It depends on what version of the game you have too. I've checked Wisco's for you and found 2 different exhibits.
From "Unlock" Animals list:
Triceratops
Exhibit size: 20 x 10 (200 squares)
Fence Type: 40x concrete fence + 20x concrete chain fence
Terrain: 150 squares savannah, 10 squares fresh water, 10 squares sand and 30 squares dirt
Foliage: 18 squares full with thorn bush
Rocks: 16 small rocks
Shelter : none
Toy: no toy
Elevation: no elevation needed
Animals: 1 male and 1 female
Animal Happiness: 100
Suitability Rating: 101
Total Cost: $ 45.020
Cost/Square: $ 225,10
From Dino Digs list:
Triceratops (Dino Digs Version)
Exhibit size: 20 x 10 ( 200 squares )
Fence Type: 60x reinforced concrete and iron bar fence
Terrain: 150 squares savannah, 10 squares fresh water, 10 squares sand and 30 squares dirt
Foliage: 18 squares full with sigillaria tree
Rocks: 4 medium savannah rocks
Shelter: no shelter
Toy: no toy
Elevation : no elevation
Animals: 1 male and 1 female
Animal Happiness: between 94-100
Suitability Rating: 101
Total Cost: $ 45.500
Cost/Square: $ 227,50