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1.
An archaeological geophysics investigation was conducted at the site of the Wright Brothers' 1910 hangar near Dayton, Ohio. The hangar was destroyed as part of base renovation during the buildup to World War II, and its exact location is unknown. The purpose of the investigation is to confirm the exact location of the hangar and to locate any buried artifacts from the Wright Brothers occupation of the site. Ground penetrating radar (GPR), electromagnetic, and magnetic surveys were conducted over a 68 × 100 m area, approximately centered on the suspected location of the hangar. Localized anomalies as well as areal anomalies are identified in the geophysical data. Rectangular anomalous areas are identified that are generally consistent with the suspected location of the hangar. A 1924 aerial photograph showing the hangar was digitally scanned and georeferenced to the site survey area. Two of the rectangular geophysical anomalous areas are consistent with the hangar location from the aerial photograph location. A third rectangular area, defined from GPR survey data, is immediately adjacent to the aerial photograph location. It is postulated that base engineers may have bulldozed the hangar debris onto an area adjacent to its original location and either burned it there or buried it in a trench. A prioritized exploratory program is proposed for investigating the sources of the geophysical anomalies. © 1994 John Wiley & Sons, Inc. 相似文献
2.
《China Geology》2019,2(1):40-48
Engineering construction actively occurs in coastal zones, and these areas have numerous potential geological hazard factors. Since 2009, the development of geological surveys in sea areas has promoted extensive geophysical surveys in Qingdao offshore. In the present study, the types and distribution of potential geological hazard factors were systematically revealed using sub-bottom profile data, side-scan sonar data, and single-channel seismic data, among others. Based on previous research findings, the potential geological hazard factors are classified, and control factors in Qingdao offshore are discussed. The research results show that the primary potential geological hazards include active faults, buried paleo channels, shallow gas, irregular bedrock, eroded gullies, estuary deltas, tidal sand ridges, and seawater intrusion. In addition, neotectonic movement, sea level changes and sedimentary dynamic processes were the main factors that affected the distribution of geological hazards in Qingdao offshore.©2019 China Geology Editorial Office. 相似文献
3.
Geophysical and hydrological investigations at the west bank of Nile River (Luxor, Egypt) 总被引：6，自引：5，他引：1
M. Elwaseif A. Ismail M. Abdalla M. Abdel-Rahman M. A. Hafez 《Environmental Earth Sciences》2012,67(3):911-921
Luxor, the modern Egyptian city that occupies the site of ancient Thebes, is famed for its magnificent ancient monuments. Since 1967, the Aswan high dam has prevented the annual flooding of the Nile River, resulting in excessive salt accumulation on the Nile floodplains and on exposed monument surfaces. In addition, the expansion of agricultural land within the Luxor study area has resulted in increased salinity and groundwater level. These conditions accelerate the degradation of buried and exposed monuments that were fairly well preserved in the past. To mitigate this problem, it is necessary to first understand the near-surface setting and the groundwater conditions of the Luxor area. A geophysical investigation was carried out using resistivity and electromagnetic surveys. In addition, a chemical analysis was conducted of some surface water samples collected from canals and the sacred lake of Memnon Temple. Based on the results of the geophysical surveys and the chemical analysis of the water samples, the shallow subsurface was characterized into four geoelecterical units. Groundwater flow directions were determined to be from the central area to the west, causing a rise in the groundwater levels and groundwater salinity in the area of monuments. 相似文献
4.
Environmental settings on the Ionian coastal plain and inner shelf seaward of Locri‐Epizephiri in Calabria, Italy, differed markedly before, during, and following settlement by the Greeks. Sediment core analyses and geophysical surveys in this study support recent archaeological findings and the hypothesis that the margin may once have served as a harbor and/or shipyard. The subsurface Holocene stratigraphy records that (1) the shoreline advanced to a maximum landward position before Greek settlement, then regressed offshore to what is now the inner shelf before once again migrating landward. These marked coastal shifts were triggered primarily by land uplift and probable subsidence offshore along this structurally active Calabrian Arc segment. Associated with this are: (2) a sediment fining‐upward sequence in Greek–Roman time that indicates only partial protection of the coastal area, and (3) possible presence of subsurface structures seaward of the city wall in a sector now positioned ∼200 m offshore. © 2010 Wiley Periodicals, Inc. 相似文献
5.
