Areas Of Cyprus Research Articles

Tick paralysis induced by Ixodes gibbosus: enigmatic cases in domestic mammals from Cyprus.

Tick paralysis is a potentially fatal condition caused by toxins produced and secreted by tick salivary glands. This survey presents clinical and epidemiological observations of tick paralysis cases in domestic animals in Cyprus. Local veterinarians report typical tick paralysis cases occurring in goats, sheep, dogs, and cats. The animals suffering from paralysis are free from other neurological diseases, have blood and biochemical parameters within normal ranges, and recover fast by simply removing the ticks found predominantly on the head and around the neck. Tick paralysis cases occur in a specific geographic area of Cyprus (Akamas peninsula), from September through March, but not every year. Instead, the phenomenon has 2 periodic cycles of occurrence, a 3- and a 7-year cycle. The 2 cycles are differentiated by severity based on the number of affected animals and the resulting losses. As described for other tick-borne diseases, these cyclic patterns may be attributed to external factors, self-oscillations of the disease system, or the combined action of these mechanisms. Ticks collected from a recent paralysis case in a goat were morphologically and molecularly identified as Ixodes gibbosus. Efforts should be made to characterize the specific toxins involved in tick paralysis and to develop a vaccine, which could prevent significant losses of small ruminants, especially in free-ranging farming systems, a prevalent management approach observed in Cyprus and various regions worldwide.

Everlasting divorce? The temporal scope of the UK Withdrawal Agreement

The purpose of this article is to examine and to provide a tentative temporal scope of the UK Withdrawal Agreement with a focus on the maximal time limits for its application. It begins with an analysis of the nature of the agreement and its impact on the temporal scope. Subsequently, a temporal scope is explored with respect to the core provisions of the agreement (citizens’ rights, financial settlement, various separation provisions, and dispute settlement) and the three protocols addressing the situation in Ireland/Northern Ireland, Gibraltar and the Sovereign Base Areas in Cyprus. The focus is laid on determining the approximate time limits for the application of both the core provisions and the protocols. Their temporal scope is derived from their nature and an appropriate explanation to this effect is provided.

Environmental heterogeneity and lizard assemblages in riparian areas in Cyprus

The island of Cyprus hosts a rich diversity of reptiles, including several endemic species. Reptiles are morecommon in Mediterranean-type shrubland and other open habitats in Cyprus, although riparian formations offeradditional cover and food sources, especially during dry, hot summers. Riparian habitats are often very heterogeneous,an attribute that can be important for lizards since they can utilize a variety of microhabitats crucial for different aspectsof their ecology. Nevertheless, reptilian diversity in riparian systems remains understudied and Cyprus is no exception.The aim of this study was to compare lizard diversity and abundance patterns across seasons and elevations, as well astheir relationships with habitat heterogeneity and protected status of areas along riverbanks, as expressed by presencein or out of Natura 2000 sites. We examined the effects that these factors can have on lizard communities by studyingthree rivers that exhibit variations in environmental conditions. Additionally, we evaluated separately the abundancesof four common species (Snake-eyed Lizard, Ophisops elegans; Troodos Rock Lizard, Phoenicolacerta troodica; CyprusRock Agama, Laudakia cypriaca; and Schreiber’s Fringe-toed Lizard, Acanthodactylus schreiberi) while recording in riparian habitats seven of the 11 Cypriot species of lizards. Diversity and richness were not significantly associated withany of the explanatory variables examined (season, elevation, habitat heterogeneity, and protected status). Moreover,we found no relationship between the abundances of each of the four species and habitat heterogeneity, even thoughthey responded differently to elevation, season, and protected status. Our results suggest that lizard diversity in ripariansystems is high compared to the total number of lizard species found on Cyprus, reaching 60% of the overall richness.

Lead, cadmium and mercury determination and human health risk assessement in foods from Cyprus

An accredited method using inductively coupled plasma mass spectrometry was applied for the determination of lead, cadmium and mercury in food. Up to 96% of the samples were contaminated with at least one of the three metals. Concentrations ranged between 0.003 and 0.045 mg kg–1, 0.0007 and 0.38 mg kg–1, 0.002 and 0.32 mg kg–1 for lead, cadmium and mercury respectively. No health risk was concluded from the dietary exposure assessment to lead. Less than 1% of the Cyprus population was found to exceed the health-based guidance value (Tolerable Weekly Intake, TWI), as regards to mercury. However, 9 to 15% of the younger population in Cyprus exceeded the TWI for cadmium intake. Dietary exposure to heavy metals was found to be independent of the geographical area in Cyprus and gender. Exposure to lead was a result of the consumption of several food categories. Molluscs (21%) and potatoes (18%) were the highest contributors to cadmium intake. In the case of mercury, fish (25%), meat (21%) and milk (12%) contributed the most to the total exposure of the population in Cyprus.

