潍河下游地区浅埋古河道沉积与第四系地层划分

浅埋古河道带以冲洪积扇体为核心向北呈指掌状分布，古河道沉积具有明显的阶段性，早期沉积以中、细砂为主，粒度变化比较大，晚期沉积物以粉砂为主。在垂向上，古河道自下而上分为5段，其粒径呈愈向上愈细的趋势。钻孔剖面分析表明，潍河古河道沉积在横向上摆动幅度不大，沉积物自浅埋古河道主流带向两侧逐渐变细，沉积物粒度也随水动力强弱变化而变化，从上游到下游粒度变细，分选性增强。潍河下游地区晚更新世以来共发育5期古河道，与冰期－间冰期气候变化相对应。其中Ⅰ、Ⅱ期古河道厚度大，颗粒组，纵向上连续性好，为优良的含水层，其埋藏层位与古卤水埋藏层位基本一致，相互贯通，古河道成为卤水入侵的良好通道。晚期古河道沉积厚度大，沉积物粒度小，是早期主要的淡水取水层，但人类开采地下水的活动使其已成为海水入侵的主要通道。     

Period studies of classical Algol-type binaries II: UX Leo,RW Mon,EQ Ori,XZ UMa and AX Vul

This study presents an investigation of the orbital period variations of five Algol type binaries, UX Leo, RW Mon, EQ Ori, XZ UMa and AX Vul based on all available minima times. The O–C diagrams of all systems exhibit a periodic variation superimposed on a downward parabolic segment. The mass loss due to magnetic braking effect in the cooler components is assumed to account for the parabolic variation with a downward shape, while it is suggested that the light-time effect (LITE) due to an unseen component around the eclipsing binaries explains the tilted sinusoidal changes in their O–C diagrams. The orbital period decrease rates for the systems are estimated as approximately between about 0.7 and 2.5 s per century. It is clearly seen that mass loss effect is more dominant than the expected mass transfer for classical Algols in this study. The minimum mass of the probable third bodies around the eclipsing pairs was calculated to be ?0.5 M_⊙ except for UX Leo, in which it was estimated to be approximately 0.9 M_⊙. In order to search for third lights in the light curves of five systems, the V-light curves of the systems were analyzed and their physical and photometric parameters were determined. For UX Leo, a significant third light contribution was determined. We found a very small third light that can be tested using multi-color light curves, for RW Mon, EQ Ori and XZ UMa, while a third light for AX Vul could not be exposed.     

The Manyas fault zone (southern Marmara region,NW Turkey): active tectonics and paleoseismology

The Manyas fault zone (MFZ) is a splay fault of the Yenice Gönen Fault, which is located on the southern branch of the North Anatolian Fault System. The MFZ is a 38 km long, WNW–ESE-trending and normal fault zone comprised of three en-echelon segments. On 6 October 1964, an earthquake (Ms = 6.9) occurred on the Salur segment. In this study, paleoseismic trench studies were performed along the Salur segment. Based on these paleoseismic trench studies, at least three earthquakes resulting in a surface rupture within the last 4000 years, including the 1964 earthquake have been identified and dated. The penultimate event can be correlated with the AD 1323 earthquake. There is no archaeological and/or historical record that can be associated with the oldest earthquake dated between BP 3800 ± 600 and BP 2300 ± 200 years. Additionally, the trench study performed to the north of the Salur segment demonstrates paleoliquefaction structures crossing each other. The surface deformation that occurred during the 1964 earthquake is determined primarily to be the consequence of liquefaction. According to the fault plane slip data, the MFZ is a purely normal fault demonstrating a listric geometry with a dip of 64°–74° to the NNE.     

Second order rotational effect on the oscillation frequencies of V1162 Ori

V1162 is a δ-Scuti type variable star for which a rotational velocity of V  sini=46±4 km s⁻¹ has been observed. The star has been modelled according to its observed parameters and oscillation frequencies. The results obtained by approximating rotation to the first order have been compared with the ones provided by new calculations that include rotation up to the second order. We found that second order rotation term should be included in frequency calculations for comparatively high rotation speeds.     

Period variation and the new light curves of V471 Tauri

The light curve and period variation of the eclipsing system V471 Tau is discussed. The migration period of 191 days obtained recently by Ibanolu agrees well with the new observations. The period decreases by about one second per century, which may correspond to a mass transfer of 1×10^–7 solar mass. Furthermore, the O–C diagram shows a noticeable sine curve super-imposed on the parabolic variation. The period of the sine curve is about 3.1 years.     

Comment on “Comparison of the Ability of ARIMA,WNN and SVM Models for Drought Forecasting in the Sanjiang Plain,China” by Yuhu Zhang,Huirong Yang,Hengjian Cui,and Qiuhua Chen,in Natural Resources Research DOI: 10.1007/s11053-019-09512-6

Natural Resources Research - We thank Zhang et al. (Nat Resour Res, 2019. https://doi.org/10.1007/s11053-019-09512-6) for investigating the accuracy of artificial intelligence techniques in the...     

Grain size and heavy mineral distribution as related to hinterland and environmental conditions for modern beach sediments from the Gulfs of Antalya and Finike, eastern Mediterranean

Backshore sediment samples from 22 beaches along the Antalya and Finike Gulfs have been studied for their grain size, chemical and heavy mineral composition. Data presented here suggest that well- to moderately-sorted (0.41 Φ–0.92 Φ) medium sand (1 Φ–2 Φ) represents dominant mean grain size in most beaches. In contrast, some beaches from the western part of the Gulf of Antalya (Göynük, Kemer-Kiriş and Beldibi) are composed of pebble- to boulder-size grained beaches which are located close to mouths of short and steep-gradient ephemeral rivers entering the sea from the Western Taurus Mountains. The heavy mineral assemblages are dominated by detrital opaque minerals (14–58% magnetite, chromite, and hematite), pyroxene (8–65% augite), amphibole (3–15% tremolite and actinolite), epidote (3–25%), garnet (2–9% pyrope and almandine) and micas (3–20 biotite, muscovite and chlorite). The very high concentrations of heavy minerals (up to 86% of bulk sediment) together with the significant concentrations of some elements found in beach sediments from the Gulf of Finike and western Gulf of Antalya (Fe: 18.40%; Cr: 10.00%; and Ti: 1.32%) are indicative of ultramafic origin, mainly derived from the ophiolitic rocks of the Antalya–Tekirova nappe on coastal hinterland.     

Ultraviolet studies of the interstellar gas in the direction of the stars AE Aur (09.5V) andθ 2 Ori A (09.0V)

We have studied high-resolution SWP spectra of AE Aur and ² Ori A, obtained from the International Ultraviolet Explorer Satellite; and derived curve of growth and column densities ofCii,Cii ^*, Alii, Siii, Siii ^*,Sii, Crii, Feii, Niii, and Znii. It has been possible to fit these ions on one empirical curve of growth with a velocity parameterb=13 km s^–1 for both stars.Based on the observations made by the International Ultraviolet Explorer (IUE), and collected at the Villafranca Satellite Tracking Station of the European Space Agency.     

Seismological investigations of fireworks factory explosions in Hendek-Sakarya (Turkey)

Journal of Seismology - On July 3, 2020, a sequence of explosions occurred in the Hendek fireworks factory in Sakarya, Turkey. The explosion caused great material damage and loss of life. In this...