6.
Delineation of mafic intrusions near Bedford (Virginia,USA) using geological and geophysical methods
In the present work, geological and geophysical methods were used to delineate the locations of multiple mafic intrusions
at the Claytor Nature Study Center (CNSC) near Bedford, VA. An investigation of the groundwater hydrology of CNSC was launched
in 2007. As a first step in that project a preliminary geological survey revealed sparse evidence of a number of diabase intrusions
in the area. While diabase intrusions are not particularly permeable features, contact metamorphism of the host rock could
provide conduits for groundwater due to stress fractures and joints and high-temperature recrystallization of the rock matrix.
Following the geological survey, geophysical surveys including seismic refraction, ground penetrating radar, and magnetic
ground measurements were conducted to determine the location and extent of these multiple igneous intrusions. Seismic and
radar surveys proved to be inconclusive, but the magnetic surveys showed strong magnetic anomalies. The magnetic data were
obtained using a Geometrics G-856 proton precession magnetometer and were interpreted using the Mag2dc algorithm and SGeMS
geostatistical software. The results show that the intrusions are dikes that cut across nearly perpendicular to the regional
metamorphic structures and trend generally north–south with a dip of approximately 75°–90° to the west. These findings are
consistent with one of the general directions of stresses associated with the North Atlantic seafloor spreading in late Triassic
or early Jurassic period. Subsequent hydrologic testing and groundwater modeling confirm the role of the dikes in the overall
hydrogeology of the site. 相似文献
7.
Gravity, magnetic, and seismic surveys were conducted across the Wasatch fault zone east of Springville, Utah, near the mouth of Hobble Creek Canyon. The geophysical data were acquired, processed, and interpreted to determine possible locations of larger [total offset greater than 6 ft (1.8 m)], shallow normal faults within the fault zone. Interpretations of the individual data sets were integrated to help eliminate spurious readings and to strengthen the interpretations. Visual methods of integration, along with computer modeling, were chosen for this study. Furthermore, the geophysical data were correlated and integrated with available trench data and surface data. In addition to verifying locations of known faults, the geophysical surveys detected numerous possible additional faults not previously mapped. Of particular interest is a newly discovered graben structure near the southern end of the site, where building of new homes has recently been proposed.
New structural information about fault densities and styles was also determined from the surveys. The fault concentration for this site is 1.3 faults/100 ft (30.5 m), or one fault per 77 ft (23.5 m). Interpreted antithetic faults at the Hobble Creek site account for 65% of the total, while synthetic faults account for 35% with respect to the main fault strand.
Information derived from this study should be useful during planning and development of areas within the Wasatch fault zone. The characteristics of subsurface deformation can be used to gain a better understanding of the potential for surface rupture at a given site. This is also useful in planning appropriate site development and remedial measures to help mitigate hazards associated with large-magnitude earthquakes. 相似文献
8.
The sedimentary basins that dominate the north-eastern Mediterranean (Adana-Cilicia basins in the west and Iskenderun basin
in the east) are located on the flanks of a partly submerged positive structure (a part of the Africa-Eurasia convergence
zone) along which strike-slip faults are evident. This study summarizes the findings of two seismic surveys carried out in
the Alanya-Mersin offshore region. Some 850 km of geophysical survey lines were compiled on these cruises. Based on the results
determined from these surveys, the north and central part of Adana-Cilicia basin can be subdivided into eastern, central and
western structural sub-basins separated by the Ecemiş fault complex in the east and the Anamur-Kormakiti structural high in
the west at the same time. Results of this study also indicate that Ecemiş and Anamur-Kormakiti faults are active. Late Miocene
regional compression was responsible for the compartmentation of this complex into the present arrangement and has initiated
the rotational regime which has governed subsequent tectonic developments, notably the extensional behaviour of the NE-SW
trending Ecemiş and Anamur-Kormakiti faults and the transpressive behaviour of the NNE-SSW trending border fault complex. 相似文献
9.
