3D numerical modeling of hydrothermal processes during the lifetime of a deep geothermal reservoir

Understanding hydrothermal processes during production is critical to optimal geothermal reservoir management and sustainable utilization. This study addresses the hydrothermal (HT) processes in a geothermal research doublet consisting of the injection well E GrSk3/90 and production well Gt GrSk4/05 at the deep geothermal reservoir of Groß Schönebeck (north of Berlin, Germany) during geothermal power production. The reservoir is located between ?4050 to ?4250 m depth in the Lower Permian of the Northeast German Basin. Operational activities such as hydraulic stimulation, production (T = 150°C; Q = ?75 m³ h^?1; C = 265 g l^?1) and injection (T = 70°C; Q = 75 m³ h^?1; C = 265 g l^?1) change the HT conditions of the geothermal reservoir. The most significant changes affect temperature, mass concentration and pore pressure. These changes influence fluid density and viscosity as well as rock properties such as porosity, permeability, thermal conductivity and heat capacity. In addition, the geometry and hydraulic properties of hydraulically induced fractures vary during the lifetime of the reservoir. A three‐dimensional reservoir model was developed based on a structural geological model to simulate and understand the complex interaction of such processes. This model includes a full HT coupling of various petrophysical parameters. Specifically, temperature‐dependent thermal conductivity and heat capacity as well as the pressure‐, temperature‐ and mass concentration‐dependent fluid density and viscosity are considered. These parameters were determined by laboratory and field experiments. The effective pressure dependence of matrix permeability is less than 2.3% at our reservoir conditions and therefore can be neglected. The results of a three‐dimensional thermohaline finite‐element simulation of the life cycle performance of this geothermal well doublet indicate the beginning of thermal breakthrough after 3.6 years of utilization. This result is crucial for optimizing reservoir management. Geofluids (2010) 10 , 406–421     

THE WUSUN IN NORTHEASTERN CENTRAL ASIA

Among the peoples mentioned in Chinese dynastic chronicles are the Xiongnu and other steppe nomads such as the Yuezhi and the Wusun. The Xiongnu forced both these peoples to abandon their camping grounds and move to Zhetysu. Numerous sites in Tuva of the Late Scythian period (those of the Uyuk–Sagly culture) reveal ties with the Xiongnu and suggest that they were associated with the Wusun. Artifacts from Suglug-Khem-1 and -2 and Khayirakan, Tuva, specifically mirrors with side handles, hairpins, wire earrings, small wooden four-legged tables, painted vessels, etc., are paralleled by finds from burials of the low-ranking Wusun in Zhetysu. Before arriving at Zhetysu, the Wusun crossed the Altai-Sayan highland and the Irtysh below Lake Zaisan, where their presence is attested by sites of the Kula-Zhurga type. The distinctive features of the latter are flexed burials in stone cists and vessels resembling those from Tuva in shape; other artifacts are extremely rare and similar to those from burials of the low-ranking Wusun in Zhetysu.     

PHYSICAL AND CHEMICAL PROPERTIES OF CERAMICS FROM THE CHRONOLOGICALLY TRANSITIONAL (LATE BRONZE – EARLY IRON AGE) SITE OF LINYOVO-1, SOUTHERN SIBERIA: METHODOLOGICAL PROSPECTS AND INTERPRETATION OF THE RESULTS

Linyovo-1, a Late Bronze – Early Iron Age site in southwestern Siberia, is highly important for the study of ceramic production as it offers a rare opportunity for directly examining the clay and paste of which the vessels were made. Technological analysis has allowed us to trace the changes produced by fi ring. For the fi rst time, results of petrographic, X-ray phase, and thermal analysis of vessels are being published. An algorithm of derivatographic measurements and the techniques of data processing and interpretation are outlined in some detail. Prospects for science-based methods of studying pottery are discussed. As an alternative to the traditional approach for assessing fi ring temperature on the basis of thermal analysis, we suggest using a comparative analysis of the preservation of clay components in the ceramic paste to evaluate the quality of fi ring. This approach can be used with regard to vessels from a single site as well as those from different sites and even with regard to various parts of a single vessel.     

