow (∼3.4 km deep) reverse faulting event and occurred on an approximately east striking rupture plane situated east of the Alai Valley, along the Pamir Frontal Thrust of the Trans Alai Range, the leading edge of the Pamir Thrust System. Its presumed rupture plane dips steeply (∼59°) southward. The aftershocks constitute several distinct clusters that can be attributed to the activation of an array of individual faults including the one that was presumably broken by the main shock. Background seismicity occurred mainly further south, behind the crest of the Trans Alai Range, in an approximately east trending zone of dextral transpressional motion in the interior of the Pamir Thrust System. We show that nearly all reactivated structures lie in regions that experienced an increase in Coulomb stress due to the main shock rupture. The Nura earthquake sequence indicates slip partitioning between north-south shortening that creates large earthquakes along the Pamir Frontal Thrust, and lateral movement in the interior of the Pamir Thrust System.This research was funded by DFG bundle TIPAGE (PAK 443), the CAME project bundle TIPTIMON funded by the German Federal Ministry of Education and Research (support code 03G0809), and GFZ. We acknowledge funding for the Earthquake Task Force deployment by GFZ and the Hannover Rück reinsurance company

Crustal flow around the Eastern Himalayan Syntaxis in western Yunnan, China

Abstract HKT-ISTP 2013 A

Geometry and Cenozoic evolution of the Crimean fold-thrust belt from cross-section balancing and kinematic forward modeling

The Crimean fold-thrust belt comprises the onshore Crimean-dome fold-thrust belt and the offshore Sorokin accretionary wedge, a sub-surface imbricate stack with high oil and gas potential. We combine geomorphological and balanced cross-section analyses with published low-temperature thermo¬chronology and offshore seismic data to constrain both its present geometry and Cenozoic structural evolution. We interpret the Crimean dome as a map-scale, ramp-related antiform above the Main Crimean thrust, the basal detachment to the onshore part of the fold-thrust belt. The Main Crimean thrust separates the continental Scythian plate from the transitional to oceanic Eastern Black-Sea basin and likely reactivates an Upper Triassic–Lower Jurassic passive continental margin structure. The Crimean fold-thrust belt has accommodated ~24 km shortening since the Eocene, with ~12 km contraction each in the thick-skinned Crimean dome and the thin-skinned Sorokin accretionary wedge. The intermediate geometries in the kinematic evolution traced by the kinematic forward model are testable by future hydrocarbon exploration and thermochronologic studies.Крымский складчато-надвижные пояс состоит из Крымского куполообразного складчатого пояса и аккреционного клина Сорокина с высокими перспективами на нефть и газ. Объединены геоморфологический анализ и метод балансировки геологических разрезов, опубликованные низкотемпературные термохронологични данные и данные акваториальных сейсмических профилей для воспроизведения как современной строения, так и кайнозойской структурной эволюции. Интерпретировано Крымский купол как антиформну структуру в масштабе карты, связанной с главным крымским надвижкой (базальным детачментом для горной части складчатого пояса). Главный крымский надвижка отделяет континентальную Скифский плиту от переходной океанической Схидночорноморського бассейна и, вероятно, реактивируется структуру пассивной Континенталь окраины верхнего триаса-нижней юры. Крымский складчато-надвижные пояс претерпел ~ 24 км сокращения, начиная с эоцена, с примерно одинаковым сокращением (~ 12 км) в обоих структурах - Крымском куполе и Сорокинском аккреционного клине. Промежуточные стадии деформации, прослежены кинематической форвард-моделью, является предметом проверки будущими поисками углеводородов и термохронологичнимы исследованиями.Кримський складчасто-насувний пояс складається з Кримського куполоподібного складчастого поясу та акреційного клину Сорокина з високими перспективами на нафту і газ. Поєднано геоморфологічний аналіз і метод балансування геологічних розрізів, опубліковані низькотемпературні термохронологічні дані та дані акваторіальних сейсмічних профілей для відтворення як сучасної будови, так і кайнозойської структурної еволюції. Інтерпретовано Кримський купол як антиформну структуру в масштабі карти, що пов’язана з головним кримським насувом (базальним детачментом для гірської частини складчастого поясу). Головний кримський насув відділяє континентальну Скіфську плиту від перехідної океанічної Східночорноморського басейну і, ймовірно, реактивує структуру пасивної континентальої окраїни верхнього тріасу—нижньої юри. Кримський складчасто-насувний пояс зазнав ~24 км скорочення, починаючи з еоцену, з приблизно однаковим скороченням (~12 км) в обох структурах — Кримському куполі та Сорокинському акреційному клині. Проміжні стадії деформації, прослідковані кінематичною форвард-моделлю, є предметом перевірки майбутніми пошуками вуглеводнів і термохронологічними дослідженнями

