What exactly is Emotional Reasoning? Emotional Reasoning, a cognitive distortion discovered by Aaron T. Beck, as stated on Wikipedia:


  Emotional reasoning is a cognitive process by which a person concludes that his/her emotional reaction proves something is true, regardless of the observed evidence. For example, even though a spouse has shown only devotion, a person using emotional reasoning might conclude, "I know my spouse is being unfaithful because I feel jealous."


If I go to an haunted place, and I become really anxious there, so my emotions are representing my thoughts about that place. So it's simple: you feel the way you think. How does Emotional Reasoning fit in this scene, or is it something else?
The quote you gave was from the beginning of Wikipedia article on Emotional Reasoning and if you read further down in that article it tells you that


  Beck believed that emotional reasoning stemmed from negative thoughts that were uncontrollable and happened without effort.


Emotional Reasoning is a cognitive distortion which amplifies the effects of other cognitive distortions and it is a style of unhelpful thinking whereby you base your view of situations, yourself, or others, on the way you are thinking.  What you are thinking and feeling could be rational but with this situation you are thinking irrationally as there is no hard factual evidence to support the thoughts.

You might think "I feel like an idiot, therefore I am an idiot"; "I feel guilty, therefore I must have done something bad";  "I feel inadequate, therefore I must be a worthless person"; "I'm furious with you, therefore you must have been acting badly and trying to take advantage of me"

Or just as in the question but phrased in this way, "I feel jealous, therefore it must be true that my spouse is being unfaithful".

With Emotional Reasoning you are reacting to what you alone are witnessing.  The proposed situation regarding a haunted house making you feel anxious is not Emotional Reasoning.  You are feeling anxious because you are apprehensive of what might happen if you encounter a ghost/spirit some other people have said they have witnessed.