An updated 3D crustal velocity model in Cyprus by non-linear traveltime tomography

We have used >6000 regional earthquakes in the broader Cyprus island area, with 100,000+ P and S-phases recorded by 26 local seismological stations to obtain a 3D velocity model for the Cyprus area using a non-linear seismic tomography approach. Due to the limited aperture of the recording network, the tomographic model mainly recovers the dominant geophysical features of the upper crust of the Cyprus island. The obtained results reveal new information on the 3D structure of the Troodos ophiolithic complex, identifying a high velocity anomaly that coincides with the NW-SE trending ophiolitic units of the Troodos mountain. Furthermore, they clearly show that the anomaly associated with the ophiolite zone of Troodos is well preserved up to a depth of at least 10 Km, dipping towards the Northeast. The Mesaoria basin in central Cyprus is recognized as a large low-velocity feature, with the results suggesting a significant thickness of the basin, exceeding 5 km. A similar low-velocity pattern can be observed for the Circum Troodos formations (Pakhna and Lefkara) to the southwest of the Troodos mountain, while the Kyrenia range is not associated with a crustal velocity anomaly. To assess the reliability of the results we have conducted checkerboard resolution tests, which suggest that the uppermost crustal features are well reconstructed, while for larger depths (>10 km) we cannot recover mid-crustal anomalies due to the insufficient traveltime data coverage and quality (e.g., traveltime picking errors).

The Relationship Between Parental Knowledge and Adolescent Delinquency: a Longitudinal Study

The purpose of the present study was to test the direction of effect in the relationship between parents’ sources of knowledge (parental monitoring and child disclosure) and adolescents’ delinquency. The participants were 157 8th and 9th grade students and their mothers, randomly selected from urban and rural areas in Cyprus. A six-month, two-timepoint longitudinal design was used in which adolescents completed the delinquency scale while mothers completed the parental knowledge questionnaire. The results of this study showed that child disclosure at Time 1 predicted a decrease in both major and minor delinquency at Time 2 whereas adolescent major delinquency at Time 1 predicted a decrease in child disclosure and parental monitoring at Time 2. Contrary to previous wide-held assumption, parental monitoring at Time 1 did not significantly predict a decrease in delinquency at Time 2.

Management Implications at a Protected, Peri-Urban, Salt Lake Ecosystem: The Case of Larnaca’s Salt Lakes (Cyprus)

Larnaca’s salt lakes constitute one of the most important protected areas in Cyprus and in the southeast Mediterranean. It is in continuity with the urban area of Larnaca city, being the major green infrastructure in the area, supporting (among others) biodiversity, recreation, culture, and food production. The present study aims to provide an overview of the area’s ecosystem types and their potential to provide ecosystem services, focusing on assessing the water ecosystem condition and drafting the relevant baseline accounts. The results of the study include an ecosystem type map of the area, followed by potential supply maps of ecosystem services, for the three major categories (i.e., provisioning, regulating and maintenance, and cultural) and the estimation and assessment of ecosystem condition variables for wetlands, as proposed by the EU-wide methodology to map and assess the ecosystem condition, in line with the System of Environmental Economic Accounting—Ecosystem Accounting (SEEA EA). A critical exceedance (over 10%) of the imperviousness and the increase in the soil moisture deficit within the wider salt lakes area have been identified and can constitute useful variables associated with the anthropogenic, climatic, and other effects on the condition of the salt lakes. Discussion for integrating this information to existing knowledge is provided toward supporting scientifically informed decision and policymaking for the sustainable development of protected areas.

