  We present a development of a geometric approach to entanglement indicators.
The method is applied to detect genuine multiqubit entanglement. The criteria
are given in form of non-linear conditions imposed on correlation tensors. Thus
they involve directly observable quantities, and in some cases require only few
specific measurements to find multiqubit entanglement. The non-linearity of
each of the criteria allows detection of entanglement in wide classes of
states. In contrast to entanglement witnesses, which in the space of Hermitian
operators define a hyperplane, the new conditions define a geometric figure
encapsulating the non-fully entangled states within it.
