*2.3.2 Calculation gravity effects theoretically, with heterogeneous test model 1*

The previously, the hypothetical depositional basin model-1 (**Figure 2**) consists of five formations layered slab deposited according to Walther's Law of deposition. Therefore, the formations are filling-basin in five-rows (N = 5), and nine- columns (juxtaposing vertical columns). The formations' thicknesses, depths, and densities are given, as seen in **Table 1**. Where Δρv1(i), represents here; the average vertical density-contrast for formations, stacked in nine columns of rows numbers N-4, N-3, N-2, N-1, and N respectively, and symmetrically repeated around the maximum formation's thicknesses (central basin where N = 4). By using the equations from (8) to (13) using the Matlab code, the summation values of the vertical effects for stacked slab' columns, at each point at x(i)-coordinates (x(i) = �4, �3, �2, �1, 0, 1,


**Table 1.**

*Data for hypothetical theoretical horizontal slab model (1) of heterogeneous densities distribution.*

2, 3, and 4.), are calculated; as well as the formation's thicknesses and depths, are obtained and summarized by following, **Table 2**, where, the formation depths' calculated are: 0.5, 1.5, 1.8, 3.5, and 4.0 km, are corresponding to the thicknesses (h (i)) of each formation sediments in the filling-basin, densities (1.900, 2.350, 2.450, 550, and 2.75 gm/cm<sup>3</sup> ), and the calculated gravity effect curve of the hypothetical sedimentary basin, representing model-1 is seen (**Figure 4**). The depth of the basement is assumed as 4.5 km, and its density is 2.670 gm/cm<sup>3</sup> .