HS-SPME-GC-MS analysis of Cyprus vineyard soil for VOCs determination

In line with green chemistry principles, a headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) method was developed and optimized to study the profile of biogenic volatile organic compounds (BVOCs) in soil samples from vineyards. The 75 µm CAR/PDMS fiber was selected for the identification of BVOCs in soil. The analytical method showed very good linearity (R2 ≥ 0.9914), sensitivity, and precision. Subsequently, soil matrix effect (ME) was examined on the BVOCs emission, through combined standard addition and internal standard (IS) calibration curves. The validated and optimized method was further applied in real soil samples from three vineyard areas of Cyprus (Omodos, Polemi, and Agros). Thirty-eight BVOCs were identified in total; among them acetone (0.65–5.96 μg/kg), hexane (0–0.50 μg/kg), heptane (0–0.18 μg/kg), trichloromethane (0.13–0.21 μg/kg), 1,2-dichloropropane (0.05–1.37 μg/kg), cyclohexane (0–0.26 μg/kg), benzene (0–0.51 μg/kg), toluene (0–0.54 μg/kg), p-xylene (0.15–0.97 μg/kg), and 1,3-di-tert-butyl-benzene (7.91–29.55 μg/kg) were quantified. The results revealed that the sampling vineyard location affects the BVOCs emissions in each soil. Also, vineyard elevation, soil pH, Ca, N, Zn, and Fe showed a significant correlation with the BVOCs emissions, which explains why vineyard soil regions are distinguished from each other, concluding that sample from Agros is the most abundant in BVOCs emissions.

Pest categorisation of Paracoccus marginatus.

The EFSA Panel on Plant Health performed a pest categorisation of Paracoccus marginatus (Hemiptera: Sternorrhyncha: Pseudococcidae), the papaya scale, for the EU. It is native to Central America and since the 1990s, it has spread rapidly in mainly tropical areas of the Caribbean, islands in the Indian and Pacific Oceans, Africa and southern Asia. Large populations were detected in northern Israel in 2016. It has not been reported within the EU. It is not listed in Annex II of Commission Implementing Regulation (EU) 2019/2072. It reproduces sexually and there are up to 11 generations per year in India. The estimated minimum, optimum and maximum temperature thresholds for the adult females are 13.9, 28.4 and 32.1°C, respectively. First-instar nymphs may move to neighbouring plants by crawling, or be passively dispersed by wind, or hitchhiking on clothing, equipment or animals. It is highly polyphagous, feeding on plants in 172 genera and 54 families. It is an important pest of custard apple (Annona spp.), papaya (Carica papaya) and Hibiscus spp. It also feeds on a wide range of plants cultivated in the EU such as eggplant (Solanum melongena), avocado (Persea americana), citrus (Citrus spp.), cotton (Gossypium hirsutum), grapevine (Vitis vinifera), guava (Psidium guajava), mango (Mangifera indica), passionfruit (Passiflora edulis), pomegranate (Punica granatum), pepper (Capsicum annuum) and tomato (Solanum lycopersicum). Plants for planting, fruits, vegetables and cut flowers are the main potential pathways for entry of P. marginatus into the EU. Climatic conditions in the warmest areas of Cyprus, Greece, Italy and Spain, where host plants occur, would likely allow this species to successfully establish and spread. Reductions in yield and quality of some cultivated hosts including Annona spp., Hibiscus spp. and papaya are anticipated if establishment occurs. Phytosanitary measures are available to reduce the likelihood of entry and spread. P. marginatus meets the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest.

Prevalence and Characteristics of Self-Reported Adult Asthma in Cyprus: A Population-Based Observational Study.

To estimate the prevalence of asthma in adults, by gender and age, in urban and rural areas of Cyprus. This was a population-based, random-digit dialing, telephone nation-wide survey to recruit patients with asthma. Among 8996 random landline-telephone contacted from the five major urban and rural regions of Cyprus, 1914 were finally met the age criterion of ≥18 years old and 572 completed valid screening for prevalence estimation. The participants filled a short screening questionnaire in order for asthma cases to be recognized. Then, asthma cases filled the main ECRHS II questionnaire and were evaluated by a pulmonary physician. All underwent spirometry. Data on demographic characteristics, educational level, profession, smoking status, Body Mass Index (BMI), Total IgE and Eosinophil Cationic Protein levels were measured. The overall prevalence of bronchial asthma in adults in Cyprus was 5.57% (61.1% men and 38.9% women). Among the participants with self-reported bronchial asthma 36.1% were current smokers, while 12.3% were obese (BMI >30). A total value of IgE >115 IU and Eosinophil Cationic Protein (ECP) >20 IU was found in 40% of the participants with established bronchial asthma. Wheezing and chest tightness were the most frequently reported symptoms in asthma patients (36.1% and 34.5%, respectively), while 36.5% experienced at least one exacerbation during the last year. Interestingly, most of the patients were under-treated (14.2% were on maintenance asthma treatment, and 18% used solely reliever medication). This was the first study estimating asthma prevalence in Cyprus. Asthma affects almost 6% of the adult population, with higher prevalence in urban areas and in men compared to women. Interestingly, one-third of the patients were uncontrolled and under-treated. This study revealed that in Cyprus there is space for improvement in the management of asthma.

