SEDIMENTS AND AGE OF TERRACES AND FLOODPLAINS OF THE EZOUSAS RIVER IN SW CYPRUS

Since 2014 Jan Kochanowski University in Kielce participate in the research in Paphos region in SW Cyprus. The aim of geomorphologic study was the age and sediments of terraces and floodplains in Ezousas river valley. Results of TL dating indicate distinct differentiation in fluvial activity in the Late Pleistocene and Holocene. Two main alluviation phases were distinguish: 75-48 ka and 25-13 ka. Relief and the varied tectonic movements had a great impact on the valley formation and alluvial features.


INTRODUCTION
Cyprus is located in the eastern part of the Mediterranean Sea, in the Mediterranean zone, which is a clearly distinguished physicgeographical region (Fig. 1). In contrast to the rest of the eastern Mediterranean, the island is located between the Anatolian Plateau and the foreland of the African Plate. This area is characterized by high neotectonic activity, varied relief and subtropical climate. The uplift rate of Paphos region, calculated from the high of MIS 7 and MIS 5 uplifted maritime terraces, is 0.35-0.39 mm/year during the Upper Pleistocene [2]. The study area covers the Ezousas river basin (Fig. 2). The spring of the river is located in the Troodos Mountains and the estuary in the Mediterranean Sea, some kilometers to the east from the Paphos city.

AIM OF STUDY AND METHODS
The research was conducted in 2014-2018 [3]. The aim of geomorphologic study was the age and sediments of terraces and floodplains in Ezousas river valley [4], [5], [6], [7], [8], [9]. The geomorphologic prospections were carried out along the Ezousas river valley from the sea to the spring. The field work included geological mapping and sedimentological analysis of sandy gravel alluvium of various terrace and flood plain levels.
Grain size field analysis based on Rutkowski's method [10], [11], petrographic analysis using a polarized light microscope and 21 samples for TL/OSL dating were also done. Dating of alluvium by TL method was conducted in the Scientific-Didactic Laboratory of the Institute of Geography and Environmental Sciences of Jan Kochanowski University in Kielce.

RESULTS
The Ezousas river cross two main geological units ranging from igneous rocks in its upper section (Troodos Terrane) to sedimentary rocks in its middle and lower sections (Circum Troodos Sedimentary Succession). Depending on the section, different terrace and floodplain levels can be distinguish. Uppersection Erosion-accumulative terrace about 30.0 m above river level (a.r.l.) and floodplain 0.3 m a.r.l. occur in the upper section (Fig. 3A). It had been dated to 53.3±8 ka (Fig. 3B) and to 19.7±2.9 ka, respectively (Table 1). Characteristic feature of alluvium in this section is large part (up to 24%) of none-rounded grains. There are colluvium deposits transported from the rockwalls and steep slopes of the valley (Fig. 3A)

Middle section
In the middle section of Ezousas river valley accumulative levels occurred. The highest level of 2.6 m a.r.l was described as Holocene alluvia (Sequence EZG). The grading lower unit of this series with a sherd dated to 1300 AD was accumulated in 4 phases with variable velocity of the stream. The poorly sorted structure of the upper unit above was a result of a single flood event. After the flooding, the river deposited overbank sediments in the top of outcrop [12]. Flood plain level of 1.0 m a.r.l. has been dated to 63.2±9.5 ka ( Table 2). Next level is 0.5 m a. r. l. and it is dating to 13.6±2.0 ka. Subsequent four sites were situated on the same high 0.2 m a.r.l. and alluvium were dated to 63.1±9.5 ka, (Fig. 4)    Tomasz Kalicki et al..

Lower section
In the lower section of the Ezousas river valley, the highest erosion-accumulative terrace on limestone monocline is 30.0 m a.r.l. Two alluvial series in superposition occurred here. The upper one, about 5 m thick, is dating to 18.9±2.8 ka very similar to landslide block at 25.0 m a.r.l. of this alluvium -22.4±3.4 ka ( Table 3). The lower series at 26.5 m a.r.l. was dating to 57.4±8.6 ka. Next were located on accumulative levels. Terrace 11.0 m a.r.l. was dated to 57.9±8.7 ka (Fig. 5) and level about 2.5 m a.r.l. to 64.8±9.7 ka. Flood plain levels about 1.2 m a.r.l. and 0.2 m a.r.l. were dated to 22.3±3.3 ka and to 16.1±2.4 ka respectively. The thickness of the Pleistocene alluvium cut and fills is bigger than in the middle and upper reaches. The. Holocene sediments (Sequence EZA) are also described in this section. Alluvium from the Roman period (1.5 m a.r.l.) were covered by Roman and Medieval colluvium 2.5 m thick [12].

CONCLUSIONS
In the Ezousas river valley there were very strong alluviation in the Pleistocene and small one in the Holocene. Two main alluviation phases can be distinguish: 75-48 ka and 25-13 ka (Fig. 6). There is no geological data about increased neotectonic movements in these phases. Therefore, an increased alluviation in Cyprus have been probably associated with climate change.. Similar fact is also confirmed in the valleys of SE Poland [13]. In both phases the correctness of the increase in the number of dates along the course of the river occurred. This is caused by a clear intensification of the erosion process in the mountain section of the river, where few alluvial covers have been preserved and a distinct alluviation (accumulation) in the middle and lower sections.