2004
DETERMINATION OF BOUNDARIES, GEOLOGICAL OUTCROPS AND STRUCTURAL FEATURES OF THE SIVAS
TERTIARY BASIN/TURKEY USING LANDSAT TM/ETM+ AND SPOT XS IMAGES
e
K. S. Kavak
ie Cumhuriyet University, Engineering Faculty, Dept. of Geological Engineering, 58140 Sivas/Turkey-(kaank@cumhuriyet.edu.tr)
S
s. Commission VII, WG VII/4
S KEY WORDS: Classification, DEM/DTM, Fusion, Geology, Imagery, Landsat
S,
h ABSTRACT:
d The Sivas Basin is one of the most well known major Tertiary basins of the Anatolia connected with the evolution of the Neotethyan
le Ocean. Central Anatolian Thrust Belt contains realms of this ocean and bounds the basin from north. Therefore, realms of the Inner
n Tauride Ocean are also surrounded the basin from southeast and represented with allochthonous units. Axis of the eastern section of
le this basin lies approximately in E-W trending between Erzincan and Sivas settlements, This trend turns toward NE-SW between
)- Sivas and Kayseri in west. This roughly huge elliptical basin characterizes within several sedimentary, magmatic and metamorphic
at occurrences because of varying events during its complex geological history. The basin also exhibits spectacular structural features in
id regional scale such as foldings and faultings. It is possible to see evidences of these intensive deformations because of NNW-SSE
a compression regime developing after Miocene. Under this stress regime, Oligocene continental deposits were deformed by
1e decollément gypsum levels.
n. Sivas Basin also provides easiness of interpretation geologically utilizing multispectral data sets such as SPOT XS and Landsat
al ETM+ considering that the arid climatic conditions of the region. In this study, image processing methods such as principal
component analysis and classification methods were applied to highlight lithological features of the basin. Additionally, DEM
analysis was also realized to expose structural features of the basin. These remote sensing studies were supported by field campaigns
ds which were realized during last few years.
is 1984). The massif is located in Anatolides-Taurides, as one of
is 1. INTRODUCTION | the main tectonic units of Turkey (Ketin, 1966). This fragment
s. was composed of mainly metamorphic occurrences and
ry This study aims to evaluate the Sivas Tertiary Basin intrusives. On the other hand, Inner Tauride Suture separates
et geologically using multispectral data sources such as Landsat Munzur and Bitlis prolongations and bounds the basin from
to TM/ETM+ and SPOT images. Image processing techniques south (Sengor and Yilmaz, 1981). This suture also determines
ill were realized with the aid of ER Mapper 6.4 image processing southern branch of the Neotethyan ocean.
al software. SRTM-3 data
ne (fip://edesgs9.cr.usgs.gov/pub/data/srtm/Eurasia) which
al contains the basin overall was used to evaluate the region in ae | IN
lo terms of structurally.
ly Sivas Basin is defined as a peripheral foreland basin in terms of CE
he evolutionary processes and contains varying metamorphic, Let Ankara
magmatic and sedimentary occurrences (Poisson et. al., 1996, ANMOLIDES
Gorur et. al., 1998). The basin represents many
nd pua
ds spectacular remarks of continental deformation and lies on 7 Kanga Basin
as Alpine-Himalayan tectonic belt (Figure 1) in Turkey's political (7/77, Krsehir Massit
ne boundaries. The basin also hides kinematic evidences of III] Ponties
nd ongoing convergence between Eurasian, Arabian and African NSNS Teurides
an plates since Late Cretaceous time. Kavak et. al., (1997) and Ne Are aoe
h- Kavak and Inan (2002) documented that the compressional
an regime was active in the NNW-SSE direction after post- MEDITERRANEAN SEA 9 ae
dn Pliocene and demonstrated that several lineament systems were Figure 1. Location map of the Sivas Tertiary Basin (modified
connected to this direction by using several satellite image from Poisson et. al., 1996).
enhancement methods.
The basin presents considerable examples of collision tectonics One of the most detailed studies to expose the tectono-
lia and contains particularly sediments of shallow marine and stratigraphic setting and evolutionary development of the Sivas
es continental environment starting from Upper Paleocene-Eocene. Basin was realized by Poisson et. al. (1996). The authors
ill 2. GEOLOGIC SETTING claimed that the basin has continental basement rather than an
be : e oceanic crust. According to them, décollement Oligocene
ed Sivas Basin is surrounded several litospheric fragments and gypsum levels determine tectono-stratigraphic evolution of the
m suture zones (Figure 1). First of all, Central Anatolian Thrust basin. The basin elongates roughly in NE-SW direction.
Belt (Tatar, 1982) is located on the northern margin of the basin Decollément gypsum levels in evaporitic rocks dip gently
and represents as a suture zone on the northern branch ol toward the continent and it is possible to see remarkable
Neotethyan Ocean which was also known Izmir-Ankara Zone examples of these levels on satellite imagery in white tones such
(Brinkmann, 1976). This collisional process was realized on the as Landsat ETM+ images (Figure 2).
southern margin of the Eurasian plate and the Apulo-Anatolian
block in regional scale (Poisson et. al., 1996). Kirsehir Massif is
formed roughly continental basement of the basin (Gorur et. al.,
549