LCA of Barley Production: A Case Study from Cyprus.

Greenhouse gas emissions (i.e., carbon dioxide, methane, nitrous oxide) produced by agriculture contribute to global warming and climate change. Various practices followed by farmers in different environmental conditions contribute to the increase in the phenomena, and there is a need for immediate measures. The current study examines the environmental impact of barley production under rain-fed conditions in Cyprus. For this, four different nutrient management scenarios were investigated in order to evaluate the environmental performance of crop production, namely: (1) Nitrogen (20%), Phosphorous (20%), Potassium (10%); (2) Nitrogen (20%), Phosphorous (20%), Potassium (10%) and manure; (3) Nitrogen (25%), Phosphorous (10%), Potassium (0%); and (4) Nitrogen (25%), Phosphorous (10%), Potassium (0%) and manure. Data were collected from two different areas of Cyprus (Nicosia and Larnaca) through on-site visits and questionnaires. Life Cycle Assessment (LCA) was used as a method to quantify environmental impacts which were categorized into six impact categories: (i) acidification potential (AP), (ii) eutrophication potential (EP), (iii) global warming potential (GWP), (iv) ozone depletion potential (ODP), (v) photochemical, ozone creation potential (POCP), and (vi) terrestrial ecotoxicity (TAETP). LCA was used with system boundaries from field to harvest and a functional unit (FU) of one bale of hay. Research results showed that the addition of manure increased values in all impact categories. Comparing scenarios without manure (1 and 3) and with manure (2 and 4), the main process which contributed to GWP was field preparation, which resulted in 3 t CO2-Eq∙FU-1 and 46.96 t CO2-Eq∙FU-1, respectively. Furthermore, the highest contribution of sub-processes to GWP (kg CO2-Eq∙FU-1) was machinery maintenance (scenarios 2 and 4). The potential to reduce environmental impacts from barley and moreover, to mitigate the footprint of the agriculture sector in Cyprus is proposed by changing existing practices such as decreasing fuel consumption by agricultural machinery, and monitoring fertilizing and seeding. Conclusively, the carbon footprint of barley can be decreased through the improvement of nutrient management and cropping practices.

Capillary absorption into CEBs and 2-layer composite building materials comprising of natural stone and CEBs

Earth-based building materials have been used since antiquity for the construction of various structures. The main drawback of these materials is their vulnerability to direct contact with liquid water, such as rising damp. To protect earthen structures from rising damp, a stone foundation was used, resulting in composite masonry. In the current study, an experimental investigation of the capillary absorption of non-stabilized CEBs produced with soils sourced from different areas of Cyprus, as well as of 2-layer composite building materials comprising of natural stone and CEBs was carried out. The tests on CEBs indicated that the use of water as the wetting liquid led to the disintegration of the specimens and consequently to non-linear response. Thus, a non-reactive liquid was used instead to measure the capillary absorption coefficient of the materials. The test results showed that the capillary absorption coefficient of CEBs varied between 140-260 gr/m2sec1/2. In the case of the composites, capillary absorption with water as the wetting liquid showed perfectly linear response, following the t1/2 law, with no disintegration of the specimens. The results showed that there are two distinct capillary absorption branches with different gradients, in line with the theory of capillary absorption into 2-layer composite materials.

Two invasions at once: update on the introduction of the invasive species Aedes aegypti and Aedes albopictus in Cyprus - a call for action in Europe.

Aedes aegypti, the yellow fever mosquito and Aedes albopictus, the tiger mosquito, continue to expand their geographical distribution, reshaping the European epidemiological risks for mosquito-borne diseases. The reintroduction of Aedes aegypti near the airport and port in Larnaka and the detection of Aedes albopictus near the marina and old port of the Limassol area in Cyprus are reported herein. The measures taken to investigate these events included (i) communication to health authorities, (ii) expert on-site visits and verification of findings, (iii) enhanced active surveillance, and (iv) development of an Emergency Action Plan followed by a Contingency Plan. These emergency action plans were developed to delimitate the infested areas and to prevent the spreading of the mosquito populations into new areas. The general principles are presented along with their rationale to serve as guidelines for other geographical regions targeting suppression/eradication with a sterile insect technique component. In parallel, this manuscript serves as a call for action at the European level to impede the further spread of these species and support the activities being undertaken in Cyprus to combat the incursions of Aedes invasive species.