Geophysical, geotechnical and hydrological investigations of a small landslide in the French Alps 总被引：1，自引：0，他引：1
Geophysical, geotechnical and hydrological surveys were conducted in the French Alps on a small landslide in black marl material to assess the stability. The geophysical survey, consisting of electromagnetic, geo-electric and relative differences in water content.
The data on the basal slip surface, together with geotechnical parameters (cohesion and angle of internal friction), were used to make a stability analysis. This analysis revealed that a groundwater level of 4 m below the ground surface is the critical threshold for reactivating the landslide.
The hydrological investigation, which entailed measurements of saturated permeability and pressure heads, indicated that instability depended on long-term wet conditions with little evapotranspiration. 相似文献
10.
高密度电法评价岩溶地下水分布 总被引：1，自引：0，他引：1
本文利用高密度电法对第四系土层进行了勘查,利用所得到的高密度电阻率反演剖面资料,进行了分析,切片,形成等深度的高密度电阻率勘查反演电阻率平面分布,推断地下水的空间活动规律。对利用高密度电阻率勘查推断地下水的空间活动规律进行了一次有益的尝试,为进一步认识地面塌陷和预防治理提供科学依据。 相似文献
11.
Electrical geophysical surveys in the mode of vertical electrical soundings (VES) and continuous vertical electrical soundings (CVES) were conducted in the León-Chinandega plains, northwestern Nicaragua, in order to obtain detailed information about the geometry of the different hydrogeological layers in the aquifer and depth to the basement. A total of 51 VES were carried out within the plains. The results show a complex structure towards the north east of the area, and the southwestern part of the plains presents a smoother stratification. The geoelectrical measurements and borehole information indicate that the basement topography is characterized by hills and deep valleys with highly variable basement depths. Fifty CVES where done in a smaller area in the center of the plain. The resistivity data yielded considerable information revealing the existence of two main geo-electrical units. The combined interpretation of geological and geophysical data shows an environment typical of sedimentary volcanic coastal plains. The information collected during this investigation provides valuable data for estimating the fresh-water resources of the León-Chinandega aquifer system and for development of a groundwater management plan. 相似文献
12.
D.P. Moseley J.K. Pringle R.B. Haslam S.S. Egan S.L. Rogers R. Gertisser N.J. Cassidy I.G. Stimpson 《Geology Today》2015,31(3):109-115
The geology of the Snowdonia National Park in North Wales comprises a mixture of Lower Palaeozoic shallow marine sediments, acidic igneous rocks and basic intrusions of the Welsh Basin that were subsequently deformed during the Caledonian Orogeny. Thin igneous intrusions are challenging to map due to variable surface exposures, their intrusive origin, structural deformation and burial by glacial sediments. This study used a combination of traditional geological techniques, near‐surface geophysical surveys and remote sensing to detect and map a buried dolerite sheet intrusion. Both simple and mathematical analysis of magnetic anomalies and numerical modelling allowed the dolerite position, depths and target widths to be determined. Results showed that calibrated magnetic surveys can characterize buried igneous bodies in such mountainous environments. 相似文献
13.
海洋物探方法是海洋调查的主要方法,在海上风电地质勘察中得到了广泛的应用。在广东阳江沙扒海上风电场勘察中,通过浅地层剖面结合单道地震,查明了场区覆盖层厚度,绘制了基岩埋深图;采用多波束测深和侧扫声呐,并结合浅地层剖面探测和钻探取样成果查明了海底障碍物分布;通过浅地层剖面,初步查明了研究区浅层气分布范围;将海洋磁法成果绘制成研究区磁场等值线图。根据多波束测深、侧扫声呐、海洋磁法、浅地层剖面和单道地震等海洋物探方法特点,通过广东阳江沙扒海上风电项目,展示了应用海洋物探技术在海上风电勘察领域取得的成果。 相似文献
14.
