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As part of the International Geoscience IGCP-715 project, we present the core objective and preliminary analyses on the karst development of the study areas. Our aim is to further characterize the geomorphologic features of the extended karst of Koiliaris Critical Zone Observatory (KCZO), Crete, Greece. Simultaneously to better understand the main drivers of karst development we compare the CKZO karst system with other areas in different tectonic contexts such as Oman (Salma Plateau), the northern UAE and southern China (Guilin karst area).Hydrological studies and previous geomorphologic analysis of KCZO suggest that 27% of the total water budget is coming from the adjacent watershed in the east where an extensive karst system with two explored super-deep caves is situated (Liontari Cave - 1100 m, Gourgouthakas Cave - 1200 m). The area is build up by a continuous carbonate succession exceeding 5 km in depth, lying on top of the Hellenic subduction zone. Field work and Google Earth mapping show two dominantly striking directions of failures (fault, fracture surfaces), trending E-W to ESE-WNW (90-120°) and N-S to NNE-SSE (0-22.5°). The N-S surfaces are mainly fractures while the E-W ones are mainly thrusts and/or strike-slip faults with obvious large displacements of hundreds of meters. The karst development in a subduction zone with dramatic thrusting on the overriding plate has created super-deep caves which are controlled by the vertical bedding and a series of faults and fractures. The area exhibits two layers with different hydraulic properties, a fast water-transferring zone and a slower one which is consistent and supports the hypothesis of the hydrologic model. At the Salma Plateau, in Oman, the karstic system is related to rapid uplifted Eocene limestones that overlay the Semail Ophiolite. There is a large cave (Majilis Al Jinn) at an area of interconnected fractures (and/or faults?). It is the only karstic system