Multilingual linguistic landscape of Cyprus

ABSTRACT The topic of linguistic landscapes (LLs) is very important in the area of sociolinguistics of multilingual societies. A linguistic landscape reflects the underlying ideologies regarding languages and their speakers, linguistic diversity, language statuses and perceived values. This study investigated multilingual LL of Cyprus under the conceptual framework of Geo–semiotics by implementing an in–depth qualitative and quantitative landscape analysis of visible semiotic signs in public space, trying to interpret their indexicality and deeper layers of meaning in relation to multilingualism situation in the country, the link between discourse and space, as well as the perceptions and attitudes of the Greek Cypriot population towards multilingualism and multilingual LL. We used photographic material in our data collection – 4,200 photos of all geographical areas of Cyprus, which were analysed quantitatively and qualitatively and interpreted in terms of language, arrangement of displayed text and images, LL genre, visual semiotics, placement and surroundings in line with the principles of the symbolic construction of the public space. It was found that sign readers have a positive attitude towards multilingualism and multilingual signs in Cyprus and that the LL in Cyprus is complex and unique and is related to the political economy of language and space.

Assessment of indoor and outdoor air quality in primary schools of Cyprus during the COVID–19 pandemic measures in May–July 2021

Combined pollutant effects from indoor and outdoor sources on children's health, while being at school have not been holistically tackled. The aim of the School Temperature and Environmental Pollutants Study (STEPS) was to perform a school population representative assessment of indoor air quality (IAQ) in primary schools of densely and intermediate populated areas of Cyprus (n = 42). The study took place during May–July 2021 when a school-specific COVID-19 protocol was in place. Questionnaire-based characteristics of schools/classrooms were collected along with 24/48-h long IAQ monitoring of air temperature, relative humidity (RH), particulate matter (PM), carbon dioxide (CO2) and volatile organic compounds (VOCs), using low-cost sensors. Mixed effect models assessed the IAQ determinants during school hours. Indoor PM, temperature, RH and VOCs increased with progressing school periods in the day, while indoor CO2 decreased. Indoor RH and CO2 were negatively associated with % open windows, while indoor PM2.5 was positively associated. Most of school time (85%), indoor air temperature exceeded the recommended upper limit (27 °C), while a third of indoor PM2.5 (24-h) measurements exceeded 15 μg/m3. The interplay of clean indoor air with adequate ventilation and adaptation to heat stress in schools is important and its comprehensive characterization requires holistic methodological approaches and tools.

The Eastern Mediterranean fish fauna from the Piacenzian deposits of Polis Graben (Cyprus Island)

Marine Piacenzian deposits are extremely rare in the eastern Mediterranean region, resulting in a stratigraphic gap in our knowledge of the late Pliocene evolution of the marine ecosystem and its fauna. Fish assemblages moreover are scant throughout the Pliocene. We present here the teleost fish fauna of the Piacenzian Polis basin (SW Cyprus) based on otolith assemblages, and we use them to reconstruct the paleoenvironment. Twenty-six teleost fish taxa are identified, placed under sixteen genera and five families. Planktonic foraminifera biostratigraphy places the studied outcrop within the subzones MPL4a and MPL5a (early–middle Piacenzian). Four species and two genera of fish are reported for the first time in the Piacenzian of the Mediterranean. The studied otolith assemblage from Androlykou section consists of very shallow-water fish mixed with mesopelagic taxa indicating topographical steepness with easy access to the open ocean. In addition, the fish assemblages mainly include representatives of subtropical taxa suggesting a climate warmer than today. These data provide new information on the composition of the ichthyofauna of the eastern Mediterranean during the Piacenzian, paving the way for new studies in the Cyprus area.

