Summary
Exploration for Hydrocarbon accumulations in Upper Cretaceous Hartha and Sadi formations has not been given serious attention till recently in the State of Kuwait. The hydrocarbon shows encountered in Hartha section during the drilling of a Jurassic well in South Burgan area changed this perception and conscious efforts are made to explore the potential of this new Hartha play in the area. A detailed analysis of the mapped structure with the oil/gas indications both on and off the structure from the mud logs clearly show that, present day structural configuration has a limited role in these hydrocarbon accumulations and the play appear to be primarily strati-structural in nature. Windowed amplitude attribute maps generated from Hartha Formation clearly brought some predominately NE-SW trending long linear anomalous amplitude bodies which are coinciding with the hydrocarbon indications. To further validate these stratigraphic features in Hartha and to better understand reservoir facies distributions, an integrated approach had been adopted in relating the seismic data with hydrocarbon indications through a combination of seismic attributes like instantaneous frequency, phase, spectral decomposition as well as waveform classification coupled with impedance data. The geologic model postulated with seismic is calibrated with the petrophysical data and the results are validated by the good oil and gas shows in the two recently drilled wells in the area. The study has established that systematic workflow adopted through integrated analysis of seismic attributes is the key in defining reservoir geometry and resulting in deciphering a new stratigraphic play in rich petroliferous province like Kuwait.
Introduction
The Greater Burgan, situated in the southeastern part of Kuwait, is a group of three closely spaced fields which includes the giant anticlinal structure Burgan field and the smaller Magwa and Ahmadi fields. While Cretaceous reservoirs like Wara, Burgan and Minagish contribute most to the oil production, hydrocarbon accumulations in Hartha of Upper Cretaceous age has not been reported from Burgan area. The current study area is in the southern part of Burgan. Recently during the drilling of an exploratory well for Jurassic targets, good oil & gas were observed in Hartha and Sadi Formations (Figure 2). The gross lithology of the Hartha Fm. is limestone with interbedded shales.
