Supplemental Material: Bulldoze and rebuild: Modifying cratonic lithosphere via removal and replacement induced by continental subduction

 Analytical methods and results, supplemental figures (S1–S9), and tables (S1–S6). </p

A Phase Correction Model for Fourier Transform Spectroscopy

In Fourier transform spectroscopy (FTS), the conventional Mertz method is commonly used to correct phase errors of recovered spectra, but it performs poorly in correcting nonlinear phase errors. This paper proposes a phase correlation method–all-pass filter (PCM-APF) model to correct phase errors. In this model, the proposed improved phase correlation method can correct linear phase errors, and all-pass filters are applied to correct the residual nonlinear phase errors. The optimization algorithm for the digital all-pass filters employs an improved algorithm which combines the subtraction-average-based optimizer (SABO) and the golden sine algorithm (Gold-SA). The proposed PCM-APF model demonstrates high correction precision, and the optimization algorithm for the filters converges faster than traditional intelligent optimization algorithms

Design of Compact Mid-Infrared Cooled Echelle Spectrometer Based on Toroidal Uniform-Line-Spaced (TULS) Grating

A traditional flat-panel spectrometer does not allow high-resolution observation and miniaturization simultaneously. In this study, a compact, high-resolution cross-dispersion spectrometer was designed based on the theoretical basis of echelle grating for recording an infrared spectrum. To meet the high-resolution observation and miniaturization design requirements, a reflective immersion grating was used as the primary spectroscopic device. To compress the beam aperture of the imaging system, the order-separation device of the spectrometer adopted toroidal uniform line grating, which had both imaging and dispersion functions in the spectrometer. The aberration balance condition of the toroidal uniform line grating was analyzed based on the optical path difference function of the concave grating, and dispersion characteristics of the immersed grating and thermal design of the infrared lens were discussed based on the echelle grating. An immersion echelle spectrometer optical system consisting of a culmination system, an immersed echelle grating, and a converged system was used. The spectrometer was based on the asymmetrical Czerny-Turner and Littrow mount designs, and it was equipped with a 320 &times; 256 pixel detector array. The designed wavelength range was 3.7&ndash;4.8 &mu;m, the F-number was 4, and the central wavelength resolution was approximately 30,000. An infrared cooling detector was used. The design results showed that, in the operating band range, the root implied that the square diameter of the spectrometer spot diagram was less than 30 &mu;m, the energy was concentrated in a pixel size range, and the spectrometer system design met the requirements

Bulldoze and rebuild: Modifying cratonic lithosphere via removal and replacement induced by continental subduction

Establishing the mechanisms for craton modification is critical for understanding cratonic stability and architecture. Both plate tectonics and mantle plumes can cause weakening, mechanical decoupling, and even lithospheric removal. But craton modification  – craton destruction accompanied or followed by craton rejuvenation  – has received less attention. It is well-known that oceanic subduction dominantly destroys cratonic lithosphere with replacement to a lesser degree, and mantle plumes have been related to both destruction and rejuvenation. The role of continental subduction in craton modification, however, remains a comparatively open question. The North China Craton, as a previously stable continent with a lithosphere of more than 200 km since the Paleoproterozoic, was reworked and substantially destroyed since the Mesozoic, with intensive destruction occurring in the Early Cretaceous. Earlier in the Mesozoic, North China Craton experienced a continent-continent collision (as the upper plate) with the South China Block, forming the Sulu orogenic belt, providing an opportunity to understand the potential for craton modification due to deep continental subduction In the North China craton, we report the presence of material (i.e., Yunshan unit) sourced from the underlying subducted plate. It is composed of foliated monzonitic granite and metamorphic sedimentary rocks that locally experienced crustal anatexis. Through detailed zircon U-Pb dating, it formed at latest Triassic (ca. 212 Ma). Importantly, the 800–700 Ma inherited zircons from the Yunshan foliated granite resemble those from the South China Block rather than the North China Craton. According to structural and magnetic data, the fabrics of the Yunshan foliated granite, characterized by gentle magnetic/mesoscopic foliations and conspicuous NW-SE-trending magnetic/mesoscopic lineations with a top-to-the-NW shearing. Its geometry, kinematics, and timing all compare favorably with the latest Triassic extensional structure accounting for the exhumation of the Sulu orogenic belt. We thus interpret the Yunshan unit to have been sourced from the subducted South China Block, then exhumed and emplaced into the overriding North China Craton (Fig. 1A). Combining our new results with previous geological and geophysical data, we argue that from 250–220 Ma a 200-km-long tract of North China Craton lithosphere was bulldozed by the subducted South China Block, resulting in a lithospheric suture far from the suture zone at the surface. This lithospheric removal occurred at mid-lower crustal levels (16–20 km depth)  – much shallower than previously thought possible. The bulldozed North China Craton lithosphere was simultaneously replaced by the reworked underlying South China Block plate. Such a “bulldoze and rebuild” lithospheric modification process minimized asthenosphere-lithosphere interaction, thus preventing the North China Craton from further modification (Fig. 1B–1D). Because there was essentially no net loss of lithosphere during deep continental subduction, the North China Craton largely maintained its stability for the time and did not suffer intensive destruction until later Early Cretaceous palaeo-Pacific oceanic subduction. This “bulldoze and rebuild” model can thus account for how a craton can maintain its stability during a collision with another continental plate