本文概要回顾了地矿部物探四十年经历早期创业、发展壮大、全面发展三个阶段。队伍达到4万余人的历史。方法上由三类四种基本方法增加至六类40余种常用的方法,一些已跨入国际先进行列。四十年物探圈出了数以百计的油气构造及油气田,勘查出数以千计的金属矿和非金属矿的矿产地,完成了数以万计的水源地与工程环境物探项目,提出了一大批基础地质和深部地质问题的新认识;圈出了近海四个海域油气远景区,并开发了远洋海域大地构造的研究。四十年物探技术方面形成或建立起第二代航空物探技术系统,区域重力调查技术系统,石油地震勘探技术体系,固体矿产深部找矿的物探方法系列,水文、地热、工程、环境物探方法系列,井中物探方法系列,油气、煤田、盐类矿和水文测井系列,海洋物探技术系统,深部地球物理调查方法系列和体系,计算机应用体系。当今,我部具有一支能在空中、地面、地下、海上开展工作,方法齐全,技术配套的队伍,可胜任摆在我们面前的重点工作,即保证区域物探开展,加强急缺矿产物探普查,拓宽水文、工程、环境物探工作领域,大力推动技术进步,努力开发技术市场。 相似文献
15.
Effect and Prospect of Basic Geological Survey Based on Airborne Gravimetry in China 总被引：1，自引：0，他引：1
LI Wenyong ZHOU Jianxin XIONG Shengqing GUO Zhihong LU Wenfen XU Jianchun LIU Yanxu 《《地质学报》英文版》2012,86(1):38-47
The airborne gravimetry was an important leap and innovation in the world’s history of geophysical exploration. China's first test of the airborne gravity geological survey in the onshore-offshore transitional area of the western and southern part of the Bohai Sea was successful and effective in geology. Based on the airborne gravity data, and combining previous ground gravity, seismic and drilling data etc., we carried out the geological interpretation by forward and inverse methods. The result shows that the airborne Bouguer gravity anomaly was clear, the fracture interpretation was reliable, and the inversion depth of the main geological interfaces was relatively accurate. This airborne gravity geological survey not only filled the exploring gaps in the onshore-offshore transitional area, and realized the geological and tectonic junction between the sea and the land, but also discovered four local gravity anomalies, 11 fractures and three sags or subsags, and so on. The good geological effect of airborne gravimetry not restricted by terrain condition shows that it can be served as a new geophysical method in the exploration of complex terrain physiognomy area such as mountain, jungle, desert, marsh, onshore-offshore transitional area and so on, and has an extensive application prospect in China in the future. 相似文献
16.
Mahmut G. Drahor Gökhan Göktürkler Meriç A. Berge T. Özgür Kurtulmuş 《Environmental Geology》2006,50(2):147-155
Electrical resistivity imaging is a widely used tool in near surface geophysical surveys for investigation of various geological, environmental and engineering problems including landslide. In this study, an electrical resistivity tomography (ERT) survey was conducted in a landslide area, located in the Söke district of Aydın, Turkey. In 2003, the Neogene-aged units on the slope next to a newly built school building became unstable due to an excavation work and moved after a heavy rainfall. The resulting landslide partly covered the school. The authors carried out a 2-D resistivity survey along three profiles over the landslide mass using a Wenner configuration. It yielded useful information about the geometry and characteristics of the landslide. In addition, a 2-D synthetic resistivity modelling study was carried out to understand the response of the resistivity method to a landslide problem before the field surveys. Eight boreholes were also drilled in the landslide area. Both the drilling and resistivity results indicated the presence of a fault in the site. Also, the resistivity data from the line measured along the axis of the landslide revealed the surface of rupture. 相似文献
17.