A Small Island With Big Differences? Folk Perceptions in the Context of Dialect Levelling and Koineization

This paper presents the results of the first study within a perceptual dialectology framework in the Greek-speaking community in Cyprus. Thirty participants from three age groups of equal size took part in a sociolinguistic interview. As part of the language module component of the interview, they discussed their beliefs about regional variation in Cyprus and completed the so-called ‘draw-a-map task’. All participants were residents of urban areas of Nicosia, the capital of Cyprus. The Greek-speaking community in Cyprus is diglossic: Standard Modern Greek is the High variety, while Cypriot Greek—the mother tongue of Greek Cypriots—is the Low variety. The latter is currently undergoing levelling of marked local basilect features and subvarieties. A quantitative analysis of the maps demonstrates that some areas in Cyprus (mainly in the periphery) have a stronger sociolinguistic salience than others. At the same time, the participants’ own way of speaking is perceived as unmarked, neutral and one that enjoys wider acceptance over other regional dialects. This study also shows a clear preference for characterizing a (presumed) dialect area with linguistic characteristics, rather than with evaluative commentary contra many similar studies in the literature and suggests a number of reasons why this may be so. Overall, this research shows how studies on language perception can inform and complement studies on language production in a given community. The participants drew an average of just four regional areas on their maps and viewed the different cities and their districts, or combinations thereof, as the different regional dialect areas they perceive to exist in Cyprus. It is argued in this paper that the small number of areas drawn and the emphasis on urban sites are consistent with regional dialect levelling. Consistent with regional dialect levelling is also the finding that the participants’ linguistic description of regional variation, while mainly accurate, is superficial and lacks detail. Interestingly, many of the participants also seem to be well aware of regional dialect levelling in their community. Other studies in the literature do not really discuss speakers’ awareness of levelling and this should be further explored in future studies.

Multidisciplinary Approaches to Food and Foodways in the Medieval Eastern Mediterranean Edited by Sylvie Yona Waksman (Archéologies 4). Lyon: Maison de l’Orient et de la Méditerranée 2020. Pp. 508. €65. ISBN 978-2-35668-070-9 (paper).

<i>Multidisciplinary Approaches to Food and Foodways in the Medieval Eastern Mediterranean</i> Edited by Sylvie Yona Waksman (Archéologies 4). Lyon: Maison de l’Orient et de la Méditerranée 2020. Pp. 508. €65. ISBN 978-2-35668-070-9 (paper).

Gravity for Lithosphere Architecture Determination and Analysis: the Central Eastern Mediterranean case study

ABSTRACTThe Central‐Eastern Mediterranean region is known to be a complex area due to the interaction of four tectonic plates, namely Arabia, Africa, Anatolia and Eurasia, and by the presence of an ancient oceanic crust in the Herodotus and Ionian Basins. The analysis of the available literature highlights that the distribution of the freely available geophysical data (i.e. seismic, gravity and magnetic observations) is quite disparate. In this framework, high‐resolution global gravity field models, such as XGM2019e, mainly based (offshore) on satellite data, can be profitably used as a uniform dataset to study, in a coherent way, large regions.In the current work, we exploit the XGM2019e model, together with a set of a priori information, derived mainly from geophysical data retrieved from the literature, to study the structure of the crust in the Central‐Eastern Mediterranean area. The study is organized in three different phases: in the first one, we enhanced the map of geological crustal provinces by means of an automatic Bayesian classification algorithm applied to the second radial derivatives of the gravitational potential. In the second phase, using as observation a grid of gravity anomalies, we applied a full three‐dimensional inversion procedure (always based on a Bayesian paradigm) to estimate the mass density variations and the geometries of the main geological units in the whole study area. Finally, in the third phase, we performed a refined three‐dimensional local inversion on the Cyprus area to improve the modelling of the shallowest layers. The main results of this study, carried out in the framework of the European Space Agency GIADA project, are freely available, upon request, at https://www.g‐red.eu/geophysics/.

Problems With Net Tectonic Rotation for Dikes and Suggestions for Alternative Approaches

AbstractThe net tectonic rotation method is an alternative to paleomagnetic tilt corrections. The method was originally developed for sedimentary rocks and lavas, which have paleohorizontal indicators, but was later adapted for dikes by assuming that dikes intrude vertically. We conduct multiple numerical experiments that demonstrate geometric flaws in the net tectonic rotation method if dikes are not quite vertical prior to deformation. These flaws can impact the interpretations from the method, but the size of the impact depends on the original dike strike, dike dip, and the paleomagnetic reference direction. Our experiments show the worst behavior occurs for dikes that are approximately perpendicular to the reference declination. In addition, the results for dipping dikes of all initial strikes become increasingly distorted as the reference direction's inclination increases. Using data from two field areas in Cyprus and northern Iceland, we compare the application of net tectonic rotation to alternative techniques—relative comparisons and spatial regressions—that do not require an assumption of initially vertical dikes. We conclude with a list of questions that workers should answer prior to future application of net tectonic rotation to dikes.