presented inhere which has similarities with the karstic system in the KCZO.At the UAE and northern Oman (Musandam) is an active collision zone between Arabia and Eurasia with 2000-m-thick allochthonous Mesozoic limestones. The area lacks a subsurface karst system, and the only karst has developed in steep wadis.Finally, the Guilin area in China represents a former passive margin with a Devonian limestone. It features a spectacular karst of conical peaks (fengcong) and tower peaks (fenglin). Caves exhibit mainly a horizontal development and there is no similarities to the KCZO.

ΣΤΗΝ ΔΙΑΤΡΙΒΗ ΑΥΤΗ ΠΑΡΟΥΣΙΑΖΟΝΤΑΙ ΤΑ ΑΠΟΤΕΛΕΣΜΑΤΑ ΤΗΣ ΚΙΝΗΜΑΤΙΚΗΣ ΑΝΑΛΥΣΗΣ ΚΑΙ ΤΗΣ ΜΕΛΕΤΗΣ ΤΗΣ ΠΑΡΑΜΟΡΦΩΣΗΣ ΤΩΝ ΚΑΛΥΜΜΑΤΩΝ ΤΗΣ ΚΕΝΤΡΙΚΗΣ ΚΡΗΤΗΣ. Η ΜΕΛΕΤΗ ΑΥΤΗ ΣΤΗΡΙΧΘΗΚΕ ΣΤΗΝ ΕΦΑΡΜΟΓΗ ΤΩΝ ΣΥΓΧΡΟΝΩΝ ΜΕΘΟΔΩΝ ΤΗΣ ΤΕΚΤΟΝΙΚΗΣ ΑΝΑΛΥΣΗΣ ΚΑΙ ΕΠΕΞΕΡΓΑΣΙΑΣ. ΕΤΣΙ, ΜΠΟΡΕΣΑΝ ΝΑ ΔΙΑΧΩΡΙΣΤΟΥΝ ΤΑ ΑΚΟΛΟΥΘΑ ΤΕΚΤΟΝΙΚΑ ΓΕΓΟΝΟΤΑ. ΤΟ ΠΑΛΙΟΤΕΡΟ DA, ΕΛΑΒΕ ΧΩΡΑ ΣΤΟ ΑΝΩ ΚΡΗΤΙΔΙΚΟ ΚΑΙ ΣΥΝΔΕΕΤΑΙ ΜΕ ΤΗΝ ΑΝΑΠΤΥΞΗ, ΣΤΑ ΠΕΤΡΩΜΑΤΑ ΤΩΝ ΑΣΤΕΡΟΥΣΙΩΝ, ΣΥΝΘΗΚΩΝ ΟΜΟΑΞΟΝΙΚΗΣ ΕΚΤΑΣΗΣ ΚΑΙ ΜΙΑΣ ΥΨΗΛΗΣ ΘΕΡΜΟΚΡΑΣΙΑΣ, ΜΕΤΑΜΟΡΦΩΣΗ. ΤΟ ΕΠΟΜΕΝΟ DB, ΕΛΑΒΕ ΧΩΡΑ ΠΙΘΑΝΟΝ ΣΤΟ ΠΑΛΑΙΟΚΑΙΝΟ ΗΩΚΑΙΝΟ ΚΑΙ ΣΥΝΔΕΕΤΑΙ ΜΕ ΜΙΑ ΔΙΑΔΙΚΑΣΙΑ ΥΠΟΒΥΘΙΣΗΣ ΠΛΑΚΩΝ ΚΑΙ ΤΗΝ ΜΕΤΑΜΟΡΦΩΣΗ ΤΩΝ ΠΕΤΡΩΜΑΤΩΝ ΥΨΗΛΗΣ ΠΙΕΣΗΣ ΤΟΥ ΠΡΕΒΕΛΗ. ΤΟ DO ΓΕΓΟΝΟΣ ΕΠΗΡΕΑΣΕ ΟΛΑ ΤΑ ΑΝΩΤΕΡΑ ΚΑΛΥΜΜΑΤΑ ΤΗΣ ΚΡΗΤΗΣ ΚΑΤΑ ΤΟ ΑΝΩ ΗΩΚΑΙΝΟ - ΚΑΤΩ ΟΛΙΓΟΚΑΙΝΟ, ΠΡΟΚΑΛΩΝΤΑΣ ΜΙΑ ΠΡΟΣ ΤΑ ΔΥΤΙΚΑ ΛΕΠΙΩΣΗ ΚΑΙ ΤΗΝ ΔΗΜΙΟΥΡΓΙΑ ΤΟΥ ΤΕΚΤΟΝΙΚΟΥ "MELANGE". ΣΤΟ ΑΝΩ ΟΛΙΓΟΚΑΙΝΟ - ΚΑΤΩ ΜΕΙΟΚΑΙΝΟ, ΤΟ D1 ΓΕΓΟΝΟΣ ΠΡΟΚΑΛΕΣΕ ΤΗΝ ΠΡΟΣ ΝΟΤΟ ΤΟΠΟΘΕΤΗΣΗ ΟΛΩΝ ΤΩΝ ΚΑΛΥΜΜΑΤΩΝ ΚΑΙ ΤΑΥΤΟΧΡΟΝΑ ΤΗΝ ΥΠΟΒΥΘΙΣΗ ΚΑΙ ΜΕΤΑΜΟΡΦΩΣΗ ΣΕ ΣΥΝΘΗΚΕΣ ΥΨΗΛΗΣ ΠΙΕΣΗΣ, ΤΩΝ ΚΑΤΩΤΕΡΩΝ ΚΑΛΥΜΜΑΤΩΝ. ΣΤΟ ΜΕΙΟΚΑΙΝΟ ΑΚΟΛΟΥΘΗΣΕ Ο ΟΜΟΑΞΟΝΙΚΟΣ D2 ΕΦΕΛΚΥΣΜΟΣ, ΠΟΥ ΣΥΝΔΕΕΤΑΙ ΜΕ ΤΗΝ ΔΗΜΙΟΥΡΓΙΑ ΡΗΓΜΑΤΩΝ ΑΠΟΚΟΛΛΗΣΗΣ, ΤΗΝ ΚΑΤΑΡΕΥΣΗ ΤΩΝ ΚΑΛΥΜΜΑΤΩΝ ΚΑΙ ΤΗΝ ΑΠΟΚΑΛΥΨΗ, ΤΩΝ ΚΑΤΩΤΕΡΩΝ, ΜΕΤΑΜΟΡΦΩΜΕΝΩΝ ΣΕ ΣΥΝΘΗΚΕΣ ΥΠ, ΚΑΛΥΜΜΑΤΩΝ. ΜΙΑ ΔΕΥΤΕΡΕΥΟΥΣΑ D3 ΣΥΜΠΙΕΣΗ ΕΛΑΒΕ ΧΩΡΑ ΣΤΟ ΑΝΩ ΜΕΙΟΚΑΙΝΟ. Η ΜΕΛΕΤΗ ΑΥΤΗ ΕΔΕΙΞΕ ΕΠΙΣΗΣ ΟΤΙ Η ΓΕΩΛΟΓΙΚΗ ΕΞΕΛΙΞΗ ΤΗΣ ΚΡΗΤΗΣ ΕΙΝΑΙ ΣΤΕΝΑ ΣΥΝΔΕΔΕΜΕΝΗ ΜΕ ΑΥΤΗΝ ΤΩΝ ΚΥΚΛΑΔΩΝ.