Investigation of waste disposal areas using electrical methods: a case study from Chania,Crete, Greece 总被引：1，自引：0，他引：1
Pantelis Soupios Ilias Papadopoulos Maria Kouli Irene Georgaki Filippos Vallianatos Eleni Kokkinou 《Environmental Geology》2007,51(7):1249-1261
A geophysical investigation of a landfill area was conducted as inextricable phase of a preliminary geotechnical, geological
and hydrogeological study of the area under investigation. Electrical resistivity tomography (ERT), one of the most promising
prospecting techniques mainly concerning its effective contribution to resolve several environmental problems, was applied
for the geophysical modeling. ERT is a robust imaging method the theory and implementation of which are well documented in
geophysical research literature. The survey site is located in Akrotirion Peninsula, about 7 km east of Chania city in Crete
I. The geological setting comprises Trypalion limestones, marly limestones and a clayed weathered layer. Cavities are also
identified at various scales which are recent tectono-karstic voids. Due to the above-mentioned geological singularity and
in the light of the requirement for an environmentally safe construction of the landfill, an ERT survey was carried out. Specifically,
seven geoelectrical tomographies were conducted reaching the prospecting depth of 36 m. The resulted images conduced, to overcome
geotechnical problems since the spatial distribution of karstic voids was determined, to plan the future sites for waste disposal
as the geological conditions were studied in detail and to reliably estimate the thickness of the already deposited wastes.
The resulted images were confirmed using available borehole logs and ambient noise measurements. 相似文献
18.
Meriem Snineh Nour-Eddine Laftouhi Khalid Mehdi Abdenbi El Mandour Abdessamad Hejjaj Laila Mandi 《Environmental Earth Sciences》2018,77(3):102
The Bleida fractured aquifer is not well studied in terms of water resources as previous geophysical investigations in this area were undertaken for mining purposes. This study utilized magnetic resonance sounding surveys in order to define the distribution of water resources in the region of Bleida and to locate areas favorable for the drilling and construction of productive hydraulic boreholes. For this purpose, eight magnetic resonance sounding surveys were conducted in two sites at the intersection of faults in basement rocks. The results of these surveys indicated that there were two distinct levels of saturation in fractured rock that decreased with depth. 相似文献
19.
An interdisciplinary team studied Guajará, a prehistoric artificial mound in the Brazilian Amazon. The geophysical surveys and excavations were interactive;this interaction furnished more information than either geophysics or excavation alone could have provided. While seven different geophysical methods were applied, the magnetic survey reported here was particularly valuable. A detailed interpretation of this survey quantified the magnetic material in the mound, and this furnished an initial estimate of the number of cooking hearths in the mound. Ten test excavations were concentrated at magnetic anomalies. These excavations located cooking hearths and burial urns. A reevaluation of the magnetic survey was then done in order to refine the estimate of the number of hearths in the mound; this yielded an estimate of 2200 hearths. This allowed the population of the site to be approximated at 78–156 people. The geophysical survey and excavations also identified possible locations for subsequent broad‐area excavations. © 2003 Wiley Periodicals, Inc. 相似文献
20.
Archaeologists dealing with earthen forms must distinguish those constructed by humans from those with a natural origin. Geophysical techniques can help identify culturally loaded soils and sediments. We suggest that intrinsic changes in geophysical properties, due to cultural loading, can serve as fingerprints in determining whether a mound or other earthen form is natural or culturally constructed. Culturally emplaced soils might be identified through anomalous values in geophysical properties or through unusual spatial or stratigraphic complexity. The identification of this “lumpiness” in geophysical properties may involve geophysical techniques quite different from those employed in traditional archaeogeophysical surveys. Experiments at three prehistoric mound sites (the Cahokia Mounds State Historic Site, Effigy Mounds National Monument, and the Hopeton Earthwork) illustrate a number of these techniques including studies of the anisotropy (directionality) of geophysical properties, seismic Rayleigh (surface) waves, and magnetic susceptibility. © 2002 Wiley Periodicals, Inc. 相似文献