Is this just a rock or an Underground secret base

Whilst scanning for dulce base on google earth came across a way rock formation or not looks different to the others anyone have any idea looks like an opening or a shadow I cant tell https://earth.google.com/web/search/36%2e94023229487415,+-106%2e82757017829468/@36.97153651,-106.80045457,2489.3887026a,92.8985474d,35y,133.97584804h,45.38804195t,0r/data=CiwiJgokCfdSsVbieEJAEQhdgCnyakJAGXedQnmUpVrAIXfzdBqWslrAQgIIAToDCgEwQgIIAEoNCP___________wEQAA?authuser=0