We present new Raman spectra data of carbonaceous material (CM) to extend the range of the Raman spectra of CM thermometer (RSCM) to temperatures as low as 100 8C. Previous work has demonstrated that Raman spectroscopy is an excellent tool to describe the degree of graphitization of CM, a process that is independent of pressure but strongly dependent on metamorphic temperature. A linear relationship between temperature and the Raman parameter R2 (derived from the area of the defect band relative to the ordered graphite band) forms the basis of a previous thermometer. Because R2 shows little variability in low-temperature samples, 330 8C serves as a lower limit on the existing thermometer. Herein, we present Raman spectra from a suite of low-temperature (100 to 300 8C) samples from the Olympics Mountains and describe other aspects of the Raman spectra of CM that vary over this range. In particular, the Raman parameter R1 (the ratio of heights of the disordered peak to ordered peak) varies regularly between 100 and 350 8C. These data, together with published results from higher-temperature rocks, are used to calibrate a modified RSCM thermometer, applicable from 100 to 700 8C. Application to low-grade metasediments in the Otago region in the South Island of New Zealand gives temperatures consistent with previous estimates, demonstrating the reliability of the modified RSCM thermometer. We apply the modified RSCM thermometer to 53 samples from Crete to evaluate the role of the Cretan detachment fault in exhuming Miocene high pressure/low-temperature metamorphic rocks exposed there. The metamorphic rocks below the detachment (the Plattenkalk and Phyllite–Quartzite units) give metamorphic temperatures that range from 250 to 400 8C, consistent with previous petrologic estimates. We also demonstrate that the Tripolitza unit, which lies directly above the detachment, gives an average metamorphic temperature of about 260 8C. The modest break in metamorphic temperature in central Crete indicates that the Cretan detachment accounts for only 5 to 7 km of exhumation of the underlying HP–LT metamorphic rocks, which were initially accreted at ~35 km. We argue that the bulk of the exhumation (~28 km out of 35 km total) occurred by pervasive brittle stretching and erosion of structural units above the detachment. D 2005 Elsevier B.V. All rights reserved.

In this paper we present new geological and seismological data on the orientation of crustal extension in central Crete (SE Heraklion basin) following the occurrence of two shallow seismic sequences: a) the May 2005 Assimi M=4.1 earthquake sequence and b) the 2013 Houdetsi-Tefeli sequence (3.2≤Mw≤3.6). Emphasis is given to the results of the geological field work, stress analysis, source inversion, aftershock relocations and mapping of earthquake-induced environmental effects. For the first time we find seismological evidence for N-S strike-slip motions along shallow fault planes in central Crete (Amourgeles fault). Our results indicate that while crustal extension dominates there is a combination of active fault kinematics, ranging from normal faulting along the northern edge of Messara basin (south-dipping Plakiotissa fault) to strike-slip faulting inside the SE part Heraklion basin (Houdetsi-Tefeli). The combination of active fault motions accommodates a NW-SE extension of the upper crust.

Recent work ( Carcaillet et al., 2008 , Manighetti et al., 2010 ) has utilised a well-established earthquake record on a normal fault in Italy (the Magnola Fault) to successfully test a new method for identifying paleoearthquakes on carbonate rocks: that of chemical analysis of their exhumed fault planes. Here we take the next natural step, applying this novel method on a notionally active normal fault in Greece, the Spili Fault, for which no paleoearthquake record exists. Despite the ‘blind’ sampling, data reveal an outstanding record of systematic fluctuations in the concentrations of Rare Earth Elements (REE) and Yttrium (Y) upscarp, which closely resemble those recorded on the Magnola Fault. Chemical analysis of 35 core-samples extracted from a 10 m high section of the exhumed Spili Fault plane records upscarp depletion in the REE-Y concentrations at an average rate of ca. 9.3%/m. Depletion is overprinted by locally increased REE-Y concentrations upscarp. A minimum of four such concentration fluctuations, with wavelengths ranging from 0.5 to 3 m, are recorded. Each fluctuation is interpreted to be generated by at least one paleoearthquake that episodically exhumed a zone of the fault plane. Each zone consists of an upper domain that is enriched in REE-Y and a lower un-enriched domain. REE-Y enrichment is due to the prolonged (at least few 100's of years) contact of the limestone with the soil, whereas the un-enriched domain reflects instantaneous uplift from depths greater than the base of the soil, during the same earthquake. The REE-Y analytical method cannot resolve individual small-sized earthquakes (with slip less than the thickness of the soil-cover) and/or individual large- and small-sized earthquakes which are clustered in time (repeat time