The crust in the pamir: Insights from receiver functions

The Cenozoic convergence between India and Asia has created Earth's thickest crust in the Pamir‐Tibet Plateau by extreme crustal shortening. Here we study the crustal structure of the Pamir and western Tian Shan, the adjacent margins of the Tajik, Tarim, and Ferghana Basins, and the Hindu Kush, using data collected by temporary seismic experiments. We derive, compare, and combine independent observations from P and S receiver functions. The obtained Moho depth varies from ~40 km below the basins to a double‐normal thickness of 65–75 km underneath the Pamir and Hindu Kush. A Moho doublet—with the deeper interface down to a depth of ~90 km—coincides with the arc of intermediate‐depth seismicity underneath the Pamir, where Asian continental lower crust delaminates and rolls back. The crust beneath most of the Central and South Pamir has a low Vp/Vs ratio (<1.70), suggesting a dominantly felsic composition, probably a result of delamination/foundering of the mafic rocks of the lower crust. Beneath the Cenozoic gneiss domes of the Central and South Pamir, which represent extensional core complexes, the Vp/Vs ratios are moderate to high (~1.75), consistent with the previously observed, midcrustal low‐velocity zones, implying the presence of crustal partial melts. Even higher crustal average Vp/Vs ratios up to 1.90 are found in the sedimentary basins and along the Main Pamir Thrust. The ratios along the latter—the active thrust front of the Pamir—may reflect fluid accumulations within a strongly fractured fault system

Tajik Depression and Greater Pamir Neotectonics From InSAR Rate Maps

Using E-W and vertical deformation-rate maps derived from radar interferometric time-series, we analyze the deformation field of an entire orogenic segment, that is, the Tajik depression and its adjoining mountain belts, Tian Shan, Pamir, and Hindu Kush. The data-base consists of 900+ radar scenes acquired over 2.0–4.5 years and global navigation satellite system measurements. The recent, supra-regional kinematics is visualized in an unprecedented spatio-temporal resolution. We confirm the westward collapse of the Pamir-Plateau crust, inverting the Tajik basin into a fold-thrust belt (FTB) with shortening rates decaying westward from ∼15 to 2 mm/yr. Vertical rates in the Hindu Kush likely record slab-dynamic effects, that is, the progressive break-off of the Hindu Kush slab. At least 10 mm/yr of each, uplift and westward motion occur along the western edge of the Pamir Plateau, outlining the crustal-scale ramp along which the Pamir Plateau overrides the Tajik depression. The latter shows a combination of basin-scale tectonics, halokinesis, and seasonal/weather-driven near-surface effects. Abrupt ∼6 mm/yr horizontal-rate changes occur across the kinematically linked dextral Ilyak strike-slip fault, bounding the Tajik FTB to the north, and the Babatag backthrust, the major thrust of the FTB, located far west in the belt. The sharp rate decay across the Ilyak fault indicates a locking depth of ≤1 km. The Hoja Mumin salt fountain is spreading laterally at ≤350 mm/yr. On the first-order, the modern 20–5 and fossil (since ∼12 Ma) 12–8 mm/yr shortening rates across the FTB correspond

Images of crustal and mantle structure across the northern margin of the Tibet-Pamir plateau

Abstract HKT-ISTP 2013 A