Its a cascading rollback. As you can see in the table given below, both the transactions are working only on a single data item i.e., 'X' throughout.
Now in line-2, when T2 writes a value of data item X, then it associates itself with that data item. Now it becomes responsible for what would be the final value of X till line-2.
Moving further we see that in line-3, even transaction T1 writes a value of the data item X, thereby associating itself too with that data item.
Now these writes performed by T1 and T2 are called as Blind Writes because they wrote without reading the value of X.
This schedule is cascading rollback because T1 is dependent on T2 and since an 'abort' in T2 is taking place before committing the value of X therefore T1 would also be rolled back to maintain the consistency of the value of X.