Triassic−Jurassic evolution of the eastern North China Craton: Insights from the Lushun-Dalian area, South Liaodong Peninsula, NE China

International audienceThe Lushun-Dalian area of the South Liaodong Peninsula, in NE China, located in the SE margin of the North China Craton (NCC) exposes a suite of Middle-Late Proterozoic low-grade metamorphic sedimentary rocks which can be divided into a lower competent layer, a middle incompetent layer, and an upper competent layer on the basis of lithology and deformation style. Two stages of deformation recorded both in the metasedimentary rocks and a magmatic complex intruded in them indicate that the Lushun-Dalian area is a key region to decipher the Triassic−Jurassic tectonic evolution of the eastern NCC. The earliest D1 deformation mylonitized the magmatic complex and thrusted it northeastward over the low-grade metasedimentary rocks, in which a series of NE-verging folds and NE-directed brittle thrust faults developed. The D2 deformation erased the D1 fabrics in the incompetent layer by a top-to-the-NW ductile shearing and refolded the D1 fabrics in the lower and upper competent units, producing a series of km-scale SW-plunging folds. New zircon secondary ion mass spectrometry and laser ablation−inductively coupled plasma−mass spectrometry U-Pb ages from the magmatic complex and the granite porphyry dikes intruded in it, combined with the unconformity between the low-grade metasedimentary rocks and the Early Cretaceous volcanic rocks, indicate that D1 and D2 occurred after 211 Ma and before the Early Cretaceous. The decrease of the deformation intensity of D1 and D2 from the Lushun-Dalian area toward the interior of the NCC in the NE and NW directions suggests that D1 was the structural response in the overriding plate to the NCC-South China Block convergence during the Late Triassic to Early Jurassic, and D2 was the structural response to the northwestward subduction of the Paleo−Pacific plate beneath the NCC in the Middle-Late Jurassic. The superimposition of D2 on D1 recorded a significant tectonic transformation from the nearly E-W−trending Tethysian domain to the NE-SW−trending Pacific domain

Stray Light Analysis and Suppression for an Infrared Fourier Imaging Spectrometer

To improve the accuracy of infrared radiation characteristics measurement in the aviation field, an infrared Fourier transform imaging spectrometer based on a double-swing solid angle reflector was designed. This imaging spectrometer operates in the 3–5 μm wavelength range and has a field of view of 1.7° × 1.7°. This article presents a comprehensive analysis of the system’s stray light and also studies the impact of external stray light on the imaging quality, along with the influence of internal stray light on the interference effects and the spectral resolution. It also present the design of a hood that suppresses the point source transmittance of the external stray light down to the order of 10−4. Based on this, we propose a method that incorporates the introduction of wedge and inclination angles. Additionally, a numerical range is provided for the addition of these angles on the beam splitter mirror and compensation plate. This ensures the effective suppression of any internal stray light. This study fills the gap in the knowledge about Fourier transform imaging spectrometers operating in the mid-infrared band for aviation applications, and proposes a suppression method suitable for interference systems, which is also suitable for Fourier transform imaging spectrometers based on other types of interferometers. This study broadens the application field of Fourier transform imaging spectrometers in stray light, and has great significance to promote the development of Fourier transform imaging spectrometer

Distinctive roles of L-type calcium channels subtypes within the dorsal hippocampus in formation of morphine withdrawal-induced aversion in rats

Although the negative effects coming along with opiate withdrawal are in part modulated by L-type calcium channels (LTCCs), the distinctive physiological properties and functions of LTCCs subtypes suggest differential roles of subtypes during withdrawal. The present study aimed to examine the contributions of LTCC subtypes, Cav1.2 and Cav1.3, within the dorsal hippocampus (DH) in naloxone-precipitated morphine withdrawal using the conditioned place aversion (CPA) paradigm. Firstly, we injected the non-specific LTCCs antagonist verapamil into the DH of morphine-dependent rats before conditioning an environment with naloxone-precipitated withdrawal. Our results showed that verapamil blocked the acquisition of CPA. Then, to explore the molecular mechanisms of LTCCs subtypes during withdrawal, we measured the protein expression of Cav1.2 and Cav1.3 in morphine-dependent rats under different conditions. In morphine-dependent rats, conditioning with withdrawal increased Cav1.2 expression in the membrane, while only acute naloxone injection increased the membrane expression of Cav1.3. To further determine the causal roles of LTCCs subtypes in the withdrawal process, we used Cav1.2 siRNA or Cav1.3 shRNA to knock down the expression of subtypes and detected the effects on CPA and somatic withdrawal signs in morphine-dependent rats. Cav1.2 siRNA, but not Cav1.3 shRNA, inhibited the acquirement of CPA and relieved somatic withdrawal symptoms. Together, our findings reveal that Cav1.2, but not Cav1.3 plays an important role in mediating morphine withdrawal, suggesting this subtype may serve as a potential therapeutic target for the treatment of negative effects in opiate dependence