MODELS OF MAN'S BIOSOCIAL ADAPTATION IN AN INDUSTRIAL SOCIETY*

The morphological, physiological, and behavioral adaptation of professional athletes can be viewed as a model, being close to the successful hunter's adaptation in a foraging society. Physique, endocrine status, and personality traits were studied in athletes of various professional levels. A set of traits believed to be adaptive for this group is described. Athletes display masculine proportions of head and body, higher testosterone levels, early onset of sexual activity, extroversion, and thoroughness. These fi ndings are discussed from the standpoint of modern ethology and evolutionary anthropology.     

A FOSSIL HUMAN HUMERUS FROM KHVALYNSK: MORPHOLOGY AND TAXONOMY

A fossil humerus from Khoroshevsky Island, Khvalynsk, Saratov Province, previously believed to have been lost eighty years ago, was studied by osteometric, X-ray, tomographic, histological, and paleopathological methods. The results suggest that the fossil represents an adult Neanderthal, apparently male, displaying a peculiar hormonal status which ? nds no direct parallels among known human physiological conditions, either normal or pathological.     

Fruit and seed biomineralization and its effect on preservation

Mineralised fruits and seeds are frequently found in archaeological sediments but their chemical nature has not been often examined. The nature and the origin of these archaeobotanical remains have to be investigated to understand their taphonomic history. Fruits or seeds can be mineralised not only by replacement mineralisation but also by biomineralisation during the plant life. The mineral components of three fossil fruits sampled on the Pleistocene site of Dmanisi were analysed and compared with their modern analogues. Analyses were carried out by means of an environmental scanning electron microscope, equipped with an energy dispersive X-ray device and by means of a Fourier transform infrared spectrometer. Biogenic carbonates and/or biogenic silica were identified in the fossil and modern fruits of some taxa. Comparison between fossil and modern specimens has shown that molecular reorganisation occurred in carbonate and in biogenic silica during fossilisation, through diagenetic processes. The resulting stable mineral structures confer an exceptional preservation to fruits in sediments. Taking into account these taphonomic specificities (transformation and differential preservation), the chronological and palaeoenvironmental aspects of the mineralised fruits are discussed.     

Book Reviews

A Feng 阿风, Ming Qing shidai funü de diwei yu quanli: yi Ming Qing qiyue wenshu, susong dang’an wei zhongxin 明清时代妇女的地位与权利——以明清契 约文书,诉讼档案为中心 (The status and rights of women during Ming and Qing times: focused on contractual documents and litigation archives of the Ming and Qing);Eli Alberts, A History of Daoism and the Yao People of South China;Robert Ford Campany, Making Transcendents: Ascetics and Social Memory in Early Medieval China;Barbara Hendrischke, The Scripture on Great Peace: The “Taiping Jing” and the Beginnings of Daoism (Daoist Classics);Jin Jiang, Women Playing Men: Yue Opera and Social Change in Twentieth-Century Shanghai;Ma Liangkuan 马亮宽, Fu Sinian shehui zhengzhi huodong yu sixiang yanjiu 傅 斯年社会政治活动与思想研究 (A study of Fu Sinian’s thought and social-political work);Daniel J. Meissner, Chinese Capitalists versus the American Flour Industry, 1890–1910: Profit and Patriotism in International Trade;Rong Xinjiang 荣新江, Sui Tang Chang’an: xingbie, jiyi ji qita 隋唐长安: 性别, 记忆及其他 (Sui-Tang Chang’an: gender, memory, and other);Wen-hsin Yeh, Shanghai Splendor: Economic Sentiments and the Making of Modern China, 1843–1949     

CHARACTERIZATION OF CORAL RED SLIPS ON GREEK ATTIC POTTERY*

Samples of red and black gloss from Greek Attic pottery of the late sixth to fifth centuries bc were examined using scanning electron microscopy (SEM and FIB/STEM). The focus of the study was the chemical and microstructural characterization of the red gloss that was first produced during this period. Two groupings of red gloss were revealed. One red was found to be compositionally similar to the black glosses (labelled ‘LCM coral red’). The other red showed more significant chemical differences, such as higher calcium and magnesium, in comparison to the black (labelled ‘HCM coral red’). The existence of two chemically distinct reds—otherwise identical in colour and texture—suggests that there was more than one source of clay available to the Attic potters for producing red.