Drilling activity recommendation system and method

1. A method for planning a well, comprising:

receiving an initial drill plan for drilling a target well, the initial drill plan including a set of drilling activities including a first drilling activity and a consecutive second drilling activity;

obtaining one or more offset well drilling activity logs generated based on drilling offset wells;

determining, based on the one or more offset well drilling activity logs, a conditional probability of occurrence of one or more drilling activities between the first drilling activity and the second drilling activity;

automatically generating a modified drill plan for drilling the target well by adding the one or more drilling activities to the initial drill plan between the first drilling activity and the second drilling activity, wherein the adding the one or more drilling activities is based on the conditional probability of the occurrence of the one or more drilling activities between the first drilling activity and the second drilling activity; and

drilling the target well, by an automated well drilling system, based on the modified drill plan, wherein the drilling the target well includes:

performing the first drilling activity;

performing the one or more drilling activities after performing the first drilling activity; and

performing the second drilling activity after performing the one or more drilling activities,

wherein automatically generating the modified drill plan comprises:

constructing an offset well drilling run statistical tree based on the one or more offset well drilling activity logs, wherein the offset well drilling run statistical tree comprises probabilities for activities in sequences of drilling activities, and wherein constructing the offset well drilling statistical tree comprises partitioning the one or more offset well drilling activity logs into fragments, and defining nodes in the tree based on the fragments, wherein the nodes each represent an individual activity in the individual fragments and an order in which the nodes appear in the individual fragments, and the nodes are arranged in a parent-child relationship based on the fragments;

selecting a first sequence of activities that ends with the first drilling activity;

selecting the second drilling activity from the initial drill plan;

determining one or more first paths in the tree from a node representing the first drilling activity in the first sequence of activities to a node representing the second drilling activity; and

selecting a first path from the one or more first paths in the tree based at least in part on a conditional probability of the first path.

2. The method of claim 1 , wherein the nodes each represent data representing:

a frequency representing a total number of times the node appears in sequence in the fragments;

a number of children of the node, wherein the number of children is the number of times the node appears in sequence in, but is not the last node of, the fragments; and

a probability representing the frequency of the node divided the number of children of a parent node of the node.

3. The method of claim 1 , wherein automatically generating the modified drill plan further comprises:

selecting a second sequence of activities that ends with the first drilling activity in a current recommendation, the second sequence being different from the first sequence;

determining one or more second paths in the tree from a node representing the first drilling activity in the second sequence of activities to a node representing the second drilling activity, the node representing the first drilling activity in the second sequence being different from the node representing the first drilling activity in the first sequence;

selecting a second path from the one or more second paths based at least in part on a conditional probability of the second path;

selecting the first path and not the second path based at least in part on the conditional probabilities of the first and second paths; and

adding the first path to the modified drill plan between the first drilling activity and the second drilling activity.

4. The method of claim 3 , wherein the second sequence starts at least one activity after the first sequence.

5. A computing system, comprising:

one or more processors; and

a memory system including one or more non-transitory, computer-readable media storing instructions that, when executed by at least one of the one or more processors, cause the computing system to perform operations, the operations comprising:

receiving an initial drill plan for drilling a target well, the initial drill plan including a set of drilling activities including a first drilling activity and a consecutive second drilling activity;

obtaining one or more offset well drilling activity logs generated based on drilling offset wells;

determining, based on the one or more offset well drilling activity logs, a conditional probability of occurrence of one or more drilling activities between the first drilling activity and the second drilling activity;

automatically generating a modified drill plan for drilling the target well by adding the one or more drilling activities to the initial drill plan between the first drilling activity and the second drilling activity, wherein the adding the one or more drilling activities is based on the conditional probability of the occurrence of the one or more drilling activities between the first drilling activity and the second drilling activity; and

drilling the target well, by an automated well drilling system, based on the modified drill plan, wherein the drilling the target well includes:

performing the first drilling activity;

performing the one or more drilling activities after performing the first drilling activity; and

performing the second drilling activity after performing the one or more drilling activities,

wherein automatically generating the modified drill plan comprises:

constructing an offset well drilling run statistical tree based on the one or more offset well drilling activity logs, wherein the offset well drilling run statistical tree comprises probabilities for activities in sequences of drilling activities, and wherein constructing the offset well drilling statistical tree comprises partitioning the one or more offset well drilling activity logs into fragments, and defining nodes in the tree based on the fragments, wherein the nodes each represent an individual activity in the individual fragments and an order in which the nodes appear in the individual fragments, and the nodes are arranged in a parent-child relationship based on the fragments;

selecting a first sequence of activities that ends with the first drilling activity;

selecting the second drilling activity from the initial drill plan;

determining one or more first paths in the tree from a node representing the first drilling activity in the first sequence of activities to a node representing the second drilling activity; and

selecting a first path from the one or more first paths in the tree based at least in part on a conditional probability of the first path.

6. The system of claim 5 , wherein the nodes each represent data representing:

a frequency representing a total number of times the node appears in sequence in the fragments;

a number of children of the node, wherein the number of children is the number of times the node appears in sequence in, but is not the last node of, the fragments; and

a probability representing the frequency of the node divided the number of children of a parent node of the node.

7. The system of claim 5 , wherein automatically generating the modified drill plan further comprises:

selecting a second sequence of activities that ends with the first drilling activity in a current recommendation, the second sequence being different from the first sequence;

determining one or more second paths in the tree from a node representing the first drilling activity in the second sequence of activities to a node representing the second drilling activity, the node representing the first drilling activity in the second sequence being different from the node representing the first drilling activity in the first sequence;

selecting a second path from the one or more second paths based at least in part on a conditional probability of the second path;

selecting the first path and not the second path based at least in part on the conditional probabilities of the first and second paths; and

adding the first path to the modified drill plan between the first drilling activity and the second drilling activity.

8. The system of claim 7 , wherein the second sequence starts at least one activity after the first sequence.

9. A non-transitory computer-readable medium storing instructions that, when executed by at least one processor of a computing system, cause the computing system to perform operations, the operations comprising:

receiving an initial drill plan for drilling a target well, the initial drill plan including a set of drilling activities including a first drilling activity and a consecutive second drilling activity;

obtaining one or more offset well drilling activity logs generated based on drilling offset wells;

determining, based on the one or more offset well drilling activity logs, a conditional probability of occurrence of one or more drilling activities between the first drilling activity and the second drilling activity;

automatically generating a modified drill plan for drilling the target well by adding the one or more drilling activities to the initial drill plan between the first drilling activity and the second drilling activity, wherein the adding the one or more drilling activities is based on the conditional probability of the occurrence of the one or more drilling activities between the first drilling activity and the second drilling activity; and

drilling the target well, by an automated well drilling system, based on the modified drill plan, wherein the drilling the target well includes:

performing the first drilling activity;

performing the one or more drilling activities after performing the first drilling activity; and

performing the second drilling activity after performing the one or more drilling activities,

wherein automatically generating the modified drill plan comprises:

constructing an offset well drilling run statistical tree based on the one or more offset well drilling activity logs, wherein the offset well drilling run statistical tree comprises probabilities for activities in sequences of drilling activities, and wherein constructing the offset well drilling statistical tree comprises partitioning the one or more offset well drilling activity logs into fragments, and defining nodes in the tree based on the fragments, wherein the nodes each represent an individual activity in the individual fragments and an order in which the nodes appear in the individual fragments, and the nodes are arranged in a parent-child relationship based on the fragments;

selecting a first sequence of activities that ends with the first drilling activity;

selecting the second drilling activity from the initial drill plan;

determining one or more first paths in the tree from a node representing the first drilling activity in the first sequence of activities to a node representing the second drilling activity; and

selecting a first path from the one or more first paths in the tree based at least in part on a conditional probability of the first path.

10. The medium of claim 9 , wherein the nodes each represent data representing:

a frequency representing a total number of times the node appears in sequence in the fragments;

a number of children of the node, wherein the number of children is the number of times the node appears in sequence in, but is not the last node of, the fragments; and

a probability representing the frequency of the node divided the number of children of a parent node of the node.

11. The medium of claim 9 , wherein:

automatically generating the modified drill plan further comprises:

selecting a second sequence of activities that ends with the first drilling activity in a current recommendation, the second sequence being different from the first sequence;

determining one or more second paths in the tree from a node representing the first drilling activity in the second sequence of activities to a node representing the second drilling activity, the node representing the first drilling activity in the second sequence being different from the node representing the first drilling activity in the first sequence;

selecting a second path from the one or more second paths based at least in part on a conditional probability of the second path;

selecting the first path and not the second path based at least in part on the conditional probabilities of the first and second paths; and

adding the first path to the modified drill plan between the first drilling activity and the second drilling activity; and

the second sequence starts at least one activity after the first sequence.